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51.
《Journal of Natural History》2012,46(19-20):1333-1348
The taxonomy of the East African swallowtail Papilio hornimani is reviewed, with special reference to the three currently recognized subspecies described from the Usambara Mts (P. h. hornimani), Udzungwa Mts (P. h. mwanihanae) and the Oldeani‐Mbulu massif (P. h. mbulu), all located in Tanzania. The primary type material is illustrated, and type localities are established, notably with respect to the original source for P. h. hornimani, collected at Magila, Mlinga Forest area, East Usambara mountains. Populations from the Chyulu Hills (Kenya) and Mts Meru and Kilimanjaro (Tanzania), placed here with P. h. mbulu, appear to represent further potential segregates, or clinal variation. Prospects for conservation of the Mlinga Forest population are briefly discussed.  相似文献   
52.
从女权主义的视角出发解读美国著名作家约翰·斯坦贝克的短篇小说《紧身甲》。指出这种叙述中内在的性别歧视。分析了当时美国的父权社会、彼得以及作者本人对彼得的妻子艾玛的不公正,指出了艾玛才是真正的受压抑者。  相似文献   
53.
On the basis of evidence drawn from the Waste book, Westfall and Nicholas have argued that Newton arrived at his second law of motion by reflecting on the implications of the first law. I analyze another argument in the Waste book which reveals that Newton also arrived at the second law by another very different route. On this route, it is the consideration of the third law and the principle of conservation of motion—and not the first law—that prompts Newton to formulate the second law. The existence of these two routes is significant because each employs a distinct kind of reasoning about forces. Whereas the Nicholas-Westfall route via the principle of inertia bears the mark of Descartes’s influence, the alternative route proceeds from the action-reaction principle, which is widely regarded as an original Newtonian contribution to mechanics. In the course of exploring this alternate route to the second law, the origins and justification of the third law are examined.  相似文献   
54.
John Venn is known as one of the clearest expounders of the interpretation of probability as the frequency of a particular outcome in a potentially unlimited series of possible events. This view he held to be incompatible with the alternate interpretation of probability as a measure of the degree of belief that would rationally be held about a certain outcome based upon the reliability of testimony and other prior information. This paper explores the reasons why Venn may have been so opposed to the degree-of-belief interpretation and suggests that it may have been a way for him to resolve a conflict in his own mind between his ideas of proper scientific methods of inference and the religious beliefs that he held as a young man.  相似文献   
55.
I explain Locke’s account of the origin of our idea of power, showing that it concerns the idea of the disposition to act or change, and that this idea is constructed out of the ideas of action or change. I also show how Locke could have modified his account to avoid Hume’s criticism and argue that his neglect to do so reflects a studied neglect of taxonomy, an ambiguity in the notion of capacity, and complications in Locke’s conception of simple ideas. A comparison of the two empiricists reveals that not only do they disagree about the role of reason in the origin of our idea of power, but they are also talking about different ideas. Within the framework of Locke’s account of the origin of the idea of power, I explain why he believes that bodies only provide us with an obscure idea of active power. I conclude by defending his insight that there is a deep connection between the ability to predict and the idea of power.  相似文献   
56.
根据射孔完井电模拟以及Locke和Hong数值模拟研究的结果分析了射孔孔径、孔密及射入深度对表皮系数和油井产能的影响,发现使用和Locke曲线所得出的结果基本一致;曲线未考虑孔眼周围压实带的缺点,完全可以用近似公式修正。因为,实际上无法准确知道压实带的厚度及渗透率,准确地考虑这一因素是不可能的;曲线较现有的任何一种曲线都便于查找,至今仍在前苏联广泛使用,那种认为曲线已经过时的说法是缺少根据的,但扩大该曲线的范围和对压实带作修正则是需要的。  相似文献   
57.
格朗特与时间序列分析   总被引:1,自引:0,他引:1  
提出格朗特对时间序列分析的主要贡献与渊源关系:统计比率的稳定性恰是平稳时间序列的基础背景;差分思想、估计与预测的理念、对数据可信性的处理是格朗特现代时间序列的萌芽思想;分析了格朗特对皮尔逊的学术影响。  相似文献   
58.
神经生理学研究显示生物的智力生活与特殊神经中的细胞过程有着紧密的关联性。以此为依据,比克尔认为这些实验研究成果直接证明心理状态向分子生物学机制的还原。文章通过分析认为比克尔引用的长期记忆向细胞-分子机制的还原只能支持部分还原,并不支持他过强的整体性还原主张,因为实验事实证明分子通道既非长期记忆的充分条件,也非必要条件。  相似文献   
59.
On 29 May 1770 Joseph Banks described a spectacular swarming of ‘milions’ [sic] ‘of one sort’ of butterfly at Thirsty Sound, near what is now Rockhampton, Queensland, comparing it to a species from China that had been named by Linnaeus. Discovery of what appears to be an Endeavour voyage specimen of this Australian butterfly in the Hunterian Zoology Museum, Glasgow, allows us to confirm its long-suspected identity as Tirumala hamata hamata (Macleay) – a species unnamed and unknown at the time of Cook’s first voyage. Investigations into several collections that include eighteenth-century Australian Lepidoptera and associated literature have not positively identified any further specimens taken from the swarm, although a pair in the Oxford University Museum of Natural History could be from the same source. Taxonomic confusion due to mimicry, convergence and/or non-divergence affecting blue tiger patterned butterflies is most likely the principal reason such a specimen has previously gone undetected.  相似文献   
60.
自洛克以来,对个人同一性(Personal identity)的心理说明一直是种重要理论,依照这种理论,我们可以设想不同个体“互换身体”的情况,并且这种情况对心理说明提供了支持。当代学者伯纳德·威廉斯(Bernard Willianrs)对这种理论提出质疑,认为在说明个人同一性问题时,身体要素必不可少。威廉斯的质疑通过反驳互换身体的例子展开,本文将对威廉斯的反驳作出回应,指出该反驳存在的问题,以及为什么在说明我们的存在时,身体的必要性可能并不像威廉斯认为的那样确定。  相似文献   
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