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941.
Ripley's K‐function is a test to detect geographically distributed patterns occurring across spatial scales. Initially, it assumed infinitely continuous planar space, but in reality, any geographic distribution occurs in a bounded region. Hence, the edge problem must be solved in the application of Ripley's K‐function. Traditionally, three basic edge correction methods were designed for regular study plots because of simplified geometric computation: the Ripley circumference, buffer zone, and toroidal methods. For an irregular‐shaped study region, a geographic information system (GIS) is needed to support geometric calculation of complex shapes. The Ripley circumference method was originally implemented by Haase and has been modified into a Python program in a GIS environment via Monte Carlo simulation (hereafter, the Ripley–Haase and Ripley–GIS methods). The results show that in terms of the statistical powers of clustering detection for irregular boundaries, the Ripley–GIS method is the most stable, followed by the buffer zone, toroidal, and Ripley–Haase methods. After edge effects of irregular boundaries have been eliminated, Ripley's K‐function is used to estimate the degree of spatial clustering of cities in a given territory, and in this paper, we demonstrate that by reference to the relationship between urban spatial structure and economic growth in China.  相似文献   
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Archaeological survey by the Qatar National Historic Environment Record Project (QNHER) in 2009, led to the discovery of a Neolithic flint scatter, a settlement and an ancient, raised shoreline associated with higher, mid‐Holocene sea levels at Wādī ?ebay?ān, north‐western Qatar (Al‐Naimi et al. 2010, 2011; Cuttler, Tetlow & Al‐Naimi 2011). The QNHER project is a collaboration between Qatar Museums and the University of Birmingham, which over the past five years has developed a national geospatial database for the recording of archaeological sites and historic monuments in Qatar. A significant aspect of the project involved archaeological survey and excavation in advance of major construction projects. Between 2012 and 2014 excavations at Wādī ?ebay?ān revealed a burial of a typology previously unknown in Qatar, the unmarked graves (Cuttler, Al‐Naimi & Tetlow 2013).  相似文献   
944.
Human skeletons were recovered in two unmarked burials blown to the surface of a dune south‐west of Jebel al‐Emeilah in the Central Region of the Sharjah Emirate (UAE). Sasanian stamp seals were found associated with one of the individuals. A bone fragment of this individual provided a direct radiocarbon date placing it in the Middle Sasanian period. With the aid of strontium isotope analysis it was possible to determine that the two individuals were immigrants to the area that is now part of the UAE.  相似文献   
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This paper presents the debate over the presence or absence of keels in the construction of Egyptian ships of the dynastic period. It contains an analysis of ship representations and models dating to the 18th–20th dynasties of the New Kingdom (c.1539–1077 BC) that provide evidence for the introduction of keels in Egyptian shipbuilding, and new archaeological material from excavations at Thonis‐Heracleion that sheds more light on the question.  相似文献   
947.
Nationalism and revolution have generally been held to go together. Many nation‐states have had their origins in revolution, from the Americans in the 18th century to a host of Third World nation‐states in the 20th century. Generally, both modern revolutions and modern nationalism have the same origins, in 18th century Enlightenment thought. But this paper argues that, despite this common origin, the principles of revolution and nationalism are divergent, and can set one against the other. Revolutions emphasise freedom and equality; nationalism emphasises integration and unification. These principles can clash, though not inevitably and not always. The paper examines the 1789 French Revolution, the 1848 revolutions and the 1917 Russian revolution. It shows that in the first two cases, revolutionary aspirations came up against and were eventually displaced by nationalist aims. In the case of 1917, revolution paradoxically, and unintentionally, institutionalised nationalism. These examples show that, though linked at some high level of modern thought, revolution and nationalism express different and at times divergent strands of modernity.  相似文献   
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