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991.
992.
This study assesses the combined impact of multiple certifications (i.e. ISO 9001, ISO 14001, OHSAS 18001) on perceived performance dimensions related to quality, environmental and occupational health and safety. Using survey data collected from 59 Irish manufacturing plants in 2014, we employed MANCOVA and regression analysis to test our proposed hypothesis. The results suggest that companies that are simultaneously ISO 9001, ISO 14001 and OHSAS 18001 certified are significantly better performers with regard to environmental and occupational health and safety compared to companies without multiple certifications. However, from a perceived quality performance perspective, having these multiple certifications doesn’t seem to be an effective performance improvement tool. 相似文献
993.
994.
朱志勇 《宝鸡文理学院学报(社会科学版)》1999,(3)
思维运动主体不是人脑,而是从事社会实践的人。近代形而上学唯物主义把人脑看作是思维运动的主体,虽然肯定了思维运动主体的物质性,但却忽视了它的社会实践性。马克思主义哲学从实践出发理解现存世界和人的思维,把实践看作“人的思维的最本质和最切近的基础”,将从事社会实践活动的人确立为思维运动的主体,从而在思维运动主体上实现了物质性、实践性和社会性三者的有机统一。 相似文献
995.
996.
In pest risk assessment it is frequently necessary to make management decisions regarding emerging threats under severe uncertainty. Although risk maps provide useful decision support for invasive alien species, they rarely address knowledge gaps associated with the underlying risk model or how they may change the risk estimates. Failure to recognize uncertainty leads to risk‐ignorant decisions and miscalculation of expected impacts as well as the costs required to minimize these impacts. Here we use the information gap concept to evaluate the robustness of risk maps to uncertainties in key assumptions about an invading organism. We generate risk maps with a spatial model of invasion that simulates potential entries of an invasive pest via international marine shipments, their spread through a landscape, and establishment on a susceptible host. In particular, we focus on the question of how much uncertainty in risk model assumptions can be tolerated before the risk map loses its value. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. The results provide a spatial representation of the robustness of predictions of S. noctilio invasion risk to uncertainty and show major geographic hotspots where the consideration of uncertainty in model parameters may change management decisions about a new invasive pest. We then illustrate how the dependency between the extent of uncertainties and the degree of robustness of a risk map can be used to select a surveillance network design that is most robust to knowledge gaps about the pest. 相似文献
997.
The Freshwater Invertebrate Invasiveness Scoring Kit (FI‐ISK) is proposed as a screening tool for identifying potentially invasive freshwater invertebrates. FI‐ISK was adapted from the Fish Invasiveness Scoring Kit (FISK) of Copp, Garthwaite, and Gozlan, which is an adapted form of the Weed Risk Assessment (WRA) of Pheloung, Williams, and Halloy. Initial assessments using FI‐ISK, which include confidence (certainty/uncertainty) rankings by the assessor to each response, were calibrated to determine the most appropriate score thresholds for classifying nonnative species into low‐, medium‐, and high‐risk categories, using both the original medium‐to‐high risk threshold scores for the WRA (i.e., ≥6) and for FISK (i.e., ≥19). Patterns of the assessor's confidence, when making the responses during the FI‐ISK assessments, were also examined. Using receiver operating characteristic (ROC) curves, FI‐ISK was shown to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative crayfish (Decapoda: Astacidae, Cambaridae, Parastacidae), with the statistically appropriate threshold score for high‐risk species scores being ≥16. FI‐ISK represents a useful and viable tool to aid decision‐ and policymakers in assessing and classifying freshwater invertebrates according to their potential invasiveness. 相似文献
998.
We consider a continuous-time model for the evolution of social networks. A social network is here conceived as a (di-) graph on a set of vertices, representing actors, and the changes of interest are creation and disappearance over time of (arcs) edges in the graph. Hence we model a collection of random edge indicators that are not, in general, independent. We explicitly model the interdependencies between edge indicators that arise from interaction between social entities. A Markov chain is defined in terms of an embedded chain with holding times and transition probabilities. Data are observed at fixed points in time and hence we are not able to observe the embedded chain directly. Introducing a prior distribution for the parameters we may implement an MCMC algorithm for exploring the posterior distribution of the parameters by simulating the evolution of the embedded process between observations. 相似文献
999.
H.S. Konijn 《Australian & New Zealand Journal of Statistics》1990,32(3):313-316
For normal homoscedastic equicorrelated data the parameters μ, σ and p are identifiable, but it is shown that no consistent estimators exist. Confidence intervals for μ and prediction intervals with known confidence coefficients can, however, be obtained. 相似文献
1000.
This article examines the gender, setting, and degree of the first authors of published articles in JMFT from 1990 to 1995. Findings reveal that men are the first authors of 67% of the articles and women, 33%. PhDs are first authors on 58% of the articles, and authors in university settings write 53% of the published articles. Thirty-nine percent of the articles published during this period were research; 26%, clinical; 16%, theory; and 14%, training. Surprising findings were that MSW authors had a higher acceptance rate than PhDs, and authors in training institutes had a higher acceptance rate than those in university settings. 相似文献