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71.
俱乐部的性质与最佳规模研究   总被引:1,自引:0,他引:1  
本文旨在对公共选择学派的俱乐部理论做一简要介绍并将其引入到俱乐部的经营管理当中;借助俱乐部经济理论分析了俱乐部的性质,介绍了俱乐部会员的流动经营模式,并探讨了俱乐部最佳规模的界定模型,包括布坎南的“内俱乐部理论”与蒂博特的“用脚投票”理论。  相似文献   
72.
Terrestrial reptile remains are very rare in the Lower Cretaceous of South Australia, but include the holotype of the small theropod Kakuru. Here, we review this taxon and other archosaur specimens collected from the Bulldog Shale (Aptian) of Andamooka and Coober Pedy. Kakuru possesses no unique characters or character state combinations and is regarded as a nomen dubium, representing an indeterminate tetanuran theropod. Two other specimens (a left metatarsal and astragalus) can be referred to Dinosauria, but the identity of several other specimens (phalanges and a centrum) can only be resolved to the level of an indeterminate archosaur.  相似文献   
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The Yuzhen Palace is one of the nine palaces in the Ancient Building Complex built by order of the Yongle Emperor during the Ming dynasty. The buildings were built with dressed black bricks. As a result of the planned national South–North Water Diversion project, the water level in the Danjiangkou Reservoir that surrounds the Yuzhen Palace was expected to rise by approximately 15 m. To avoid submersion of the site, three gates were elevated by 15 m in 2013 and other buildings dismantled, for later reconstruction. The characterization of the construction materials has therefore become of primary importance. Here, we present results on the plasters of the Longhu Hall. The analysis of materials involved a multi‐analytical approach combining optical and electron microscopy with X‐ray and vibrational spectromicroscopies and thermogravimetry. The results indicated the use of two earthen plaster layers and a whitewash finish coating applied over a thin preparatory intermediate layer to improve the adherence of the finish coating to the earthen plaster. Ramie and straw fibres identified in the earthen plasters were added to reduce shrinkage and cracking during drying. The raw materials used and the application technique pointed to a well‐established construction industry using traditional earthen building materials together with lime technology.  相似文献   
75.
Samples of celadon were collected from the Altar Guan Kiln in Hangzhou, and from the Xiaomeizhen and Xikou Kilns, two subordinate kilns of the Longquan Kiln producing black‐body celadon called Literature Ge. Both the elemental contents in the sample bodies and the glaze were measured. The results reveal that the sample bodies contain fingerprint information for provenance, while this was lost in the glaze during the production process. The TiO2, MnO and Rb2O contained in the bodies are fingerprints to distinguish between celadons from the Xiaomeizhen and Xikou Kilns. In the Altar Guan Kiln, some low‐TiO2 samples were found and their body colour is much lighter than some others, but they do not differ with regard to iron content. This indicates that both titanium and iron are indispensable for the blackness of the bodies: they may react to form some black minerals during the firing process. Ultimately, samples from the Literature Ge and Altar Guan Kilns differ in their body constituents. Principal component analysis reveals that the samples can be divided into two groups, corresponding to the two different areas.  相似文献   
76.
X. Zong  X. Y. Wang  L. Luo 《Archaeometry》2018,60(5):1088-1105
This paper is focused on the joint use of non‐invasive and minimal intervention techniques for supporting archaeological prospection. Very high resolution (VHR) satellite imagery analysis and ground‐penetrating radar (GPR) and boring surveys were integrated for the study of the Longcheng site, located near Hefei city in Anhui Province, China, to test their effectiveness and efficiency in prospecting archaeological remains and evaluating their degree of preservation. First, target locations of potential archaeological structures were identified on a WorldView‐2 (WV‐2) satellite image through spatial and radiometric enhancement, interpretation and object‐oriented classification. Second, archaeological features extracted from the WV‐2 imagery were further investigated by a GPR survey that provided detailed cross‐checking information about buried remains. Finally, a subsequent boring survey was conducted across those prospective archaeological structures in order to map the stratigraphic sequences on the basis of colour, compactness and the inclusions contained in the soil, and then to test their correspondence with the GPR data. The boring led to detailed confirmation of the results produced by the remote sensing analyses and GPR surveys, as well as the discovery of datable artefacts. On the basis of all the integrated data, the preliminary layout and structure of the Longcheng site was reconstructed in GIS. Furthermore, the widths, lengths, heights and burial depths of these buried archaeological structures were estimated in detail.  相似文献   
77.
Tanzania's endangered heritage: A call for a protection program   总被引:1,自引:0,他引:1  
There is no doubt that heritage resource loss in Tanzania is proceeding at an alarming rate. Natural and human agencies, adverse storage infrastructures and techniques, and lack of trained conservators and curators and of a proper protection program are the major threats that endanger the heritage resources of Tanzania. As our natural and cultural environments bring irreparable damage to the resources that document our human history, we need to preserve and protect them before they vanish. A preservation and protection program for Tanzania should include public education, the establishment of heritage preservation laws, more progress in the inventory and protection of in situ heritage resources, research into preservation and conservation methods, training of staff, and improvements in the curation of collected heritage resources and records. Preservation and protection of heritage resources are collaborative exercises. The scientific and world community need to support and engage in this proposed program both technically and financially, if the preservation and protection of heritage resources in Tanzania are to succeed.
Résumé Il ne fait pas de doute que la perte des ressources du patrimoine historique se poursuit à un rythme alarmant en Tanzanie. Les agents naturels et humains, des techniques et des locaux de conservation inadaptés, el manque de conservateurs bien formés et d'un programme de sauvegarde adéquat sont les principales menaces qui pèsent sur les biens historiques et culturels en Tanzanie. Comme notre environnement naturel et culturel provoque des dommages irréparables aux sources historiques, nous devons les préserver et les protéger avant qu'elles ne disparaissent. Un programme de préservation et de protection pour la Tanzanie devrait inclure l'éducation du public, l'adoption de lois relatives à la sauvegarde du patrimoine, de nouveaux progrès dans l'inventaire et la protection in situdes vestiges, des recherches sur les méthodes de préservation et de conservation, la formation des responsables et l'amélioration des conditions de conservation et de récolte des objets et de la documentation. La préservation et la protection des vestiges du patrimoine impliquent une large collaboration. Pour arriver à la préservation et à la protection des ressources du patrimoine tanzanien, el faut que la communauté scientifique et mondiale s'implique et soutienne ce projet à la fois techniquement et financièrement.
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78.
Nearly 200 new lead isotope analyses of sulphidic and oxidized ores from 26 copper mines on Cyprus show that the mines from different geological regions group in five distinctive isotopic groups, each with a substructure, related to the geological history of the ore formation. Comparison of lead isotope compositions of Bronze Age artefacts with these data can in many cases reveal the actual mines from which the copper for particular artefacts was obtained. The particular case of the provenance of the copper for 78 Late Bronze Age copper ‘oxhide ingots’found in Cyprus, Crete, Greece, Sardinia, Turkey and Bulgaria is discussed. The data show that all oxhide ingots so far analysed, dating to the fourteenth century BC and later, were made of copper consistent isotopically with only one mining region in the geographical north of Cyprus, and especially the Apliki mine. The study provides further evidence which supports the validity of the conventional approach to the use of lead isotope analysis for provenancing metals; this evidence is antithetical to recent suggestions of a model for the production of copper oxhide ingots which involved widespread mixing of copper from a number of ore sources throughout the Mediterranean.  相似文献   
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BOOK REVIEWS     
Book Reviews in This Article: Trois ?uvres Inédites de mystiques musulmans: āqq? al-Bal?, Ibn ?, Niffarā. By Paul Nwyia. The Formative Period of Islamic Thought. By W. Montgomery Watt. The Arab Mind. By Raphael Patai. l?m? al-Adab al-M?r f? Mir? (Bio-bibliographical Critical Series), No. 1, h?āūsayn. By Hamdi Sakkut and Marsden Jones. A History of the Crusades. Kenneth M. Setton, general editor. Volume III, The Fourteenth and Fifteenth Centuries , edited by Harry W. Hazard. The Muslim Dilemma in India. By M. R. A. Baig. Who is Maudoodi ? By Maryam Jameelah. A Tacit Alliance. By S. K. Crosbie.  相似文献   
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