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91.
我国古代先民很早就意识到琥珀的装饰和药用价值,汉代开始从西域引入琥珀,唐代时琥珀已比较常见。我国古代琥珀多为进口琥珀,琥珀产地分析可以反映中外文化交流情况。国内仅对私人琥珀藏品进行过分析,考古出土琥珀的科技分析尚未见报道。本研究通过红外光谱分析,判定成都光华村街低阶官员唐墓出土红色饰品为琥珀;再与若干产地的琥珀开展红外光谱对比,鉴定其产地为波罗的海地区。琥珀经过丝绸之路到达蜀地并为低阶官员所使用,足见唐代琥珀制品的盛行及当时国际贸易文化交流的盛况。  相似文献   
92.
年画是中国特有的民间艺术形式。本研究介绍了传统年画印制所用红蓝色料的发展历史,选取15种中国古代与近现代常用红蓝色料进行红外光谱分析,并归纳总结了标准样品的化学结构与红外谱图特征。在此基础上,利用衰减全反射傅里叶变换红外光谱仪对三幅清末民初时期的传统年画开展无损检测。结果显示三幅年画的红蓝色料均为合成颜料或染料,包括酸性大红G、酸性墨水蓝G、普鲁士蓝等。本研究扩展了红外光谱在书画文物分析检测中的应用范围,为传统年画色料的无损鉴定提供科学依据。  相似文献   
93.
ABSTRACT

Historic heritage buildings are a part of historic basis of each society and an economic resource. Therefore, preserving and maintenance of these buildings are cultural, economic and social demand. This research investigates the seismic performance of a historical building named Arg of Tabriz (Arge Alishah) that dates back to 14th century and is located at the city center of Tabriz (NW of Iran). Static, modal, and finally nonlinear dynamic (time history) analysis were performed by both “Considering Soil-Structure Interaction (SSI)” and “fixed base (ignoring SSI)” Cases.

It is found from the results that, SSI extremely affects mode shapes and their frequencies and depending on the frequency content of the records, can has an incremental or decremental effect on structural responses. As expected, the building of Arg could carry gravity loads easily and despite its stability against earthquake loading in fixed base case, showed a weakness (especially in eastern and western walls direction) and overturned when it was analyzed in SSI case because of yielding of the surrounding soil.  相似文献   
94.
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   
95.
ABSTRACT

The interpretative power of quantitative intra-site spatial analysis has long been recognised by archaeologists. On the contrary, very few ethnoarchaeological works have engaged with the statistical analysis of intra-site pattern of artefacts and ecofacts. Nonetheless, ethnoarchaeology is uniquely placed to guide and assist in the identification of sound techniques and in the development of the methodology of analysis. The possibility to directly connect the distribution of the proxies under study with the activity that generated such distribution, provide the means of fine-tuning the tools we use for identifying these patterns in the archaeological record. As a consequence, archaeological methodology and interpretation both benefit from the application of improved methodologies. In this paper we review some of the most common techniques used to analyse activity areas and we provide examples of the application of such techniques to ethnoarchaeological contexts. The aim is to assess how archaeology can benefit from the intra-site spatial analysis of ethnoarchaeological contexts.  相似文献   
96.
ABSTRACT

Transylvania has not only a geographical location as a province of Romania but also a mental meaning as Dracula's land. Dracula has become an important brand name for Romania, attracting many tourists in recent years – especially after the fall of communism. The main dimensions of Dracula's castle (i.e. Bran Castle) experiences shared online by tourists were identified to ascertain the primary reasons for satisfaction and dissatisfaction with visits and to test whether narratives and satisfaction vary according to the occasion (i.e. Halloween). Quantitative (i.e. computer-based) and qualitative (i.e. narrative) content analyses were conducted on the Web reviews written by visitors. The results reveal that the experiences are multidimensional, and they include the following themes: ‘castle’, ‘visit’, ‘Dracula’, ‘inside’, ‘tourist’, ‘outside’, ‘trip’, ‘souvenirs’, ‘stairs’ and ‘Dracula's castle’. The main reasons for dissatisfaction are overcrowding, which is connected with the outside theme, and the disappointment of tourists regarding the old furniture, which is associated with the inside theme. The results also reveal that visitors are the most satisfied with their experience around the time of Halloween. The narratives shared online emphasise tourists’ need to associate their imaginings with this region and castle, giving their experiences greater meaning through this destination's image as Transylvania.  相似文献   
97.
Europe 2020 is a 10-year EU strategy, promoting smart, sustainable and inclusive growth. Despite ambitious goals, its spatially blinded approach might seriously threaten its success. Actually, large territorial disparities still affect the EU, being the basis for a strong EU-wide cohesion policy and suggesting a general re-framing of sectoral policies on a regional basis. In this respect, the paper tackles the issue of regional disparities in achieving Europe 2020 Strategy targets. As the Strategy involves different targets, principal component analysis is applied to disentangle Europe 2020 domains and to describe major differences in EU-27 NUTS 2 regional performances. In particular, two components are returned: high-employment inclusive growth and smart growth. Territorial patterns of both components are analysed, by jointly considering some geographical features that may affect them. Both a rural and a spatial effect occur: rural and remote regions show poor performances whilst the presence of spatial autocorrelation may actually lock-in negative outcomes. When considering urban rural divides, also within-regions disparities matter. Results strengthen the idea that Europe 2020, as other sectoral policies, should be translated into a regional setting according to a place-based approach: although requiring large efforts, this represents the only way to fully achieve its own targets.  相似文献   
98.
The article contributes to the smart specialization literature by presenting a new approach, connectivity analysis, where Triple Helix (TH) relations (involving universities, companies and government) are at the centre of the entrepreneurial discovery process. Relations between helices may be seen, from the point of departure of proximity, as preconditions of connectivity, or interaction, measured through expectations and experiences. This offers potential solution to two limitations of proximity approach: its static nature and narrow focus on dyadic relationships. The connectivity analysis reveals the extent of mutual expectations, as well as tensions, or gaps. Based on this analysis, the article presents a policy model that is used to map structures of networks and gaps between TH actors. It may also identify strengths, weaknesses and problems. This analysis is used as input to structured dialogues between actors in leading positions in the TH and in smart specialization policy-making and implementation. This approach may lead to policy interventions supporting entrepreneurial discoveries. The model has been developed in partnership with researchers and the Regional Council of Ostrobothnia. The article also presents this case study and demonstrates the use of the connectivity model in practice.  相似文献   
99.
Knowledge about human subsistence and the role of animal economy in the Islamic period of south‐east Arabia is still sketchy. The analysis of faunal remains from the coastal fort at Luluyyah (Sharjah, UAE), dated to the late thirteenth and early fourteenth century CE, provides some information. People depended on marine resources and domestic animals, a trait observable in the region since the Neolithic. Livestock breeding was not particularly developed. Judging by the distribution of their skeletal remains, the animals were slaughtered at the fort, implying that they either lived there or reached it alive.  相似文献   
100.
目前对文物保护的研究主要以试验为主,本研究试图用数值方法分析文物展柜的动力学特性,以解决试验分析方法所导致的缺陷。为此,对固定和浮放两种不同边界条件的文物展柜进行地震作用和简谐激励下的动力响应分析,给出了展柜展台面处的加速度动力放大系数(简称放大系数)上限值。以某博物馆展柜为原型,按1∶1/0.39进行缩尺振动试验,得出两种边界条件下展柜展台面处的放大系数。对试验展柜建立有限元模型,通过与试验对比,验证模型及分析方法的正确性。然后,建立展柜模型的有限元模型,对5种尺寸的展柜进行了动力响应分析,并考虑激励幅值、激励频率等对放大系数的影响。分析结果有助于指导文物的防震保护工作。  相似文献   
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