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31.
The initial interpretations of motion phenomena are often in terms of eye movements. It reflects a desire to link an objective expression of motion (of the eyes) with a subjective experience of motion. This approach is examined historically with respect to induced motion, motion aftereffects, visual vertigo, autokinetic effects and stroboscopic motion. All but one of these phenomena were initially observed in the natural environment and they have subsequently been studied under laboratory conditions. Eye movements are not correlated with induced motion, the motion aftereffect, or stroboscopic motion, but they do correspond to the direction and extent of visual vertigo. The extent of apparent visual motion in the autokinetic effect far exceeds that of involuntary eye movements but there might be a weak relation between them. If eye movements are to provide a reasonable account of motion illusions then they should apply to all the contours that are visible. This does apply to visual vertigo, but not to induced motion, the motion aftereffect and stroboscopic motion, all of which involve relative motion in a visible display. The autokinetic phenomenon involves the perception of isolated stimuli, and so interpretations in terms of some internal eye movement signals remain sustainable.  相似文献   
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Much of the empirical research on urban sprawl has been carried out in North America and most theoretical studies on this problem have been concerned with expanding urban areas. This study differs, firstly in that it is concerned with sprawl in two European cities, Liverpool in England and Leipzig in Germany, and secondly because both these cities are in decline. This presents an opportunity to explore whether the process of urban sprawl is somehow specific in a situation of urban decline and what its outcomes might be for both urban form and urban policy.  相似文献   
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In this revised text of a lecture delivered at the Royal Institute of International Affairs in June 2003, Stanley Hoffmann traces the history of America's close postwar alliance with western Europe. Out of the treaty in which America undertook to protect western Europe came the organization of NATO. Despite the difficulties and differences of opinion among its members in the early years—decolonization, German rearmament, Vietnam, US—French relations—the alliance survived and continued to survive after 1991 despite losing its main enemy, the Soviet Union. It then became a tool for managing relations between members and the newly liberated countries of central and eastern Europe and Russia. After the first Gulf War, however, NATO became a field for US—European relations, encompassing rivalry over approaches to eastern Europe, and cooperation in the Balkans. September 11 and the 'war on terrorism' marked the real turning point in the alliance and the subsequent war in Iraq in 2003 exposed deep divisions in the approach to international relations. Stanley Hoffmann concludes that it is still unclear how far Iraq has affected the substance of US foreign policy and its relations with Europe. It may be possible to predict, however, that the central importance of Europe for the US will remain under a cloud—'the days of relative harmony have not returned'.  相似文献   
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After both the First and Second World Wars, the Polish state used nationality law as a tool for ethnic de-integration and dispossession, albeit in varying measure and with differing impact. After 1918, legislation and implementation focused less on economic interests than on those of the nation-state. Through the liquidation of private property against compensation, the German population, especially in Western Prussia, Poznań and Pomerelia, were to be persuaded to leave Poland voluntarily. These measures were within the legal framework set by the Versailles Treaties and the national tradition of civil law.  相似文献   
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We report here the first results of a method to extract and sequence mature enamel proteins from modern human and Neanderthal tooth enamel. Using MALDI-TOF/TOF mass spectrometry and a combination of direct sequencing and peptide mass mapping we have sequenced a peptide from the tyrosine-rich amelogenin peptide (TRAP) of the X isoform of the amelogenin protein for modern and recent human samples. We also report our results from two Neanderthal enamel samples where we were also able to recover fragments of the TRAP protein, which had a similar sequence to the modern human samples.  相似文献   
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We know compulsory voting is associated with higher levels of electoral turnout. It has been suggested that this leads to a trade-off with the quality of the vote, i.e. the ideological congruence between voters and the party they vote for. In this study, this claim is investigated using data from the 2007, 2010, and 2013 elections in Australia. We also include a comparison with two recent elections in Belgium, another country with compulsory voting. The results show that reluctant voters vote less ideologically congruent, but that this effect is mediated by political knowledge and political interest. However, this does not lead to less ideologically congruent election results at the aggregate level and compulsory voting does not have an impact on electoral results. We speculate that in future studies, it is important to make a distinction between reluctant voters, and those who take a strong hostile stand on the electoral process.  相似文献   
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