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41.
基于发展新理念对粮食类家庭农场成长绩效的评价指标进行理论遴选后,借助专家评审和鉴别力分析进行指标筛选,构建了具有较高信度和效度的评价指标体系。以华北平原五省的453户粮食类家庭农场为样本,采用AHP-模糊综合评价模型,对指标体系做了应用研究。结果表明:粮食类家庭农场成长绩效虽在总体上处于中等偏上水平,但个体间存在一定的成长绩效差异;经济绩效整体表现良好,创新绩效却较低。因此,应引导粮食类家庭农场平衡性成长、制定精准扶持方略和建立成长绩效监测体系。  相似文献   
42.
靳力 《学术界》2012,(6):67-74,284
政府规模与经济增长之间的关系问题是宏观经济研究中的核心问题之一.关于两者关系的传统研究往往以线性假定为基础,所以实证结果出现了巨大的差异.这种现象促使研究者从非线性角度重新审视政府规模与经济增长之间的关系.“巴罗法则”在内生增长框架内为政府规模与经济增长关系研究提供了一个标准的分析框架,揭示了两者之间的倒“U”关系.而“Armey曲线”不仅非常直观地表达了政府规模与经济增长之间的非线性关系,同时还指出这种非对称关系的非对称性质,具有很强的总结性和政策指导意义.  相似文献   
43.
Kleinbaum (1973) developed a generalized growth curve model for analyzing incomplete longitudinal data. In this paper the small sample properties of several related test statistics are investigated via Monte Carlo techniques. The covariance matrix is estimated by each of three non-iterative methods. The null and non-null distributions of these test statistics are examined.  相似文献   
44.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.  相似文献   
45.
Nonparametric models with jump points have been considered by many researchers. However, most existing methods based on least squares or likelihood are sensitive when there are outliers or the error distribution is heavy tailed. In this article, a local piecewise-modal method is proposed to estimate the regression function with jump points in nonparametric models, and a piecewise-modal EM algorithm is introduced to estimate the proposed estimator. Under some regular conditions, the large-sample theory is established for the proposed estimators. Several simulations are presented to evaluate the performances of the proposed method, which shows that the proposed estimator is more efficient than the local piecewise-polynomial regression estimator in the presence of outliers or heavy tail error distribution. What is more, the proposed procedure is asymptotically equivalent to the local piecewise-polynomial regression estimator under the assumption that the error distribution is a Gaussian distribution. The proposed method is further illustrated via the sea-level pressures.  相似文献   
46.
Bayesian acceptance sampling plans, which utilize prior information on the process variation, can be employed as an alternative to conventional types of plans for taking decisions on the disposition of submitted lots. A special type of double sampling inspection plans by attributes with small acceptance numbers using Bayesian methodology is presented in this paper emphasizing its significance over small acceptance number single sampling plans. The procedures for designing such sampling plans for specified degree of discrimination which would ensure protection to the producer and consumer are discussed with illustrations under the conditions for the application of gamma-Poisson distribution.  相似文献   
47.
由于语言自身的特点和语境的需要,政治文本中有大量的模糊表达法。如何翻译这些表达法,对于提高译本的可接受性及准确传达说话人的意思、实现交际目的,具有重要意义。本文将模糊语言分为模糊句子、模糊限制语、模糊词语三种类型,分析中央编译局提供的《十八大报告》英文译本,发现每一种类型的模糊语都有多种译法,但总体原则是让译文符合译入语习惯和实现说话人的交际意图。  相似文献   
48.
This study investigated differences in the trajectory of marital satisfaction in the first 7 years between couples in covenant versus standard marriages. The authors analyzed data on 707 Louisiana marriages from the Marriage Matters Panel Survey of Newlywed Couples, 1998–2004, using multivariate longitudinal growth modeling. When the sample was restricted to couples who remained married over the duration of the study, a marginal benefit of covenant status was found for husbands. This effect was largely accounted for by covenant husbands' more extensive exposure to premarital counseling. The linear decline in marital satisfaction over time that obtained for both husbands and wives was not, however, any different for covenant marriages versus standard marriages. Couples characterized by more traditional attitudes toward gender roles were significantly less satisfied than others. High premarital risk factors, initial uncertainty about marrying the spouse, and the presence of preschool‐age children in the household were all corrosive of marital satisfaction at any given time.  相似文献   
49.
模糊理论使人们认识到语言模糊性的客观存在。模糊性是语言的自然属性。在翻译中,对于语言模糊性的认识,是正确理解原文并用译文准确表达的基础。在翻译教学中,教师应该指引学生识别和运用模糊语言,从而有效地从整体上提升学生的翻译能力。  相似文献   
50.
迄今,为解决多属性偏好关联决策属性集容量判断指数复杂性难题所提出的λ模糊测度模式与k-可加模糊测度模式,以及建构在它们之上的属性集容量确定的推算模型,尚存在着适用性差的技术不足。为此,以平衡容量判断的可操作性和容量推算的准确性为视角,提出了一种新容量测度模式,即关于容量判断与推算的夹挤式测度模式,并在此基础上通过引入决策者较易判断给出的容量序信息构建了相应的容量推算模型。基于数值模拟的对比分析表明:新模式不仅在应用可行性上高于k-可加模糊测度模式,而且从容量推算的准确性上看也明显优于λ模糊测度模式和k-可加模糊测度模式,因而对实际决策具有更强的适用性。  相似文献   
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