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61.

Flying Ad-hoc Network (FANET) is a new class of Mobile Ad-hoc Network in which the nodes move in three-dimensional (3-D) ways in the air simultaneously. These nodes are known as Unmanned Aerial Vehicles (UAVs) that are operated live remotely or by the pre-defined mechanism which involves no human personnel. Due to the high mobility of nodes and dynamic topology, link stability is a research challenge in FANET. From this viewpoint, recent research has focused on link stability with the highest threshold value by maximizing Packet Delivery Ratio and minimizing End-to-End Delay. In this paper, a hybrid scheme named Delay and Link Stability Aware (DLSA) routing scheme has been proposed with the contrast of Distributed Priority Tree-based Routing and Link Stability Estimation-based Routing FANET’s existing routing schemes. Unlike existing schemes, the proposed scheme possesses the features of collaborative data forwarding and link stability. The simulation results have shown the improved performance of the proposed DLSA routing protocol in contrast to the selected existing ones DPTR and LEPR in terms of E2ED, PDR, Network Lifetime, and Transmission Loss. The Average E2ED in milliseconds of DLSA was measured 0.457 while DPTR was 1.492 and LEPR was 1.006. Similarly, the Average PDR in %age of DLSA measured 3.106 while DPTR was 2.303 and LEPR was 0.682. The average Network Lifetime of DLSA measured 62.141 while DPTR was 23.026 and LEPR was 27.298. At finally, the Average Transmission Loss in dBm of DLSA measured 0.975 while DPTR was 1.053 and LEPR was 1.227.

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Structural metallic materials with excellent functional performance and lightweight features have always been the goal of material scientists' pursuit.In this work,laminated metal composites of different thicknesses(less than 0.4 mm) composed of structural materials with great differences in deformation ability were successfully fabricated via a novel processing procedure.Ultra-high strength and excellent soft magnetic properties were combined perfectly in the ultra-thin and super-light laminated metal composite strips due to unique structural design and essential attributes of the initial materials.These results emphasize the significant potential application value of the ultra-thin laminated metal composites in the field of structural and functional integration.  相似文献   
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Characterization results on hydrogenated microcrystalline silicon (μc-Si:H) thin films grown in a Saddle Field (SF) PECVD system are presented. The microcrystalline content of the films is controlled by the application of a positive electrical bias to the film growth surface. The results of photoluminescence, atomic force microscopy, infrared-absorption, and electrical conductivity studies are presented. The results correlate to the changing microcrystalline content of the films in the same way as when microcrystalline content is influenced through growth parameters such as hydrogen dilution in other CVD techniques.
Stefan ZukotynskiEmail:
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A series of silica–epoxy nanocomposites were prepared by hydrolysis of tetraethoxysilane within the organic matrix at different processing temperatures, i.e., 25 and 60 °C. Epoxy matrices reinforced with 2.0–10.0 wt% silica were subsequently crosslinked with an aliphatic diamine hardener to give optically transparent nanocomposite films. Interphase connections between silica networks and organic matrix were established by in situ functionalization of silica with 2.0 wt% γ-aminopropyltriethoxysilane (APTS). The microstructure of silica–epoxy nanocomposites as studied by transmission electron microscopy indicated the formation of very well-matched nanocomposites with homogeneous distribution of silica at relatively higher temperatures and in the presence of APTS. Thermogravimetric and static mechanical analyses confirmed considerable increase in thermal stability, stiffness, and toughness of the modified composite materials as compared to neat epoxy polymer and unmodified silica–epoxy nanocomposites. A slight improvement in the glass transition temperatures was also recorded by differential scanning calorimetry measurements. High temperature of hydrolysis during the in situ sol–gel process not only improved reaction kinetics but also promoted mutual solubility of the two phases, and consequently enhanced the interface strength. In addition, APTS influenced the size and distribution of the inorganic domain and resulted in better performance of the modified silica–epoxy nanocomposites.  相似文献   
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The Mn-doped compounds Bi1.4La0.6Sr2CaCu2Oy were prepared by sol-gel method. The structural variation was characterized systematically by X-ray diffraction (XRD), infrared (IR) spectra and Raman scattering spectra, respectively. The electrical and magnetic properties of the compounds were investigated by the temperature dependence of resistivity (R-T) and magnetic hysteresis loop (M (H)) measurements. Results indicate that the subtle change of lattice parameters has taken place in the compounds, which is attributed to CuO2 planes canting and Mn valence alternation. In the condition of preserving Bi-2212 structure, Bi1.4La0.6Sr2CaCu2−xMnxOy compound has optimal resistivity and magnetism at x = 2%, which could provide a candidate as new barrier in Josephson junction in future.  相似文献   
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This paper addresses a holistic mathematical design using a novel approach for understanding the mechanism of cathodic delamination. The approach employed a set of interdependent parallel processes with each process representing: cation formation, oxygen reduction and cation transport mechanism, respectively. Novel mathematical equations have been developed for each of the processes based on the observations recorded from experimentation. These equations are then solved using efficient time-iterated algorithms. Each process consists of distinct algorithms which communicate with each other using duplex channels carrying signals. Each signal represents a distinct delamination parameter. As a result of interdependency of various processes and their parallel behaviour, it is much easier to analyse the quantitative agreement between various delamination parameters. The developed modelling approach provides an efficient and reliable prediction method for the delamination failure. The results obtained are in good agreement with the previously reported experimental interpretations and numerical results. This model provides a foundation for the future research within the area of coating failure analysis and prediction.  相似文献   
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In all fullerene-producing systems, reaction products were black soot extracts reported to contain a 5-25% fullerene mixture. Toluene extraction of the soot results in a solution of C60, C70, and higherc fullerenes. Without separation, absolute determination of the contents is not possible, leaving the researcher to comment only on the C60/C70 ratio of the solution. High-performance liquid chromatography, nuclear magnetic resonance, and scanning tunneling microscopy imaging techniques were reported in the literature for determining the C60/C70 ratio of the mixtures. These methods require tedious experiments and produce slightly differing results as well. In this communication, a new and relatively quick method is proposed for the simultaneous determination of the yields of C60 and C70 (not the ratio) in fullerene-containing solutions by ultraviolet-visible spectrophotometric analysis.  相似文献   
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