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81.
In this paper, we discuss the premium principle in uncertain environment. First, the net premium principle for uncertain risks is presented within the framework of uncertainty theory. With the help of distortion function, a new uncertain premium principle is derived from the uncertain net premium. Some properties of uncertain distortion premium principle are proved. Furthermore, a sufficient and necessary condition that an uncertain premium principle is an uncertain distortion premium principle has been characterized. Finally, some examples are given to illustrate the calculations of the uncertain distortion premium. 相似文献
82.
The management of Operational Risk has been a difficult task due to the lack of data and the high number of variables. In
this project, we treat operational risks as multivariate variables. In order to model them, copula functions are employed,
which are a widely used tool in finance and engineering for building flexible joint distributions. The purpose of this research
is to propose a new methodology for modelling Operational Risks and estimating the required capital. It combines the use of
graphical models and the use of copula functions along with hyper-Markov law. Historical loss data of an Italian bank is used,
in order to explore the methodology’s behaviour and its potential benefits.
相似文献
83.
Amogh Deshpande Srikanth K. Iyer 《Central European Journal of Operations Research》2009,17(2):219-228
We consider an enhancement of the credit risk+ model to incorporate correlations between sectors. We model the sector default rates as linear combinations of a common set
of independent variables that represent macro-economic variables or risk factors. We also derive the formula for exact VaR contributions at the obligor level. 相似文献
84.
In participating life insurance, management decisions regarding the asset composition can substantially impact the value of a policy from the policyholders’ perspective as well as the insurer’s risk situation. Due to the long-term guarantees often embedded in these contracts, life insurers typically invest a considerable portion of their capital in long-term assets such as corporate and government bonds. Besides interest rate risk, the value of these bond investments is thus particularly influenced by credit risk. Thus, the aim of this paper is to examine the impact of market risk associated with the asset composition on fair valuation and risk assessment with focus on credit risk and its interaction with equity risk and interest rate risk. Our analysis emphasizes that the consideration of credit risk associated with bonds has a strong impact on the fair valuation and risk measurement in the context of participating life insurance contracts, even in case of higher grade bond exposures. 相似文献
85.
Some research on cyber risk has been conducted in the field of information technology, but virtually no research exists in the actuarial domain. As a first step toward a more profound actuarial discussion, we use multidimensional scaling and goodness-of-fit tests to analyze the distribution of data breach information. Our results show that different types of data breaches need to be modeled as distinct risk categories. For severity modeling, the log-skew-normal distribution provides promising results. The findings add to the recent discussion on the use of skewed distributions in actuarial modeling (Vernic, 2006; Bolancé et al., 2008; Eling, 2012). Moreover, they provide useful insights for actuaries working on the implementation of cyber insurance policies. We illustrate the usefulness of our results in two applications on risk measurement and pricing. 相似文献
86.
87.
WANG Ling-ling DU Zhen-wu LIU Jia-nan WU Mei SONG Yang JIANG Ri-hua ZHANG Gui-zhen 《高等学校化学研究》2012,28(2)
We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-a-308G/A on the onset and development of T2DM in a North... 相似文献
88.
Models for diseases spreading are not just limited to SIS or SIR. For instance, for the spreading of AIDS/HIV, the susceptible individuals can be classified into different cases according to their immunity, and similarly, the infected individuals can be sorted into different classes according to their infectivity. Moreover, some diseases may develop through several stages. Many authors have shown that the individuals' relation can be viewed as a complex network. So in this paper, in order to better explain the dynamical behavior of epidemics, we consider different epidemic models on complex networks, and obtain the epidemic threshold for each ease. Finally, we present numerical simulations for each case to verify our results. 相似文献
89.
In this paper we study a family of stochastic orders of random variables defined via the comparison of their percentile residual life functions. Some interpretations of these stochastic orders are given, and various properties of them are derived. The relationships to other stochastic orders are also studied. Finally, some applications in reliability theory and finance are described. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
90.
This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with given initial environment state, is derived and solved. Explicit formulas for the discounted penalty function are obtained when the initial surplus is zero or when all the claim amount distributions are from rational family. In two state model, numerical illustrations with exponential claim amounts are given. 相似文献