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991.
针对传统的图像仿射配准(Affine image alignment, AIA)算法无法有效兼顾算法效率和鲁棒性的问题, 提出了一种快速鲁棒的新仿射配准算法---主动漂移矫正(Active drift correction, ADC)算法用于跟踪视频运动目标. 该算法的基本思想是: 通过引入一个漂移矫正项, 来改进传统算法的目标能量函数, 使算法具备抗漂移的能力, 从而提高算法的鲁棒性. 改进后的算法不需要传统算法中为增强鲁棒性而采用的许多复杂措施(如: 被动漂移矫正). 实验结果表明: 本文提出的算法简单、有效, 在不必牺牲算法效率和复杂度的条件下, 可以获得比传统算法更好的鲁棒性. 相似文献
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993.
We present the PHATT algorithm for plan recognition. Unlike previous approaches to plan recognition, PHATT is based on a model of plan execution. We show that this clarifies several difficult issues in plan recognition including the execution of multiple interleaved root goals, partially ordered plans, and failing to observe actions. We present the PHATT algorithm's theoretical basis, and an implementation based on tree structures. We also investigate the algorithm's complexity, both analytically and empirically. Finally, we present PHATT's integrated constraint reasoning for parametrized actions and temporal constraints. 相似文献
994.
This work addresses the problem of offset-free Model Predictive Control (MPC) when tracking an asymptotically constant reference. In the first part, compact and intuitive conditions for offset-free MPC control are introduced by using the arguments of the internal model principle. In the second part, we study the case where the number of measured variables is larger than the number of tracked variables. The plant model is augmented only by as many states as there are tracked variables, and an algorithm which guarantees offset-free tracking is presented. In the last part, offset-free tracking properties for special implementations of MPC schemes are briefly discussed. 相似文献
995.
To achieve size preserving tracking, in addition to controlling the camera’s pan and tilt motions to keep the object of interest
in the camera’s field of view (FOV), the camera’s focal length is adjusted automatically to compensate for the changes in
the target’s image size caused by the relative motion between the camera and the target. The estimation accuracy of these
changes determines the effectiveness of the resulting zoom control. The existing method of choice for real-time target scale
estimation applies structure from motion (SFM) based on the weak perspective projection model. In this paper we propose a
target scale estimation algorithm with a linear solution based on the more advanced paraperspective projection model, which
improves the accuracy of scale estimation by considering center offset. Another key issue in SFM based algorithms is the separation
of target and background features, especially when composite camera (pan/tilt/zoom) and target motions are involved. This
paper designs a fast target feature separation/grouping algorithm, the 3D affine shape method. The resulting separation automatically
adapts to the target’s 3D geometry and motion and is able to accommodate a large amount of off-plane rotation, which most
existing separation/grouping algorithms find difficult to achieve. Experimental results illustrate the effectiveness of the
proposed scale estimation and feature separation algorithms in tracking translating and rotating objects with a PTZ camera
while preserving their sizes. In comparison with the leading size preserving tracking algorithm described by Tordoff and Murray,
our algorithm is able to reduce the cumulative tracking error significantly from 17.4% to 3.3%. 相似文献
996.
Mahdi Aliyari Shoorehdeli Mohammad Teshnehlab Ali Khaki Sedigh 《Neural computing & applications》2009,18(2):157-174
This paper suggests novel hybrid learning algorithm with stable learning laws for adaptive network based fuzzy inference system
(ANFIS) as a system identifier and studies the stability of this algorithm. The new hybrid learning algorithm is based on
particle swarm optimization (PSO) for training the antecedent part and gradient descent (GD) for training the conclusion part.
Lyapunov stability theory is used to study the stability of the proposed algorithm. This paper, studies the stability of PSO
as an optimizer in training the identifier, for the first time. Stable learning algorithms for the antecedent and consequent
parts of fuzzy rules are proposed. Some constraints are obtained and simulation results are given to validate the results.
It is shown that instability will not occur for the leaning rate and PSO factors in the presence of constraints. The learning
rate can be calculated on-line and will provide an adaptive learning rate for the ANFIS structure. This new learning scheme
employs adaptive learning rate that is determined by input–output data. 相似文献
997.
This paper reports a work that was intended to reveal the connection between topics investigated by conference papers and journal papers. This work selected hundreds of papers in data mining and information retrieval from well-known databases and showed that the topics covered by conference papers in a year often leads to similar topics covered by journal papers in the subsequent year and vice versa. This study used some existing algorithms and combination of these algorithms to proposed a new detective procedure for the researchers to detect the new trend and get the academic intelligence from conferences and journals.The goal of this research is fourfold: First, the research investigates if the conference papers’ themes lead the journal papers’. Second, the research examines how the new research themes can be identified from the conference papers. Third, the research looks at a specific area such as information retrieval and data mining as an illustration. Fourth, the research studies any inconsistencies of the correlation between the conference papers and the journal papers.This study explores the connections between the academic publications. The methodologies of information retrieval and data mining can be exploited to discover the relationships between published papers among all topics. By discovering the connections between conference papers and journal papers, researchers can improve the effectiveness of their research by identifying academic intelligence.This study discusses how conference papers and journal papers are related. The topics of conference papers are identified to determine whether they represent new trend discussed in journal papers. An automatic examination procedure based on information retrieval and data mining is also proposed to minimize the time and human resources required to predict further research developments. This study develops a new procedure and collects a dataset to verify those problems. Analytical results demonstrate that the conference papers submitted to journals papers are similar each year. Conference papers certainly affect the journal papers published over three years. About 87.23% of data points from papers published in 1991–2007 support our assumption. The research is intended to help researchers identify new trend in their research fields, and focus on the urgent topics. This is particularly valuable for new researchers in their field, or those who wish to perform cross-domain studies. 相似文献
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