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161.
162.
This paper studies the effects of non-normality and autocorrelation on the performances of various individuals control charts for monitoring the process mean and/or variance. The traditional Shewhart X chart and moving range (MR) chart are investigated as well as several types of exponentially weighted moving average (EWMA) charts and combinations of control charts involving these EWMA charts. It is shown that the combination of the X and MR charts will not detect small and moderate parameter shifts as fast as combinations involving the EWMA charts, and that the performana of the X and MR charts is very sensitive to the normality assumption. It is also shown that certain combinations of EWMA charts can be designed to be robust to non-normality and very effective at detecting small and moderate shifts in the process mean and/or variance. Although autocorrelation can have a significant effect on the in-control performances of these combinations of EWMA charts, their relative out-of-control performances under independence are generally maintained for low to moderate levels of autocorrelation.  相似文献   
163.
学习是人类社会永恒的主题。为了更好地利用过去的经验,增强学习效果,个人和组织进行学习迁移具有重要意义。学习迁移是指将在以往通过学习或解决问题所获得的经验,用于解决之后所遇到的问题。本文力图建立系统的学习迁移理论,研究人、问题、环境的因素对于学习迁移的影响。本文采用理论推导的研究方法,在前人研究的基础上,提出相应的理论模型。本文运用系统的观点,构建了学习迁移的PPEE理论模型,认为人的因素、问题的因素、人和问题的交互作用、以及环境的调节作用,会共同影响学习迁移的效果。本理论主要从五个方面论述学习迁移的机制。首先,将人的因素按照不同层面划分为后端基本能力、中端心理过程、前端知识结构,讨论了其各自对学习迁移效果的直接影响。其次,将问题的因素划分为形象相似性和抽象相似性,并根据这两个维度构建了四种问题间关系类型,并探究了其与学习迁移效果之间的关系。第三,同时考虑人的因素和问题的因素,研究了二者之间的互动对于学习迁移效果的影响。第四,将环境因素划分为时间紧迫性和空间重要性两个维度,探讨了人和环境,以及问题和环境之间的互动对学习迁移效果的影响。第五,基于系统整体的方面,研究人、问题、环境三者之间的互动对学习迁移效果的交互影响。本文还认为,该模型不仅适用于个人,也同样适用于团队、组织、地区、甚至国家和社会等各个层面,影响各个层面主体的学习迁移。本文最后总结了研究的理论和实践贡献,并提出了未来研究课题。本文对丰富学习理论、特别是学习迁移理论,以及推动教育和管理实践的发展进步具有重要的意义。  相似文献   
164.
Self-report purchase tasks are a novel approach examining the reinforcing value of addictive behaviour relative to increasing monetary costs required to access the addictive behaviour (i.e. demand). These measures reveal a positive relationship between the indices of demand and addiction problem severity and can elucidate factors associated with motivation for substance use. Gambling is an addictive behaviour that has not been examined using this paradigm. This study seeks to adapt and examine the purchase task for gambling behaviour. A gambling purchase task was devised that asked individuals how often per month they would gamble at various cover charges. Participants were 73 adults from the community with either gambling disorder (n = 28) or alcohol use disorder (n = 24) or were a healthy control (n = 21). Both the alcohol and gambling purchase tasks were administered. Results demonstrate discriminant validity of the gambling purchase task, as individuals with gambling disorder have significantly greater demand for accessing gambling than other groups. The alcohol purchase task also evidenced discriminant validity in that individuals with alcohol use disorder have significantly greater demand for alcohol than other groups. These findings support the use of the gambling purchase task to assess the demand for gambling.  相似文献   
165.
The star-shaped Λ-coalescent and corresponding Λ-Fleming–Viot process, where the Λ measure has a single atom at unity, are studied in this article. The transition functions and stationary distribution of the Λ-Fleming–Viot process are derived in a two-type model with mutation. The distribution of the number of non-mutant lines back in time in the star-shaped Λ-coalescent is found. Extensions are made to a model with d types, either with parent-independent mutation or general Markov mutation, and an infinitely-many-types model, when d → ∞. An eigenfunction expansion for the transition functions is found, which has polynomial right eigenfunctions and left eigenfunctions described by hyperfunctions. A further star-shaped model with general frequency-dependent change is considered and the stationary distribution in the Fleming–Viot process derived. This model includes a star-shaped Λ-Fleming–Viot process with mutation and selection. In a general Λ-coalescent explicit formulae for the transition functions and stationary distribution, when there is mutation, are unknown. However, in this article, explicit formulae are derived in the star-shaped coalescent.  相似文献   
166.
战后非殖民化运动导致印度尼西亚和苏里南大量人口移居荷兰;20世纪50年代中期开始到70年代初,荷兰从地中海沿岸国家输入大量劳工,随后劳工移民带来大量家庭移民;80年代中期以后,难民以及寻求庇护者纷纷进入荷兰,成为荷兰移民的重要部分。随着类型多样、来源广泛的移民不断进入,荷兰的人口结构发生重大改变,大量外来移民的存在,尤其大量穆斯林人口的存在,成为荷兰社会面临的重要问题。  相似文献   
167.
168.
The mean residual life measures the expected remaining life of a subject who has survived up to a particular time. When survival time distribution is highly skewed or heavy tailed, the restricted mean residual life must be considered. In this paper, we propose an additive–multiplicative restricted mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline. For the suggested model, some covariate effects are allowed to be time‐varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness of fit test that is asymptotically justified. The proposed methodology is evaluated via simulation studies and further applied to a kidney cancer data set collected from a clinical trial.  相似文献   
169.
In this study, we propose an information measure of uncertainty associated with the random equilibrium residual lifetime of a system driven by N-State Random Evolution. A U-statistic test driven by a moment inequality is proposed for testing the hypothesis that the uncertainty of equilibrium remaining life of a system remains unchanged (when system is in the steady state) against the alternative situation when system’s equilibrium residual life has increasing uncertainty over time (i.e., the life distribution has Increasing Equilibrium Residual Entropy property). Some numerical results such as tabulated critical values and empirical power of the proposed test statistic are presented as well.  相似文献   
170.
The Best Worst Method (BWM) is a multi-criteria decision-making method that uses two vectors of pairwise comparisons to determine the weights of criteria. First, the best (e.g. most desirable, most important), and the worst (e.g. least desirable, least important) criteria are identified by the decision-maker, after which the best criterion is compared to the other criteria, and the other criteria to the worst criterion. A non-linear minmax model is then used to identify the weights such that the maximum absolute difference between the weight ratios and their corresponding comparisons is minimized. The minmax model may result in multiple optimal solutions. Although, in some cases, decision-makers prefer to have multiple optimal solutions, in other cases they prefer to have a unique solution. The aim of this paper is twofold: firstly, we propose using interval analysis for the case of multiple optimal solutions, in which we show how the criteria can be weighed and ranked. Secondly, we propose a linear model for BWM, which is based on the same philosophy, but yields a unique solution.  相似文献   
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