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81.
    
Frequently, in spatial interaction analysis, researchers are forced to use destinations that are zonal aggregates of the ‘real’ destinations perceived by the participants in the interaction process. Previous simulation studies demonstrated that, under certain circumstances, the aggregated spatial choice model can outperform the popular ordinary multinomial logit model, both in explanatory power and predictive ability. In this paper, the two models are compared with interprovincial migration microdata for the time period 1990-91, obtained from the 1991 Canadian census. Since this is not meant to be a migration study, the analysis is limited to out-migrants from Ontario. The results indicate that, at least with the data used, the multinomial logit model performed reasonably well. The paper, however, highlights some practical advantages that can accrue from the use of the aggregated model. Dans l'analyse de l'interaction à référence spatiale, il arrive fréquemment que les chercheurs soient contraints de se servir de destinations qui regroupent les?vraies?destinations perçues par les participants dans le processus d'interaction. Les études en simulations antérieures ont démontré que, dans certaines circonstances, le modèle groupé des choix à référence spatiale peut donner de meilleurs résultats que le modèle ordinaire commun du logit multinomial, sur le plan de la capacité d'explication comma sur celui de la valeur de prévision. Dans la présente étude, on fait la comparaison entre les deux modèles en utilisant les microdonnées sur l'émigration interprovinciale en 1990-91 obtenues par le recensement de 1991. L'analyse ne porte que sur les émigrants de l'Ontario puisqu'elle ne vise pas particulièrement l'étude de l'émigration. D'après les résultats, le modèle employant le logit multinomial fonctionne relativement bien, au moins avec les données utilisées. Toutefois, l'étude souligne certains avantages pratiques pouvant inciter à se servir davantage du modèle groupé.  相似文献   
82.
The original intention of the project, conceived in the context of the British School at Rome's excavation and survey programme in the Bradano basin (based on Gravina) was to establish the composition patterns of Hellenistic glazed wares from sites in southern Apulia, and then to use these to trace the trading patterns of the area, against a control group of sherds from the Athenian Agora. It proved possible to distinguish Attic from Apulian sherds by their nickel and chromium content, and average-link-cluster-analysis by computer showed that Gnathian ware from Taranto could be distinguished from seven other south Italian groups, suggesting that speciality wares were made of clays from special beds. Because of the geological homogeneity of the area no further distinctions could be made, but some sherds were also analysed petrologically and by heavy mineral analysis, for a methodological comparison. The very homogeneous geology, coupled with the fineness of the wares showed these methods to be at the limits of their usefulness. Only very generalized conclusions could be drawn concerning the origin of the pottery from the petrological evidence; the micro-mineralogical data showed that interesting differences existed between pottery from the main Apulian sites, but these could equally have reflected natural variations occurring within fairly homogeneous clay deposits.  相似文献   
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Attenbrow and Hiscock (2015) raise a series of concerns about the use of radiocarbon dates as data (sum probability distributions), including sample selection, taphonomic bias, and the relationship of charcoal and radiocarbon data to human activity. We show that these concerns have been widely acknowledged and addressed in the literature. We advocate the considered use of dates as data approaches as a heuristic tool for broad regional‐ and continental‐scale questions, used in conjunction with other archaeological proxies, and within the constraints of documented and well‐known methodological limitations.  相似文献   
85.
NATO has throughout its history been the subject of prognostications of crisis and dissolution. Indeed, the alliance has been written off so many times that crisis as normality has come to typify its development. In the twenty-year history of NATO's post-Cold War development, Operation Allied Force stands midway between the existential moment that was the collapse of the Soviet bloc and the current travails being experienced in Afghanistan. A comparison of NATO's experience in the Balkans and in the Afghan theatre suggests that the view of a NATO perched permanently at the edge of collapse is problematic and misleading. This is not to defend alliance actions as such but rather to suggest that the narrative of crisis and collapse makes for poor analysis and underestimates NATO's proclivity for adaptation and endurance.  相似文献   
86.
When the USA launched a military intervention in Grenada inOctober 1983 it was against the wishes of its closest ally,Britain, who felt deliberately misled as to Washington's intentions.As a former British colony and member of the Commonwealth, withthe Queen as Head of State, Grenada remained of interest toBritain. This article will provide a detailed analysis of Anglo-Grenadianrelations and the events and contacts between the USA and Britainduring and after the 1983 crisis and assess the role of the‘special relationship’ in shaping Britain's reactionto the intervention. I conclude that the conventional wisdomthat Britain was ‘in the dark’ about what was happeningis not entirely accurate. *The views expressed in this article represent those of theauthor alone.  相似文献   
87.
NATO moves toward its next summit (to be held in Newport, Wales in September 2014) in a mood of anxiety and uncertainty. This is not simply because telling questions are being asked of the alliance in relation to Afghanistan and Ukraine, but because the twin motors which have sustained NATO now show signs of considerable wear and tear. The first of these motors relates to principles of purpose. This encompasses the activities (or purposes) which NATO has consciously pursued in the last 25 years: namely, operations, enlargement, partnership, transatlanticism and security. The second is principles of function: the means, in other words, by which NATO is kept in motion. Here, American leadership, cohesion and trust, burden‐sharing and credibility all matter. These motors are not about to completely break down (NATO has underlying strengths which make that unlikely) but they do need attention. NATO's good health requires it to focus on a series of core tasks—what this article refers to as readiness, reassurance and renewal. These three tasks speak to an agenda of consolidation and preservation, rather than one of task expansion. But this is not a conservative agenda; grasping the nettle of prioritization and focus requires, in itself, a certain foresight and enterprise. Managed successfully, it is an agenda that will preserve and strengthen NATO in what are increasingly troubled times.  相似文献   
88.
This review article examines four recent books that explore how international peacekeepers have coped with the challenges of state-building and regionalization. Two volumes analyse the pitfalls and prospects of international attempts to turn war-shattered states into stable market democracies, while two volumes explore the problems and opportunities thrown up by attempts to forge effective working relationships between the United Nations and regional arrangements in Europe, Africa and beyond. The review concludes that although state-building is most legitimate when conducted under the auspices of the UN, the organization's almost permanent condition of overstretch and the US-led 'war on terrorism' have undermined its practical ability to lead such operations. It also suggests that the current approach to regionalization is unlikely to provide panacea for state-building or more general peacekeeping problems.  相似文献   
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Cardinal Patrick Moran, the Catholic Archbishop of Sydney 1884–1911, believed that Australian Catholicism would flourish with the emergence of the new nation through Federation in 1901, provided that Australians turned away from foreign influences, including anarchism and nihilism. Moran also sought to use Australia to "Christianise" the enormous population of China, and believed that Chinese immigration could make a useful contribution to nation building. As the nineteenth century closed, Moran's aims were also complicated by the more insidious threats represented by a challenge to religious faith by fin de siècle ideas — a modernism manifesting as both a general challenge and a specific doctrinal relativism that might erode the Church's authority, and the threat Moran felt was posed to the development of the liberal Australian state and the Catholic Church by radical political alternatives. Concern that a mood of religious apostasy and secularisation might spread to the Catholic community also influenced Moran's support for the fledgling Australian Labor Party, which Moran believed could develop as an instrument to reinforce a moral and inclusive sense of Australian identity for the Catholic working class. Like his pro-Chinese views, Moran's advocacy of "the rights and duties of labour" was defined by an imagined alliance of evangelism and nation building, stimulated by the fear, as he expressed in 1891, of "an unchristianized world."  相似文献   
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