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1.
IPv6与欧洲   总被引:1,自引:0,他引:1  
雷震洲 《世界电信》2002,15(7):6-10
在推进IPv6的问题上,亚洲表现的最为积极,这是因为亚洲各国承受着巨大的IP地址方面的压力。欧洲虽然在这方面没有这样大的压力,但在互联网方面一直落后于美国,这是欧洲所不甘心的。因此,欧洲在推进IPv6方面也做了许多工作。欧洲推进IPv6的基本策略是先移动,后固定,并实施了一系列的行动计划和项目。欧洲面临的挑战主要是已经部署了数量巨大的网元、操作系统与软件应用必须予以更新、互通或取代,需要仔细规划和大量投资。  相似文献   
2.
Michael Nones 《国际水》2017,42(3):324-332
The implementation of the EU Floods Directive by water authorities across Europe has generated a lack of consistency in the present situation, especially regarding the scales adopted, the hydrological scenarios and the elements represented on flood hazard and risk maps. From the EU-funded project HYTECH, this article presents a general overview of Floods Directive implementation in eight European countries, highlighting the differences between them, with particular attention to flood hazard maps. For the implementation cycle that started at the beginning of 2016, a minimization of such differences is necessary in order to manage flood risk in a better and more integrated way.  相似文献   
3.
殷浩澍 《电焊机》2005,35(7):1-5,64
为了在竞争中获胜,欧洲造船业必须提高生产速度和效率,同时降低成本。因此,他们投入了巨大的人力和财力来研发激光焊接并将其应用到造船生产实践中,以达到维持和重建欧洲船厂在全球高附加值船舶市场的优势地位。  相似文献   
4.
ABSTRACT

The gold work from the Western European Middle and Late Bronze Age (about 1500–700 BC) is characterized by solid ornaments and vessels. This article deals with manufacturing techniques of heavy gold jewelry by presenting a gold hoard found at Guînes, Pas-de-Calais, in Northern France, as a case study. In particular, three ornament types will be taken into consideration: (1) solid penannular neck and arm-rings, plain or with linear or geometric decoration; (2) flange-twisted ornaments that appear in different dimensions, as small as ear rings, as neck rings, up to the large size of a belt; (3) complex, composite ornaments. The technological aspects dealt with in this precious metal working context are manifold, including ingot and lost wax casting, hammering and bending of solid rods, the production of flange-twisted rods, chasing as decoration method, and finally joining techniques such as soldering, riveting and folding, and creasing.  相似文献   
5.
The term urban heat island describes the phenomenon of altered temperatures in urban areas compared to their rural hinterlands. A surface urban heat island encompasses the patterns of land surface temperatures in urban areas. The classical indicator to describe a surface urban heat island is the difference between urban and rural surface temperatures. However, several other indicators for this purpose have been suggested in the literature. In this study, we compared the eleven different indicators for quantifying surface urban heat islands that were most frequently used in recent publications on remote sensing-based urban heat island assessments. The dataset used here consists of 263 European cities with monthly mean temperatures from MODIS data products for July 2002, January 2003 and July 2003. We found that (i) the indicators individually reveal diurnal and seasonal patterns but show rather low correlations over time, and (ii) for single points in time, the different indicators show only weak correlations, although they are supposed to quantify the same phenomenon. Differentiating cities according to thermal climate zones increased the relationships between the indicators. Thus, we can identify temporal aspects and indicator selection as important factors determining the estimation of urban heat islands. We conclude that research should take into account the differences and instabilities of the indicators chosen for quantifying surface urban heat islands and should use several indicators in parallel for describing the surface urban heat island of a city.  相似文献   
6.
Orietta Pedemonte studies how mathematics in taught in faculties or schools of architecture in Belgium, Portugal, France, Switzerland and Spain, comparing course organizations, subjects offered and entrance requirements. Which and how much mathematics for architecture? What kind of teaching? Is it better to have information on many aspects, or a deeper insight into only a few? Is it better to privilege a historical-philosophical overview, or to focus aspects of application that are current today? These are some of the questions that are raised by whoever deals with teaching mathematics in a faculty or school of architecture.  相似文献   
7.
This paper analyzes the Russian software industry in the context of trade in information technology services. We assess Russia's underlying sources of competitive edge in software, such as its scientific establishments, education system, diaspora and low costs, and identify the institutional impediments to growth. A survey reveals that foreign outsourcing contracts, a high value-added niche and high education levels characterize Russia's small, privately held software firms. A comparison with the Indian software industry underscores the structural differences in outsourcing relationships developed by the two countries and emphasizes that national advantages are complex amalgamations of many factors and need to be overtly marketed. Beyond the resources that give comparative and competitive advantage to a transitioning economy, a critical role is played by powerful industry organizations and by non-market state institutions that can level the economic field and inject credibility into market structures.  相似文献   
8.
Abstract. Johannes Kepler's system of mathematical archetypes played a primary role in his physical cosmology. Identified as the geometrical models making up the metaphysical blueprint of the material world, Kepler's archetypes underlay every aspect of his world picture. Despite their importance, however, it has remained unclear how Kepler conceived of the archetypes in corporeal terms, that is, how he saw archetypes as being embodied in the form of material phenomena. Kepler's solution, I suggest, is an efficient cause, a facultas animalis, or animate faculty, pervading both the celestial and the terrestrial realms. In addition to its ability to realise the archetypes in their physical form, the animate faculty allowed Kepler to account for heavenly and earthly occurrences in terms of the same geometrical principles. Faraway phenomena such as comets and new stars could thus be seen as essentially comparable to more accessible curiosities on the Earth.  相似文献   
9.
近年来欧美关系的变化成为国际政治领域最值得关注的问题之一。欧美关系的新变化将深刻影响未来国际格局的形成。欧洲一体化是集经济一体化、政治一体化、社会规范化、文化均质化于一身的综合性进程,随着一体化的深入发展与冷战的结束,欧盟已成为欧洲地区重要的政治力量,欧美关系也逐渐发生变化。自身力量的增强使得欧盟谋求更大的政治影响,试图建立与美国的平等地位。目前,欧洲正日益成为一种平衡美国单极霸权的力量。欧美关系成为影响世界格局的重要变量。  相似文献   
10.
The liberalization of television markets and the emergence of commercial channels has changed the position of public television, bringing an end to monopolies. Public television now competes for audiences with private television. In this paper, the authors analyze the changes to the market position of public television in Germany, Spain, France, the United Kingdom (UK), and Italy between 1995 and 2019. In this 25-year period, all of these countries have had a liberalized TV market. The aim of this paper is to demonstrate the ways in which public television competes with commercial television, assessing the consequences of this on market power. This analysis allows us to detect similarities and dissimilarities between public television and television markets in large Western European countries. The results show the decline of the market share of public television in all countries, except Germany. Furthermore, public television has remained market leading in all countries, with the exception of Spain. One of the ways to compete with commercial television is to start new public channels and acquire a large audience.  相似文献   
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