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11.
Recent lidar and pedestrian surface surveys have remapped the well-known Mesoamerican site of Izapa and the surrounding Soconusco piedmont. These data document: 1) occupation from the surrounding piedmont environment, 2) significantly larger estimates of the site's size during both the Formative and Classic periods as well as 3) new architectural features from the monumental site core. Methodological issues are outlined for combining high precision lidar mapping with ground truthing and pedestrian survey that focuses on surface collection of temporally diagnostic artifacts. Results are presented for 670 mounds documented in an area of 43.1 sq km in and around the ancient capital of Izapa.  相似文献   
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Considering the likely unfavorable behavior under seismic action of adobe construction, this article aims at providing a seismic fragility characterization of two adobe Portuguese traditional buildings, using numerical models calibrated over experimental results. The study of such two case-study buildings in the region of Aveiro contributes to the understanding of the seismic fragility of adobe construction in the region in general. The buildings were numerically modeled to estimate their structural behavior under seismic loading using adobe material properties that were calibrated based on the experimental results of a cyclic in-plane test of a full-scale double-Tshaped adobe wall. The method chosen to characterize adobe masonry and model its nonlinear behavior followed a total strain crack-based macro-modeling (TSCM) approach, whereas pushover analysis was carried out to reproduce the pseudo-static experimental test in order to enable a refined calibration of adobe masonry mechanical properties. Fragility functions were then derived, based on the above-mentioned numerical models, using nonlinear static analysis, bringing further insight on the seismic fragility of traditional Portuguese adobe construction.  相似文献   
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The most common indicator used to measure spatial dependence is Moran's I proposed by statistician Patrick A. P. Moran in 1950. The index is simple to use and applies the principle of the Pearson correlation coefficient, although it incorporates a proximity measure between elements. However, Moran's I tends to underestimate real spatial autocorrelation when the number of locations are few. This study aims to present a modified version of Moran's I that can measure real spatial autocorrelation even with small samples and check for spatial dependence.  相似文献   
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Geographical and Temporal Weighted Regression (GTWR)   总被引:3,自引:0,他引:3       下载免费PDF全文
Both space and time are fundamental in human activities as well as in various physical processes. Spatiotemporal analysis and modeling has long been a major concern of geographical information science (GIScience), environmental science, hydrology, epidemiology, and other research areas. Although the importance of incorporating the temporal dimension into spatial analysis and modeling has been well recognized, challenges still exist given the complexity of spatiotemporal models. Of particular interest in this article is the spatiotemporal modeling of local nonstationary processes. Specifically, an extension of geographically weighted regression (GWR), geographical and temporal weighted regression (GTWR), is developed in order to account for local effects in both space and time. An efficient model calibration approach is proposed for this statistical technique. Using a 19‐year set of house price data in London from 1980 to 1998, empirical results from the application of GTWR to hedonic house price modeling demonstrate the effectiveness of the proposed method and its superiority to the traditional GWR approach, highlighting the importance of temporally explicit spatial modeling.  相似文献   
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Of 55 17th‐century wrecks located around the world identified as Iberian, 37 have either been destroyed, looted, or salvaged by treasure hunters, and just 11 the subject of archaeological work. Of these, only seven have been published: structural components, planking, fasteners, caulking, and other hull remains are reported to different degrees of detail. This article compares hull components within this small sample to assess the shared traits, or distinctive Iberian shipbuilding tradition, proposed by Oertling (2001; 2005), Castro (2008), and Hormaechea et al. (2018: 64–65). Additional traits are proposed that have been observed in the archaeological record.  相似文献   
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The East African coast is a rich domain for underwater cultural heritage, whose archaeological remains are only beginning to reveal the extent of indigenous nautical technology, regional and international social contacts, and far-reaching maritime trade routes sailed for millennia. The diversity of remains found under water range from cultures up and down the East African coastline to further afield: from China, points surrounding the Indian Ocean, to the Persian Gulf, Middle East and Europe. In Mozambique, important steps to investigate and preserve this heritage have been taken over the last 20?years by several groups of local scholars in collaboration with international research institutions. However, this heritage, especially that which lies along the northern Mozambique coast, has also been subjected to extensive and serious disturbance by commercially-oriented salvage programs. These salvage activities have not only had a very negative impact on the state of the cultural resources themselves, but have also prevented the access of legitimate scholars to these resources??particularly grave is the intervention at Mozambique Island, a UNESCO World Heritage Site. Among the meritorious efforts to mitigate this situation, in Mozambique and world-wide, the 2001 UNESCO Convention for the Protection of the Underwater Cultural Heritage is an outstanding initiative and needs to be ratified by Mozambique and other East African states.  相似文献   
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The concept of the extrapyramidal system comprises an amalgam of disparate and often conflicting ideas with a tortuous history. To the theoretical neuroscientist or practicing clinician, it promptly evokes semantic associations that are hardly reminiscent of its original meaning. The purpose of this article is to revisit the sources of the extrapyramidal concept and to examine the transformations that it went through from its inception, in the late 1890s, up to the neuroimaging revolution of the 1980s. Our review shows that the use of "extrapyramidal" as a surrogate for the basal ganglia, disorders of movement, or certain manifestations of spastic hemiplegia does not apply to humans; rather, it represents the historical product of the unwarranted translation of results of animal experimentation into the interpretation of clinical findings on human patients, misguided clinico-anatomic deductions, and fanciful phylogenetic notions. We conclude that the extrapyramidal concept is a valid and robust anatomic concept as long as it strictly refers to the collection of descending fibers originating in a few discrete brainstem tegmental motor nuclei that project to the spinal cord.  相似文献   
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