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141.
Alan T. Murray 《Geographical analysis》2018,50(3):207-222
Among the wide range of geographic analysis methods are service coverage models. These location analytic approaches have been invaluable for better understanding existing (and past) conditions, deriving creative plans, and developing policy for addressing associated societal problems. Increasingly sophisticated spatial information and better knowledge about interrelated mechanisms of process and behavior have made it possible to enhance coverage models, enabling more nuanced formalizations to be devised. This has proven both important and essential in many ways. Mathematical details associated with service coverage models are derived to highlight evolving capabilities. Empirical results are presented in order to illustrate the significance and substantive importance of advanced location analytics capabilities. 相似文献
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Jennifer M. Miller Elizabeth A. Sawchuk Amy L. R. Reedman Pamela R. Willoughby 《African Archaeological Review》2018,35(3):347-378
Shell beads are well established in the archaeological record of sub-Saharan Africa and appear as early as 75,000 BP; however, most research has focused on ostrich eggshell (OES) and various marine mollusc species. Beads made from various land snails shells (LSS), frequently described as Achatina, also appear to be widespread. Yet tracking their appearance and distribution is difficult because LSS beads are often intentionally or unintentionally lumped with OES beads, there are no directly dated examples, and bead reporting in general is highly variable in the archaeological literature. Nevertheless, Achatina and other potential cases of LSS beads are present at over 80 archaeological sites in at least eight countries, spanning the early Holocene to recent past. Here, we collate published cases and report on several more. We also present a new case from Magubike Rockshelter in southern Tanzania with the first directly dated LSS beads, which we use to illustrate methods for identifying LSS as a raw material. Despite the long history of OES bead production on the continent and the abundance of land snails available throughout the Pleistocene, LSS beads appear only in the late Holocene and are almost exclusively found in Iron Age contexts. We consider possible explanations for the late adoption of land snails as a raw material for beadmaking within the larger context of environmental, economic, and social processes in Holocene Africa. By highlighting the existence of these artifacts, we hope to facilitate more in-depth research on the timing, production, and distribution of LSS beads in African prehistory. 相似文献
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M. Bhandari S. D. Bharti M. K. Shrimali T. K. Datta 《Journal of Earthquake Engineering》2018,22(6):989-1007
The behavior of base-isolated building frame is investigated with the help of a numerical study for far-field and near-field earthquakes with directivity and fling-step effects. Both design-level and extreme-level earthquakes are considered. Selected response parameters are peak floor displacement, acceleration, base shear, and isolator displacement. Inelastic behavior of base-isolated structure during the earthquake is investigated performing nonlinear time history analysis of a ten-story building frame. This study shows that base isolation is not effective for near-field earthquakes. Even for design-level earthquake, the frame gets significantly into inelastic range for earthquakes with fling-step effect. 相似文献
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Solution strategies are presented to address three potential problems in the empirical derivation of fragility functions from empirical data using the maximum likelihood method. The first strategy addresses the case of fragility curves that cross, the second strategy incorporates demand uncertainty in fragility derivation from post-earthquake reconnaissance data, and the third strategy provides a framework for the resolution of conflict between empirical data and expert opinions. The advantages and disadvantages of the proposed solution strategies are discussed and their use is demonstrated by way of suitable illustrative examples. 相似文献
148.
Csaba Albert Tóth Attila Rákóczi Sándor Tóth 《Conservation and Management of Archaeological Sites》2018,20(3):113-142
According to the Act of 1996 on nature protection, mounds (kurgans) are natural monuments protected nationally in Hungary. According to the law, all kurgans in Hungary were to be surveyed by 2002, and 1692 were included in the cadastre. Fewer than half of the kurgans remained intact due to numerous anthropogenic impacts. A high number of disturbing artificial buildings together with soil erosion, soil removal, and afforestation have significantly reduced the landscape value of kurgans. In 2002, 51.5% of the surveyed kurgans still represented some kind of a value and thus their protection became one of the most urgent tasks of nature conservation and archaeology. According to a Hungarian ministerial decree, established on the basis of an EU Council decree, the area of kurgans under cultivation must be removed from cultivation. By 2015, in the area of 90% of the kurgans under cultivation this land use, which caused significant erosion, was terminated. 相似文献
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Elizabeth Kaufer Busch 《Perspectives on Political Science》2018,47(2):104-114
Sexual assault is a heinous crime that for decades had failed to receive needed attention on college campuses across the country.1 That changed on April 4, 2011, when the Department of Education's (ED) Office of Civil Rights (OCR) issued a “Dear Colleague” letter (DCL) on sexual harassment and violence, which purported to clarify “Title IX's requirements related to student-on-student sexual harassment, including sexual violence, and explains schools' responsibility to take immediate and effective steps to end sexual harassment and sexual violence.”2 The intent of the letter to mete out swift justice for sexual assault survivors and to punish perpetrators and negligent institutions became immediately clear as the number of schools under OCR investigation began to swell. In response, colleges and universities have instilled a vast machinery of administrative procedures to adhere to the new requirements. At last count the OCR was conducting more than 300 investigations of nearly 200 colleges and school districts for the handling of sexual harassment and assault under Title IX.3 相似文献
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