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21.
Giorgio Guglieri Valeria Mariano Fulvia Quagliotti Alessandro Scola 《Journal of Intelligent and Robotic Systems》2011,61(1-4):399-421
The Italian SMAT project is a civilian program supported by Piemonte Region developed for the territorial monitoring and surveillance and for the prevention of natural hazards. In a different way from the previous surveillance programs, the SMAT project is based on the use of several unmanned platforms that are able to cooperate through ground coordination and control station. The flight in non-segregated airspace, needed in order to accomplish the territorial monitoring mission, is a main issue to be investigated and defined, because of the current lack of a common consensus and agreement on the regulations of UAS. The present work outlines the international initiatives that deal with the development of the regulatory framework on airworthiness and certification of UAS and their potential impact on the SMAT project. 相似文献
22.
Social signal processing: Survey of an emerging domain 总被引:3,自引:1,他引:2
The ability to understand and manage social signals of a person we are communicating with is the core of social intelligence. Social intelligence is a facet of human intelligence that has been argued to be indispensable and perhaps the most important for success in life. This paper argues that next-generation computing needs to include the essence of social intelligence – the ability to recognize human social signals and social behaviours like turn taking, politeness, and disagreement – in order to become more effective and more efficient. Although each one of us understands the importance of social signals in everyday life situations, and in spite of recent advances in machine analysis of relevant behavioural cues like blinks, smiles, crossed arms, laughter, and similar, design and development of automated systems for social signal processing (SSP) are rather difficult. This paper surveys the past efforts in solving these problems by a computer, it summarizes the relevant findings in social psychology, and it proposes a set of recommendations for enabling the development of the next generation of socially aware computing. 相似文献
23.
24.
Alessandro Agnetis Enrico Grande Pitu B. Mirchandani Andrea Pacifici 《Computers & Operations Research》2009
The paper addresses the problem of locating sensors with a circular field of view so that a given line segment is under full surveillance, which is termed as the disc covering problem on a line. The cost of each sensor includes a fixed component f, and a variable component that is a convex function of the diameter of the field-of-view area. When only one type of sensor or, in general, one type of disc, is available, then a simple polynomial algorithm solves the problem. When there are different types of sensors, the problem becomes hard. A branch-and-bound algorithm as well as an efficient heuristic are developed for the special case in which the variable cost component of each sensor is proportional to the square of the measure of the field-of-view area. The heuristic very often obtains the optimal solution as shown in extensive computational testing. 相似文献
25.
Alfonso E. Gerevini Patrik Haslum Derek Long Alessandro Saetti Yannis Dimopoulos 《Artificial Intelligence》2009,173(5-6):619-668
The international planning competition (IPC) is an important driver for planning research. The general goals of the IPC include pushing the state of the art in planning technology by posing new scientific challenges, encouraging direct comparison of planning systems and techniques, developing and improving a common planning domain definition language, and designing new planning domains and problems for the research community. This paper focuses on the deterministic part of the fifth international planning competition (IPC5), presenting the language and benchmark domains that we developed for the competition, as well as a detailed experimental evaluation of the deterministic planners that entered IPC5, which helps to understand the state of the art in the field.We present an extension of pddl, called pddl3, allowing the user to express strong and soft constraints about the structure of the desired plans, as well as strong and soft problem goals. We discuss the expressive power of the new language focusing on the restricted version that was used in IPC5, for which we give some basic results about its compilability into pddl2. Moreover, we study the relative performance of the IPC5 planners in terms of solved problems, CPU time, and plan quality; we analyse their behaviour with respect to the winners of the previous competition; and we evaluate them in terms of their capability of dealing with soft goals and constraints, and of finding good quality plans in general. Overall, the results indicate significant progress in the field, but they also reveal that some important issues remain open and require further research, such as dealing with strong constraints and computing high quality plans in metric-time domains and domains involving soft goals or constraints. 相似文献
26.
This note deals with the implementation of a second-order sliding mode control algorithm for a class of nonlinear systems in which the sign of the high-frequency gain, though constant, is unknown. A specific second-order sliding mode control algorithm, the “Suboptimal” algorithm, is properly modified in order to face the uncertainty in the control direction. It is shown that after a finite time the uncertain sign is identified and the standard finite time convergence takes place from that time on. Simulation results are provided. 相似文献
27.
Alessandro Pollini 《AI & Society》2009,24(2):165-171
In interacting with artificial social agents, novel forms of sociality between humans and machines emerge. The theme of Social
Agency between humans and robots is of emerging importance. In this paper key theoretical issues are discussed in a preliminary
exploration of the concept. We try to understand what Social Agency is and how it is created by, negotiated with, and attributed
to artificial agents. This is done in particular considering socially situated robots and by exploring how people recognize
and accept social agents. The interplay between humans and agents is investigated through dynamics of interpretation, signification
and attribution. The ultimate goal of this research is to explore the challenges and opportunities brought by the design of
socially intelligent agents.
相似文献
Alessandro PolliniEmail: |
28.
This paper proposes a novel class of Command Governor (CG) strategies for input and state-related constrained discrete-time LTI systems subject to bounded disturbances in the absence of explicit state or output measurements. While in traditional CG schemes the set-point manipulation is undertaken on the basis of either the actual measure of the state or its suitable estimation, it is shown here that the CG design problem can be solved, with limited performance degradation and with similar properties, also in the case that such an explicit measure is not available. This approach, which will be referred to as the Feed-Forward CG (FF-CG) approach, may be a convenient alternative CG solution in all situations whereby the cost of measuring the state may be a severe limitation, e.g. in distributed or decentralized applications. In order to evaluate the method proposed here, numerical simulations on a physical example have been undertaken and comparisons with the standard state-based CG solution reported. 相似文献
29.
Damien Sulla-Menashe Mark A. Friedl Olga N. Krankina Alessandro Baccini Curtis E. Woodcock Adam Sibley Guoqing Sun Viacheslav Kharuk Vladimir Elsakov 《Remote sensing of environment》2011,115(2):392-403
The Northern Eurasian land mass encompasses a diverse array of land cover types including tundra, boreal forest, wetlands, semi-arid steppe, and agricultural land use. Despite the well-established importance of Northern Eurasia in the global carbon and climate system, the distribution and properties of land cover in this region are not well characterized. To address this knowledge and data gap, a hierarchical mapping approach was developed that encompasses the study area for the Northern Eurasia Earth System Partnership Initiative (NEESPI). The Northern Eurasia Land Cover (NELC) database developed in this study follows the FAO-Land Cover Classification System and provides nested groupings of land cover characteristics, with separate layers for land use, wetlands, and tundra. The database implementation is substantially different from other large-scale land cover datasets that provide maps based on a single set of discrete classes. By providing a database consisting of nested maps and complementary layers, the NELC database provides a flexible framework that allows users to tailor maps to suit their needs. The methods used to create the database combine empirically derived climate–vegetation relationships with results from supervised classifications based on Moderate Resolution Imaging Spectroradiometer (MODIS) data. The hierarchical approach provides an effective framework for integrating climate–vegetation relationships with remote sensing-based classifications, and also allows sources of error to be characterized and attributed to specific levels in the hierarchy. The cross-validated accuracy was 73% for the land cover map and 73% and 91% for the agriculture and wetland classifications, respectively. These results support the use of hierarchical classification and climate–vegetation relationships for mapping land cover at continental scales. 相似文献
30.
Enver Sangineto Nicola Capuano Matteo Gaeta Alessandro Micarelli 《Universal Access in the Information Society》2008,7(1-2):1-23
This paper presents an approach to automatic course generation and student modeling. The method has been developed during
the European funded projects Diogene and Intraserv, focused on the construction of an adaptive e-learning platform. The aim
of the platform is the automatic generation and personalization of courses, taking into account pedagogical knowledge on the
didactic domain as well as statistic information on both the student’s knowledge degree and learning preferences. Pedagogical
information is described by means of an innovative methodology suitable for effective and efficient course generation and
personalization. Moreover, statistic information can be collected and exploited by the system in order to better describe
the student’s preferences and learning performances. Learning material is chosen by the system matching the student’s learning
preferences with the learning material type, following a pedagogical approach suggested by Felder and Silverman. The paper
discusses how automatic learning material personalization makes it possible to facilitate distance learning access to both
able-bodied and disabled people. Results from the Diogene and Intraserv evaluation are reported and discussed. 相似文献