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1.
This paper engages with recent geographical debates on alternative economic practices, arguing that insufficient attention has been paid to the scale at which they operate. Through an analysis of recent attempts to 'fix' economic activity at a scale felt to be normatively desirable through alternative currencies, the paper argues that when attempting to build non-capitalist practices, scale matters. The paper discusses processes of financial structuration that limit and channel these spaces through an analysis of localized alternative networks in the UK (Local Exchange Trading Schemes – LETS) and the geographically wider barter networks in Argentina.  相似文献   
2.
Deceptively Similar. Remarks on the History of Model Experiments. The article argues for a reconsideration of what has been called ‘model experiments’ or ‘mimetic experiments’. After providing a short overview of the historical developments and the occurences of such types of experiments, three aspects pertaining to their practical functions are discussed. First, the aspect of control: Model experiments are often employed to get a grasp on phenomena that are otherwise beyond the control of human actors. Second, their aesthetic dimension: Model experiments often employ aesthetic strategies that, far from being epistemic obstacles, establish their function as models and may generate new areas of research. Third, meta‐theories: The practice of experimenting on models is often accompanied by discussions about their representativeness. Albeit triggered by problems in local contexts, this self‐reflective discourse did acquire a more general relevance with the formulation of scaling laws in the 19th century.  相似文献   
3.
The presence and properties of long‐range correlations in temperature data reflect interactions among climate components; therefore, the quantitative characterization of scaling aspects of temperature patterns is important to climate research and can serve as an effective constituent of tests for climate models. The article presents the results of a study using multiscale characterization of daily atmospheric surface temperature patterns in Atlantic Canada. Important influences in this region are exerted from the west (the Pacific Ocean), the south (the Gulf of Mexico) and the north (the Arctic), while a significant easterly impact is due to the Atlantic Ocean; the corresponding processes involve a wide range of spatial and temporal scales. The objective of the present study of long‐term temperature recordings was to evaluate the scaling properties produced in this geographical context. The data consist of homogenized daily atmospheric temperature time series recorded in stations from Atlantic Canada over a time interval of more than 100 years. Detrended fluctuation analysis (DFA) was applied both to maximum and minimum temperature records. The atmospheric temperature pattern produced by the interplay of factors of different strengths and dominating various time‐space scales was found to be characterized by consistent scaling properties, expressed over time intervals ranging from months to decades. Higher values of DFA scaling exponents were obtained for minimum temperature compared to maximum temperature records. Site‐specific properties include stronger pattern persistence—higher DFA exponents—for oceanic than for coastal locations; persistence tends to decrease with increasing distance from the coast for distances up to 10 kilometres. Scaling exponents tend to increase with decreasing difference between average minimum and maximum temperature, which may be relevant for the assessment of future changes in pattern variability if climate change involves modified contrasts between minimum and maximum temperature values.  相似文献   
4.
Between 1902 and 1904 an epidemic of cholera, fuelled initially by the operations of the Philippine-American War (1899–1902), swept through the Philippine Islands in two waves. In earlier papers, the authors showed that spatially contagious spread dominated the waves at the geographical levels of province, island and nation (Smallman-Raynor and Cliff 1998a, b). To explore the visualization and analysis of epidemic transmission in an alternative metric, the present paper uses multidimensional scaling (MDS) to translate the spread corridors followed by the waves from conventional geographical space into non-Euclidean cholera spaces. The re-mapping confirms the importance of contagious diffusion in the spread of the epidemic, but also picks out the moments in time in which spread driven through the population hierarchy switched in. In addition, the analysis illustrates the utility of constructing non-Euclidean spaces to identify disease diffusion processes.  相似文献   
5.
Snyder and Whitaker’s (2013) discussion of Penfield’s homunculus in a recent issue of this journal was stimulating but I believe mistaken in several ways. This letter clarifies the diagram’s supposed ambiguity, highlights a largely overlooked problem with improper scaling and challenges the authors’ argument for the superiority of the 1950 version of the image.  相似文献   
6.
Classification of earthquake strong ground motion (SGM) records is performed using fuzzy pattern recognition to exploit knowledge in the data that is utilised in a genetic algorithm (GA) search and scaling program. SGM records are historically treated as “fingerprints” of certain event magnitude and mechanism of faulting systems recorded at different distances on different soil types. Therefore, databases of SGM records of today present data of complex nature in high dimensions (many of the dimensions—or SGM parameters in time and frequency domain—are presently available from different archives). In this study, simple ground motion parameters were used but were combined and scaled nonlinearly such that the physical properties of the data could be preserved while reducing its dimensionality. The processed data was then analysed using fuzzy c-means (FCM) clustering method to explore the possibility of meaningfully representing earthquake SGM data in lower dimensions through finding subsets of mathematically similar vectors in a benchmark database. This representation can be used in practical applications and has a direct influence on the processes of synthesising ground motion records, identifying unknown ground motion parameters (e.g. soil type in this study), improving the quality of matching SGM records to design target spectra, and in rule generalisation for response. The results showed that the stochastic behaviour of earthquake ground motion records can be accurately simplified by having only a few of motion parameters. The very same parameters may also be utilised to derive unknown characteristics of the motion when the classification task on “training” records is performed carefully. The clusters are valid and stable in time and frequency domain and are meaningful even with respect to seismological features that were not included in the classification task.  相似文献   
7.
张紫琼  Rob Law  刘挺 《旅游科学》2012,26(5):76-84
本文基于对香港居民的大规模电话调查,采用最优尺度回归模型,探讨出游动机和人口统计特征如何影响香港居民对旅游重要性的感知以及人口统计特征如何影响香港居民的出游动机。回归结果显示:休闲放松和发掘新事物是影响旅游重要性感知的主要旅游动机,家庭月收入和受教育程度是影响旅游重要性感知的主要人口统计特征;与亲朋好友聚会、社交、休闲放松、逃脱日常事务和发掘新事物动机最相关的人口统计特征分别是家庭月收入、年龄、家庭月收入、年龄和受教育程度,而性别对香港居民的各种出游动机无显著影响。  相似文献   
8.
Investigation of modern biometric data indicates that it may be possible to distinguish wildcats from house cats in many instances. Applying the log‐ratio (log‐difference) technique to archaeological samples from medieval northern Europe, and to mixed samples of wildcats and house cats, shows that the differentiation may not always be clear, and the possibility that some samples include hybrids is discussed. The technique is applied to samples from the Orkney Islands to demonstrate that single wildcat specimens can be identified in small samples. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
9.
We recognize a new style of Mississippian-period art in the North American Southeast, calling it Holly Bluff. It is a two-dimensional style of representational art that appears solely on containers: marine shell cups and ceramic vessels. Iconographically, the style focuses on the depiction of zoomorphic supernatural powers of the Beneath World. Seriating the known corpus of images allows us to characterize three successive style phases, Holly Bluff I, II, and III. Using limited data, we source the style to the northern portion of the lower Mississippi Valley.  相似文献   
10.
Stone tools tend to be classified according to a mix of functional, morphological, and technological attributes. This practice results in confusions when large-scale assemblage comparisons are made with the aim of investigating phylogenetic relationships, as functional and cultural information is aggregated. It is argued here that functional criteria must be assessed separately, and that resharpening, as a uniform, repeated, conscious behavioral process of tool maintenance that indexes use and function, can provide a solution to this problem. The subject of this article is a quantitative method for extracting and comparing resharpening trajectories. The method is an adaptation of ontogenetic scaling methods from biology, and is based on obtaining a mathematical representation of shape and size, and finding a relationship between the two. Elliptical Fourier analysis is applied to stone tool contours in order to extract shape information, and then a series of regressions of shape on size provide trajectory vectors. The angles between these are then calculated and subjected to a variety of multivariate statistical tests. A case study involving several European Middle Paleolithic bifacial and unifacial tool assemblages is presented. The results show that resharpening and maintenance can be independent of morphology and technology, suggesting that there are strong grounds for focusing on functional systematics separately.  相似文献   
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