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111.
Piotr Bania 《International journal of control》2013,86(10):2339-2348
An information-based control (IBC) has been formulated for a class of dual control problems with quadratic cost and unknown, constant parameters. Simple dual control problem has been solved by dynamic programming. Then, the solution was compared with the solution obtained by IBC. It has been shown that an appropriate choice of the intensity of learning allows to recover the optimal dual control for at least one nontrivial class of dual control problems. 相似文献
112.
Piotr Grabowski 《International journal of control》2013,86(8):1539-1563
A model of a heavy chain system with a punctual load (tip mass) in the form of a system of partial differential equations is interpreted as an abstract semigroup system on a Hilbert state space. Our aim is to solve the output motion planning problem of the same nature as in the case of an unloaded heavy chain (Grabowski, P. (2003), ‘Abstract Semigroup Model of Heavy Chain System with Application to a Motion Planning Problem’, in Proceedings of 9th IEEE International Conference: Methods and Models in Automation and Robotics, 25–28 August, Mi?dzyzdroje, Poland, pp. 77–86 (IS1-2-3.PDF)). In order to solve this problem we first analyse its well-posedness and some basic properties. Next, we solve the output motion planning problem using a substitute of the inverse of the input–output operator represented in terms of the Laplace transforms. A problem of exponential stabilisation is also formulated and solved using a stabiliser of the colocated type. The exponential stabilisation is proved using the method of Lyapunov functionals combined with some frequency-domain tools. The method of Lyapunov functionals can be replaced by the spectral or exact controllability approach as shown in the second part (Grabowski, P. (2008), ‘The Motion Planning Problem and Exponential Stabilisation of a Heavy Chain. Part II’, Opuscula Mathematica, 28 (2008) (Special issue dedicated to the memory of Professor Andrzej Lasota), 481–505) of the present article. A laboratory setup which allows verification of the results in practice is described in detail. Its dynamical model is used as an example to illustrate the theoretical results. 相似文献
113.
The continuous-time generalized predictive control (CGPC) using a long horizon cost function has superior robustness as compared to several other control strategies suitable for adaptive control. The main purpose of this paper is to put forward an analytical, explicit stable CGPC control design method for minimum-phase SISO systems that is based on a set of closed-loop characteristics with definite time-domain specifications. Explicit formulae for closed-loop characteristic polynomials are given and then the prototype design characteristic polynomials are catalogued that can serve as a basis for fully analytical design procedure assuring both the nominal stability and nominal performance specifications. A numerical example is given in order to illustrate the approach. 相似文献
114.
Piotr Piecuch Stanis?aw A. KucharskiKarol Kowalski Monika Musia? 《Computer Physics Communications》2002,149(2):71-96
The recently proposed renormalized (R) and completely renormalized (CR) coupled-cluster (CC) methods of the CCSD[T] and CCSD(T) types have been implemented using recursively generated intermediates and fast matrix multiplication routines. The details of this implementation, including the complete set of equations that have been used in writing efficient computer codes, memory requirements, and typical CPU timings, are discussed. The R-CCSD[T], R-CCSD(T), CR-CCSD[T], and CR-CCSD(T) computer codes and similar codes for the standard CC methods, including the LCCD, CCD, CCSD, CCSD[T], and CCSD(T) approaches, have been incorporated into the gamess package. Information about the main features of this new set of CC programs is provided. 相似文献
115.
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
116.
Paweł Jankowski Dominika Ogończyk Ladislav Derzsi Wojciech Lisowski Piotr Garstecki 《Microfluidics and nanofluidics》2013,14(3-4):597-604
Modification of the surfaces of polycarbonate (PC) with the use of a solution of tin (II) chloride renders them hydrophilic. The surface draping is stable against exposure to water and to alcohols. Exposure to alkanes reduces but does not diminish the effect. The method is compatible—in using the same solvent and temperature—with the hydrophobic modification of PC (Jankowski et al. in Lab Chip 11:1151–1156, 2011). The combination of these methods makes it possible to generate single and multiple monodisperse emulsions with the use of flow-focusing junctions in systems made in PC—a material that is suitable for fabrication of multilayer, high-throughput microfluidic devices. 相似文献
117.
Maria Jurzecka-Szymacha Piotr BoszkowiczKatarzyna Tkacz-?miech 《Thin solid films》2011,520(4):1308-1312
Two series of amorphous silicon nitride layers (a-SiNx:H) were formed with Radio Frequency Chemical Vapor Deposition method (13.56 MHz) from a NH3/SiH4 gas mixture: the first one on Si (001) and the second on glass. The deposition process was repeated at various [NH3]/[SiH4] ratios, while the other parameters (pressure, plasma generator power, substrate temperature, total gas flow, and time) were kept constant. It has been confirmed in optical measurements that the refractive indexes decrease for the layers obtained at increasing [NH3]/[SiH4] ratios. Simultaneously, the position of the band assigned to Si-H stretching vibrations (at about 2100 cm− 1) shifts towards higher frequencies. The observed dependencies were applied in evaluation of nitrogen and hydrogen contents in the respective layers. It has been shown that when [NH3]/[SiH4] increases from 0 (no silane flow) to 0.2 then the a-SiNx:H layers of x = [N]/[Si] increasing between 0 and nearly 1.4 may be obtained. The obtained layers have the refractive indexes higher than 2.1 and lower than 2.7 which make them good materials for antireflective coatings on crystalline and multicrystalline silicon solar cells. 相似文献
118.
This paper describes the Automated Reasoning for Mizar ( $\textsf{Miz}\mathbb{AR}$ ) service, which integrates several automated reasoning, artificial intelligence, and presentation tools with Mizar and its authoring environment. The service provides ATP assistance to Mizar authors in finding and explaining proofs, and offers generation of Mizar problems as challenges to ATP systems. The service is based on a sound translation from the Mizar language to that of first-order ATP systems, and relies on the recent progress in application of ATP systems in large theories containing tens of thousands of available facts. We present the main features of $\textsf{Miz}\mathbb{AR}$ services, followed by an account of initial experiments in finding proofs with the ATP assistance. Our initial experience indicates that the tool offers substantial help in exploring the Mizar library and in preparing new Mizar articles. 相似文献
119.
R-22的替代现状 总被引:9,自引:2,他引:9
张建君 《制冷与空调(北京)》2005,5(1):62-69
1背景 R~22于1928年最初被人们所认可,并于1936年开始商业化生产使用.迄今为止,R-22已经在很多系统中得到应用,从最小型的窗式空调到最大型的冷水机组和热泵,也包括那些区域性的冷却和加热系统.使用这种通用型制冷剂的单个设备的制冷功率在2 kW与30 MW之间(0.5冷吨到9,500冷吨).R-22的使用装置包括:旋转式活塞、往复式活塞、涡旋式、螺杆和离心式压缩机,在实验中还包括吸收循环装置.没有一种制冷剂能够像R-22这样有如此大的产量和如此广的应用范围. 相似文献
120.
Piotr Choida 《Communications Letters, IEEE》2007,11(2):200-200
For original paper by D.A. Schupke see ibid., vol.9, no 4, p.360-2, April 2005. It is shown that in the above letter by Schupke corollaries related to a necessary condition on the network to ensure that a set of Hamiltonian p-cycles is able to reach the theoretical logical redundancy bound are wrongly calculated 相似文献