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This paper demonstrates the results of analyses of Cladocera, pollen, plant macrofossil, lithological and radiocarbon data recovered from a mire located in the Rawka River valley in central Poland. These studies permit to recognise the development of hydrology phases in Kopanicha mire and give insight into Holocene fluvial dynamics of the system; radiocarbon dating partly allowed da-ting of the patterns of Holocene valley floor development of the Rawka River. The Kopanicha mire was formed during the Atlantic period. At that time, an oxbow lake formed, becoming a mire during the Subboreal and possibly Subatlantic periods. The high sensitivity of the oxbow lakes, fens, fauna, and flora remains to climate variations - especially to changes in water level connected with the ag-gradation-erosion cycle of rivers - allows the reconstruction of the palaeoecological changes that oc-curred in the mire. The frequency and timing of hydroclimatic oscillations at Kopanicha show strong similarities to records from other sites in Poland. Changes in Cladocera frequency and plant assem-blages were mostly influenced by the Rawka River which controlled the hydrological regime of the mire. The main factors controlling the presence of Cladocera taxa were the water level and the pres-ence of favourable conditions in the mire (e.g. pH, vegetation). Most of the changes occurred in re-sponse to climate changes, but some of them were connected with local factors.  相似文献   
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Two analytical models for unreinforced masonry (URM) buildings are proposed with the aim to simulate their seismic response and to estimate corresponding vulnerability functions. The proposed models are implemented in SAP 2000 nonlinear software to obtain capacity curve parameters for representative Indian URM buildings, based on a field survey and statistical analysis. Vulnerability functions are estimated using the obtained capacity curves. Damage Probability Matrices (DPMs) are obtained using the approximate PGA-intensity correlation relationship as per Indian seismic building code and are compared with the commonly used intensity scales and empirical damage data observed after the 2001 Bhuj earthquake.  相似文献   
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We present novel imaging results from a non-invasive examination of three ‘pattern-welded’ swords from the Viking Age belonging to the National Museum of Denmark, using white beam and energy resolved tomographies with neutrons. Pattern-welded blades are made by forge welding together thin strips of iron and steel that were twisted and joined in various ways, producing a decorative pattern on the surface. The study shed light on the inner structure of the composite material and manufacturing techniques of these admired examples of past technology, revealing some otherwise invisible details of their assembly methods, phase distribution and extent of the corrosion.  相似文献   
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Many Neolithic and Bronze Age cultural layers and pile fields embedded in sediments at the shorelines of pre-alpine lakes in France, Switzerland, Germany, Austria, and Italy (in part UNESCO World Heritage Sites), are threatened by littoral erosion which is partly caused by human agency. Based on measurements of the wave field at four prehistoric sites on Lake Constance (Germany, Switzerland) we discuss the role of passenger ship navigation. We also review the stability and ecological compatibility of archaeological preservation control fills on the littoral platform of Lake Constance, and we make some recommendations for future preservation measures.  相似文献   
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The early sedimentological and ecological developmental stages of a late Vistulian lake in the ?abieniec swamp near ?ód? (central Poland) were analysed by radiometric dating, changes in the frequency of specimens and species composition of Cladocera and multivariate statistical analysis (DCA). The longevity of the lake resulted in a fairly complete sedimentary record from approximately 22 ka to 11 ka cal BP. Species composition and the variability in the frequency of Cladocera specimens has made it possible to distinguish eleven zones of their development, which are well correlated with radiocarbon data. The results were compared to those from other sites of north and central Europe. The initial Cladocera development comprises the richest and oldest late Vistulian Cladocera record in Europe. These cladoceran assemblages show that a deep, oligotrophic, moderately cold-water lake was present at the beginning. It appears that the cladoceran development was mainly due to climate change, but also to changes in locally prevailing conditions in the water body. The high frequency of cladocerans, as well as the presence of cladoceran taxa preferring warmer water, was noted before approximately 16 ka BP. The biota suggests that the Oldest Dryas cooling was not severe and fairly variable in terms of humidity and temperature. The changes in Cladocera composition give evidence of what is described as the Intra-Bølling Cold Oscillation. It is also concluded that the Bølling is represented by two phases in the ?abieniec lake sediments.  相似文献   
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Tarsal coalition (TC) is defined as an abnormal fusion of two or more tarsal bones. The fusion may be fibrous, cartilaginous or osseous and can be congenital or acquired in response to infection, articular disorders, trauma, neoplasm or surgery. We report a case of a talocalcaneal (TCC) type of tarsal coalition in a medieval skeleton from Northwest Germany dating to ca. 1050 AD. The fusion is of osseous type. Plain AP radiographs and computed tomography confirmed the macroscopic diagnosis. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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The question on how regional clusters renew themselves and start a new cycle of prosperity is of vital interest for affected companies, politicians and regions. Recently, the idea of renewing clusters has been conceptualized within the cluster life cycle (CLC) literature. CLC approaches generally assume that cluster renewal is widely driven cluster-internally through agent capability building processes and the systemic utilization of novelty. Critique from other authors highlights the neglected role of the external environment in the CLC literature. This article sheds light on renewal processes in two German agricultural engineering clusters. It is shown that in the case of a farm trailer cluster renewal can be widely explained cluster-internally, while in the case of a stable technology cluster that diversified into the field of biogas technology, internal factors played a less significant role and much of the development was driven externally by political decisions on the national level. Possible explanations for diverging roles of cluster-internal and external factors lie in the differences in the stage of the novel technologies’ development and the complexity of the novel technology.  相似文献   
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