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1.
Vertebral compression fractures are the most common osteoporotic fractures in postmenopausal women. Notwithstanding, its clinical diagnosis remains ambiguous. In paleopathological studies, vertebral fractures and/or deformations are frequently disregarded. When observed, vertebral compression fractures are usually recorded without the support of quantifiable and comparable protocols. As such, Genant's semi‐quantitative method for vertebral compression fracture assessment was applied to a large sample (N = 196) from the Coimbra Identified Skeletal Collection, Portugal, and the reliability of the method was tested. Vertebral fracture scoring agreement was evaluated with the kappa statistic and the per cent of agreement. Intra‐observer agreement was almost perfect, whereas inter‐observer agreement was substantial to almost perfect. The Genant's semi‐quantitative scoring methodology is easy to apply and highly reproducible; as such, it should be adopted as the standard method to score vertebral fractures in any paleopathological investigation. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
2.
Abstract

The authors argue that the publication of any new historical data series requires a formal estimate of its margins of error. We show how overall margins of error may be calculated for the standard forms of historical data series from information on the reliability of its components. The presentation of such margins of error should be transparent, allowing readers both to judge the estimate and to test the implications of applying different standards. An illustration is provided for Hoffmann's industrial output series for Britain, 1780–1831. The calculations emphasize the value of this approach to the recent debate on measuring growth rates during the British Industrial Revolution and suggest its merits more generally.  相似文献   
3.
基于手机数据可靠性分析的旅游城市功能空间识别研究   总被引:1,自引:0,他引:1  
赵莹  张朝枝  金钰涵 《人文地理》2018,33(3):137-144
随着移动通信和移动互联网的普及,带有地理空间信息的“大数据”受到人文地理学者的关注。本文关注手机移动数据的旅游研究价值,以张家界市武陵源区、慈利县为例,首先分析了通信公司漫游用户数、基站网流量和话务量代表实际游客量的可靠性程度,然后探讨了漫游用户数波动对大尺度行政区的功能空间反映,最后挖掘了网流量波动对小尺度基站区的功能空间识别。结果显示,漫游用户数仅在旅游区对实际游客量具有可靠性,基站网流量比话务量的可靠性更强;漫游用户数在旅游区的波动幅度更大;基站网流量的空间因子分析识别出日常居住区、重点旅游区等功能空间。  相似文献   
4.
Many faunal assemblages across southwest Asia contain the remains of multiple wild equid species, which may reflect individual prehistoric human populations' use of different hunting and/or landscape exploitation strategies. Accurate equid species assignments are therefore important. This paper tests the extent to which zooarchaeologists agree on equid species assignments made using commonly used zooarchaeological dental identification criteria. Seven zooarchaeologists individually use published criteria to assign species to equid teeth from Neolithic Çatalhöyük in central Anatolia, then use Fleiss' kappa to measure our reliability of agreement. We assess our degrees of agreement for species assignments made using scanned images versus actual specimens and for mandibular teeth versus maxillary teeth. Having failed to achieve significant agreement, we conclude that zooarchaeologists should be cautious about species assignments made using these methods. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
5.
This study developed an interview-based critical spatial thinking oral test and used the test to investigate the effects of Geographic Information System (GIS) learning on three components of critical spatial thinking: evaluating data reliability, exercising spatial reasoning, and assessing problem-solving validity. Thirty-two students at a large state university completed pre- and post-tests administered during the 2010 fall semester. This study found positive relationships between GIS learning and critical spatial thinking. We argue that the improvement can be attributed to students' experiences in a GIS course.  相似文献   
6.
National and international regulatory standards require industrial risk assessment, taking into account natural hazards including earthquakes, in the framework of Quantitative Risk Analysis (QRA). Seismic fragility analysis of industrial components may be carried out similarly as what has been done for buildings, even though some peculiar aspects require the development of specific tools. In the present paper a contribution to the definition of a rational procedure for seismic vulnerability assessment of standardised industrial constructions in a probabilistic framework is given. The method covers a range of components of the same structural type. Seismic reliability formulation for structures is used. Both seismic capacity and demand are considered probabilistic with the latter assessed by dynamic analyses. The application example refers to shell elephant foot buckling of unanchored sliding tanks. A regression-based method is applied to relate fragility curves to parameters varying in the domain of variables for structural design.  相似文献   
7.
Structures designed according to earlier codes with inadequate seismic provisions have not performed satisfactorily during recent earthquakes. The seismic performance of an existing three-storey reinforced concrete building designed according to the 1963 ACI 313-63 is evaluated and compared to the performance of a similar frame designed according to current code provisions. Non-linear static and dynamic analyses of the reinforced concrete frames are conducted. In this study, a probabilistic approach is adopted where a large number of artificially generated ground motion records is used as input motion to the structure. The results of the analysis indicated the probability of various degrees of damage to be expected when the existing frame is subjected to different ground motion levels. This information is useful in the design of the required rehabilitation scheme to provide an identified level of protection.  相似文献   
8.
故宫古建筑结构可靠性问题研究   总被引:1,自引:0,他引:1  
为保护故宫古建筑,采用归类汇总与理论分析相结合的方法,研究了故宫古建筑木结构的典型残损问题。基于大量现场勘查及理论分析结果,对故宫古建筑存在的典型可靠性问题进行了分类汇总,分析了产生这些问题的原因,提出了可行性加固建议。通过典型算例,对古建筑木结构加固方法进行了深入论证。结果表明:故宫古建筑木结构的柱子、斗栱、榫卯节点、梁架、屋顶、墙体等各部位都容易产生开裂、糟朽、变形、拔榫等可靠性问题并影响结构整体的稳定性能,而这些问题的产生原因主要与木结构的构造特征、木材材料性质及施工保养等因素有关;针对不同的可靠性问题,采取合理有效的加固方法,可提高古建筑结构整体的稳定性能。  相似文献   
9.
Seismic prevention and mitigation of historical centers have gained a central position within earthquake engineering topics, particularly in areas such as Italy, Greece, and Portugal. Many historical towns in these countries have been strongly damaged, due to the high quantity of old buildings and urban structures and infrastructures. In this article, these aspects are described, modeled, and investigated in terms of structural safety, the goal being the set-up of a comprehensive strategy for seismic prevention and mitigation of a whole historical center. The proposed approach is based on two relevant parts: the first is an urban risk assessment, the second is a prioritization of retrofitting interventions so as to optimally increase urban safety.

The effectiveness of the proposed methodology is shown with reference to a complex case study, the historical center of “Montebello di Bertona”. It is initially modeled as a series/parallel system and then studied by applying seismic reliability methods. Seismic retrofitting interventions are finally prioritized.  相似文献   

10.
The Uncoupled Modal Response History Analysis (UMRHA) method developed by Chopra et al. is modified in this paper to estimate damage to welded moment-resisting connections in a steel frame (MRSF) subjected to earthquake ground motions. The behaviour of these connections is modelled by a moment-rotation relationship that accounts for the cracking of the beam flange-to-column flange groove weld. The behaviour of the frame is approximated by a sequence of single-degree-of-freedom (SDOF) models for the first three modes to allow for the contribution of higher modes of vibration. The dynamic properties of these SDOF systems are determined by nonlinear static pushover analyses of the building frame. Because of the significant drop in connection strength caused by beam-to-column weld cracking, the pushover procedure uses a changing rather than invariant distribution of horizontal loads, while the structural responses are calculated from shapes that are based on the displaced shape of the frame after damage occurs. The accuracy of the method is demonstrated by a comparison with the results of a nonlinear time history analysis of the frame. This method can be used for rapid assessment of seismic damage or damage potential and to identify buildings requiring more detailed investigation.  相似文献   
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