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271.
Locally made ceramics from Islamic sites in Ethiopia have been neglected in most archaeological studies, which tend to privilege imported Middle Eastern and Chinese/Southeast Asian ceramics. An assemblage of the local ceramics from the important trading site of Harlaa, in eastern Ethiopia (mid-sixth and fifteenth centuries AD), is the subject of this article. The study emphasizes the value of these ceramics as chronological markers, and for understanding regional and long-distance contacts, cultural innovations, processes of Islamization, and foodways.
相似文献272.
Timothy O'Riordan 《Scottish Geographical Journal》2013,129(2):151-165
Abstract Environmentalism is giving way to sustainability in a process that is aided by complementary shifts in economic, social and political arenas. Environmentalism was always a necessary first step. The shift towards sustainability is beginning to take place because the mood of the times is now ready to promote its early stages. However, as we contemplate more fully the fuller significance of sustainability, the very ethos of livelihood and lifestyle enters the frame of enquiry. Livelihood and lifestyle are part of the same set of phenomena defining personal and social identity, and economic well-being. But we can stillask two complementary questions. Are we seriously prepared to metamorphose into a sustainable life style? Can we devise ways to cope by drawing on multiple livelihoods? This will be one of the key issues for human geographers to examine in the coming decade. 相似文献
273.
Timothy P. Topper 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):427-443
A small assemblage of isolated Microdictyon plates is described from the lower Cambrian Ajax Limestone, Mt Scott Range (Flinders Ranges), South Australia. Microdictyon plates are primarily known from single, isolated, perforated phosphatic sclerites; only one species (M. sinicum) from the Chengjiang Lagerstätte is known from soft-bodied preservation of the complete organism. The isolated plates from South Australia display a wide range of morphologies potentially reflecting: 1, considerable diversification within the group at this time; 2, extensive intraspecific morphological variation; 3, different plate morphotypes along the trunk of the animal; or 4, significant ontogenetic variation in successive growth stages. The South Australian specimens are similar to several individual sclerites described from other Cambrian palaeocontinents, but appear closest to faunas described from South China. Problems associated with the taxonomy of isolated Microdictyon plates are discussed, including the lack of knowledge associated with intraspecific and/or ontogenetic variability and how individual plate morphology may relate to size or relative position along the length of the complete organism. 相似文献
274.
Paul Bodin John Vidale Timothy Walsh Recep Çakir Mehmet Çelebi 《Journal of Earthquake Engineering》2013,17(5):607-622
The Natural Resources Building (NRB) in Olympia, Washington, was shaken by three earthquakes (Mw = 5.8, 6.8, and 5.0) between 1999 and 2001. Building motions were recorded on digital accelerographs, providing important digital recordings of repeated strong shaking in a building. The NRB has 5-stories above grade with 3 sub-grade levels and a ductile steel-frame elongated in the E-W direction. The upper two floors extend significantly beyond the lower 3 on the southern and eastern sides. N-S motions dominate the fundamental modal vibrations of the building system. In the 1999 Satsop M5.8 earthquake, the frequency of this fundamental system mode was 1.3 Hz during motions of 10% g. The frequency dropped to 0.7 Hz during the 2001 M6.8 Nisqually strong motions. Moreover, the Nisqually recordings reveal both numerous high-frequency transients of up to 0.18 g, several of which are visible on widely spaced sensors, and long-term tilts of some of the sensors. The weaker 2001 M5.0 Satsop earthquake motions showed the frequency remained depressed at less than 1 Hz for the eastern side of the structure, although the western side had recovered to 1.3 Hz. An ambient noise survey in 2008 showed the fundamental frequency of N/S vibrations remains about 1.0 Hz for the eastern side of the building and 1.3 Hz for the western side. These results suggest that in the Nisqually earthquake, the east side of the NRB suffered a permanent reduction in fundamental mode frequency of 37% due to loss of system stiffness by undetermined mechanism. 相似文献
275.
Timothy Warner 《Geography Compass》2011,5(10):781-798
Texture has been of great interest to remote sensing analysts for more than three decades. This paper is a review of texture approaches that are based on a moving window, or kernel, and that generate a summary measure of local spatial variation, which is assigned to the central pixel of the kernel. Texture methods are challenging to implement, partly because of the many parameters that need to be set prior to running a texture analysis. The list of parameters includes the texture order, metric, kernel size, and spectral band. For second‐order metrics, additional parameters that need to be set include radiometric re‐quantization, displacement, and angle. Although few general rules of thumb can be provided in selecting texture analysis parameters, understanding the conceptual role of these parameters helps illuminate the options available. In addition, future opportunities in object‐oriented texture, adaptive texture measures, and multi‐scale texture fusion offer the potential for addressing some of the inherent challenges in the application of texture in image analysis. 相似文献
276.
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278.
This paper investigates the role of the business size distribution on income and employment growth in U.S. counties from 1990 to 2000. We measure the business size distribution as the share of employees across nine establishment size categories that range from microfirms (one to four employees) to large firms (1,000+ employees) and using three indices similar to a Gini coefficient. Results show that the business size distribution has a significant impact on county‐level growth patterns. Employment shares in small firms increase employment growth, but decrease income growth. One possible conclusion suggests policies emphasizing small firms and entrepreneurship during times of high unemployment. 相似文献
279.
Peterborough Ware is now recognized as the dominant ceramic tradition of the middle Neolithic in southern Britain during the period 3400–2800 BC, part of a wider north European family of Impressed Wares. Drawing on an extensive inventory of 600 recorded assemblages constructed by enriching previous lists with the results of development‐driven research carried out over the last 20 years or so, this paper reviews the production, distribution and use of Peterborough Ware. Support is found for the traditional sub‐division of the Peterborough Ware series into three sub‐styles: Ebbsfleet, Mortlake and Fengate Wares on the basis of the materials used, forms, and the decorative schemes preferred in each. The overall distribution of Peterborough Ware focuses on south‐eastern Britain although there are important assemblages from areas to the west and north, especially those composed of Mortlake Ware. The range of contexts in which Peterborough Ware was deposited is wide, but suggests a backward‐looking attitude in which the users of this style of pottery were trying to connect with their past. 相似文献
280.
Timothy Kircher 《European Legacy》2015,20(5):435-449
AbstractThe essay explores humanism’s modernity by inquiring into the way the fifteenth-century humanist cultural program posited moral values and, at the same time, contributed to a sense of moral confusion. While Niccolò Niccoli, Pier Paolo Vergerio, and Leonardo Bruni associated ethical enlightenment with learning and even social acclaim, Leon Battista Alberti criticized these assumptions not only for their susceptibility to political manipulation but also for their failure to cultivate the attributes they promised: virtue, and by extension happiness and tranquillity. The tensions in humanist culture between conformity and dissent, rational certainty and sense of mutability, generated the creative energy that we, as moderns, have come to attribute to this culture. 相似文献