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81.
Björn Labitzke Serkan Bayraktar Andreas Kolb 《Data mining and knowledge discovery》2013,27(1):117-145
Multi- and hyperspectral imaging and data analysis has been investigated in the last decades in the context of various fields of application like remote sensing or microscopic spectroscopy. However, recent developments in sensor technology and a growing number of application areas require a more generic view on data analysis, that clearly expands the current, domain-specific approaches. In this context, we address the problem of interactive exploration of multi- and hyperspectral data, consisting of (semi-)automatic data analysis and scientific visualization in a comprehensive fashion. In this paper, we propose an approach that enables a generic interactive exploration and easy segmentation of multi- and hyperspectral data, based on characterizing spectra of an individual dataset, the so-called endmembers. Using the concepts of existing endmember extraction algorithms, we derive a visual analysis system, where the characteristic spectra initially identified serve as input to interactively tailor a problem-specific visual analysis by means of visual exploration. An optional outlier detection improves the robustness of the endmember detection and analysis. An adequate system feedback of the costly unmixing procedure for the spectral data with respect to the current set of endmembers is ensured by a novel technique for progressive unmixing and view update which is applied at user modification. The progressive unmixing is based on an efficient prediction scheme applied to previous unmixing results. We present a detailed evaluation of our system in terms of confocal Raman microscopy, common multispectral imaging and remote sensing. 相似文献
82.
Thomas Bernecker Tobias Emrich Hans-Peter Kriegel Nikos Mamoulis Matthias Renz Shiming Zhang Andreas Züfle 《GeoInformatica》2013,17(3):449-487
Traditional spatial queries return, for a given query object q, all database objects that satisfy a given predicate, such as epsilon range and k-nearest neighbors. This paper defines and studies inverse spatial queries, which, given a subset of database objects Q and a query predicate, return all objects which, if used as query objects with the predicate, contain Q in their result. We first show a straightforward solution for answering inverse spatial queries for any query predicate. Then, we propose a filter-and-refinement framework that can be used to improve efficiency. We show how to apply this framework on a variety of inverse queries, using appropriate space pruning strategies. In particular, we propose solutions for inverse epsilon range queries, inverse k-nearest neighbor queries, and inverse skyline queries. Furthermore, we show how to relax the definition of inverse queries in order to ensure non-empty result sets. Our experiments show that our framework is significantly more efficient than naive approaches. 相似文献
83.
Degradation of the lower chlorinated ethenes is crucial to the application of natural attenuation or in situ bioremediation on chlorinated ethene contaminated sites. Recently, within mixtures of several chloroethenes as they can occur in contaminated groundwater inhibiting effects on aerobic chloroethene degradation have been shown. The current study demonstrated that metabolic vinyl chloride (VC) degradation by an enrichment culture originating from groundwater was not affected by an equimolar concentration (50 μM) of cis-1,2-dichloroethene (cDCE). Only cDCE concentrations at a ratio of 2.4:1 (initial cDCE to VC concentration) caused minor inhibition of VC degradation. Furthermore, the degradation of VC was not affected by the presence of trans-1,2-dichloroethene (tDCE), 1,1-dichloroethene (1,1-DCE), trichloroethene (TCE), and tetrachloroethene (PCE) in equimolar concentrations (50 μM). Only cDCE and tDCE were cometabolically degraded in small amounts. The VC-degrading culture demonstrated a broad pH tolerance from 5 to 9 with an optimum between 6 and 7. Results also showed that the culture could degrade VC concentrations up to 1,800 μM (110 mg/L). 相似文献
84.
Christoph Spengler Marcus Huber Andreas Gabriel Beatrix C. Hiesmayr 《Quantum Information Processing》2013,12(1):269-278
Entanglement in high-dimensional many-body systems plays an increasingly vital role in the foundations and applications of quantum physics. In the present paper, we introduce a theoretical concept which allows to categorize multipartite states by the number of degrees of freedom being entangled. In this regard, we derive computable and experimentally friendly criteria for arbitrary multipartite qudit systems that enable to examine in how many degrees of freedom a mixed state is genuine multipartite entangled. 相似文献
85.
Michael Wand Alexander Berner Martin Bokeloh Philipp Jenke Arno Fleck Mark Hoffmann Benjamin Maier Dirk Staneker Andreas Schilling Hans-Peter Seidel 《Computers & Graphics》2008,32(2):204-220
This paper describes a new out-of-core multi-resolution data structure for real-time visualization, interactive editing and externally efficient processing of large point clouds. We describe an editing system that makes use of the novel data structure to provide interactive editing and preprocessing tools for large scanner data sets. Using the new data structure, we provide a complete tool chain for 3D scanner data processing, from data preprocessing and filtering to manual touch-up and real-time visualization. In particular, we describe an out-of-core outlier removal and bilateral geometry filtering algorithm, a toolset for interactive selection, painting, transformation, and filtering of huge out-of-core point-cloud data sets and a real-time rendering algorithm, which all use the same data structure as storage backend. The interactive tools work in real-time for small model modifications. For large scale editing operations, we employ a two-resolution approach where editing is planned in real-time and executed in an externally efficient offline computation afterwards. We evaluate our implementation on example data sets of sizes up to 63 GB, demonstrating that the proposed technique can be used effectively in real-world applications. 相似文献
86.
Nicolas Cuntz Andreas Kolb Robert Strzodka Daniel Weiskopf 《Computer Graphics Forum》2008,27(3):719-726
Typically, flow volumes are visualized by defining their boundary as iso‐surface of a level set function. Grid‐based level sets offer a good global representation but suffer from numerical diffusion of surface detail, whereas particle‐based methods preserve details more accurately but introduce the problem of unequal global representation. The particle level set (PLS) method combines the advantages of both approaches by interchanging the information between the grid and the particles. Our work demonstrates that the PLS technique can be adapted to volumetric dye advection via streak volumes, and to the visualization by time surfaces and path volumes. We achieve this with a modified and extended PLS, including a model for dye injection. A new algorithmic interpretation of PLS is introduced to exploit the efficiency of the GPU, leading to interactive visualization. Finally, we demonstrate the high quality and usefulness of PLS flow visualization by providing quantitative results on volume preservation and by discussing typical applications of 3D flow visualization. 相似文献
87.
Automatic Construction and Verification of Isotopy Invariants 总被引:1,自引:0,他引:1
Volker Sorge Andreas Meier Roy McCasland Simon Colton 《Journal of Automated Reasoning》2008,40(2-3):221-243
We extend our previous study of the automatic construction of isomorphic classification theorems for algebraic domains by
considering the isotopy equivalence relation. Isotopism is an important generalisation of isomorphism, and is studied by mathematicians in domains
such as loop theory. This extension was not straightforward, and we had to solve two major technical problems, namely, generating
and verifying isotopy invariants. Concentrating on the domain of loop theory, we have developed three novel techniques for
generating isotopic invariants, by using the notion of universal identities and by using constructions based on subblocks.
In addition, given the complexity of the theorems that verify that a conjunction of the invariants form an isotopy class,
we have developed ways of simplifying the problem of proving these theorems. Our techniques employ an interplay of computer
algebra, model generation, theorem proving, and satisfiability-solving methods. To demonstrate the power of the approach,
we generate isotopic classification theorems for loops of size 6 and 7, which extend the previously known enumeration results.
This work was previously beyond the capabilities of automated reasoning techniques.
The author’s work was supported by EPSRC MathFIT grant GR/S31099. 相似文献
88.
89.
J. Rögner B. Okolo S. Kurzenhäuser M. Müller W. Bauer H.-J. Ritzhaupt-Kleissl E. Kerscher V. Schulze 《Microsystem Technologies》2008,14(12):1831-1837
Due to size effects the mechanical behavior of micro-components with dimensions in the range of some 100 μm and structure
details of about 10 μm differs markedly from those of larger components. This is a crucial aspect for the design of micro-components
for applications where demands for high strength are critical. The present study, which was performed in the frame of the
Collaborative Research Centre 499 (SFB 499), approaches this issue by investigating the relationship between production process,
microstructure and the mechanical properties of micro-specimens made from zirconia using two different feedstocks. The specimens
were produced by a sintering process. The sintering temperature was varied between 1,300 and 1,500°C. Mechanical and tribological
behavior of the specimens was determined by three-point bending tests as well as static and sliding friction tests, respectively.
Properties derived from these tests were then correlated to the surface states in the specimens such as porosity, edge radius
and roughness. The strength of the micro-specimens was found to be significantly influenced by these surface features. Whilst
low porosity alone is not sufficient for high strength, notch effects resulting from pores as well as surface roughness can
lower the strength. With increasing edge radius the strength of the material also increases. The porosity, edge radius and
surface roughness were mathematically correlated with the strength to allow for a forecast. Within the SFB 499 feedstocks
with specific properties were designed and reliable processes were developed to guarantee desirable surface roughness and
porosity in the specimens. A characteristic bending strength of about 2,000 MPa is realizable in the micro-specimens within
a good statistical reliability. The tribological tests revealed that the wear properties of the zirconia micro-components
are strongly dependent on the quality of the feedstock. 相似文献
90.
Andreas Ruh Adam-Mwanga Dieckmann Richard Heldele Volker Piotter Robert Ruprecht Christian Munzinger Jürgen Fleischer Jürgen Haußelt 《Microsystem Technologies》2008,14(12):1805-1811
In the field of micro-technology the production of metallic and ceramic micro-components by powder injection molding (PIM)
has become a more and more established fabrication method. But in order to fulfill the demand for more complex-shaped high-precision
micro-components further development work has to be performed. This is especially true if more efficient production routes
for multi-component-micro-assemblies consisting of different materials or sub-components are envisaged. To meet these challenges,
investigations are performed to realize and to establish two primary shape micro-processes. These are two-component micro-injection
molding (2C-MicroPIM) and sinter-joining. The realization of these technologies will lead to a markedly reduction of the efforts
for handling, adjustment, and assembling of metallic and ceramic micro-assemblies. Furthermore, an increased integration level
and functionality can be yielded. For an effective transfer of scientific results to industrial applications the whole process
chain must be considered, from development and construction of the tooling as well as of the components to the quality assurance
and determination of the properties of the assemblies after sintering. These primary shape processes shall enable the mutual
processing of different materials within the fabrication process, so avoiding separate mounting or assembling steps. Additionally
fixed and loose junctions between at least two components shall be realized. The progress in research and development will
be demonstrated especially by the implementation of shaft-to-collar connections between micro-gearwheels and corresponding
shafts. Regarding two-component micro-injection molding, the tool construction for shaft-to-collar connections will be presented
as well as first experimental results on the properties of selected ceramic powders and feedstocks for the special requirements
of the 2C-MicroPIM process. With the assembly step being performed outside the injection molding tool before sinter-joining
different parts and geometries can be combined quite easily. The presented article gives an overview on the concept and on
preliminary testing results for the fabrication of a shaft-to-collar-connection. Additionally, a solution for an automated
assembly of a shaft and a toothed wheel outside the injection molding tool is presented. 相似文献