全文获取类型
收费全文 | 5150篇 |
免费 | 146篇 |
国内免费 | 91篇 |
专业分类
管理学 | 400篇 |
劳动科学 | 2篇 |
民族学 | 84篇 |
人才学 | 1篇 |
人口学 | 89篇 |
丛书文集 | 597篇 |
理论方法论 | 212篇 |
综合类 | 3730篇 |
社会学 | 97篇 |
统计学 | 175篇 |
出版年
2024年 | 5篇 |
2023年 | 21篇 |
2022年 | 59篇 |
2021年 | 88篇 |
2020年 | 55篇 |
2019年 | 49篇 |
2018年 | 69篇 |
2017年 | 72篇 |
2016年 | 75篇 |
2015年 | 111篇 |
2014年 | 212篇 |
2013年 | 263篇 |
2012年 | 286篇 |
2011年 | 342篇 |
2010年 | 356篇 |
2009年 | 408篇 |
2008年 | 373篇 |
2007年 | 401篇 |
2006年 | 418篇 |
2005年 | 339篇 |
2004年 | 269篇 |
2003年 | 258篇 |
2002年 | 314篇 |
2001年 | 259篇 |
2000年 | 143篇 |
1999年 | 51篇 |
1998年 | 13篇 |
1997年 | 11篇 |
1996年 | 16篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 2篇 |
排序方式: 共有5387条查询结果,搜索用时 15 毫秒
11.
秦汉时期,是宗教与封建专制融合的时代,以方术、巫术为基础的宗天神学和谶纬神学得到统治者推崇,对秦汉政治、文化产生了深刻的影响,甚至秦汉时期许多封建礼制和典章制度,都源于方术及其相关的宗教信仰。而河北地区的燕赵故地,正是神学宗教盛行的地区。以大量史实为基础,研究秦汉礼制中蕴含的神学宗教,可剖析封建礼制与宗教的关系和相互作用。 相似文献
12.
13.
本文从啮合原理的角度出发,以任意角度ξ为危险截面,准确地导出了内齿轮齿形系数的数学表达式,解决了内齿轮弯曲强度中的齿形系数计算问题。 相似文献
14.
本文介绍一种以激光作为测量光源,利用光敏电阻随光线强弱变化而阻值随之变化的特性,控制或门电路工作,并在数字电压表上显示水面高度的测量仪。 相似文献
15.
This paper provides a practical simulation-based Bayesian analysis of parameter-driven models for time series Poisson data with the AR(1) latent process. The posterior distribution is simulated by a Gibbs sampling algorithm. Full conditional posterior distributions of unknown variables in the model are given in convenient forms for the Gibbs sampling algorithm. The case with missing observations is also discussed. The methods are applied to real polio data from 1970 to 1983. 相似文献
16.
17.
The general Gauss–Markov model, Y = Xβ + e, E(e) = 0, Cov(e) = σ 2 V, has been intensively studied and widely used. Most studies consider covariance matrices V that are nonsingular but we focus on the most difficult case wherein C(X), the column space of X, is not contained in C(V). This forces V to be singular. Under this condition there exist nontrivial linear functions of Q′Xβ that are known with probability 1 (perfectly) where ${C(Q)=C(V)^\perp}$ . To treat ${C(X) \not \subset C(V)}$ , much of the existing literature obtains estimates and tests by replacing V with a pseudo-covariance matrix T = V + XUX′ for some nonnegative definite U such that ${C(X) \subset C(T)}$ , see Christensen (Plane answers to complex questions: the theory of linear models, 2002, Chap. 10). We find it more intuitive to first eliminate what is known about Xβ and then to adjust X while keeping V unchanged. We show that we can decompose β into the sum of two orthogonal parts, β = β 0 + β 1, where β 0 is known. We also show that the unknown component of X β is ${X\beta_1 \equiv \tilde{X} \gamma}$ , where ${C(\tilde{X})=C(X)\cap C(V)}$ . We replace the original model with ${Y-X\beta_0=\tilde{X}\gamma+e}$ , E(e) = 0, ${Cov(e)=\sigma^2V}$ and perform estimation and tests under this new model for which the simplifying assumption ${C(\tilde{X}) \subset C(V)}$ holds. This allows us to focus on the part of that parameters that are not known perfectly. We show that this method provides the usual estimates and tests. 相似文献
18.
ABSTRACTIn this article, we study complete convergence of the nonidentically distributed pairwise negatively quadrant dependent (NQD) random sequences by the moment inequality and terminating random variables,which extend and improve the previous relevant results. 相似文献
19.
The authors develop consistent nonparametric estimation techniques for the directional mixing density. Classical spherical harmonics are used to adapt Euclidean techniques to this directional environment. Minimax rates of convergence are obtained for rotation ally invariant densities verifying various smoothness conditions. It is found that the differences in smoothness between the Laplace, the Gaussian and the von Mises‐Fisher distributions lead to contrasting inferential conclusions. 相似文献
20.
The main goal of phase I cancer clinical trials is to determine the highest dose of a new therapy associated with an acceptable level of toxicity for the use in a subsequent phase II trial. The continual reassessment method (CRM) [O’Quigley, J., Pepe, M., Fisher, L., 1990. Continual reassessment method: a practical design for phase I clinical trials in cancer. Biometrics 46, 33–48] and escalation with overdose control (EWOC) [Babb, J., Rogatko, A., Zacks, S., 1998. Cancer phase I clinical trials: efficient dose escalation with overdose control. Statist. Med. 17 (10), 1103–1120] are two model-based designs used for phase I cancer clinical trials. A few modifications of the (original) CRM and EWOC have been made by many authors. In this paper, we show how CRM and EWOC can be unified and present a hybrid design. We study the characteristics of the approach of the hybrid design. The comparisons of the three designs (CRM, EWOC, and the hybrid design) are presented by convergence rates and overdose proportions. The simulation results show that the hybrid design generally has faster convergence rates than EWOC and smaller overdose proportions than CRM, especially when the true maximum tolerated dose (MTD) is above the mid-level of the dose range considered. The performance of these three designs is also evaluated in terms of sensitivity to outliers. 相似文献