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991.
Xiaonan Lu Saurabh Kataria William J. Brouwer James Z. Wang Prasenjit Mitra C. Lee Giles 《International Journal on Document Analysis and Recognition》2009,12(2):65-81
Authors use images to present a wide variety of important information in documents. For example, two-dimensional (2-D) plots
display important data in scientific publications. Often, end-users seek to extract this data and convert it into a machine-processible
form so that the data can be analyzed automatically or compared with other existing data. Existing document data extraction
tools are semi-automatic and require users to provide metadata and interactively extract the data. In this paper, we describe
a system that extracts data from documents fully automatically, completely eliminating the need for human intervention. The
system uses a supervised learning-based algorithm to classify figures in digital documents into five classes: photographs,
2-D plots, 3-D plots, diagrams, and others. Then, an integrated algorithm is used to extract numerical data from data points
and lines in the 2-D plot images along with the axes and their labels, the data symbols in the figure’s legend and their associated
labels. We demonstrate that the proposed system and its component algorithms are effective via an empirical evaluation. Our
data extraction system has the potential to be a vital component in high volume digital libraries. 相似文献
992.
As service robots and other ubiquitous technology have evolved, an increasing need for the autonomous navigation of mobile
objects has arisen. In a large number of localization schemes, the absolute-position estimation method, which relies on navigation
beacons or landmarks, has been widely used as it has the advantages of being economical and accurate. However, only a few
of these schemes have expanded their application to complicated workspaces, or those that have many rooms or blocks. As the
navigation of mobile objects in complicated workspaces is vital for ubiquitous technology, multiblock navigation is necessary.
This article presents methodologies and techniques for the multiblock navigation of the indoor localization system with active
beacon sensors. This new indoor localization system design includes ultrasonic attenuation compensation, dilution-of-precision
analysis, and a fault detection and isolation algorithm using redundant measurements.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
993.
Yau-Zen Chang Jung-Fu Hou Yung-Pyng Chang Shih-Tseng Lee 《Artificial Life and Robotics》2009,14(2):228-232
In this article, we investigate the problem of integrating a binocular stereo vision system and a laser range finder to construct
a 3-D map of the environment. The proposed scheme is realized by using the alignment parameters obtained in the 2-D map construction
of the laser range finder for the 3-D data generated by the stereo vision system. The 2-D map alignment task is formulated
as an optimization problem of minimizing the alignment errors between local maps and selected parts of the developing global
map. The problem is then solved using the Simplex method. To increase the robustness of the searching process, multiple initial
guesses are provided in the Simplex method. The performance of the proposed architecture is verified by experimental results
from a mobile vehicle for obstacle avoidance. 相似文献
994.
PID control systems are widely used in many fields, and many methods to tune the parameters of PID controllers are known.
When the characteristics of the object are changed, the traditional PID control should be adjusted by empirical knowledge.
This may result in a worse performance by the system. In this article, a new method to tune PID parameters, called the back-propagation
network modified by particle swarm optimization, is proposed. This algorithm combines conventional PID control with a back
propagation neural network (BPNN) and particle swarm optimization (PSO). This method is demonstrated in the engine idling-speed
control problem. The proposed method provides considerable performance benefits compared with a traditional controller in
this simulation. 相似文献
995.
Wonpil Yu Jae-Yeong Lee Young-Guk Ha Minsu Jang Joo-Chan Sohn Yong-Moo Kwon Hyo-Sung Ahn 《Automation Science and Engineering, IEEE Transactions on》2009,6(4):633-640
This paper describes a concerted effort to design and implement a robotic service framework. The proposed framework is comprised of three conceptual spaces: physical, semantic, and virtual spaces, collectively referred to as a ubiquitous robotic space. We implemented a prototype robotic security application in an office environment, which confirmed that the proposed framework is an efficient tool for developing a robotic service employing IT infrastructure, particularly for integrating heterogeneous technologies and robotic platforms. 相似文献
996.
In this piece we take a brief peek at the possible world of robotic companions. In such a world, robots are adopted as butlers in our homes, as baby watchers, as friends and in general as life companions. For example, Helen lives with a robotic companion named Schpuffy. In the morning, Schpuffy checks Helen's schedule and finds out she has an appointment with a neighbor to take a walk at 8:30 a.m. Schpuffy recognizes that it takes 30 minutes for her to prepare to go for a walk and wakes her up at 8:00 a.m. After she gets up, Schpuffy reminds Helen of her appointment at 8:30 a.m. While she gets dressed, Schpuffy lets her know that current weather is very cold and suggests that she wear thermal clothing. When she's about to leave the house, Schpuffy says "good bye" to her and locks the door as she leaves. Schpuffy hasn't gained majored acceptance. It's not in every home or even in a tiny fraction of homes. However, it's a bold new research that is taking shape with early commercial products already hitting the marketplace. It could soon be the chief appliance in your home, or the new interface technology for smart spaces. 相似文献
997.
Adaptive fuzzy IMM algorithm for uncertain target tracking 总被引:2,自引:0,他引:2
Hyun-Sik Kim Joon-Goo Park Dongik Lee 《International Journal of Control, Automation and Systems》2009,7(6):1001-1008
In real system application, the interacting multiple model (IMM)-based uncertain target tracking system operates with the
following problems: it requires less computing resources as well as a robust performance with respect to the maneuvering such
as a sub-model mismatched case, and further, it requires an easy design procedure related to its structures and parameters.
To solve these problems, an adaptive fuzzy IMM (AFIMM) algorithm, which is based on well-defined basis sub-models and well-adjusted
mode transition probabilities (MTPs), is proposed. The basis sub-models are defined by the detailed analysis in terms of kinematic
models as well as the maneuvering property and the MTPs are adjusted by the fuzzy adaptor as well as the fuzzy decision maker.
To verify the performance of the proposed algorithm, an airborne target tracking is performed. Simulation results show that
the AFIMM effectively solves the problems experienced in the uncertain target tracking system online. Keywords: Adaptive fuzzy
IMM, basis sub-models, mode transition probabilities, uncertain target. 相似文献
998.
Many networked human-machine interface systems have a distributed structure for certain purposes such as more computational
power, tele-presence, collaboration, and portability. However, network delays are inevitable in the distributed structure,
and often make sensory information delivered behind time to the user. In the literature, the effect of network delays on the
quality of information presentation has been considered with respect to task performances in most cases. In this paper, we
pay attention to a more stringent criterion, namely whether perceptual artifacts caused by network delays are perceptible by the user. We examined minimum perceptible
visual and/or haptic rendering delays by measuring their discrimination thresholds between normal and delayed virtual environments
with and without a task, and report the results in this paper. We also provide a simple guideline for determining whether
active delay compensation algorithms are required in a networked human-machine interface system by comparing representative
network delays to the measured discrimination thresholds.
Recommended by Guest Editor Phill Kyu Rhee. This work was supported in parts by a grant R01-2006-000-10808-0 and a NRL grant
R0A-2008-000-20087-0 both from KOSEF and by a ITRC support program C1090-0804-0002 from IITA, all funded by the Korea government.
In Lee is a Ph.D student in Computer Science and Engineering at POSTECH, of Korea. He received the B.S. degree in Information and
Communication Engineering from Sungkyunkwan University in 2006. His research interests include haptics, virtual reality, and
human-computer interaction.
Seungmoon Choi is an Assistant Professor in Computer Science and engineering at POSTECH, Korea. He received the B.S. and M.S. degrees in
Control and Instrumentation Engineering from Seoul National University in 1995 and 1997, respectively, and the Ph.D. degree
in Electrical and Computer Engineering from Purdue University in 2003. His research areas include haptics, virtual reality,
data perceptualization, and applied perception. 相似文献
999.
1000.
Daewon Lee H. Jin Kim Shankar Sastry 《International Journal of Control, Automation and Systems》2009,7(3):419-428
This paper presents two types of nonlinear controllers for an autonomous quadrotor helicopter. One type, a feedback linearization
controller involves high-order derivative terms and turns out to be quite sensitive to sensor noise as well as modeling uncertainty.
The second type involves a new approach to an adaptive sliding mode controller using input augmentation in order to account
for the underactuated property of the helicopter, sensor noise, and uncertainty without using control inputs of large magnitude.
The sliding mode controller performs very well under noisy conditions, and adaptation can effectively estimate uncertainty
such as ground effects.
Recommended by Editorial Board member Hyo-Choong Bang under the direction of Editor Hyun Seok Yang. This work was supported
by the Korea Research Foundation Grant (MOEHRD) KRF-2005-204-D00002, the Korea Science and Engineering Foundation(KOSEF) grant
funded by the Korea government(MOST) R0A-2007-000-10017-0 and Engineering Research Institute at Seoul National University.
Daewon Lee received the B.S. degree in Mechanical and Aerospace Engineering from Seoul National University (SNU), Seoul, Korea, in 2005,
where he is currently working toward a Ph.D. degree in Mechanical and Aerospace Engineering. He has been a member of the UAV
research team at SNU since 2005. His research interests include applications of nonlinear control and vision-based control
of UAV.
H. Jin Kim received the B.S. degree from Korea Advanced Institute of Technology (KAIST) in 1995, and the M.S. and Ph.D. degrees in Mechanical
Engineering from University of California, Berkeley in 1999 and 2001, respectively. From 2002–2004, she was a Postdoctoral
Researcher and Lecturer in Electrical Engineering and Computer Science (EECS), University of California, Berkeley (UC Berkeley).
From 2004–2009, she was an Assistant Professor in the School of in Mechanical and Aerospace Engineering at Seoul National
University (SNU), Seoul, Korea, where she is currently an Associate Professor. Her research interests include applications
of nonlinear control theory and artificial intelligence for robotics, motion planning algorithms.
Shankar Sastry received the B.Tech. degree from the Indian Institute of Technology, Bombay, in 1977, and the M.S. degree in EECS, the M.A.
degree in mathematics, and the Ph.D. degree in EECS from UC Berkeley, in 1979, 1980, and 1981, respectively. He is currently
Dean of the College of Engineering at UC Berkeley. He was formerly the Director of the Center for Information Technology Research
in the Interest of Society (CITRIS). He served as Chair of the EECS Department from January, 2001 through June 2004. In 2000,
he served as Director of the Information Technology Office at DARPA. From 1996 to 1999, he was the Director of the Electronics
Research Laboratory at Berkeley (an organized research unit on the Berkeley campus conducting research in computer sciences
and all aspects of electrical engineering). He is the NEC Distinguished Professor of Electrical Engineering and Computer Sciences
and holds faculty appointments in the Departments of Bioengineering, EECS and Mechanical Engineering. Prior to joining the
EECS faculty in 1983 he was a Professor with the Massachusetts Institute of Technology (MIT), Cambridge. He is a member of
the National Academy of Engineering and Fellow of the IEEE. 相似文献