全文获取类型
收费全文 | 632篇 |
免费 | 42篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 177篇 |
金属工艺 | 7篇 |
机械仪表 | 11篇 |
建筑科学 | 11篇 |
矿业工程 | 1篇 |
能源动力 | 14篇 |
轻工业 | 46篇 |
水利工程 | 15篇 |
无线电 | 62篇 |
一般工业技术 | 105篇 |
冶金工业 | 141篇 |
原子能技术 | 10篇 |
自动化技术 | 70篇 |
出版年
2022年 | 11篇 |
2021年 | 27篇 |
2020年 | 14篇 |
2019年 | 26篇 |
2018年 | 22篇 |
2017年 | 12篇 |
2016年 | 17篇 |
2015年 | 16篇 |
2014年 | 27篇 |
2013年 | 31篇 |
2012年 | 37篇 |
2011年 | 27篇 |
2010年 | 17篇 |
2009年 | 20篇 |
2008年 | 22篇 |
2007年 | 27篇 |
2006年 | 13篇 |
2005年 | 14篇 |
2004年 | 17篇 |
2003年 | 15篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 39篇 |
1997年 | 24篇 |
1996年 | 25篇 |
1995年 | 18篇 |
1994年 | 12篇 |
1993年 | 14篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1983年 | 9篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1973年 | 4篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有674条查询结果,搜索用时 15 毫秒
31.
Simos Gerasimou Radu Calinescu Giordano Tamburrelli 《Automated Software Engineering》2018,25(4):785-831
An increasingly used method for the engineering of software systems with strict quality-of-service (QoS) requirements involves the synthesis and verification of probabilistic models for many alternative architectures and instantiations of system parameters. Using manual trial-and-error or simple heuristics for this task often produces suboptimal models, while the exhaustive synthesis of all possible models is typically intractable. The EvoChecker search-based software engineering approach presented in our paper addresses these limitations by employing evolutionary algorithms to automate the model synthesis process and to significantly improve its outcome. EvoChecker can be used to synthesise the Pareto-optimal set of probabilistic models associated with the QoS requirements of a system under design, and to support the selection of a suitable system architecture and configuration. EvoChecker can also be used at runtime, to drive the efficient reconfiguration of a self-adaptive software system. We evaluate EvoChecker on several variants of three systems from different application domains, and show its effectiveness and applicability. 相似文献
32.
Geoff Giordano 《Plastics Engineering》2019,75(1):28-35
The global push toward finalizing and implementing the next generation of connected smart machinery—the Industry 4.0 protocols—begs the question: how will these new standards influence equipment purchasing decisions for plastics manufacturers? 相似文献
33.
ABSTRACT Concern over increasing water scarcity has led to the introduction of the concept of agricultural water productivity and an emphasis on interventions to achieve ‘more crop per drop’. Yet, a strong debate continues on how the concept is to be defined and used. Drawing largely from the irrigation literature, the origins of the concept and its methodological developments are reviewed, and its use in applied work over two decades is discussed. Based on this analysis of conceptual and applied research, key insights into the concept’s contributions and limitations are presented, as well as opportunities for further refinements. 相似文献
34.
Water Resources Management - The provision of critical services, such as drinking water, is crucial both in ordinary and in emergency conditions due to either natural (e.g. earthquakes, droughts,... 相似文献
35.
36.
37.
38.
Thierry Giordano 《Planning Theory & Practice》2013,14(4):480-504
The South African government has named the transition towards a greener economy one of its priorities. Meanwhile it has developed a new multilevel integrated planning process, and announced a massive public infrastructure investment plan. The converging point of these three dynamics should be the integration of green infrastructure principles into the different plans as the foundation of the green transition. This paper uses a policy integration analytical framework to assess whether this convergence is in fact taking shape. It analyses the level of integration of green infrastructure principles into the different plans and suggests options to move the green infrastructure agenda forward. 相似文献
39.
Cristina Cornaro Simona Bartocci Davide Musella Cecilia Strati Alessandro Lanuti Simone Mastroianni Stefano Penna Andrea Guidobaldi Fabrizio Giordano Eleonora Petrolati Thomas M. Brown Andrea Reale Aldo Di Carlo 《Progress in Photovoltaics: Research and Applications》2015,23(2):215-225
New generation photovoltaic (PV) devices such as polymer and dye sensitized solar cells (DSC) have now reached a more mature stage of development, and among their various applications, building integrated PVs seems to have the most promising future, especially for DSC devices. This new generation technology has attracted an increasing interest because of its low cost due to the use of cheap printable materials and simple manufacturing techniques, easy production, and relatively high efficiency. As for the more consolidated PV technologies, DSCs need to be tested in real operating conditions and their performance compared with other PV technologies to put into evidence the real potential. This work presents the results of a 3 months outdoor monitoring activity performed on a DSC mini‐panel made by the Dyepower Consortium, positioned on a south oriented vertical plane together with a double junction amorphous silicon (a‐Si) device and a multi‐crystalline silicon (m‐Si) device at the ESTER station of the University of Rome Tor Vergata. Good performance of the DSC mini‐panel has been observed for this particular configuration, where the DSC energy production compares favorably with that of a‐Si and m‐Si especially at high solar angles of incidence confirming the suitability of this technology for the integration into building facades. This assumption is confirmed by the energy produced per nominal watt‐peak for the duration of the measurement campaign by the DSC that is 12% higher than that by a‐Si and only 3% lower than that by m‐Si for these operating conditions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
40.
Danuta Kuzmicz Paul Coupillaud Yongjun Men Joan Vignolle Giordano Vendraminetto Martina Ambrogi Daniel Taton Jiayin Yuan 《Polymer》2014
Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m2/g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, benzoin condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO2 activation. 相似文献