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71.
作为一种全新的教育理念,融合教育自提出以后很快成为国际特殊教育的发展趋势。当前,我国融合教育在取得巨大进步的同时,在融合主体的接纳态度与行动支持、教师专业能力与合作意识、融合课程与教学、融合资源投入与共享等方面仍然面临困境。基于共生理论视角对融合教育困境进行理论反思,提出构建融合共生的社会文化环境、建立教师专业学习社群、调整课程与教学、完善资源配置等建议,以期为推进融合教育、提升融合教育质量提供借鉴。  相似文献   
72.
农村集体经济是实现我国农村产业发展和农民共同富裕的有效途径,是完善社会主义市场经济体制发展的内在要求.秦巴山区城口县在家庭承包制下,不断探索和创新农村集体经济实现形式,建立起以"农户入社、社企合作"的新型农村集体经济组织形式——双层股份合作制.通过对双层股份合作制模式的分析,认为它是一种既实现效率又兼顾公平的新型农村集体经济组织形式,对国家实现扶贫攻坚和地区脱贫致富有着重要意义.  相似文献   
73.
随着中国单身人口比例的上升,单身人群特别是单身女性群体受到了社会各个层面的关注。目前国内对单身女性的研究主要通过深度访谈来探讨单身未婚女性的身心和生活状态,缺乏系统的理论观照,且访谈样本又大都局限于大城市的中产阶层单身未婚女性,因而限制了研究成果的代表性。从交叉性理论出发,分析中国单身女性面临的宏观(儒家文化和人口调控压力)、中观(媒体的形象控制和代际压力)和微观(性别歧视、年龄歧视和单身歧视)的多元交叉压力和歧视,厘清目前单身女性所受到的压力和歧视,从不同阶层单身女性的需求出发,才能为她们提供切实有效的帮助,并有助于解决目前我国单身人口比例上升的问题,缓解人口老龄化的压力。  相似文献   
74.
The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure.  相似文献   
75.
在网络技术发达的时代,远程高等教育是世界高等教育发展的必然趋势。中国为了跟上时代的步伐,有必要大力发展远程高等教育。由于中国远程高等教育发展的时间短,技术水平低,因此有必要向发达国家学习。澳大利亚具有发展远程高等教育的悠久历史,发展水平也处在世界前列。因此,借鉴澳大利亚远程高等教育的发展经验,对中国远程高等教育的发展具有重要的启示。  相似文献   
76.
Of the 324 petroleum refineries operating in the U.S. in 1982, only 149 were still in the hands of their original owners in 2007. Using duration analysis, this paper explores why refineries change ownership or shut down. Plants are more likely to ‘survive’ with their original owners if they are older or larger, but less likely if the owner is a major integrated firm, or the refinery is a more technologically complex one. This latter result differs from existing research on the issue. This paper also presents a split population model to relax the general assumption of the duration model that all refiners will eventually close down; the empirical results show that the split population model converges on a standard hazard model; the log-logistic version fits best. Finally, a multinomial logit model is estimated to analyze the factors that influence the refinery plant's choices of staying open, closing, or changing ownership. Plant size, age and technology usage have positive impacts on the likelihood that a refinery will stay open, or change ownership (rather than close down).  相似文献   
77.
In survival analysis, it is routine to test equality of two survival curves, which is often conducted by using the log-rank test. Although it is optimal under the proportional hazards assumption, the log-rank test is known to have little power when the survival or hazard functions cross. To test the overall homogeneity of hazard rate functions, we propose a group of partitioned log-rank tests. By partitioning the time axis and taking the supremum of the sum of two partitioned log-rank statistics over different partitioning points, the proposed test gains enormous power for cases with crossing hazards. On the other hand, when the hazards are indeed proportional, our test still maintains high power close to that of the optimal log-rank test. Extensive simulation studies are conducted to compare the proposed test with existing methods, and three real data examples are used to illustrate the commonality of crossing hazards and the advantages of the partitioned log-rank tests.  相似文献   
78.
河北省涉县旱作梯田系统是中国重要农业文化遗产。 其核心保护区域王金庄村位于太行山东麓,地形条件复杂,缺土少水、旱涝频发,但梯田系统因独特的人文智慧延续近八百年而不衰。 文章以水为切入点,阐释水资源短缺情形下百姓的生存逻辑与生计策略。 村庄作为一个系统对自然环境进行着补救性适应、抗风险适应与常态适应,这些文化适应性举措使旱作梯田的可持续发展得以实现,也展示出古老农耕智慧对于农业永续发展的重要意义。 因此,保护农业文化遗产不仅是对传统文化与社会系统的保护,更是对现代农业后果的生态补救,对农业与农村发展的现实反思,对可持续发展之路的探寻。  相似文献   
79.
This paper considers the optimal design problem for multivariate mixed-effects logistic models with longitudinal data. A decomposition method of the binary outcome and the penalized quasi-likelihood are used to obtain the information matrix. The D-optimality criterion based on the approximate information matrix is minimized under different cost constraints. The results show that the autocorrelation coefficient plays a significant role in the design. To overcome the dependence of the D-optimal designs on the unknown fixed-effects parameters, the Bayesian D-optimality criterion is proposed. The relative efficiencies of designs reveal that both the cost ratio and autocorrelation coefficient play an important role in the optimal designs.  相似文献   
80.
Wang  Dewei  Jiang  Chendi  Park  Chanseok 《Lifetime data analysis》2019,25(2):341-360

The load-sharing model has been studied since the early 1940s to account for the stochastic dependence of components in a parallel system. It assumes that, as components fail one by one, the total workload applied to the system is shared by the remaining components and thus affects their performance. Such dependent systems have been studied in many engineering applications which include but are not limited to fiber composites, manufacturing, power plants, workload analysis of computing, software and hardware reliability, etc. Many statistical models have been proposed to analyze the impact of each redistribution of the workload; i.e., the changes on the hazard rate of each remaining component. However, they do not consider how long a surviving component has worked for prior to the redistribution. We name such load-sharing models as memoryless. To remedy this potential limitation, we propose a general framework for load-sharing models that account for the work history. Through simulation studies, we show that an inappropriate use of the memoryless assumption could lead to inaccurate inference on the impact of redistribution. Further, a real-data example of plasma display devices is analyzed to illustrate our methods.

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