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241.
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A general framework to analyze communication media choice behavior in the university setting is proposed which integrates a stated preference experimental design procedure into a discrete choice modeling framework. The framework is empirically tested using hypothetical choice experiments in which traditional mail, courier mail, telephone, facsimile, and electronic mail services were choice options to carry out information communication tasks. For this purpose face-to-face interviews were conducted in six universities in Austria and Switzerland. The choice modeling approach developed emphasizes the influence of communication context specific characteristics, individual and organizational characteristics of the communication initiator as well as the individual's perceptions and feelings about the communication media on the formation of preferences. Empirical results are presented using stated preference models of communication media choice behavior for a series of communication situations. Specific emphasis is laid on cross-national differences in choice behavior.  相似文献   
243.
This article analyses the electoral support of the candidates of the Australian Country Party at Commonwealth (Senate) elections between the First and Second World Wars. It differs markedly, in terms of its premises, method and conclusions, from ‘orthodox’ analyses of the party's electoral support. Orthodox analyses state implicitly that rational (ie. goal‐directed, income‐maximising) considerations do not underlie the behaviour of the supporters of the Country Party; in contrast, I state explicitly that these considerations do underlie this behaviour. Further, orthodox analyses do not collect the evidence or data which they require in order to corroborate their claims; in contrast, I do so. Finally, unlike the Orthodox analyses, I specify as clearly as possible the techniques which I utilise in order to confront my data and hypotheses. I conclude that the behaviour of the supporters of the Country Party between the First and Second Wars is consistent with the postulate of rational behaviour, and that it is inconsistent with the arguments of orthodox studies.  相似文献   
244.
This paper1 investigates recent restructuring strategies of medium-sized firms in the Ruhr area, and assesses the role of institutional, organizational and socio-economic factors in shaping their strategic responses to economic change. By pointing out the extent to which embeddedness in different political-economic contexts constrains the expansion of organizational space, it is argued that medium-sized firms respond by falling back on routinized, predominantly regional, interaction structures. 'Embedding' and cooperation are, however, constrained by market forces and competitive pressures, which manifest themselves in various governance dilemmas. Solving these dilemmas between institutional persistence and 'economic imperatives' constitutes a major organizational challenge for the sample firms.  相似文献   
245.
A programming approach is presented for identifying the form of the weights matrix W which either minimizes or maximizes the value of Moran's spatial autocorrelation statistic for a specified vector of data values. Both nonlinear and linear programming solutions are presented. The former are necessary when the sum of the links in W is unspecified while the latter can be used if this sum is fixed. The approach is illustrated using data examined in previous studies for two variables measured for the counties of Eire. While programming solutions involving different sets of constraints are derived, all yield solutions in which the number of nonzero elements in W is considerably smaller than that in W defined using the contiguity relationships between the counties. In graph theory terms, all of the Ws derived define multicomponent graphs. Other characteristics of the derived Ws are also presented.  相似文献   
246.
Excavations at Acheulean sites in northern Europe at the end of the 19th century have yielded fossil sponges belonging to the Late Cretaceous species Porosphaera globularis. The spherical morphology of these fossils, their small size, and the presence of a natural complete perforation in their center have led some archaeologists to interpret them as the oldest known beads. Others argue that the presence of these fossils at archaeological sites is due to natural processes. Re-examination of material collected during the 19th century has recently revived the bead interpretation. We tested the bead hypothesis by analyzing 13 samples of Porosphaera from nine sites in Britain and France. We conducted morphometric and microscopic analyses on specimens recovered from archaeological sites (n = 349), a natural geological sample, which was collected directly from Cretaceous strata (n = 352), and a sample from a Bronze Age burial (n = 43). Reappraisal of contextual data shows that the association of these finds with Acheulean artifacts is uncertain. Our results show that archaeological specimens are significantly different in size and perforation pattern from those of the natural geological sample. This may be due to size-sorting caused by sedimentary processes, size-selection by Palaeolithic people or by 19th century collectors. Modifications of the fossils' natural shape were detected on a few specimens in the form of localized abrasions and microchipping along the hole margins. A single specimen displays a facet close to the hole produced by grinding. The surfaces of these features exhibit a hue lighter than that observed on the remainder of the specimens indicating that they may be recent in origin and due to post-excavation and preservation treatment. However, this seems contradicted, for some specimens from Bedford, by the fact that according to Smith, W.G. [1884. On a Palaeolithic floor at North-East London. Journal of the Anthropological Institute of Great Britain and Ireland 13, 357–384] the specimens bearing microchipping and abrasions were found by him and “not touched or manipulated by the workmen”. We conclude that new excavations of these sites, involving systematic screening of sediments, are needed in order to attempt to solve the Porosphaera “mystery”.  相似文献   
247.
'Yemen alabaster', a calcareous sinter, is a unique building and ornamental stone of the Sabaean culture ( c. 1000 BC to 100 AD). This study characterises the quarries and describes the facies of their stones. Through thin sections, luminescence microscopy and geochemical analyses, 'Yemen alabaster' can be classified and assigned a quarry source. The stone is a calcareous sinter related to volcanism in the Marib province. It can be divided into several microfacies types different in luminescence and trace element contents. During Sabaean times it was mined in highly organised quarries including underground quarries and used extensively in the Sabaean kingdom.  相似文献   
248.
For a long time historians have been discussing to what extent offshore routes were used in the ancient Mediterranean. In 20 years of almost annual expeditions we found Roman remains dating from different centuries around Keith Reef on Skerki Bank in the Strait of Sicily. These finds include material from several sunken ships as well as many single lead anchor-stocks. We conclude from our finds that a sizeable part of the traffic between Carthage and Rome followed a direct course across the sea.
© 2009 The Authors  相似文献   
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250.
This paper examines the trends in residential segregation by income (post-transfer, pretax income) in the thirty-nine largest Canadian urban areas between 1991 and 1996. The study is motivated by the relative lack of attention paid to residential segregation by income in the Canadian context and by conceptual arguments linking compromised life chances and increased social tensions for the populations of highly segregated cities. We investigated several dimensions of segregation using five different measures (we focus on three of these here given the correlation structure of the measures) to examine changes in segregation between 1991 and 1996, a period characterised by economic recession, cutbacks in social programs and a widening of inequality in market incomes at the national scale. Overall, income segregation increased in most urban areas across all dimensions of segregation during the time period, with particularly high degrees of segregation observed in prairie cities (Winnipeg, Saskatoon and Regina). Of the three largest metropolitan areas (Vancouver, Toronto and Montréal), Montréal was the most consistently segregated. We also find that increases in spatial separation and spatial concentration by income occurred despite the fact that at the national scale, the tax and transfer system appeared to be adequately redressing a rise in inequality in labour and market incomes (as demonstrated by the lack of change in post-transfer national income inequality measures during a period when inequality in market and labour incomes rose sharply). This implies that the lived experience of changes in income distribution are unlikely fully captured by aspatial, national-scale measures and that intra-urban measures with a spatial dimension are an important indicators of inequality in Canadian society.  相似文献   
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