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11.
Michael Pease Blanca Pérez-Lapeña Christopher Lant 《Journal of Geography in Higher Education》2019,43(1):40-55
This paper describes environmental systems games developed for energy and water resource use designed to be adaptable from high school to undergraduate use. Two of the games are computer simulations with adjustable levels of difficulty that can be done in a computer lab or as a homework assignment. The third is a peer-to-peer roleplayer game designed for an immersive in-class simulation. For the energy and the peer-to-peer water games, we describe (1) the overall strategy or story line adopted, (2) the manner in which the game is played by students in a classroom setting, (3) the use of scientific literature in conceptualizing and parameterizing the game, and (4) possible game extensions. Preliminary data from use at the undergraduate level shows that the games are very well-received by students and, consistent with other research on quasi-experimental simulations, likely enhance learning outcomes. 相似文献
12.
A New Methodology and Classification System for Describing Three‐Dimensional Particle Formats: Application to Clastic Lithic Products of Archaeological and Geological Origin
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A. Tarriño 《Archaeometry》2015,57(5):928-948
A new classification system is proposed to describe the volumetric formats of clastic lithic products of geological and archaeological origin. In order to build this operative classification, the rectangular block or cuboid is established as the standard geometric format to represent their three‐dimensional format (the X‐axis being length or long diameter, the Y‐axis being the width or intermediate diameter, and the Z‐axis being the thickness or short diameter) on a two‐dimensional diagram. To obtain this graph, each absolute coordinate (X, Y, Z) defining the prisms is projected on to an auxiliary plane with a new set of relative coordinates (x, y, z), expressed as the percentage of their sum. The projection generates a triangular diagram on which the indices of elongation and flatness are represented. A geometric transformation converting the triangular diagram into a quadrangular diagram has been produced in order to better represent the scatter points. Then, a double scale is necessary: (i) an absolute scale to quantify the indices, and (ii) a relative scale to calculate where the graphic locus is projected. This new graph also allows us to work with statistical parameters. Finally, two classic examples of applications selected from the literature are shown. 相似文献
13.
THE EFFECT OF ACCESSIBILITY ON PRODUCTIVITY IN SPANISH MANUFACTURING FIRMS 总被引:1,自引:0,他引:1
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David Martín‐Barroso Juan A. Núñez‐Serrano Francisco J. Velázquez 《Journal of regional science》2015,55(5):708-735
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers. 相似文献
14.
G. A. De La Fuente V. G. Josa G. Castellano S. Limandri S. D. Vera J. F. Días S. Suárez G. Bernardi S. Bertolino 《Archaeometry》2020,62(2):247-266
Particle-induced X-ray emission (PIXE), X-ray diffraction (XRD), electron microprobe analysis (EDS) and scanning electron microscopy (SEM) analytical techniques were used to characterize surface paints in pre- and post-fired Aguada Portezuelo decorated pottery. Surface paintings in black, white, red, brown, burgundy and ochre were analysed. Major, minor and trace elements were detected by PIXE, whereas XRD and SEM-EDS gave information on the main mineral phases and the characteristic morphology for each analysed pigment. The results obtained indicate that the main colour groups can be easily discriminated by PIXE, and they are characterized by only one pigment for each colour: hematite (red) and manganese mineral oxides (black), respectively, whereas white pigments are characterized by calcite, ghelenite and gypsum. 相似文献
15.
Aitziber Elola Jesus M. Valdaliso Susana Franco Santiago M. López 《European Planning Studies》2017,25(3):539-556
ABSTRACTThis paper contributes to the study of the role of public policies in the origins and evolution of clusters. Building on the existing literature, we set up a taxonomy of nine public policies that may have an impact on the emergence and evolution of clusters. Based on in-depth case studies of six clusters of the Basque Country, particularly representative of the industrial history of the region, we analyse the relevance of the different types of policies both in the emergence and evolution of clusters over time. In agreement with cluster literature, the paper concludes that public policies seem to have played only an indirect role across clusters and over their life cycles. Moreover, it points to the necessity of taking history and context into account, as most of the important policy measures highlighted by cluster literature today do not fit well with the previous policy and economic context. Finally, it also concludes that for cluster policies to be effective, the stages of the life cycle should be taken into consideration. 相似文献
16.
Jorge Machado Francisco J. Molina Cristo M. Hernández Antonio Tarriño Bertila Galván 《Archaeological and Anthropological Sciences》2017,9(8):1715-1743
The superposition of anthropogenic remains usually results in archaeological palimpsests, hindering an accurate characterization of the behavior underlying such remains. Aimed at facing this methodological constraint in the study of Palaeolithic contexts, we present a contextual approach to Neanderthal settlement dynamics based on an understanding of lithic assemblage formation processes. We focused on a set of lithic artifacts from the Middle Palaeolithic site of El Salt. With the goal of isolating temporally constrained units of behavioral analysis, we analyzed the spatial distribution of lithic, faunal and combustion remains. Then, the lithic records from each of the resulting units were analyzed from a genetic and technical perspective. This goal was achieved by identifying lithic Raw Material Units (RMU) through observations on reduction processes, refits and their spatial distribution. Our results suggest that El Salt SU X lithic remains represent several diachronic human occupation episodes and different site functions. This study illustrates the benefit of investigating lithic assemblage formation processes to alleviate the palimpsest problem in Palaeolithic contexts. 相似文献
17.
We present experimental data examining the energetics and identification of axial bipolar reduction in contexts of lithic miniaturization on milky quartz. These experiments answer two specific questions. First, does bipolar reduction provide any benefits over freehand reduction? Second, can axial bipolar reduction be distinguished from freehand reduction? Our data show that bipolar reduction requires significantly less time to reduce a percentage unit of core mass and to produce a millimeter of cutting edge on milky quartz than freehand reduction. Milky quartz bipolar reduction surpasses even the cutting edge production efficiency of obsidian pressure blades. We outline a series of quantitative criteria for identifying bipolar cores and flakes. Our results show that bipolar cores and flakes can be distinguished from those produced using freehand reduction by quantifying platform crushing, distal flake rebound scars, bulb shearing, as well as axial, bipolar, and splintered flake terminations. Our results challenge the widely held perceptions about the wastefulness of bipolar reduction and provide clear guidelines for identifying this reduction strategy in archaeological milky quartz assemblages. 相似文献
18.
A polyphasic tectonic‐fluid system of a fault that involves crystalline and carbonate rocks (Hospital fault, Barcelona Plain) has been inferred from regional to thin section scale observations combined with geochemical analyses. Cathodoluminescence, microprobe analyses and stable isotopy in fracture‐related cements record the circulation of successive alternations of hydrothermal and low‐temperature meteoric fluids linked with three main regional tectonic events. The first event corresponds to the Mesozoic extension, which had two rifting stages, and it is characterized by the independent tectonic activity of two fault segments, namely southern and northern Hospital fault segments. During the Late Permian‐Middle Jurassic rifting, these segments controlled the thickness and distribution of the Triassic sediments. Also, dolomitization was produced in an early stage by Triassic seawater at shallow conditions. During increasing burial, formation of fractures and their dolomite‐related cements took place. Fault activity during the Middle Jurassic–Late Cretaceous rifting was localized in the southern segment, and it was characterized by hydrothermal brines, with temperatures over 180°C, which ascended through this fault segment precipitating quartz, chlorite, and calcite. The second event corresponds to the Paleogene compression (Chattian), which produced exhumation, folding and erosion, favouring the percolation of low‐temperature meteoric fluids which produced the calcitization of the dolostones and of the dolomite cements. The third event is linked with the Neogene extension, where three stages have been identified. During the syn‐rift stage, the southern segment of the Hospital fault grew by tip propagation. In the relay zone, hydrothermal brines with temperature around 140°C upflowed. During the late postrift, the Hospital fault acted as a unique segment and deformation occurred at shallow conditions and under a low‐temperature meteoric regime. Finally, and possibly during the Messinian compression, NW‐SE strike‐slip faults offset the Hospital fault to its current configuration. 相似文献
19.
Cajal SR 《Journal of the history of the neurosciences》2006,15(4):326-340
This paper follows the form of that by Mazzarello that precedes it (Mazzarello, 2006) and presents an imaginary interview with Santiago Ramón y Cajal in December 1906. A few days earlier Cajal had been awarded the Nobel Prize for Physiology or Medicine, an award that he shared equally with Professor Camillo Golgi. Golgi had been recognized for his work as a pioneer into investigations of the nervous system, primarily on account of his discovery of the "black reaction" of silver chromate impregnation of whole nerve cells and their processes. Cajal had been recognized for his implementation of that method and for laying with it the foundations of what was to become modern neuroanatomical science. Paradoxically, the two awardees had been led by their researches to diametrically opposed views of the organization of the nervous system. Golgi believed in a continuous network of axons that formed the basis of all the integrative properties of the nervous system, while Cajal had provided the information that led to the formulation of the neuron doctrine that saw the nervous system as being made up of chains of discontinuous cells joined by polarized functional contacts that we now call synapses. The paper takes the form of an interview with Professor Cajal in the Grand Hotel Stockholm. His responses to questions posed by the imaginary interviewer are all taken from Cajal's own writings. 相似文献
20.
Elías Palti 《History and theory》2004,43(1):57-82
Recently, a call for the “return of the subject” has gained increasing influence. The power of this call is intimately linked to the assumption that there is a necessary connection between “the subject” and politics (and ultimately, history). Without a subject, it is alleged, there can be no agency, and therefore no emancipatory projects—and, thus, no history. This paper discusses the precise epistemological foundations for this claim. It shows that the idea of a necessary link between “the subject” and agency, and therefore between the subject and politics (and history) is only one among many different ones that appeared in the course of the four centuries that modernity spans. It has precise historico‐intellectual premises, ones that cannot be traced back in time before the end of the nineteenth century. Failing to observe the historicity of the notion of the subject, and projecting it as a kind of universal category, results, as we shall see, in serious incongruence and anachronisms. The essay outlines a definite view of intellectual history aimed at recovering the radically contingent nature of conceptual formations, which, it alleges, is the still‐valid core of Foucault's archeological project. Regardless of the inconsistencies in his own archeological endeavors, his archeological approach intended to establish in intellectual history a principle of temporal irreversibility immanent in it. Following his lead, the essay attempts to discern the different meanings the category of the subject has historically acquired, referring them back to the broader epistemic reconfigurations that have occurred in Western thought. This reveals a richness of meanings in this category that are obliterated under the general label of the “modern subject”; at the same time, it illuminates some of the methodological problems that mar current debates on the topic. 相似文献