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141.
上市公司财务危机动态预测模型研究 总被引:2,自引:0,他引:2
预测上市公司财务危机是投资者、债权人及证券市场监管机构所广泛关注的课题.运用现代资本结构理论和期权模型,以企业“资不抵债”作为上市公司陷入财务危机的标志,利用资本市场的信息指标——股价建立起上市公司动态财务危机预测模型,克服了统计预测方法利用财务报表信息预测的时期性和滞后性的缺陷. 相似文献
142.
V. P. Maslov 《Mathematical Notes》2006,80(3-4):539-541
We give a risk-minimizing formula for government investments taking into account the zero intelligence law for financial markets. 相似文献
143.
J.-P. Bouchaud L. Laloux M. A. Miceli M. Potters 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(2):201-207
We present a general method to detect and extract
from a finite time sample statistically meaningful correlations between input and output variables of large dimensionality.
Our central result is derived from the theory of free random matrices, and gives an explicit expression for the interval where
singular values are expected in the absence of any true correlations between the variables under study. Our result can be
seen as the natural generalization of the Marčenko-Pastur distribution for the case of rectangular correlation matrices. We
illustrate the interest of our method on a set of macroeconomic time series. 相似文献
144.
U. Garibaldi E. Scalas P. Viarengo 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):241-246
We propose a simple stochastic exchange game mimicking
taxation and redistribution. There are g agents and n coins;
taxation is modeled by randomly extracting some coins; then, these
coins are redistributed to agents following Polya's scheme. The
individual wealth equilibrium distribution for the resulting Markov
chain is the multivariate symmetric Polya distribution. In the
continuum limit, the wealth distribution converges to a Gamma
distribution, whose form factor is just the initial redistribution
weight. The relationship between this taxation-and-redistribution
scheme and other simple conservative stochastic exchange games (such
as the BDY game) is discussed. 相似文献
145.
Yuji?YoshidaEmail author Masami?Yasuda Jun-ichi?Nakagami Masami?Kurano 《Fuzzy Optimization and Decision Making》2005,4(3):191-207
To solve a mathematical model for American put option with uncertainty, we utilize two essentials, i.e., a λ-weighting function and a mean value of fuzzy random variables simultaneously. Estimation of randomness and fuzziness as uncertainty should be important when we deal with a reasonable and natural model extended from the original optimization/decision making. Three kinds of mean values by fuzzy measures, which are based on Possibility, Necessity and Credibility, are demonstrated particularly. We consider the optimal expected price of the American put option by dynamic programming under a reasonable assumption. A numerical example is given to illustrate our idea. 相似文献
146.
S. Solomon P. Richmond 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(2):257-261
In recent years we have found that logistic systems of the Generalized Lotka-Volterra type (GLV) describing statistical systems
of auto-catalytic elements posses power law distributions of the Pareto-Zipf type. In particular, when applied to economic
systems, GLV leads to power laws in the relative individual wealth distribution and in market returns. These power laws and
their exponent α are invariant to arbitrary variations in the total wealth of the system and to other endogenously and exogenously
induced variations.
Received 31 December 2001 相似文献
147.
主成份分析在证券市场个股评析中的应用 总被引:15,自引:3,他引:12
本文利用主成份分析方法 ,对证券市场上 31种股票进行综合评价 ,通过使用统计软件SAS进行计算和分析 ,提出用第一主成份作为个股业绩的度量 ,得到了这些股票 1997年上半年财务状况的排列次序 相似文献
148.
ZHENGZhi-Gang 《理论物理通讯》2002,37(5):557-560
The phase-locking dynamics in 1D and 2D lattices of non-identical coupled circle maps is explored.A global phase locking can be attained via a cascade of clustering processes with the increase of the coupling strength.Collective spatiotemporal dynamics is observed when a global phase locking is reached.Crisis-induced desynchronization is found,and its consequent spatiotemporal chaos is studied. 相似文献
149.
150.
中央银行外汇干预的有效性一直是金融领域研究和争论的热点问题,并且至今尚未达成一致的结论,寻找科学的理论与方法对其做进一步的探讨具有重要意义。针对该问题提出一种新的解决方案,即在扩展Dorn-busch汇率模型基础上,运用自适应混沌控制方法指导外汇干预策略,试图通过检验干预是否能够控制汇率时间序列的混沌行为并最终达到稳定汇率的目的,来论证外汇干预的有效性。仿真结果表明,通过自适应地寻找合理的干预尺度,外汇干预行为最终能够成功地将汇率稳定在系统均衡水平上。研究成果不但为外汇干预有效性给出了理论支持,还为中央银行外汇干预策略的制定提供了参考。 相似文献