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961.
Infonorma is a multi-agent system that provides its users with recommendations of legal normative instruments they might be
interested in. The Filter agent of Infonorma classifies normative instruments represented as Semantic Web documents into legal
branches and performs content-based similarity analysis. This agent, as well as the entire Infonorma system, was modeled under
the guidelines of MAAEM, a software development methodology for multi-agent application engineering. This article describes
the Infonorma requirements specification, the architectural design solution for those requirements, the detailed design of
the Filter agent and the implementation model of Infonorma, according to the guidelines of the MAAEM methodology. 相似文献
962.
A. Z. Kouzani 《Machine Vision and Applications》2008,19(4):223-248
There has been an increasing interest in face recognition in recent years. Many recognition methods have been developed so
far, some very encouraging. A key remaining issue is the existence of variations in the input face image. Today, methods exist
that can handle specific image variations. But we are yet to see methods that can be used more effectively in unconstrained
situations. This paper presents a method that can handle partial translation, rotation, or scale variations in the input face
image. The principal is to automatically identify objects within images using their partial self-similarities. The paper presents
two recognition methods which can be used to recognise objects within images. A face recognition system is then presented
that is insensitive to limited translation, rotation, or scale variations in the input face image. The performance of the
system is evaluated through four experiments. The results show that the system achieves higher recognition rates than those
of a number of existing approaches.
The author would like to thank the Australian Research Council (ARC) which supports this research with a Discovery Grant. 相似文献
963.
Network invariants for real-time systems 总被引:1,自引:0,他引:1
We extend the approach of model checking parameterized networks of processes by means of network invariants to the setting of real-time systems. We introduce timed transition structures (which are similar in spirit to timed automata) and define a notion of abstraction that is safe with respect to linear temporal properties. We strengthen the notion of abstraction to allow a finite system, then called
network invariant, to be an abstraction of networks of real-time systems. In general the problem of checking abstraction of real-time systems
is undecidable. Hence, we provide sufficient criteria, which can be checked automatically, to conclude that one system is
an abstraction of a concrete one. Our method is based on timed superposition and discretization of timed systems. We exemplify our approach by proving mutual exclusion of a simple protocol inspired by Fischer’s protocol,
using the model checker TLV.
Part of this work was done during O. Grinchtein’s stay at Weizmann Institute.
This author was supported by the European Research Training Network “Games”. 相似文献
964.
Yolanda Blanco-Fernndez Jos J. Pazos-Arias Alberto Gil-Solla Manuel Ramos-Cabrer Martín Lpez-Nores Jorge García-Duque Ana Fernndez-Vilas Rebeca P. Díaz-Redondo Jesús Bermejo-Muoz 《Knowledge》2008,21(4):305-320
Recommender systems arose with the goal of helping users search in overloaded information domains (like e-commerce, e-learning or Digital TV). These tools automatically select items (commercial products, educational courses, TV programs, etc.) that may be appealing to each user taking into account his/her personal preferences. The personalization strategies used to compare these preferences with the available items suffer from well-known deficiencies that reduce the quality of the recommendations. Most of the limitations arise from using syntactic matching techniques because they miss a lot of useful knowledge during the recommendation process. In this paper, we propose a personalization strategy that overcomes these drawbacks by applying inference techniques borrowed from the Semantic Web. Our approach reasons about the semantics of items and user preferences to discover complex associations between them. These semantic associations provide additional knowledge about the user preferences, and permit the recommender system to compare them with the available items in a more effective way. The proposed strategy is flexible enough to be applied in many recommender systems, regardless of their application domain. Here, we illustrate its use in AVATAR, a tool that selects appealing audiovisual programs from among the myriad available in Digital TV. 相似文献
965.
Enacting agent-based services for automated procurement 总被引:1,自引:0,他引:1
A. Giovannucci J.A. Rodríguez-Aguilar A. Reyes F.X. Noria Jesús Cerquides 《Engineering Applications of Artificial Intelligence》2008,21(2):183-199
Negotiation events in industrial procurement involving multiple, highly customisable goods pose serious challenges to buying agents when trying to determine the best set of providing agents’ offers. Typically, a buying agent's decision involves a large variety of constraints that may involve attributes of a very same item as well as attributes of different, multiple items. In this paper we present iBundler, an agent-aware service offered to buying agents to help them determine the optimal bundle of received offers based on their business rules. In this way, buying agents are relieved with the burden of solving too hard a problem and concentrate on strategic issues. iBundler is intended as a negotiation service for buying agents and as a winner determination service for reverse combinatorial auctions with side constraints. Furthermore, we assess the computational cost added by employing agent technology in the development of iBundler to characterise the type of negotiation scenarios that it can acceptably handle. 相似文献
966.
In the present paper a globally stabilizing feedback controller design method is proposed for process systems when the feedback structure is also assumed to be in a quasi-polynomial form. It is shown that such feedback structure can always be achieved for process systems.By exploiting the special structure of the controller design problem, the existent iterative linear matrix inequality (ILMI) algorithm of [Y.-Y. Cao, J. Lam, Y.-X. Sun, Static output feedback stabilization: an ILMI approach, Automatica 12 (1998) 1641–1645] is applied to solve the BMI feasibility problem underlying the design.In addition, some partial results on placing the globally stable equilibrium point with respect to the positive orthant have also been proposed that is only possible in a fully actuated situation when the input variables are the intensive variables at the inlet. Furthermore, some preliminary results in selecting the structure of the QP-type feedback have also been presented. 相似文献
967.
A steady-state interval operability methodology is introduced here for multivariable non-square systems with fewer inputs than output variables to be used in the design of model-based constrained controllers (MPC, DMC). For such systems, set-point control is not possible for all the outputs and interval control is needed. The proposed iterative approach enables the selection of the needed interval constraints systematically, so that the tightest possible control is achieved without rendering the control problem infeasible. The application of this methodology to high-dimensional industrial problems characterizing processes of Air Products and Chemicals and DuPont shows that very significant reduction of the constrained region can be achieved from the steady-state point of view. Ratios of the initial to the calculated volume of the constrained regions examined range between 104 and 108. 相似文献
968.
This paper describes a new method for increasing the computational efficiency of nonlinear robust model-based predictive control. It is based on the application of neuro-fuzzy networks and improves the computation efficiency by arranging the online optimisation to be done offline. The offline optimisation is realized by offline training a neuro-fuzzy network, consisting of zero-order T–S fuzzy rules, which is designed to approximate the input–output relationship of a robust model-based predictive controller. The design and the training of the neuro-fuzzy network are described, and the corresponding control algorithm is developed. Experiment results performed on the temperature control loop of an experimental air-handling unit (AHU) demonstrate the effectiveness of this approach. 相似文献
969.
We present a stabilizing scheduled output feedback Model Predictive Control (MPC) algorithm for constrained nonlinear systems with large operating regions. We design a set of local output feedback predictive controllers with their estimated regions of stability covering the desired operating region, and implement them as a single scheduled output feedback MPC which on-line switches between the set of local controllers and achieves nonlinear transitions with guaranteed stability. This algorithm provides a general framework for scheduled output feedback MPC design. 相似文献
970.
Business intelligence approach to supporting strategy-making of ISP service management 总被引:2,自引:0,他引:2
The recent deregulation of telecommunication industry by the Taiwanese government has brought about the acute competition for Internet Service Providers (ISP). Taiwan’s ISP industry is characterized by the heavy pressure for raising revenue after hefty capital investments of last decade and the lack of knowledge to develop competitive strategies. To attract subscribers, all ISP dealers are making an all-out effort to improve their service management. This study proposes a Business Intelligence process for ISP dealers in Taiwan to assist management in developing effective service management strategies. We explore the customers’ usage characteristics and preference knowledge through applying the attribute-oriented induction (AOI) method on IP traffic data of users. Using the self-organizing map (SOM) method, we are able to divide customers into clusters with different usage behavior patterns. We then apply RFM modeling to calibrate customers’ value of each cluster, which will enable the management to develop direct and effective marketing strategies. For network resource management, this research mines the facility utilization over various administrative districts of the region, which could assist management in planning for effective network facilities investment. With actual data from one major ISP, we develop a BI decision support system with visual presentation, which is well received by its management staff. 相似文献