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991.
This article describes using of new approach to automatic classification of big data records in Be and B[e] stars spectra in large astrophysical archives. With enormous amount of these data it is no longer feasible to analyse it using classical approaches. We introduce evolutionary synthesis of the classification by means of so called analytic programming (AP), one of methods of symbolic regression. By using this method, we synthesise the most suitable mathematical models that approximate chosen samples of the stellar spectra. As a result is then selected the class whose synthesised formula has the lowest difference (i.e. the most similar) compared to the particular spectrum. The results show us that classification of stellar spectra by means of AP is able to identify different shapes of the spectra and classify them.  相似文献   
992.
Direct matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) bacterial cell or lysate analysis appears to meet all the criteria required for a rapid and reliable analytical microorganism identification and taxonomical classification tool. Few-minute analytical procedure providing information extending up to sub-species level underlines the potential of the MALDI-MS profiling in comparison with other methods employed in the field. However, the quality of MALDI-MS profiles and consequently the performance of the method are influenced by numerous factors, which involve particular steps of the sample preparation procedure. This review is aimed at advances in development and optimization of the MALDI-MS profiling methodology. Approaches improving the quality of the MALDI-MS profiles and universal feasibility of the method are discussed.  相似文献   
993.
Summary Polydibromoacetylenes were synthesized under different polymerization conditions and with Al-Ti coordinative catalysts. For the characterization of the polymers and for the study of the correlation between polymerization conditions and properties of the polymers, 13C MAS NMR, ESR and UV spectroscopies were used. The electrical conductivity of the polymers was measured in dependence on temperature. The energy gap decreased with increased crystallinity. As compared to polyacetylene the conductivity of polydibromoacetylenes was lower, but the stability against oxygen was higher. The polydibromoacetylenes were thermal stabile up to 200°C.Dedicated to Professor Dragutin Fle on the occasion of his 70th birthday  相似文献   
994.
995.
Doping of alumina, yttria and zeolite 4A with small quantities of palladium (down to 0.025%) was done. It was shown that these oxides, which do not normally absorb hydrogen, after the doping acquire a considerable capacity for hydrogen absorption. The sorption of hydrogen is occurring by the spill-over effect from metallic palladium to the oxide. The process is exothermal, taking place in two stages between 60 and 350 °C. Activation energies of the first stage range from 120 to 167 kJ mol–1 and for the second one from 20 to 30 kJ mol–1. After cooling to room temperature in hydrogen flow, the samples are able to absorb considerable quantities of oxygen which reacts exothermally with the previously formed hydride. On next exposition to hydrogen, a vigorous reaction of it with the adsorbed oxygen is taking place already at room temperature. Enthalpies of hydrogen absorption, — H, are of the order of 10 kJ g–1, showing a tendency of increase after repeated exposures to hydrogen.  相似文献   
996.
The paper describes a general computational model for the simulation of contact fatigue-damage initiation in the contact area of meshing gears. The model considers the continuum mechanics approach, where the use of homogenous and elastic material is assumed. The stress field in the contact area and the relationship between the cyclic contact loading conditions and observed contact points on the tooth flank are simulated with moving Hertzian contact pressure in the framework of the finite element method analysis. An equivalent model of Hertzian contact between two cylinders is used for evaluating contact conditions at the major point of contact of meshing gears. For the purpose of fatigue-damage analysis, the model, which is used for prediction of the number of loading cycles required for initial fatigue damage to appear, is based on the Coffin-Manson relationship between deformations and loading cycles. On the basis of computational results, and with consideration of some particular geometrical and material parameters, the initiation life of contacting spur gears in regard to contact fatigue damage can be estimated.  相似文献   
997.
Virtually all applications which provide or require a security service need a secret key. In an ambient world, where (potentially) sensitive information is continually being gathered about us, it is critical that those keys be both securely deployed and safeguarded from compromise. In this paper, we provide solutions for secure key deployment and storage of keys in sensor networks and radio frequency identification systems based on the use of Physical Unclonable Functions (PUFs). In addition, to providing an overview of different existing PUF realizations, we introduce a PUF realization aimed at ultra-low cost applications. We then show how the properties of Fuzzy Extractors or Helper Data algorithms can be used to securely deploy secret keys to a low cost wireless node. Our protocols are more efficient (round complexity) and allow for lower costs compared to previously proposed ones. We also provide an overview of PUF applications aimed at solving the counterfeiting of goods and devices.
Geert-Jan SchrijenEmail:

Jorge Guajardo   is a senior scientist in the Information and System Security Department at Philips Research Europe. There he lead the efforts to design new and efficient methodologies to secure RFID systems and since 2007 has focus on the design of new anti-counterfeiting methodologies based on Physical Unclonable Functions (PUFs) and their applications to secure key storage and wireless sensor networks. Previous to joining Philips Research, Jorge worked for GTE Government Systems, RSA Laboratories, cv cryptovision gmbh, and Infineon Technologies AG. His interests include: the efficient implementation of cryptographic algorithms in constrained environments, the development of hardware architectures for private and public-key algorithms, provable security of cryptographic protocols under various assumptions, and the interplay of physics and cryptography to attain security goals. Jorge holds a B.Sc degree in physics and electrical engineering and M.S. in electrical engineering from Worcester Polytechnic Institute and a Ph.D. degree in electrical engineering and information sciences from the Ruhr-Universitaet Bochum obtained under the supervision of Prof. Christof Paar. Boris Škorić   received a PhD in theoretical physics from the University of Amsterdam, the Netherlands, in 1999. From 1999 to 2008 he was a research scientist at Philips Research in Eindhoven, working first on display physics and later on security topics. In 2008 he joined the faculty of Mathematics and Computer Science of Eindhoven Technical University, the Netherlands, as assistant professor. Pim Tuyls   studied Theoretical Physics at the Katholieke Universiteit of Leuven where he got a Ph.D. on Quantum Dynamical Entropy in 1997. Currently he works as Chief Technologist at Philips Intrinsic ID in the Netherlands where he is leading the crypto development activities. Since 2004, he is also a visiting professor at the Cosic institute in Leuven. His main interests are in Key Extraction from Noisy Data (Physical Unclonable Functions and Private Biometrics, Quantum Cryptography) and in applications of Secure Multi-Party Computation. Sandeep S. Kumar   is a Senior Researcher at Philips Research Europe. Kumar received both his B.Tech. and M.Tech. degrees in Electrical Engineering from IIT-Bombay, India in 2002. He received his Ph.D. degree in Communication Security from Ruhr University Bochum, Germany in 2006. His research interests include hardware and software architectures for implementations of cryptographic systems, in particular elliptic-curve cryptography on constrained devices. At Philips Research he has been working on hardware implementations of physically unclonable functions for anti-counterfeiting and presently on identity management systems for lifestyle applications. He is a member of the IACR. Thijs Bel   studied Chemical Differentation at the IHBO of Eindhoven. He obtained his certificate in 1984. In 1985 he joined Philips Research, first working on lithography for IC’s and later on lithography for several kinds of displays. In 2007 he joined the group Thin Film Facilities, where he has been working on PUFs and in 2008 he joined the group Device processing Facilities, working on OLEDs. Antoon H. M. Blom   studied electro technology at the Technical High School of s Hertogenbosch, where he graduated in 1978.In 1979 he joined the Philips Company at the mechanization department of the Volt site in Tilburg, a production site for wire wound components. After an intermediate period at the laboratory for tuning units and transformers within the consumer electronics department in Eindhoven, he joined the centre for manufacturing technologies, which has recently been merged with the Philips Applied Technologies department, where he is working in the Optics & Sensors group of the Process Technology department. Geert-Jan Schrijen   obtained his M.Sc. degree in Electrical Engineering from the University of Twente (Enschede) in December 2000. During his studies he specialized in digital signal processing and active noise cancellation. In April 2001 he joined Philips Research. As a research scientist he became interested in the fields of cryptography and information theory and worked several years on security technologies like Digital Rights Management (DRM) systems, low-power authentication protocols and private biometric systems. From 2005 he has been involved in the work on Physical Unclonable Functions (PUFs). Geert-Jan was appointed Chief Algorithm Development at the Philips Intrinsic-ID lab venture in April 2007, where he is focusing on the development of signal processing algorithms and security architectures around PUFs.  相似文献   
998.
In the paper, a well-known predictive functional control strategy is extended to nonlinear processes. In our approach the predictive functional control is combined with a fuzzy model of the process and formulated in the state space domain. The prediction is based on a global linear model in the state space domain. The global linear model is obtained by the fuzzy model in Takagi–Sugeno form and actually represents a model with changeable parameters. A simulation of the system, which exhibits a strong nonlinear behaviour together with underdamped dynamics, has evaluated the proposed fuzzy predictive control. In the case of underdamped dynamics, the classical formulation of predictive functional control is no longer possible. That was the main reason to extend the algorithm into the state space domain. It has been shown that, in the case of nonlinear processes, the approach using the fuzzy predictive control gives very promising results.  相似文献   
999.
In this paper an extended Kalman filter (EKF) is used in the simultaneous localisation and mapping (SLAM) of a four-wheeled mobile robot in an indoor environment. The robot’s pose and environment map are estimated from incremental encoders and from laser-range-finder (LRF) sensor readings. The map of the environment consists of line segments, which are estimated from the LRF’s scans. A good state convergence of the EKF is obtained using the proposed methods for the input- and output-noise covariance matrices’ estimation. The output-noise covariance matrix, consisting of the observed-line-features’ covariances, is estimated from the LRF’s measurements using the least-squares method. The experimental results from the localisation and SLAM experiments in the indoor environment show the applicability of the proposed approach. The main paper contribution is the improvement of the SLAM algorithm convergence due to the noise covariance matrices’ estimation.  相似文献   
1000.
The Belousov–Zhabotinsky reaction is used as an example of a self-organizing system which is easily and intelligibly observable, and experimentally accessible. The analysis does not require elaborate reconstruction of series of three-dimensional images as in the case of bird flocks, fish schools or organ behaviour. The analysis of living cells microscopic image series is even more elaborate. Moreover, the experimenter in the case of the chemical clock has full control of the mechanical constraints imposed on the system. In this, contributions are reported using both experimental and theoretical results of the BZ reaction as an experimental tool for the analysis of behaviour of the self-organizing system. We have created a state trajectory using several selected image identifiers (point information gain entropy – Hα). The Hα values define an approximate state space which may be analysed using multivariate analysis. In this report we provide results of this analysis.  相似文献   
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