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971.
基于专利地图的旅游业专利研究 总被引:2,自引:0,他引:2
旅游业专利技术是衡量旅游业技术创新的重要指标,本文利用专利地图理论和方法,直观展示旅游业专利的总体趋势、技术生命周期、国际专利分类,并深入挖掘旅游业专利信息。 相似文献
972.
Fernando Rubiera Morollón Victor M. González Marroquin José Luis Pérez Rivero 《European Planning Studies》2016,24(1):207-226
Urban sprawl has a major impact on the environment, public health and the socio-economic evolution of cities. The causes are numerous, being mainly related to the generalized use of the automobile in modern cities. Urban sprawl has been especially relevant in US cities since the 1950s, rapidly spreading to other cities in the rest of the world. This paper studies the case of Spain using recent data. Spanish cities have grown rapidly over the 90s and 2000s. The country has completed the process of urbanization and has suffered the effects of a major real estate bubble. In this context, we are interested in measuring and explaining where and why urban sprawl has appeared in Spanish cities. Digital mapping carried out around the year 2000 providing full coverage of Spain is used to calculate an Urban Sprawl Index. It is applied to all urban areas and municipalities throughout the country, providing an objective, comparable measurement of sprawl and identifying which areas are most affected by this phenomenon. A second stage of analysis is conducted in an attempt to explain the causes of the differences in sprawl among Spanish cities with a regression model based on the literature. We have found that the cases most affected by sprawl are the latest urban developments on the Mediterranean coast as well as certain areas in the vicinity of large cities: the mountains to the north of Madrid and the coastline near Barcelona and Valencia. In some cases, urban sprawl is starting to become a problem for the environment and urban sustainability, with important consequences for the future evolution of the affected cities. 相似文献
973.
Robert Krzysztofik Iwona Kantor-Pietraga Tomasz Spórna Weronika Dragan Valentin Mihaylov 《European Planning Studies》2019,27(8):1646-1660
The growing role of logistics in the economic space of large metropolises is visible in an increasing number of objects of this kind as well as in their high spatial concentration. Taking into account these circumstances, a phenomenon known as ‘logistics sprawl’ is considered in the article. This is one of two problems concerning the development of logistics in metropolitan areas. Studying the Katowice conurbation in Poland, the authors note, however, that in this region the opposite phenomenon, which they define as a ‘logistics anti-sprawl’, is more noticable. Its characteristic feature is a location of logistics facilities not in the outer zone of the conurbation, but in its core. This phenomenon undoubtedly differs from the patterns of localization of logistics facilities in all major CEECs. It is caused by some chief factors which are disscused in the paper. Therefore, an attention is drawn on the period of socialist development of the region, its contemporary postindustrialism, urban shrinkage, as well as the polycentricity of the conurbation. The crucial question whether the expected reduction of the ‘sprawl logistics’ phenomenon may be based on the development model observed in the Katowice conurbation is also discussed in the article. 相似文献
974.
Martin Biskowski 《Archaeological and Anthropological Sciences》2017,9(1):29-38
Like studies of craft production, research on food production has significant implications for understanding the economic organization of past societies. This paper highlights the tools of maize (Zea mays) processing and cooking as a constructive avenue to examine aspects of food production at Teotihuacan during the Terminal Formative and Classic Periods (100 BC–AD 650). By analyzing the spatial distribution of comales, metates and manos recovered from the Teotihuacan Mapping Project, this study investigates the notion that edible maize products were produced through specialized labor. Two notable patterns are observed. First, the aggregation of comales along the Street of the Dead during the Miccaotli phase (AD 100–170) suggests that tortilla preparation fueled large public work projects, feeding the workers, their families, and other dependents of the state. Secondly, the spatial aggregation of grinding stones, manos and comales in seven concentrated areas within the Classic Period (AD 170–650) occupation of the city suggest that several apartment compounds, possibly entire barrios, may have specialized in the production of tortillas and other finished maize foods for exchange. Such a pattern may have resulted from the costly labor and materials required for the production of tortillas, favoring economies of scale. Several areas within the city conspicuously possessing low frequencies of maize processing artifacts suggest that some sectors were dependent on specialized labor from outside the household for daily needs. Together, these data suggest that food production was a specialized activity at Teotihuacan and increase our understanding of the economic organization of the ancient metropolis. 相似文献
975.
Tobias Smith Felice C. Ponzo Antonio Di Cesare Stefano Pampanin David Carradine Andrew H. Buchanan 《Journal of Earthquake Engineering》2014,18(1):147-167
This article describes tests investigating a feasible source of passive damping for post-tensioned glue-laminated (glulam) timber structures. This innovative structural system adapts precast concrete PRESSS technology [Priestley et al., 1999] to engineered wood products combining the use of post-tensioned tendons with large timber members. Current testing is aimed at further improvement of the system through additional energy dissipation. Testing has favorably compared glue-laminated timber (not previously implemented in this way) with laminated veneer lumber (LVL) used in New Zealand. After initial benchmark testing with post-tensioning only, a simple, minimally invasive and replaceable type of hysteretic damper was added. 相似文献
976.
977.
The fat‐ and nutrient‐rich marrow of animal bones can be extracted using different techniques. Passive hammerstone percussion has been the primary focus of experimental bone breaking and the main analogy to understand archaeological bone breakage. Here, the term ‘passive’ is applied because the bone to be broken passively receives the impact from a hammerstone. In addition to this technique, there is another bone‐breaking method that also requires direct percussion, but in an active way. This method is percussion by ‘batting’, in which the bone is actively hit against an anvil until the bone breaks. This technique has rarely been considered at an experimental level and, therefore, has been omitted in the majority of the archaeological interpretations of faunal assemblages with pre‐use of fire technologies. In this study, we attempt to analytically characterize this type of bone‐breaking technique through a systematic comparison with hammerstone percussion. The applied statistical tests will allow us to distinguish some diagnostic modifications, such as the outlines of the fracture planes and the type of notches or their location with respect to the longitudinal axis of the bone. These features and their proportions allow the consideration of the use of this technique in Pleistocene anthropogenic faunal assemblages. 相似文献
978.
D. Watkinson M. Rimmer Z. Kasztovszky Z. Kis B. Maróti L. Szentmiklósi 《Archaeometry》2014,56(5):841-859
Chloride (Cl) ions diffuse into iron objects during burial and drive corrosion after excavation. Located under corrosion layers, Cl is inaccessible to many analytical techniques. Neutron analysis offers non‐destructive avenues for determining Cl content and distribution in objects. A pilot study used prompt gamma activation analysis (PGAA) and prompt gamma activation imaging (PGAI) to analyse the bulk concentration and longitudinal distribution of Cl in archaeological iron objects. This correlated with the object corrosion rate measured by oxygen consumption, and compared well with Cl measurement using a specific ion meter. High‐Cl areas were linked with visible damage to the corrosion layers and attack of the iron core. Neutron techniques have significant advantages in the analysis of archaeological metals, including penetration depth and low detection limits. 相似文献
979.
980.
Charles Higham Thomas Higham Roberto Ciarla Katerina Douka Amphan Kijngam Fiorella Rispoli 《Journal of World Prehistory》2011,24(4):227-274
White and Hamilton (J World Prehist 22: 357–97, 2009) have proposed a model for the origin of the Southeast Asian Bronze Age founded on seven AMS radiocarbon determinations from
the Northeast Thai site of Ban Chiang, which would date the initial Bronze Age there to about 2000 BC. Since this date is
too early for the derivation of a bronze industry from the documented exchange that linked Southeast Asia with Chinese states
during the 2nd millennium BC, they have identified the Seima-Turbino 3rd millennium BC forest-steppe technology of the area
between the Urals and the Altai as the source of the Southeast Asian Bronze Age. We challenge this model by presenting a new
chronological framework for Ban Chiang, which supports our model that the knowledge of bronze metallurgy reached Southeast
Asia only in the late 2nd millennium BC, through contact with the states of the Yellow and Yangtze valleys. 相似文献