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1.
Many factors governed the penetration efficacy of prehistoric projectile weaponry. Archaeologists broadly focus their efforts on understanding the effect of stone weapon tips because these specimens are often the only part of the weapon system that survives in the archaeological record. The tip cross-sectional area (TCSA) and perimeter (TCSP) of stone weapon tips have been shown to correlate with target penetration depth. Here, using results from both static and dynamic penetration testing, we compare TCSA and TCSP against other tip geometry metrics: lateral surface area (LSA) and volume (V). Our analyses broadly show that using a single-point geometry metric evaluated at multiple locations along the length of the point, or using multiple geometry metrics evaluated at a single location, better predicts required energy than using a single-point geometry metric evaluated at a single location. Our results also show that in the case where a single geometry metric evaluated at multiple locations is used LSA provided the most robust prediction models. Finally, our results show that for the case where all geometry metrics evaluated at a single location are used the location that provides the most robust prediction model is dependent on how far the point penetrated the target.  相似文献   
2.
Northeastern China is one of the centers of early development of agriculture and sedentary life, as well as of the subsequent development of social complexity and distinct cultural attributes. While the outlines of this trajectory are clear, its important details are still elusive. Like all other regions of northern China, there is little data on the all-important transition from nomad hunter-gatherers to sedentary agriculturalists. The Fuxin Regional Survey was designed as the first step in accumulating new data and addressing the geographic and ecological contexts of these socioeconomic processes. Among the most remarkable results of this survey is the identification of early ceramics, which possibly predate the transition to agriculture. The systematic collection and analysis of stone tools was done in a way never before done in this region. Analysis of our findings, using GIS and other methods, sheds new light on the local trajectory of human adaptation in this area.  相似文献   
3.
Students training to become primary school teachers appear to have little awareness of the core concepts of geography (teaching). To ensure that future primary school teachers are able to develop their pupils’ geographical awareness, a six weeks programme was developed. The characteristics of this programme – named Consciously Teaching Geography (CTG) – are: principles of good geography teaching, conjunction and a recurrent structure during training, modelling and reflection. In a quasi-experimental research design the question is answered what the effects are of CTG on the development of pedagogical content knowledge (PCK) for the subject of geography of first year primary student teachers. The results indicated that the programme has a positive effect on the domain-specific PCK development in the short term.  相似文献   
4.
Francesca Fois 《对极》2019,51(1):107-128
This paper analyses the experimental nature of alternative spaces and the affective, emotional and embodied experience their enactment generates. In so doing, it grounds the analysis on the intentional community of Damanhur (Italy), as an example of experimental spaces. Scholarship concerning intentional communities draws on utopian studies that consider them as utopian laboratories. More recently, non‐representational approaches have emphasised the processual nature of utopias, yet studies have overlooked the experimental nature of these alternative spaces. Drawing upon in‐depth ethnographic data, this paper engages with community experimentations that took place in Damanhur for residents and visitors. It illustrates how utopian enactment is experimental and thus, disordering, unsettling and creative. Moreover, I argue that experimentations are not limited to unsettling the social structure of the community and, when studying the enactment of alternative spaces, emphasis should also be on their capacity to affect the individual.  相似文献   
5.
Our blind tests are distinctive for they were conducted on replicated stone tools used for a variety of tasks that included the processing of animal remains and plants. The analyst was required to differentiate an array of residues from microscopic morphological characteristics, using light microscopy. The original aim of our first tests was to assess the analyst's ability to identify a variety of plant and animal residues, but issues and problems that arose during the testing process made it clear that greater value might be gained from the lessons that we learnt about methodology and the direction for future micro-residue research. We show that problems identified during our first tests stimulated research. Amongst other things, we learnt to distinguish plant and animal remains more confidently than previously. Our residue analyses are firmly embedded in wider archaeological research and our tests help to explain why there are sometimes contradictions between the evidence from archaeologically recovered remains and residues on stone tools. A further outcome of the tests is that we have adopted a multi-stranded approach that provides a cautious, but secure strategy for identifying and interpreting use-residues. Our studies of contaminants through replications have also been invaluable for distinguishing incidental residues from use-related residues.  相似文献   
6.
建国初期,为了迅速恢复和发展农业生产,在中央政府的领导下,我国农村开展了全面的农具改良工作.政府通过建立农具管理和服务机构,兴办工厂,开展宣传教育、发动群众,大量增补旧农具,积极推广使用新式农具.农具改良在一定程度上提高了农业生产技术,改进了生产效率,增加了农业产量,同时奠定了农机产业的基础,为后期的农业机械化进程做了铺垫.由于对农村的具体情况和农具的实际需求了解不充分,农具设计和制造水平低,新式农具质量较低,价格偏高,技术传授和维修服务差,经营管理相对落后,新式农具推广使用未能达到预期的目标,发挥应有的作用.农具工作政策和措施的失误,不仅造成了人力和物力资源的浪费,也损害了政府在群众中的形象.  相似文献   
7.
This paper is the outcome of a lecture held at the Institute of Archaeology, University College London. It provides a summary in English of the archaeozoological research work which has been carried out in Central Europe during the last 30 years, with special reference to material from medieval times. It is shown that a thorough zoological analysis of bones from excavations provides much information for historical interpretation. Not only was the ratio of wild and domestic animals or of the different species of interest, but also the age and sex structure of the population by taking the function of the site into consideration. Some observations on animal teeth gave indications of distinctive handicrafts. Cut marks on cervical vertebrae of horse skeletons found as grave goods from early medieval times were considered in connection with beliefs and juridical conceptions of that time.  相似文献   
8.
Kristin Reynolds 《对极》2015,47(1):240-259
Many studies have documented the benefits of urban agriculture, including increased food access, job creation, educational opportunities, and green space. A focus on its social benefits has fed an association of urban agriculture with social justice, yet there is a distinction between alleviating symptoms of injustice (such as disparate access to food or environmental amenities) and disrupting structures that underlie them. Despite its positive impacts, urban agriculture systems may reinforce inequities that practitioners and supporters aim to address. This paper reports findings from a 2‐year study of urban agriculture in New York City, which found race‐ and class‐based disparities among practitioners citywide. Using the lens of critical race theory, it argues that a failure to examine urban agriculture's role in either supporting or dismantling unjust structures may perpetuate an inequitable system. The paper concludes with recommendations for urban agriculture supporters and scholars to help advance social justice at structural levels.  相似文献   
9.
We ask to what degree consumers who act out movement practices (eg local food consumption) may do so without regard for larger environmental and social justice implications, and how focus on individual concerns reflects the partial (but increasing) neoliberalization and depoliticization of the alternative food movement. Coupling narratives from five citizen‐consumers with analysis of organizational discourse from a major food movement organization in Massachusetts’ Pioneer Valley, we examine the interplay of individual and collective identity to point to places where modified discourse and movement tactics may produce more fruitful outcomes (eg greater community food security). Ultimately, we argue that individualistic interpretations of alternative food are reinforced by organizational campaigns that shape collective identity, casting “buying local” as a heroic act, thereby re‐casting others as anti‐heroes. Counteracting individualization with a new politics of possibility should be prioritized, as citizen‐consumers will inevitably determine future landscapes of food, environmental sustainability and social justice.  相似文献   
10.
This article argues that contemporary independent documentary filmmaking in China has been used as a tool by Chinese citizens to intervene in the public sphere and to provoke social change. I therefore propose to look at the phenomenon of Chinese video activism under the umbrella of alternative media. In particular, I take into consideration the “rhizomatic” media approach, which focuses on the interaction of alternative media with authority, the market and civil society. The case studies I present consist of several documentary projects completed between 2004 and 2010 that opened up spaces of dialogue between filmmakers and local authority, mass media and civil society. The paper claims that documentary films have an impact on audiences, whose members are consequently motivated to engage in discussion and action. I argue that activist video-making in China is reshaping the identity of urban citizens: through filmmaking, urban citizens claim their right to access information and demonstrate their will to participate and intervene in social issues.  相似文献   
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