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The extant literature highlights numerous different factors influencing the timeliness and intensity of incumbent response to discontinuous technological change. However, this literature has so far not been synthesized and is therefore limited in its analytical, predictive, and normative power. We develop a comprehensive model of incumbent response that organizes different explanatory factors into the three distinct dimensions of (1) identification and interpretation, (2) decision making, and (3) organizational implementation. We also conceptualize how response intensity and timeliness affect business performance in new technological domains. We test the model against data from 320 firms from the German dental lab industry, finding substantial support for the majority of our hypotheses. This study offers unique empirical insight in observing that cognitive constructs such as framing and management flexibility have the strongest impact on both intensity and timeliness of incumbent response to technological, and thus, strategic discontinuities. Together, our findings have important implications for both theory and practice.  相似文献   
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The concept of distribution form developed in Brenner and Fraser (1980) is modified and extended to cover the more general context involving a class of distribution for form. This extension underlies the choice of a particular structural model for the three-parameter Weibull in Evans, Fraser and Massam (1982). The extended definition of distribution form is based on the requirement of objectivity in modelling (Fraser 1979). Three characterizations of this objectivity each require that the class of response presentations have closure under composition and thus be expressible in terms of a group. In particular, this implies that empirical support would not observationally be available for that generalization of a structural model called astructured model (Fraser 1972; the term functional model has been used inappropriately by Bunke, 1975 and Dawid and Stone, 1982).  相似文献   
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Urban areas consist of wide expanses of impervious surfaces which are known to negatively affect insect biodiversity in general, but green spaces within cities have the potential to provide necessary habitat and foraging resources. Although, communal gardens were primarily intended to provide fresh, regional food to denizens, these green islands also host a surprisingly high number of wild bee species.

The gardens were characterized based on structural elements such as flower frequency, the relative percentage of lawn, trees, shrubs, planted crops and infrastructure (e.g. seating possibilities or garden houses). Further, the effects of different landscape structures surrounding the gardens and distance to the city center were analyzed on the total wild bee species richness and functional traits. Focusing on these putative influencing factors, statistical analyses calculating random decision forests along with generalized linear mixed models were applied. With 113 observed wild bee species, communal gardens provide habitat for a quarter of all known species in Vienna. In conclusion, results revealed that only elements within the gardens had an effect on species richness, with flower frequency as the major positive driver. The examined communal gardens promote and conserve wild bees independent from the location within the city or garden size. Furthermore, these green patches are important sanctuaries, hosting rare and threatened species as well as remarkably special wild bee communities.

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In this study, we construct a multivariate model that assesses the risk of an outbreak of civil war in a country over a period of 5 years into the future. In addition to structural factors of state weakness, which have dominated the literature on civil war onset, this model includes repression of basic human rights to personal integrity – an important harbinger of wars to come – as an aspect of state behavior. Our aim is not to explore the causal factors of civil war onset, but to build a model that includes indicators that correlate with civil war outbreak and may be used to predict it. Based on two versions of the model – logit and neural network – out-of-sample risk assessments for three different time periods are generated and compared to the historical record of civil war outbreak during those years. In addition, the model’s ability to produce in-sample risk assessments over a 5-year period is tested. Finally, we compute truly predictive civil war risk assessments for all countries for which data are available, for the years 2008–2012. The analyses show that with a relatively simple model and based on publicly available data sources, meaningful civil war risk assessments can be computed. The quality of the predictions exceeds that of prominent studies, in which the risk of interstate war is assessed.  相似文献   
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The paper discusses a simulation method for multivariate Gaussian time series by means of the discrete Fourier transform (Borgman, 1982). The procedure is quite general with respect to the correlation and spectral properties of the series and allows In addition simulations conditional on a subset of the time series. Simulations of the output from a set of ocean wave recorders are shown as an illustration of the method.  相似文献   
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Discusion     
Resumen

En esta investigación se estudia la validez de una versión castellana de la escala «Environmental Concern Scale» (ECS) llevada a cabo con 716 estudiantes. Las puntuaciones obtenidas por los sujetos proambientalistas y no proambientalistas resultan significativamente diferentes. Asímismo, se estudian las relaciones entre las actitudes hacia la preocupación por el medio ambiente, la energía nuclear y la ideología política, mostrándose una relación entre ellas de diferente intensidad. Mientras la energía nuclear está fuertemente vinculada a la ideología política, no sucede en tal medida entre ésta y las actitudes conservacionistas, ya que tanto los de derechas como los de izquierdas participan de la preocupación por el medio ambiente, aunque no en la misma medida.  相似文献   
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