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1.
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples.  相似文献   
2.
Ancient iron tie-rods are handcrafted elements with large geometric irregularities, due to production techniques (they are shaped by hammering and linked by hot-forging) and corrosion processes. In common practice, their cross section (that is one of the main parameter to assess their strength) is manually measured on site with a manual caliber. By analyzing a set of detailed three-dimensional (3D) digital surveys of real ancient tie-rods, this study provide an evaluation of the errors made by in-situ manual geometric measurements. In particular, it shows that, in some cases, manual on-site survey is sufficiently reliable and has errors that fall below 10%. Moreover, it shows that when tie-rods have high corrosion levels in hidden zones (typically those close or within the retaining walls) the on-site survey of visible parts only may produce far greater errors that exceed 100%, leading to a strong overestimation of the cross-section of the tie. The ongoing study is a first step toward the definition of correction coefficients to be applied to the on-site manual measurements of ancient tie-rods, with the final aim to improve the reliability of structural analyses.  相似文献   
3.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
4.
This study examines the interrelationship between external political support, internal organizational factors, and red tape, using a sample of information managers from state health and human service agencies. The study defines a red tape model and tests the model by structural equation modeling method. The study finds that political support has a direct effect on red tape. The higher the political support, the lower the level of red tape. The study also confirms an indirect effect of political support on red tape, mediated by developmental culture. Indirect effect through goal clarity has the correct sign but is not statistically significant. Practical recommendations are made for the political environment to provide the opportunity for managerial reforms that are often advocated.  相似文献   
5.
朱定秀 《安徽史学》2007,4(3):13-16
国家恐怖主义是由政府实施的恐怖主义,法西斯主义则是国家恐怖主义发展到登峰造极的产物.国家恐怖主义具有制度化、公开性和社会化的特点,并具有独裁政治,庞大的镇压机器,镇压性的特务机关,非人道的人身迫害,非战争状态下对大量人口的集体收监、屠杀或迫使其流亡,针对社会知名人士的暴力行为等构成要素.  相似文献   
6.
ABSTRACT

The interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes.  相似文献   
7.
The antiquity and context (site or feature type) are the two principal factors that act as a framework for interpreting charcoal and wood data from archaeological sites in the recreation of past woodland environments. This research addresses these parameters through the analysis of over 18,000 charcoal fragments from 57 archaeological excavations carried out along a 61?km road scheme in the midland region of Ireland. Observations on spatial vegetation dynamics and woodland resource patterns are also reported on. The data were analysed through percentage frequency and multivariate analyses. The results reveal woodland resource usage in terms of wood types selected for use as fuel or as structural wood as well as patterns of change and variability in taxonomic composition in relation to site types, feature types and time periods. Selection was found to be low in prehistoric times and in particular at burnt mound sites/fulachta fiadh but became increasingly important as time progressed. This has important implications when charcoal from archaeological settings is used in environmental reconstructions.  相似文献   
8.
A noted Hong Kong-based economist addresses the emerging financing problems prompted by debt-laden local governments in China in the aftermath of the global financial crisis. More specifically, using the most recent data available, he traces the root of China's local debt overhang to a protracted debt-financed infrastructure investment boom in which several key institutions (the cadre evaluation system, the land management regime, and the banking sector) have created an environment that draws local governments into a land-infrastructure-leverage trap. The author argues that the resulting high levels of debt may ultimately impede the country's efforts to mitigate structural imbalances in its economy. Journal of Economic Literature, Classification Numbers: H600, H700, P200, P300. 3 figures, 9 tables, 121 references.  相似文献   
9.
为做好蓬莱小海2005年新出土三艘古船的脱水保护工作,采集了2.3号船的船材、两船之间地下水、船下淤泥和近海海水样品,委托山东省分析测试中心检测了样品中主要离子的含量。检测结果表明,木材和淤泥中的主要离子含量远远高于海水和地下水中的;木材腐朽的程度愈严重,其离子量含量也愈大。测试数据和方法对今后古船脱盐和脱水工作有一定的指导意义。  相似文献   
10.
青花瓷器产地判别研究   总被引:2,自引:0,他引:2  
本项研究以江西省景德镇、云南省玉溪、建水、福建省平和的青花瓷器为主,结合香港清代碗窑以及德国、日本、泰国的现代青花瓷器,用能量色散X射线荧光(EDXRF)分析方法,在无损的情况下对其元素含量进行分析,得到了Ti、Mn、Fe、Co、Ni、Cu、Zn、Ga、Pb、Rb、Sr、Y、Zr13个元素的含量结果。用主成分分析方法对数据进行处理,利用第1主成分、第2主成分、第3主成分在三维座标系中绘制散点图,所得类群关系与已知情况完全相符。研究结果表明本文的研究方法可用于青花瓷器的产地判别。  相似文献   
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