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Chandra Mukerji 《History & Technology》2013,29(2):213-222
In 1783, Louis XVI founded the first public repository of machines in the very premises Vaucanson had set up his workshops the Hôtel de Mortagne. A record, found among the archives of the Conservatoire des arts et métiers, enables us to identify specimens which have been collected up to 1791 by this fairly unknown institution. While the existence of the public repository, established six months after Vaucanson's death, was attested to through the royal decree of August 2, 1783, the exact list of the machines and tools left by the engineer remained unknown. Furthermore, documents giving information on the activities of this institution, which was to be at the origin of the Conservatoire des arts et métiers, were rare. The inventory of the Hôtel de Mortagne sheds light on these two points. It is the second part of this hitherto unpublished document which appears below, following the summary of the text which preceeded the first part published in the previous issue of this journal. 相似文献
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This paper proposes a new spatial multivariate model to predict the count of new businesses at a county level in the state of Texas. Several important factors including agglomeration economies/diseconomies, industrial specialization indices, human capital, fiscal conditions, transportation infrastructure, and land development characteristics are considered. The results highlight the need to use a multivariate modeling system for the analysis of business counts by sector type, while also accommodating spatial dependence effects in business counts. 相似文献
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Christopher J. Cleal G.M. Bhat Kamal Jeet Singh A.M. Dar Anju Saxena Shaila Chandra 《Alcheringa: An Australasian Journal of Paleontology》2016,40(4):443-455
Cleal, C.J., Bhat, G.M., Singh, K.J., Dar, A.M., Saxena, A. & Chandra, S., February 2016. Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya. Alcheringa 40, xxx–xxx. ISSN 0311-5518.The Sepukhovian fossil floras of the northern margins of Gondwana, on the shores of the Palaeotethys, are dominated by remains of an eligulate, mainly monopodial lycopsid with persistent leaves. The stems show considerable morphological and preservational variation that has historically resulted in the fossils having been assigned to many fossil-species and -genera. However, there is now clear evidence that this simply reflects variation within a single fossil-species, reflecting biological variation and the effects of variable taphonomy, for which the correct taxonomic name is Spondylodendron pranabii (Pal) comb. nov. Part of this morphological variation might have been due to variations in growth rate during the life of the individual plants, which in turn might reflect stressed growing conditions in a wetland habitat. The systematic position of Spondylodendron remains uncertain, owing to the lack of unequivocal evidence of reproductive structures, but it might have affinities with the Sublepidodendraceae.Christopher J. Cleal [chris. cleal@museumwales. ac. uk], Department of Natural Sciences, National Museum Wales, Cathays Park, Cardiff CF10 3NP, UK; G.M. Bhat [bhatgm@jugaa. com] and A.M. Dar, Department of Geology, University of Jammu, Jammu, India; Kamal Jeet Singh, [kamaljeet31@hotmail. com] and Anju Saxena [anju_saxena2002@yahoo. co. in], Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, (U.P.) India; Shaila Chandra, Flat Number 105, Beverly Park Apartment 422, New Hyderabad, Lucknow-226007, (U.P.) India. 相似文献
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Siddharth Chandra 《Journal of regional science》2005,45(3):591-616
Abstract. The concept of economic homogeneity in regional science is based on two very different notions: composition and similarity. In the case of the states of the US, measures of homogeneity based on these different notions are negatively correlated with each other, suggesting that the results of studies that use measures of economic homogeneity are likely to be sensitive to the conceptual basis of the specific measure. In order to overcome this problem, a portfolio‐theoretic measure of economic homogeneity with some attractive properties is presented. It is naturally decomposable into two components reflecting each of these notions and easy to construct using widely available data. Using this measure, patterns of homogeneity for the states of the US are illustrated and discussed, and hypotheses about the relationship between homogeneity and economic instability are tested. 相似文献