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81.
Pedro Casas Lionel Fillatre Sandrine Vaton Igor Nikiforov 《Journal of Network and Systems Management》2011,19(1):58-83
This paper presents a novel approach to deal with dynamic and highly uncertain traffic in dynamic network scenarios. The Reactive
Robust Routing (RRR) approach is introduced, a combination of proactive and reactive techniques to improve network efficiency
and robustness, simplifying network operation. RRR optimizes routing for normal-operation traffic, using a time-varying extension
of the already established Robust Routing technique that outperforms the stable approach. To deal with anomalous and unexpected
traffic variations, RRR uses a fast anomaly detection and localization algorithm that rapidly detects and localizes abrupt
changes in traffic flows, permitting an accurate routing adaptation. This algorithm presents well-established optimality properties
in terms of detection/localization rates and localization delay, which allows for generalization of results, independently
of particular evaluations. The algorithm is based on a novel parsimonious model for traffic demands which allows for detection
of anomalies using easily available aggregated-traffic measurements, reducing the overheads of data collection. 相似文献
82.
The 24-H Knowledge Factory facilitates collaboration between geographically and temporally distributed teams. The teams themselves
form a strategic partnership whose joint efforts contribute to the completion of a project. Project-related tasks are likewise
distributed, allowing tasks to be completed on a continuous basis, regardless of the constraints of any one team’s working
hours. However, distributing a single task between multiple teams necessitates a handoff process, where one team’s development
efforts and task planning are communicated from one team ending their shift to the next that will continue the effort. Data
management is, therefore, critical to the success of this business model. Efficiency in data management is achieved through
a strategic leveraging of key tools, models, and concepts. 相似文献
83.
Explanation and reliability of prediction models: the case of breast cancer recurrence 总被引:1,自引:1,他引:0
Erik ?trumbelj Zoran Bosni? Igor Kononenko Branko Zakotnik Cvetka Gra?i? Kuhar 《Knowledge and Information Systems》2010,24(2):305-324
In this paper, we describe the first practical application of two methods, which bridge the gap between the non-expert user
and machine learning models. The first is a method for explaining classifiers’ predictions, which provides the user with additional
information about the decision-making process of a classifier. The second is a reliability estimation methodology for regression
predictions, which helps the users to decide to what extent to trust a particular prediction. Both methods are successfully
applied to a novel breast cancer recurrence prediction data set and the results are evaluated by expert oncologists. 相似文献
84.
85.
In this paper a new approach to the control of a nonlinear, time-varying process is proposed. It is based on a recursive version of the fuzzy identification method and predictive functional control. First, the recursive fuzzy identification method is derived, after which it is used in connection with fuzzy predictive functional control to construct an adaptive fuzzy predictive functional controller. The adaptive FPFC is then tested on a nonlinear, time-varying, semi-batch reactor process and compared with the standard FPFC, which uses non-adaptive fuzzy model. The simulation results are promising; they indicate that the control of time-varying, nonlinear processes with the FPFC can be improved with the use of an adaptive fuzzy model. An improvement in reference tracking and disturbance rejection can be observed, but the main advantage is the reduced number of switchings between hot and cold water. This is an important improvement in the case of real applications. 相似文献
86.
Karol MalechaAuthor Vitae Dorota G. PijanowskaAuthor VitaeLeszek J. GolonkaAuthor Vitae Piotr KurekAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):923-929
This article presents design, fabrication and testing of a miniature ceramic-based biosensor which is destined for continuous glucose monitoring. It is fabricated using well known LTCC (low temperature co-fired ceramics) technology. The biosensor consists of a microreaction chamber, three thick-film electrodes and a microdialysis tube. The detection process is based on oxidation of glucose by molecular oxygen in the presence of enzyme - glucose oxidase, GOx. One of the reaction products is a hydrogen peroxide which is detected amperometrically during its oxidation at a working electrode. Computational fluid dynamics (CFD) analysis was used for optimization of the biosensor geometry and considerations of the influence of operating conditions (flow rate) on mass transfer (diffusion) of the glucose within the microreaction chamber. Tests of the developed LTCC-based biosensor indicate its linear response to glucose concentration up to 9 mM with a relatively high sensitivity of about 147 nA/mM. Moreover, the properties of the presented ceramic biosensor are compared with properties of a similar device made in silicon/glass and in Perspex®. 相似文献
87.
Ab initio predictions of secondary structures in proteins have to combine local predictions, based on short fragments of the
protein sequence, with consistency restrictions, as not all locally plausible predictions may be simultaneously true.
We use the fact that secondary structures are patterns of hydrogen bonds and that a single residue can participate in hydrogen
bonds of at most one secondary structure. Consistency of fixed-sized pieces of secondary structures is the easiest to approximate
and we formalize it as 1-2 matching problem. Consistency of entire secondary structures is a version of set packing. We also
investigate how to form a simple problem if we add the requirement that the secondary structure and the loops that connect
them fit together in a metric space.
Every problem that we investigated is MAX-SNP hard and it has a constant factor approximation. Computational experience suggests
that in biological instances, we can find nearly optimal solutions using heuristics. 相似文献
88.
The paper provides comparison of three different approaches to on-line tuning of generalized adaptive notch filters (GANFs) — the algorithms used for identification/tracking of quasi-periodically varying dynamic systems. Tuning is needed to adjust adaptation gains, which control tracking performance of GANF algorithms, to the unknown and/or time time-varying rate of system nonstationarity. Two out of three compared approaches are classical solutions — the first one incorporates sequential optimization of adaptation gains while the second one is based on the concept of parallel estimation. The main contribution of the paper is that it suggests the third way — it shows that the best results can be achieved when both approaches mentioned above are combined in a judicious way. Such joint sequential/parallel optimization preserves advantages of both treatments: adaptiveness (sequential approach) and robustness to abrupt changes (parallel approach). Additionally the paper shows how, using the concept of surrogate outputs, one can extend the proposed single-frequency algorithm to the multiple frequencies case, without falling into the complexity trap known as the “curse of dimensionality”. 相似文献
89.
Oscillations and transfer properties of relay feedback systems with time-delay linear plants 总被引:1,自引:0,他引:1
Igor Boiko Author vitae 《Automatica》2009,45(12):2897-2902
Oscillations and transfer properties of relay feedback systems with linear plants having a dead time (time delay) are considered. Poincare maps are found explicitly in terms of the system parameters. The oscillatory and transfer properties are presented in the format of the locus of a perturbed relay system (LPRS), which represents the continuum of all possible periodic solutions and transfer properties of the system with a given linear plant. Conditions of local orbital asymptotic stability are found in terms of the system parameters. The proposed approach is illustrated by examples. 相似文献
90.
Marc Baboulin Alfredo Buttari Jack Dongarra Jakub Kurzak Julie Langou Julien Langou Piotr Luszczek Stanimire Tomov 《Computer Physics Communications》2009,180(12):2526-2533
On modern architectures, the performance of 32-bit operations is often at least twice as fast as the performance of 64-bit operations. By using a combination of 32-bit and 64-bit floating point arithmetic, the performance of many dense and sparse linear algebra algorithms can be significantly enhanced while maintaining the 64-bit accuracy of the resulting solution. The approach presented here can apply not only to conventional processors but also to other technologies such as Field Programmable Gate Arrays (FPGA), Graphical Processing Units (GPU), and the STI Cell BE processor. Results on modern processor architectures and the STI Cell BE are presented.