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31.
Architectural reconstructions of plankhouses are central to the study of household and community organization on the Northwest Coast of North America. However, the sample of substantially excavated houses is constrained by their size, stratigraphic complexity, and typically limited surface expression. We present the results of a magnetic gradiometry survey of the Dionisio Point site (DgRv-003) village, occupied ca. a.d. 500–700 on the coast of British Columbia, Canada. Survey of four house platforms reveals patterning of magnetic anomalies consistent with the structure of shed-roof houses, a design recorded ethnographically and identified archaeologically at the site. These results suggest a consistent pattern of spatial and, potentially, social organization of the households. The similarity of patterns suggests that magnetometry may be useful for guiding plankhouse excavations elsewhere on the Northwest Coast, providing a means for expanding our knowledge of houses without relying solely on traditional excavation methods.  相似文献   
32.
Model assessment is one of the most important aspects of statistical analysis. In geographical analysis, models represent spatial processes, where variability in mapped output results from uncertainty in parameter estimates. Slight spatial misalignments can cause inflated error scores when comparing maps of observed and predicted variables using traditional error metrics at the level of individual spatial units. We conceptualize spatial model assessment as a continuous value map comparison problem and employ methods from image analysis to score model outputs. The structural similarity index, a measure that attempts to replicate the human visual system using a local region approach, is used as an exploratory map comparison statistic. The measure is implemented within a Bayesian spatial modeling framework as a discrepancy measure in a posterior predictive check of model fit. Results are reported for simulation studies representing a variety of spatial processes in a spatial and space–time context. A case study of rainfall mapping in Sri Lanka demonstrates the proposed methodology applied to assessment of Bayesian kriging interpolations. Both simulation studies as well as the case study demonstrate that the approach reveals hidden spatial structure not uncovered by traditional methods. The spatially sensitive assessment methodology provides a diagnostic tool to support spatial modeling and analysis. La evaluación de modelos es uno de los aspectos más importantes de análisis estadístico. En el análisis geográfico, los modelos representan procesos espaciales en los que la variabilidad en los outputs es el resultado de la incertidumbre en los parámetros estimados. Leves desajustes espaciales pueden inflar los valores de error en la comparación entre los mapas de las observaciones y los mapas de las predicciones de las variables si es que se usan medidas tradicionales de medición de error al nivel de unidades espaciales individuales. Los autores conceptualizan la evaluación de modelos espaciales como un problema de comparación mapas de valor continuo y emplea métodos de análisis de imágenes para cuantificar los resultados del modelo. Se utiliza el índice de similitud estructural (SSIM), una medida que intenta replicar el sistema visual humano utilizando un enfoque de región local, como técnica de exploratoria comparación estadística de mapas. El índice es implementado dentro de un marco de modelización espacial bayesiano como medida de discrepancia en la comprobación posterior de predicción del desempeño del modelo. Los resultados se presentan para varios casos de simulación que representan una serie de procesos espaciales en un contexto espacio‐temporal y espacial. Un estudio de caso de mapeo de lluvias en Sri Lanka sirve como demostración de la metodología propuesta y su aplicación a la evaluación de las interpolaciones tipo krigeage (kriging) bayesianas. Tanto los estudios de simulación, así como el estudio de caso demuestran que el enfoque propuesto revela la estructura espacial oculta no evidenciada por métodos tradicionales. La metodología de evaluación espacialmente sensible que se presenta en este artículo proporciona una herramienta de diagnóstico para apoyar la elaboración de modelos y análisis espacial. 模型评估是统计分析中最为重要的内容之一。在地理分析中用模型表达空间过程,参数估计的不确定性会导致地图输出结果的可变性。当采用传统误差指标度量,在个体空间单位水平上进行观测和预测变量的地图比较时,微小的空间错位就可能导致误差的倍增。为此,本文通过将空间模型评估指标概念化为一个连续值图比较问题,并利用图像分析方法来评定模型输出。一种尝试以局域方法仿制人类视觉系统的度量指标——结构相似指数(SSIM),被用作为探索性地图的比较统计量。在贝叶斯空间模型框架下实现其量算,并将其作为一个偏差度量应用于模型拟合的后预测校验。仿真研究的结果显示出空间及时空环境下多类空间过程。以斯里兰卡降雨过程图为案例,展示了上述方法对贝叶斯克里格插值的准确性评估。仿真研究与实证结果均证明本文提出的方法可揭示以往传统方法掩盖的空间结构特征,空间敏感性评价为本研究的空间建模和分析提供了一个诊断工具。  相似文献   
33.
In this article, I examine black queer nightlife in Soweto and its relationship with the making of black queer space in South Africa. Through an in-depth examination of the microgeographies of a Soweto stokvel party, I reveal the complexities of post-apartheid formations of race, class, gender, and sexuality. Employing the idea of usable space, I highlight quotidian practices of leisure as an important site for understanding cultural creativity within the marginalized spaces occupied by black South African queers. Performance and performativity are central to organizing nightlife spaces and reveal both the possibilities and limits encountered by black queers as they try to construct livable lives.  相似文献   
34.
A small iron gun recovered from the wreck of the Caroline warship Swan has been identified as a drake, a lightweight tapered-chamber design dating from the 1620s. It is the only known cast-iron example of such a piece made by John Browne, gunfounder to Charles I, who was the leading figure in its development and manufacture in England. The gun was found together with an associated carriage, port-lid, and case shot appropriate to its calibre.
© 2004 The Nautical Archaeology Society  相似文献   
35.
Colin McFarlane 《对极》2004,36(5):890-916
This paper is concerned with the various ways in which geographical imaginations are inflected in politics. It draws on examples from a three‐way partnership of civil society organisations based in Mumbai, India. This movement seeks to reconfigure the governance of anti‐poverty strategies by placing "poor people" at the centre of its activities. The partnership, which refers to itself as the Alliance , is involved in the mobilisation and creation of a range of alternative geographical imaginations that are inflected in the production of new spaces of political engagement. By exploring two of the Alliance's strategies—enumerations and exhibitions—I will illustrate some of the ways in which these alternative geographical imaginations feature in the creation of spaces of political engagement. These strategies involve the practical demonstration of the capacities of the poor to donors and states, and reflect a particular conception of the poor and social change.
The spaces of political engagement formed in part through the Alliance's work depend significantly on a commitment to non‐party alignment, an approach that has received criticism from NGOs and commentators involved with urban poverty. I will argue that the Alliance represents a broad development alternative—rather than a form of alternative development—which nonetheless is making substantial progress in the politics of citizenship in Mumbai.  相似文献   
36.
37.
In the eleventh and twelfth centuries the salmon was abundant in the rivers of Normandy and there are numerous documentary references to rents from the salmon fisheries. But in the thirteenth and fourteenth centuries the salmon became a delicacy much in demand, and the multiplication of watermills increased the number of fisheries to such an extent that over-exploitation occured. Because of this, as well as for other reasons, salmon stocks in the fifteenth century were seriously depleted and the species became virtually extinct in much of Normandy.  相似文献   
38.
39.
The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
40.
This paper provides a critical analysis of the cultural and arts policies released by the Keating Labor government of the early 1990s and the current Howard Coalition government. While official definitions of Australian national identity promoted multiculturalism, analysis of Creative Nation, Labor's 1994 cultural policy, and recent statements from the Coalition, exposes the partiality of recent constructions. Both Labor and the Coalition's constructions of identity were based on an economism that was linked to traditional, masculine myths of egalitarianism and ‘mateship’. Such constructions show that neither party has embraced multiculturalism to the degree suggested by policy rhetoric.  相似文献   
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