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71.
The activity of ceramic honeycombs with varying material composition and degree of utilization is compared on a suitable model gas in a test plant. The tested honeycombs are standard products that have not been surface‐treated in any way. A propane‐air mixture was fed to the test plant and then oxidized in a high‐temperature furnace. The analysis of the conversion rate over the reaction temperature showed remarkable differences in activity. The honeycomb with the most promising results was further investigated with the exhaust gas from the drying process of a waste treatment plant. Finally, the activity of this honeycomb was assessed in a large‐scale trial in an existing running regenerative thermal oxidizer. 相似文献
72.
73.
Axel Poigné Matthew Morley Olivier Maffeïs Leszek Holenderski Reinhard Budde 《Formal Methods in System Design》1998,12(2):163-187
Synchronous programming is available through several formally defined languages having very different characteristics: Esterel is imperative, while Lustre and Signal are declarative in style; Statecharts and Argos are graphical languages that allow one to program by constructing hierarchical automata. Our motivation for taking the synchronous design paradigm further, integrating imperative, declarative (or dataflow), and graphical programming styles, is that real systems typically have components that match each of these profiles. This paper motivates our interest in the mixed language programming of embedded software around a number of examples, and sketches the semantical foundation of the Synchronie toolset which ensures a coherent computational model. This toolset supports a design trajectory that incorporates rapid prototyping and systematic testing for early design validation, an object oriented development methodology for long term software management, and formal verification at the level of automatically generated object code. 相似文献
74.
Sebastian Möser Patrick Degener Roland Wahl Reinhard Klein 《Computer Graphics Forum》2008,27(7):1853-1860
To assist wayfinding and navigation, the display of maps and driving directions on mobile devices is nowadays commonplace. While existing system can naturally exploit GPS information to facilitate orientation, the inherently limited screen space is often perceived as a drawback compared to traditional street maps as it constrains the perception of contextual information. Moreover, occlusion issues add to this problem if the environment is shown from the popular egocentric perspective. In this paper we describe an interactive visualization system that addresses these problems by reallocating the available screen space. At the heart of our system are three novel visualization techniques: First, we propose a non‐standard perspective that allows to blend between the familiar pedestrian perspective and a standard map depiction with reduced occlusion. Second, we derive an efficient deformation technique that allows an interactive allocation of screen space to areas of interest like e.g. nearby touristic attractions. Finally, a path adaptive isometric perspective is proposed that reveals otherwise hidden facades in top‐down views. We describe efficient implementations of all techniques and exemplify our interactive system on real world urban models. 相似文献
75.
Lehrer Christiane Eseryel U. Yeliz Rieder Annamina Jung Reinhard 《Electronic Markets》2021,31(4):747-764
Electronic Markets - Physical inactivity is a global public health problem that poses health risks to individuals and imposes financial burdens on already strained healthcare systems. Wearables... 相似文献
76.
Roland Tressl Klaus Günter Grünewald Hans Köppler und Reinhard Silwar 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1978,167(2):108-110
Zusammenfassung Dreißig Phenole wurden durch Destillation-Extraktion aus Röstkaffee isoliert, adsorptionschromatographisch von anderen Aromastoffen getrennt, durch GC-MS charakterisiert und grö-ßenordnungsmäßig bestimmt.Robusta-Kaffee enthielt die größten Mengen an Phenolen gefolgt vom neuen HybridArabusta (Côte d'Ivoire) andArabica. Neben der Sorte beeinflussen auch die Röstbedingungen Anzahl und Menge phenolischer Verbindungen.
Phenols in roasted coffees of different varieties. I.
Summary Thirty phenols were isolated from roasted coffee by distillation-extraction, separated from other constituents by adsorption-chromatography, and characterized by means of GC-MS.Robusta coffee contained the largest amount of phenols, followed byArabusta (Côte d'Ivoire) andArabica. Quantity and type of phenols depends on variety as well as on the roasting conditions.相似文献
77.
Jorge Lopez-Moreno Jorge JimenezSunil Hadap Ken AnjyoErik Reinhard Diego Gutierrez 《Computers & Graphics》2011,35(1):99-111
Recent works in image editing are opening up new possibilities to manipulate and enhance input images. Within this context, we leverage well-known characteristics of human perception along with a simple depth approximation algorithm to generate non-photorealistic renditions that would be difficult to achieve with existing methods. Once a perceptually plausible depth map is obtained from the input image, we show how simple algorithms yield powerful new depictions of such an image. Additionally, we show how artistic manipulation of depth maps can be used to create novel non-photorealistic versions, for which we provide the user with an intuitive interface. Our real-time implementation on graphics hardware allows the user to efficiently explore artistic possibilities for each image. We show results produced with six different styles proving the versatility of our approach, and validate our assumptions and simplifications by means of a user study. 相似文献
78.
Thethermodynamic state function free energy F(T,V,N) as function of the cluster distribution N and the thermodynamic parameters (temperature T and volume V) is calculated in the canonical ensemble. With the help of the Legendre transformation we get all other state functions for different boundary conditions. Monte Carlo simulations with 15000 particles starting from metastable homogeneous initial conditions are made for water and methanol. The Bethe-Weizsäcker ansatz and the Padé approximation are used for the binding energy of clusters. A first-order phase transition is observed under appropriate conditions. 相似文献
79.
A comparative evaluation of length estimators of digital curves 总被引:2,自引:0,他引:2
Coeurjolly D Klette R 《IEEE transactions on pattern analysis and machine intelligence》2004,26(2):252-258
This paper compares previously published length estimators in image analysis having digitized curves as input. The evaluation uses multigrid convergence (theoretical results and measured speed of convergence) and further measures as criteria. This paper also suggests a new gradient-based method for length estimation, and combines a previously proposed length estimator for straight segments with a polygonalization method. 相似文献
80.
IT infrastructure, such as servers and networking equipment, accounts for a large proportion of the IT costs in modern organizations.
Typically, this IT infrastructure is shared among multiple applications and customers. Cost allocation of shared IT infrastructure
is difficult and regularly based on biased cost allocation keys, which often causes free-rider problems. Measuring usage is
technically difficult and incurs high costs. In this paper we propose a method to derive adequate estimators for the resource
consumption of a customer-oriented service. These so-called resource profiles can then provide a basis for cost allocation
keys. The estimators are derived from a series of load tests, as they are typically done before an application is launched
in larger organizations. Such profiles need to be unbiased and precise even in cases of varying workloads and in rather heterogeneous
environments. We describe the results of a set of experiments in an infrastructure provided by the BMW Group, and illustrate
how the estimation can be integrated into existing IT service management processes. In our experiments we use Queuing Networks
to validate the estimated resource profiles under different workloads. 相似文献