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1.
Effective catchment monitoring requires an integrative approach for selecting remotely sensed data to monitor land‐cover change. Catchment analyses and monitoring requirements in the Maroochy and Mooloolah River Catchments (south‐east Queensland) were addressed by linking government and community information needs to appropriate scales of remotely sensed data and processing routines. A hybrid image classification approach applied to Landsat Thematic Mapper image data acquired in 1988 and 1997 provided catchment scale land‐cover maps (with accuracies of 73% and 84%). Land‐cover change maps derived from post‐classification comparison provided information on the spatial distribution and type of land‐cover changes between 1988–1997. Land‐cover change was dominated by activities related to urban residential expansion (suburban and rural residential) and agricultural expansion (sugar cane farms). Significant spatial variations in the geometric registration accuracy of the image data sets and classification accuracies produced moderate to low change detection accuracies. However, the framework and community consultation used for selecting and processing data ensured the resource managers and community groups were fully aware of the limitations of the land‐cover change mapping process and that the output images were suitable for incorporating in resource monitoring activities.  相似文献   

2.
The Al‐Qutainah stone with its bas‐relief decoration was found in a secondary position, reused through time. The object is clearly a facing stone, originally part of an Umm an‐Nar period tomb, and was subsequently repeatedly reused for making new engravings. While working out the sequence of images it became clear that the very first image was a pair of human figures. This artwork is associated to grave architecture and therefore dates to the Umm an‐Nar period. Two models of interpretation can be suggested, the image of a human pair or the image of a supplicant and deity. Changes in the original meaning of the image indicate conceptual changes in subsequent periods, most probably alterations in the underlying social structure. The importance of the Qutainah stone is not solely due to rare monumental human figurative expression of the period in Oman; furthermore, the find spot in the Adam region is at a distance from the central location of Umm an‐Nar culture that has so far emerged.  相似文献   

3.
The aim of the present work is to characterize plasters from Ptolemaic baths recently discovered in front of the Karnak temple complex, by the excavations of an Egyptian–French team. The characterization was carried out by means of optical microscopy (OM), scanning electron microscopy (SEM) equipped with an energy‐dispersive X‐ray detector (EDS), X‐ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FT–IR). The results allowed the identification of the chemical composition and structure of these plasters. In addition, samples of red, yellow, black and white pigments were examined and identified. The results helped in providing an image concerning some materials used during the Ptolemaic era in ancient Egypt.  相似文献   

4.
基于文本挖掘的古镇旅游形象感知研究——以朱家角为例   总被引:5,自引:0,他引:5  
摘要:本文采用文本挖掘方法分析了新浪博客中关于朱家角的2633篇博文,根据词频统计结果,将游客对朱家角的旅游感知形象划分为地理位置形象、旅游地类型形象和地方性形象3种,其中旅游地类型形象涵盖词条数最多、频次最高,这表明朱家角作为江南古镇的类型形象强于朱家角的地理位置形象和地方性形象。通过共现分析发现,江南古镇的名称常常多个同时出现在博文中,这也表明朱家角与其他江南古镇的竞争表现在类型形象上,而非表现为与某特定古镇的竞争。结合长尾理论,本文发现,游客对朱家角旅游形象的感知呈现出“长尾”特征,同时在形象曲线的尾部出现了“非利基”形象,开发小众旅游产品时需要对出现在长尾中的形象进行仔细甄别。本文提出,在江南古镇整体氛围塑造的基础上,融入老上海元素和开发创意文化旅游产品,可以作为朱家角进行旅游产品差异化开发的一种方式。  相似文献   

5.
Tumlehed is the most well‐preserved and complex prehistoric rock painting in the coastal region of south‐west Sweden. Originally reported and described in 1974, we re‐documented the panel using digital and IR photography, DStretch image enhancement software, and non‐destructive PXRF spectroscopy. This re‐documentation revealed a more complex image inventory with several previously unknown motifs and image details. The new data provide a better basis for identifying motif categories, the organization of the panel, the chronological sequence, and different frequentation periods. We report on the only known boats with an elk‐head stem in southern and western Scandinavian rock art, the emergence of rock art boat depictions in the region, and evidence for long‐distance maritime journeys and sea‐mammal hunting in the later Stone Age. Comparisons to similar images with shoreline data in Fennoscandia narrow the time range for the date of the painting to 4200–2500 BC.  相似文献   

6.
This paper proposes an empirical climate classification method based on the application of multivariate statistics. In this method, the technique of supervised and unsupervised image classification is used to classify the data and define climatic units. envi software is used to perform the image classification, specifically, the Iterative Self‐Organizing Data Analysis Technique algorithm. Supervised classification is also applied based on reference variables, fundamental parameters and a classifier. The obtained results display greater objectivity, reliability, operability, accessibility and reproducibility than previous climate classifications devised for the region of Andalusia (Spain), taking into account that these previous classifications were not based on quantitative criteria.  相似文献   

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This article proposes a geostatistical solution for area‐to‐point spatial prediction (downscaling) taking into account boundary effects. Such effects are often poorly considered in downscaling, even though they often have significant impact on the results. The geostatistical approach proposed in this article considers two types of boundary conditions (BC), that is, a Dirichlet‐type condition and a Neumann‐type condition, while satisfying several critical issues in downscaling: the coherence of predictions, the explicit consideration of support differences, and the assessment of uncertainty regarding the point predictions. An updating algorithm is used to reduce the computational cost of area‐to‐point prediction under a given BC. In a case study, area‐to‐point prediction under a Dirichlet‐type BC and a Neumann‐type BC is illustrated using simulated data, and the resulting predictions and error variances are compared with those obtained without considering such conditions.  相似文献   

9.
The solubility of quartz has been measured in a wide range of salt solutions at 800°C and 0.5 GPa, and in NaCl, CaCl2 and CsCl solutions and H2O–CO2 fluids at six additional PT conditions ranging from 400°C at 0.1 GPa to 800°C at 0.9 GPa. The experiments cover a wide range of compositions along each binary. At PT conditions where the density of pure water is low (0.43 g cm?3), addition of most salts produces an enhancement of quartz solubility at low to moderate salt concentrations (salt‐in effect), although quartz solubility falls with further decrease in XH2O. At higher fluid densities (0.7 g cm?3 and greater), the salt‐in effect is generally absent, although this depends on both the cation present and the actual PT conditions. The salt‐in effect is most readily produced by chloride salts of large monovalent cations, while CaCl2 only produced a salt‐in effect at the most extreme conditions of high‐T and low‐P investigated (800°C at 0.2 GPa). Under most crustal conditions, the addition of common salts to aqueous fluids results in a lowering of quartz solubility relative to that in pure water (salt‐out effect). Comparing quartz solubility in different fluids by calculating XH2O on the basis that all salts are fully associated under all conditions yields higher quartz solubility in solutions of monovalent salts than in solutions of divalent salts, absolute values are also influenced by cation radius. Quartz solubility measurements have been fitted to a Setchenow‐type equation, modified to take account of the separate effects of both the lowering of XH2O and the specific effects of different salts, which are treated as arising through distinct patterns of non‐ideal behaviour, rather than the explicit formation of additional silica complexes with salt components. Quartz solubility in H2O–CO2 fluids can be treated as ideal, if the solvation number of aqueous silica is taken as 3.5. For this system the solubility (molality) of quartz in the binary fluid, S is related to its solubility in pure water at the same PT conditions, So, by: Quartz solubility in binary salt systems (H2O–RCln) can be fitted to the relationship: where salt concentration mRCln is expressed as molality and the exponent b has a value of 1 except under conditions where salting‐in is observed at low salt concentrations, in which case it is <1. Under most crustal conditions, the solubility of quartz in NaCl solutions is given to a good approximation by: We propose that quartz solubility in multicomponent fluids can be estimated from an extended expression, calculating XH2O based on the total fluid composition (including dissolved gasses), and adding terms for each major salt present. Our experimental results on H2O–NaCl–CO2 fluids are satisfactorily predicted on this basis. An important implication of the results presented here is that there are circumstances where the migration of a fluid from one quartz‐bearing host into another, if it is accompanied by re‐equilibration through cation exchange, may lead to dissolution or precipitation of quartz even at constant P and T, with concomitant modification of the permeability structure of the deep crust.  相似文献   

10.
We examine the post‐seismic change in the groundwater level following the 1999 (Mw = 7.5) Chi‐Chi earthquake in central Taiwan, as recorded by a network of 70 evenly distributed hydrological stations over a large alluvial fan near the epicenter. Four types of post‐seismic responses may be distinguished. In type 1, the groundwater level declined exponentially with time following a coseismic rise. This was the most common response in the study area and occurred in unconsolidated sediments on the Choshui River fan. In type 2, the groundwater level rose exponentially with time following a coseismic fall. This occurred in the deformed and fractured sedimentary rocks in the foothills near the Chelungpu fault that ruptured in the Chi‐Chi earthquake. In type 3, the groundwater level continued to decline with time following a coseismic fall. This also occurred in the deformed and fractured sedimentary rocks near the ruptured fault. Finally, in type 4, the groundwater level, following a coseismic rise, stayed at the same level or even rose with time before it eventually declined. This occurred mostly in unconsolidated sediments along the coast of central Taiwan and along the Peikang Stream. We analyze these post‐seismic responses by using a one‐dimensional model. Together with the results from well test, the analysis show that the type 1 response may be explained by an aquifer model with coseismic recharge and post‐seismic subhorizontal discharge across a length of 500–5000 m; the type 2 response may be explained by a model of coseismic discharge and post‐seismic recharge from surface water; the type 3 response may be explained by a model of coseismic discharge and post‐seismic subhorizontal discharge across a length of 500–5000 m; and the type 4 response may be explained by a model of coseismic recharge and sustained post‐seismic recharge from surface water. The characteristic time for the post‐seismic changes is similar to that for the groundwater‐level decline during dry seasons before the earthquake, suggesting that there was no earthquake‐induced changes in the aquifer properties (i.e. hydraulic conductivity), confirming the earlier results from recession analyses of the post‐seismic streamflow elsewhere after several earthquakes.  相似文献   

11.
Academic research on contemporary Dutch nationalism has mainly focused on its overt, xenophobic and chauvinist manifestations, which have become normalised since the early 2000s. As a result, less radical, more nuanced versions of Dutch nationalism have been overlooked. This article attempts to fill this gap by drawing attention to a peculiar self‐image among Dutch progressive intellectuals we call anti‐nationalist nationalism. Whereas this self‐image has had a long history as banal nationalism, it has come to be employed more explicitly for political positioning in an intensified nationalist climate. By dissecting it into its three constitutive dimensions – constructivism, lightness and essentialism – we show how this image of Dutchness is evoked precisely through the simultaneous rejection of ‘bad’ and enactment of ‘good’ nationalism. More generally, this article provides a nuanced understanding of contemporary Dutch nationalism. It also challenges prevalent assumptions in nationalism studies by showing that post‐modern anti‐nationalism does not exclude but rather constitutes essentialist nationalism.  相似文献   

12.
A new wave of neo‐Boasian anthropologists advocate retrieving Boas’s sense of historicity. In his theoretical writings, and especially his early exchange with Mason and Powell in 1887, Boas linked history to Alexander von Humboldt’s “cosmographical” method and to inductive science, accusing evolutionists of reasoning deductively on the basis of artibrary classifications. Boas, on the contrary, would not classify but would consider the “individual phenomenon”. Strangely enough, Boas’s presentation of his scientific procedure has more or less been taken at face value, and I question this Boas‐centric view of Boas. Examining Boas’s theoretical statements, his onslaught against evolutionism and his ethnographic practice, I find the accusation of deductive reasoning against evolutionists totally polemical. Furthermore, I discover neither induction nor history or cosmography in his practice, but a Linnaean‐type natural history. In brief, I uncover an inverse image of what Boas presented of himself, and no basis whatsoever for retrieving a historicity for contemporary anthropology.  相似文献   

13.
In 1937 a large barrow in north‐east Yorkshire was excavated by Mrs H. W. and Dr F. Elgee. A primary deposit comprising a ‘canoe’‐shaped log coffin and what were described as two ‘log boats’ or ‘canoes’ was uncovered beneath the mound. The burial did not survive; however, the ‘canoe’‐shaped coffin was found to contain an Early Bronze Age Merthyr Mawr‐type dagger, flints and some hazelnuts. Subsequently, a cremation was inserted into the top of the mound. This was accompanied by a Camerton‐Snowshill‐type dagger, a stone battle axe, a copper alloy pin, an accessory vessel and fragments from a Collared Urn. As part of a log coffin radiocarbon‐dating project, one of the hazelnuts was radiocarbon‐dated to 2008–1772 cal BC (95.4%) and a fragment of cremated bone from the secondary burial was dated to 1890–1741 cal BC (93.2%). This paper discusses the dating results and reconsiders the interpretation of the log coffin as a boat.  相似文献   

14.
During the last two years travel agents have changed from being relatively unregulated (outside New South Wales) to regulated in terms of licensing and compensation fund membership requirements. Why has this happened during a period when political debate has centred on deregulation? It is a premise of this paper that arguments in favour of deregulation rest on an image of the State as a prison for private entre‐preneurship; and arguments in favour of regulation rest on an image of the State as a protector of the consumer and public interest Both images are superficial and belie the nature of State‐capital‐consumer relationships and ideologies. Underlying each are rationalist assumptions which suggest that the State and industry are static, ahistorical objects; that governments have unambiguous intentions; and that regulation and deregulation are always successful. Each of these assumptions is questioned. By focusing on a history of travel agency regulations, this paper endeavours to uncover that which these images obscure in the deregulation debate.  相似文献   

15.
Recent excavations by V.I. Sarianidi in the so‐called ‘royal necropolis’ of Gonur Depe North, in southern Turkmenistan, have brought to light the first unequivocal example of an Umm an‐Nar‐type soft‐stone compartmented vessel ever found in Central Asia. The find is discussed in light of other evidence of links between Central Asia, south‐eastern Arabia and Bahrain.  相似文献   

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This paper presents the results of a multispectral reflectometry and ultraviolet (UV) fluorescence study on the entrance wall of the Tomb of the Blue Demons in the Necropolis of Monterozzi (450–430 bc ) in Tarquinia (Viterbo, Italy), which is a UNESCO site. The technique is based on the acquisition of a multispectral set ranging from 10 to 25 images, acquired at wavelengths between 370 and 1120 nm, with a spectral width of 50 nm per image, using both halogen lamps for visible and infrared images and high‐purity UV diodes for fluorescence. Blind‐source separation algorithms were then applied to the whole image set to extract from the resulting images the details not otherwise visible in the single spectral images. The multispectral technique presented was tested and improved upon over the last decade on ancient Etruscan and Roman wall paintings and, because of its quickness and cost‐effectiveness, it can now be proposed as a powerful tool for the study of poorly conserved archaeological wall paintings and a preliminary diagnostic survey before any future conservation intervention on them.  相似文献   

19.
Understood as mimetic portrayals of the image of unlimited good projected by European colonial culture, Melanesian ‘cargo cults’ are therefore viewed as ‘irrational’ within indigenous understandings. Consequently, Western anthropological discourse has sought to functionally normalize and nativize ‘cargo cult’ behaviors at the expense of denying their non‐rational character. The result has been a lexical and semantic uncertainty and explanatory instability in ‘cargo cult’ discourse that can be analyzed as a type of discursive ‘madness.’ A strategy of reading the ‘madness’ of ‘cargo cult’ discourse is outlined and applied to key anthropological texts, in particular Peter Worsley's The Trumpet Shall Sound.  相似文献   

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