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31.
Generalized partially linear varying-coefficient models 总被引:1,自引:0,他引:1
Generalized varying-coefficient models are useful extensions of generalized linear models. They arise naturally when investigating how regression coefficients change over different groups characterized by certain covariates such as age. In this paper, we extend these models to generalized partially linear varying-coefficient models, in which some coefficients are constants and the others are functions of certain covariates. Procedures for estimating the linear and non-parametric parts are developed and their associated statistical properties are studied. The methods proposed are illustrated using some simulations and real data analysis. 相似文献
32.
黄阳 《广西大学学报(社会科学版)》2008,30(Z2)
形式和意义的关联性是分析现代汉语Nl N2同位结构的关键.意义的差异是形式差异得以存在的理由,同位结构的组配关系很大程度上是由意义类别决定的,而所谓的同位不但存在并立性而且还具有一定的修饰关系.人类对客观世界的认识角度会影响到此结构的组配,这种认识来源于社会文化的差异及个人的认知凸现能力.同时N1 N2同位结构和定中结构之间存在一定的纠缠,消除纠缠的方法建立在对结构内部变元成分套累情况的认识上. 相似文献
33.
浅析数字化校园及其应用系统的构建 总被引:1,自引:0,他引:1
数字化校园是在高等教育信息化快速发展过程中出现的一个崭新概念。本文介绍了数字化校园的内涵、数字化校园建设的主要内容,分析和评价了一些构建数字化校园应用系统的技术,对目前正在兴起的数字化校园建设具有一定的参考意义。 相似文献
34.
The basic assumption underlying the concept of ranked set sampling is that actual measurement of units is expensive, whereas ranking is cheap. This may not be true in reality in certain cases where ranking may be moderately expensive. In such situations, based on total cost considerations, k-tuple ranked set sampling is known to be a viable alternative, where one selects k units (instead of one) from each ranked set. In this article, we consider estimation of the distribution function based on k-tuple ranked set samples when the cost of selecting and ranking units is not ignorable. We investigate estimation both in the balanced and unbalanced data case. Properties of the estimation procedure in the presence of ranking error are also investigated. Results of simulation studies as well as an application to a real data set are presented to illustrate some of the theoretical findings. 相似文献
35.
Maria Carmen Iglesias-Pérez Jacobo de Uña-Álvarez 《Journal of statistical planning and inference》2008
In this paper we propose a new nonparametric estimator of the conditional distribution function under a semiparametric censorship model. We establish an asymptotic representation of the estimator as a sum of iid random variables, balanced by some kernel weights. This representation is used for obtaining large sample results such as the rate of uniform convergence of the estimator, or its limit distributional law. We prove that the new estimator outperforms the conditional Kaplan–Meier estimator for censored data, in the sense that it exhibits lower asymptotic variance. Illustration through real data analysis is provided. 相似文献
36.
李华荣 《山西高等学校社会科学学报》2008,20(9):30-32
柯亨认为,马克思主义追求的社会主义理想是消除资本主义的阶级剥削,代之以经济平等和彻底的民主,但是,从历史和现实看,我们都距离马克恩的理想有很大距离。即使作为当前的合理目标是最好的选择,市场社会主义至多仍然是次优的选择。鉴于历史发展的进程要求,即过渡特征,我们必须对结果意义上的各种不平等采取包容政策。但在社会主义机会平等的条件下,收入差异在仅仅反映了不同的收入、闲暇差异时才是可以接受的。社会主义平等并非“机械的平等”或“结果的相同”。 相似文献
37.
周学军 《西北民族大学学报》2008,(1):15-18
二世策墨林诺们罕是清代西藏著名活佛,原籍甘肃省洮州厅卓尼土司辖区,曾任西藏摄政(1819-1844)、第七十三任甘丹赤巴和十世达赖喇嘛的正师傅,是西藏历史上权势最大、结局最为悲惨的摄政活佛。道光二十四年(1844年)六月其被革职查办,拘禁拿问,次年(1845年)奉旨流放黑龙江,给披甲人为奴。国内外史学界对其最终结局、圆寂时间、圆寂地点、享年岁数及其呼毕勒罕三世策墨林活佛的出生年份历来众说纷纭。中国第一历史档案馆藏军机处录副奏折表明:成丰十年四月十九日(1860年6月8日),二世策墨林诺们罕活佛在新疆喀喇沙尔乌讷恩苏珠克图旧土尔扈特蒙古南部落的札萨克卓哩克图汗旗圆寂,享年69岁(1792-1860年),遗骨奉旨安葬于该旗境内的佑安寺(又称永安寺、巴伦台黄庙),其呼毕勒罕三世策墨林活佛出生于成丰十一年(1861年),而非其他年份。 相似文献
38.
Modeling for Risk Assessment of Neurotoxic Effects 总被引:2,自引:0,他引:2
The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels. 相似文献
39.
采用PCl-812PG数据采集卡,基于虚拟仪器技术,以Delphi作为平台开发了土壤含水量测试系统,对AZS -2土壤水分传感器的功能进行了扩展。标定结果及实际应用表明,此系统性能稳定,精度较高。 相似文献
40.
This paper deals with a single server Poisson arrival queue with two phases of heterogeneous service along with a Bernoulli schedule vacation model, where after two successive phases service the server either goes for a vacation with probability p (0≤p≤1) or may continue to serve the next unit, if any, with probability q(=1−p). Further the concept of multiple vacation policy is also introduced here. We obtained the queue size distributions at a departure epoch and at a random epoch, Laplace Stieltjes Transform of the waiting time distribution and busy period distribution along with some mean performance measures. Finally we discuss some statistical inference related issues. 相似文献