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排序方式: 共有1162条查询结果,搜索用时 15 毫秒
71.
Delaunay P.-Y. Binh Minh Nguyen Hoffman D. Huang E.K.-W. Razeghi M. 《Quantum Electronics, IEEE Journal of》2009,45(2):157-162
The recent introduction of a M-structure design improved both the dark current and R0 A performances of type-II InAs-GaSb photodiodes. A focal plane array fabricated with this design was characterized at 81 K. The dark current of individual pixels was measured between 1.1 and 1.6 nA, 7 times lower than previous superlattice FPAs. This led to a higher dynamic range and longer integration times. The quantum efficiency of detectors without antireflective coating was 74%. The noise equivalent temperature difference reached 23 mK, limited only by the performance of the testing system and the read out integrated circuit. Background limited performances were demonstrated at 81 K for a 300 K background. 相似文献
72.
To create a programming environment for contract dispute resolution, we propose an extension of assumption-based argumentation
into modular assumption-based argumentation in which different modules of argumentation representing different knowledge bases
for reasoning about beliefs and facts and for representation and reasoning with the legal doctrines could be built and assembled
together. A distinct novel feature of modular argumentation in compare with other modular logic-based systems like Prolog
is that it allows references to different semantics in the same module at the same time, a feature critically important for
application of argumentation in legal domains like contract dispute resolution where the outcomes of court cases often depend
on whether credulous or skeptical modes of reasoning were applied by the contract parties. We apply the new framework to model
the doctrines of contract breach and mutual mistake. 相似文献
73.
A microtiter cell-culture method was developed and used to titrate virus isolates for characterization. Virus dilutions and chicken kidney cell suspensions were dispensed into the wells of disposable microculture plates, with infectivity endpoints being determined microscopically on the fifth or sixth day, or by reading crystal-violet-stained monolayers on day 6. With this method, 37 candidate avian adenoviruses isolated from diagnostic accessions were characterized as avian adenoviruses (AAV). The criteria used for characterization were production of round-cell cytopathic effect, resistance to chloroform treatment, inhibition by 5-bromodeoxyuridine, and the presence of an antigen showing identity with a known AAV by precipitation in agar gel. Statistical anlaysis of eight replicate titrations of three AAV indicated that the titration method was highly reproducible. Use of the microculture method for titrations gave substantial savings in indicator cells, media, incubator space, culture dishes, and time. 相似文献
74.
The electrochemical oxidation ofp-t-butyltoluene has been investigated. From several anode materials studied, Pb-Sb alloys give the best yields ofp-t-butylbenzaldehyde at 60° C in 1 M H2SO4. 相似文献
75.
An implementation of no-slip boundary conditions in DPD 总被引:3,自引:0,他引:3
We report an implementation of the no-slip boundary condition in the modeling of solid boundaries by dissipative particle dynamics (DPD) method. Stimulated by a model for several types of solid boundaries, we develop an implementation that satisfies no-slip boundary condition with practically no-density distortion near the boundaries. The model is implemented to simulate the planar Poiseuille and Couette flows, as well as the flow through a contraction and diffusion channel. Results compare excellently with the previous methods. 相似文献
76.
The surface of an evaporated thin film of the ionic conductor β-PbF2 was analysed using X-ray photoelectron spectroscopy (XPS). The results were compared with those obtained from nuclear and secondary ion mass spectrometry measurements. An analysis of the Au-β-PbF2 interface shows the presence of a thin layer of partly oxidized metallic lead. Part of this interfacial lead diffused across the gold film towards the external surface where it became bound to oxygen. An electrical analysis of the interface was performed by studying the capacitance as a function of the surface potential. The differences between experimental and calculated values are discussed in the light of the XPS measurements. 相似文献
77.
A novel two-dimensional piezoresistive nano-Newton resolution force sensing cantilever is presented. The silicon cantilever is fabricated using bulk micromachining. Two 500-nm-thick p-doped epitaxial silicon piezoresistive sensors are located on both sides of the cantilever. This structure detects both the lateral and vertical applied forces by electronic switching between two configurations of a Wheatstone bridge. A force sensitivity is measured up to 100 and 540 V/N for lateral and vertical configurations, respectively. The corresponding force resolution is estimated at 21 and 4 nN, respectively. This force-sensing cantilever can be used for measuring the contact force between manipulating tools and small objects in, e.g., living cell handling, minimally invasive surgery, and microassembly 相似文献
78.
Ig Mo Koo Tran Duc Trong Yoon Haeng Lee Hyungpil Moon Jachoon Koo Sun Kyu Park Hyouk Ryeol Choi 《Journal of Intelligent and Robotic Systems》2013,72(1):57-72
In this paper, we present a wall climbing robot system, called “LARVA”, developed for visual inspection of structures with flat surfaces. The robot has two differential driving wheels with a suspension and an adhesion mechanism. The adhesion mechanism is composed of an impeller and two–layered suction seals. It is designed to provide sufficient adhesion force and be controlled so that the robot can move freely on various wall surfaces. The static and aerodynamic modeling of the adhesion mechanism is given and the analysis of the adhesion mechanism, air leakage, and inner flow are carried out to be useful for the design as well as the control. Finally, the performances of the robot are experimentally verified on several kinds of walls and its feasibility is validated. 相似文献
79.
Anh Pham The Nguyen Duc Thang La The Vinh Young-Koo Lee Sungyoung Lee 《Applied Intelligence》2013,39(2):367-385
Spectral clustering (SC) is currently one of the most popular clustering techniques because of its advantages over conventional approaches such as K-means and hierarchical clustering. However, SC requires the use of computing eigenvectors, making it time consuming. To overcome this limitation, Lin and Cohen proposed the power iteration clustering (PIC) technique (Lin and Cohen in Proceedings of the 27th International Conference on Machine Learning, pp. 655–662, 2010), which is a simple and fast version of SC. Instead of finding the eigenvectors, PIC finds only one pseudo-eigenvector, which is a linear combination of the eigenvectors in linear time. However, in certain critical situations, using only one pseudo-eigenvector is not enough for clustering because of the inter-class collision problem. In this paper, we propose a novel method based on the deflation technique to compute multiple orthogonal pseudo-eigenvectors (orthogonality is used to avoid redundancy). Our method is more accurate than PIC but has the same computational complexity. Experiments on synthetic and real datasets demonstrate the improvement of our approach. 相似文献
80.
Motohiko Umeyama Duc Hoang Nguyen Cat Vu Minh Xuan Roanh Le Satoshi Motani 《Water Resources Management》2014,28(12):3937-3955
Despite many previous investigations, there is no theoretically justifiable equation to determine the freshwater discharge, tidal velocity, and salinity in a complex estuary that contains several branches. In this study, the longitudinal distributions of freshwater and salinity concentration in multi-branched estuaries are investigated using a mathematical model, considering the energy balance by frictional head loss and the salt balance by diffusion and advection in a one-dimensional steady-state condition. We attempt to obtain the time-mean freshwater discharge rate quantitatively at a junction where the main flow separates into two branches. The salinity distribution along each branch is calculated by following the dispersion coefficient equation previously proposed for a single estuary. The salinity field is divided into the near-coast region and the upstream region, because in each segment the inland velocity varies according to the tidal flux. For computing the tidal velocity, we propose the Burgers equation and the Hoph-Cole transformation. The theoretical results obtained by these equations were found to be in good agreement with a set of observed data in the Red River estuary system. 相似文献