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51.
云天铨 《应用数学和力学(英文版)》2001,(1)
1 MeaningandMethodsofStudyingofFinancialDerivativesFinancialderivativesarethosefinancialproductswhicharederivedfrombasicasserts (orunderlyinginstrucments) (e .g .stock ,bond ,currency ,interestrate,etc.)oftraditionalmarkets(e.g .stockmarket,bond’smarket,currency… 相似文献
52.
Ivor Cribben 《商业与工业应用随机模型》2019,35(2):299-320
We propose two robust data‐driven techniques for detecting network structure change points between heavy‐tailed multivariate time series for situations where both the placement and number of change points are unknown. The first technique utilizes the graphical lasso method to estimate the change points, whereas the second technique utilizes the tlasso method. The techniques not only locate the change points but also estimate an undirected graph (or precision matrix) representing the relationship between the time series within each interval created by pairs of adjacent change points. An inference procedure on the edges is used in the graphs to effectively remove false‐positive edges, which are caused by the data deviating from normality. The techniques are compared using simulated multivariate t‐distributed (heavy‐tailed) time series data and the best method is applied to two financial returns data sets of stocks and indices. The results illustrate the method's ability to determine how the dependence structure of the returns changes over time. This information could potentially be used as a tool for portfolio optimization. 相似文献
53.
Jos Crispín Zavala-Díaz Joaquín Prez-Ortega Nelva Nely Almanza-Ortega Rodolfo Pazos-Rangel Jos María Rodríguez-Lelís 《Entropy (Basel, Switzerland)》2022,24(8)
Predicting the values of a financial time series is mainly a function of its price history, which depends on several factors, internal and external. With this history, it is possible to build an ∊-machine for predicting the financial time series. This work proposes considering the influence of a financial series through the transfer of entropy when the values of the other financial series are known. A method is proposed that considers the transfer of entropy for breaking the ties that occur when calculating the prediction with the ∊-machine. This analysis is carried out using data from six financial series: two American, the S&P 500 and the Nasdaq; two Asian, the Hang Seng and the Nikkei 225; and two European, the CAC 40 and the DAX. This work shows that it is possible to influence the prediction of the closing value of a series if the value of the influencing series is known. This work showed that the series that transfer the most information through entropy transfer are the American S&P 500 and Nasdaq, followed by the European DAX and CAC 40, and finally the Asian Nikkei 225 and Hang Seng. 相似文献
54.
M. Bartolozzi 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(3):337-345
Avalanches, or Avalanche-like, events are often
observed in the dynamical behaviour of many complex systems which
span from solar flaring to the Earth's crust dynamics and from
traffic flows to financial markets. Self-organized criticality
(SOC) is one of the most popular theories able to explain this
intermittent charge/discharge behaviour. Despite a large amount of
theoretical work, empirical tests for SOC are still in their
infancy. In the present paper we address the common problem of
revealing SOC from a simple time series without having much
information about the underlying system. As a working example we
use a modified version of the multifractal random walk originally
proposed as a model for the stock market dynamics. The study
reveals, despite the lack of the typical ingredients of SOC, an
avalanche-like dynamics similar to that of many physical systems.
While, on one hand, the results confirm the relevance of cascade
models in representing turbulent-like phenomena, on the other,
they also raise the question about the current state of
reliability of SOC inference from time series analysis. 相似文献
55.
M. Beben A. Orłowski 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,20(4):527-530
Long-time correlations in both well-developed and emerging market indexes are studied. The Hurst exponent as well as detrended
fluctuations analysis (DFA) are used as technical tools. Some features that seem to be specific for developing markets are
discovered and briefly discussed.
Received 17 October 2000 相似文献
56.
O. S. Klass O. Biham M. Levy O. Malcai S. Solomon 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(2):143-147
Statistical regularities at
the top end of the wealth distribution in the United States are
examined using the Forbes 400 lists of richest Americans,
published between 1988 and 2003.
It is found that the wealths are distributed according to a power-law
(Pareto) distribution.
This result is explained using a
simple stochastic model
of multiple investors that incorporates the
efficient market hypothesis
as well as the multiplicative nature of financial market fluctuations. 相似文献
57.
P2P网络借贷是中国互联网金融的重要业态之一,在短短几年的发展过程中先后呈现出野蛮生长与快速清退、监管缺失与监管频出、风险积聚与风险爆发等鲜明而又迥异的市场特征。本文基于P2P网络借贷市场最有代表性的一手微观数据,系统地分析了这一新兴互联网金融业态的发展与风险特征,并且特别聚焦于前期的监管缺失以及之后密集出台的监管政策对市场风险爆发可能产生的影响,力图为今后针对新兴互联网金融业态的风险监管提供实证的依据。 相似文献
58.
从历史和全球的视角来看,改革开放以来中国以银行改革为主体的金融改革实践取得了良好的经济绩效,金融发展取得了历史性成就,有力地支撑了中国经济的高速增长。同时,中国还成功经受住了历次金融危机的严峻考验,切实维护了金融稳定,可谓走出了一条符合中国国情的正确的金融改革发展道路。进入新时代,中国金融已不能完全适应经济高质量发展的需要,迫切需要深化金融改革,推动金融业高质量发展。为此,中国应立足当前经济转型的需要,根据自身金融改革的实践经验,继续走中国特色金融改革发展道路,通过进一步深化金融改革,推动中国金融朝着优化结构、提高效率、安全稳定的方向发展。 相似文献
59.
Sahar Erfanian Yewang Zhou Amar Razzaq Azhar Abbas Asif Ali Safeer Teng Li 《Entropy (Basel, Switzerland)》2022,24(10)
Bitcoin (BTC)—the first cryptocurrency—is a decentralized network used to make private, anonymous, peer-to-peer transactions worldwide, yet there are numerous issues in its pricing due to its arbitrary nature, thus limiting its use due to skepticism among businesses and households. However, there is a vast scope of machine learning approaches to predict future prices precisely. One of the major problems with previous research on BTC price predictions is that they are primarily empirical research lacking sufficient analytical support to back up the claims. Therefore, this study aims to solve the BTC price prediction problem in the context of both macroeconomic and microeconomic theories by applying new machine learning methods. Previous work, however, shows mixed evidence of the superiority of machine learning over statistical analysis and vice versa, so more research is needed. This paper applies comparative approaches, including ordinary least squares (OLS), Ensemble learning, support vector regression (SVR), and multilayer perceptron (MLP), to investigate whether the macroeconomic, microeconomic, technical, and blockchain indicators based on economic theories predict the BTC price or not. The findings point out that some technical indicators are significant short-run BTC price predictors, thus confirming the validity of technical analysis. Moreover, macroeconomic and blockchain indicators are found to be significant long-term predictors, implying that supply, demand, and cost-based pricing theories are the underlying theories of BTC price prediction. Likewise, SVR is found to be superior to other machine learning and traditional models. This research’s innovation is looking at BTC price prediction through theoretical aspects. The overall findings show that SVR is superior to other machine learning models and traditional models. This paper has several contributions. It can contribute to international finance to be used as a reference for setting asset pricing and improved investment decision-making. It also contributes to the economics of BTC price prediction by introducing its theoretical background. Moreover, as the authors still doubt whether machine learning can beat the traditional methods in BTC price prediction, this research contributes to machine learning configuration and helping developers use it as a benchmark. 相似文献
60.
Finding the critical factor and possible “Newton’s laws” in financial markets has been an important issue. However, with the development of information and communication technologies, financial models are becoming more realistic but complex, contradicting the objective law “Greatest truths are the simplest.” Therefore, this paper presents an evolutionary model independent of micro features and attempts to discover the most critical factor. In the model, information is the only critical factor, and stock price is the emergence of collective behavior. The statistical properties of the model are significantly similar to the real market. It also explains the correlations of stocks within an industry, which provides a new idea for studying critical factors and core structures in the financial markets. 相似文献