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61.
Archaeological practice within the European context of heritage management is facing huge challenges in ways of recording and reproduction of ex-situ preserved sites. As a consequence of the Valletta-treaty, numbers of archived images and drawings of excavated structures as prime sources of past human activity, are exponentially growing. Contrarily to portable remains however, their future study and revision is biased by the two-dimensional character of the recorded data, rendering difficult their future reconstruction for new study or public dissemination. A more realistic three-dimensional (3D) way of recording and archiving should be pursued. In this paper the possibilities for 3D registration of archaeological features are examined in a computer vision-based approach using the PhotoScan software package (Agisoft LCC). It proved to be a scientific and cost-effective improvement compared to traditional documentation methods. Advantages can be found in the high accuracy and straightforwardness of the methodology. The extraction of an orthophoto or a Digital Terrain Model from the 3D model makes it feasible to integrate detailed and accurate information into the digital archaeological excavation plan. The visual character of 3D surface modeling offers enhanced output-possibilities allowing a better documentation of in-situ structures for future research and a higher public participation and awareness for the archaeological heritage.  相似文献   
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那是春暮夏初的时节,陡峭的丘壑幽谷中,一种名叫铁木的寻常树木正绽放着一簇簇亮丽的黄花。山谷迤逦向北,延伸到今日被称为意大利阿尔卑斯山的莽莽群山中。一个男人行色匆匆地穿过一片他所熟悉的森林,右手的伤口痛得他龇牙咧嘴,时不时地,他还会停下来侧耳倾听,看身后是否有人在尾随。他逃上山坡,停下来歇脚,这时候,铁木的黄色花粉宛如看不见的雨幕,丝丝洒落到这个人的食物和饮水中。五千年后,这些古老花粉的痕迹依然保存在这位被我们叫做“冰人”的新石器时期猎人体内,成为那一年、那一刻的精微记录:他就在那时穿过森林进入附近的深山,在那里遭遇他最终的宿命。[编者按]  相似文献   
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In this article it is argued that conventional agro-ecological and organizational concepts used in pastoral development are strongly biased towards the formulation and enforcement of norms. This leads development experts to attempts to control pastoralists and their herds. The policies and development interventions based on these assumptions have been largely unsuccessful. As a consequence attention for dryland areas and pastoral development has declined among researchers and development agencies. An important reason for this failure is the fundamental misfit between these normative concepts and the reality of dryland ecosystems and pastoral society. In order to show this, an alternative view on rangeland ecology and pastoral society is presented, supported by a case study of Fulbe pastoral society in dryland Central Mali. The authors argue that approaches to pastoral development must be revised in the direction of the dynamics inherent in the pastoral way of life.  相似文献   
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A data-determined method is proposed to test for the law of one price as a long-run equilibrium condition and to identify which markets in a network of spatially dispersed commodity markets quote the reference price. The method consists of supplementing Johansen's FIML cointegration procedure with a permanent-transitory decomposition and rules of inference in linear time-series models with unit roots. As an example, we apply our method to prices of six corn markets in Benin. We find that the law of one price holds in the long-run. It appears that two rural markets quote the reference price: their prices adjust fastest towards the permanent change induced by the common stochastic trend.  相似文献   
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Although the aetiology of bone pathologies in cattle is poorly documented, various deformations in the skeleton have been attributed to draught exploitation in the archaeozoological literature. This paper summarizes the results of an osteological study that was undertaken on the feet of modern draught oxen. This led to the definition of a series of draught‐related anomalies. In an attempt to describe the pathologies in a more consistent and quantitative way, a scoring scale for each individual bone pathology was established. The developed method is applied to cattle remains from four Roman and one late medieval site. The distribution of the observed pathological indices (PIs) on the first phalanges is interpreted in terms of the age structure of the cattle populations, and the possible modes of cattle exploitation and meat consumption in various settlement types. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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Previous geographical research with street children has principally focused on their micro-geographies in the city. This paper draws on nomadic and episodic processes of homeless mobility, to explore street children's geographies from a wider social, spatial and temporal perspective. By examining street life in Kampala, Uganda as a continued negotiation of public/private and street/non-street locations, the fluid nature of street children's identity is illustrated. Over time, movement between spaces, such as divergent city niches, institutions, homes and other towns, is often subject to power relations operating in street/non-street spaces with each requiring conformity to a different set of values and behaviours. The paper demonstrates how this results in children's street identity changing as they move through the street life path.  相似文献   
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