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51.
Frank-Michael Schleif Mathias Lindemann Mario Diaz Peter Maaß Jens Decker Thomas Elssner Michael Kuhn Herbert Thiele 《Computing and Visualization in Science》2009,12(4):189-199
Automatic classification of high-resolution mass spectrometry data has increasing potential to support physicians in diagnosis of diseases like cancer. The proteomic data exhibit variations among different disease states. A precise and reliable classification of mass spectra is essential for a successful diagnosis and treatment. The underlying process to obtain such reliable classification results is a crucial point. In this paper such a method is explained and a corresponding semi automatic parameterization procedure is derived. Thereby a simple straightforward classification procedure to assign mass spectra to a particular disease state is derived. The method is based on an initial preprocessing stage of the whole set of spectra followed by the bi-orthogonal discrete wavelet transform (DWT) for feature extraction. The approximation coefficients calculated from the scaling function exhibit a high peak pattern matching property and feature a denoising of the spectrum. The discriminating coefficients, selected by the Kolmogorov–Smirnov test are finally used as features for training and testing a support vector machine with both a linear and a radial basis kernel. For comparison the peak areas obtained with the it ClinProt-System 1 [33] were analyzed using the same support vector machines. The introduced approach was evaluated on clinical MALDI-MS data sets with two classes each originating from cancer studies. The cross validated error rates using the wavelet coefficients where better than those obtained from the peak areas2. 相似文献
52.
We investigate the use of the rough set model for financial time-series data analysis and forecasting. The rough set model is an emerging technique for dealing with vagueness and uncertainty in data. It has many advantages over other techniques, such as fuzzy sets and neural networks, including attribute reduction and variable partitioning of data. These characteristics can be very useful for improving the quality of results from data analysis. We demonstrate a rough set data analysis model for the discovery of decision rules from time series data for example, the New Zealand stock exchanges. Rules are generated through reducts and can be used for future prediction. A unique ranking system for the decision rules based both on strength of the rule and stability of the rule is used in this study. The ranking system gives the user confidence regarding their market decisions. Our experiment results indicate that the forecasting of future stock index values using rough sets obtains decision ruleswith high accuracy and coverage. 相似文献
53.
54.
JM Herbert JP Hérault A Bernat RG van Amsterdam JC Lormeau M Petitou C van Boeckel P Hoffmann DG Meuleman 《Canadian Metallurgical Quarterly》1998,91(11):4197-4205
SANORG 34006 is a new sulfated pentasaccharide obtained by chemical synthesis. It is an analog of the "synthetic pentasaccharide" (SR 90107/ ORG 31540) which represents the antithrombin (AT) binding site of heparin. SANORG 34006 showed a higher affinity to human AT than SR 90107/ORG 31540 (kd = 1.4 +/- 0.3 v 48 +/- 11 nmol/L), and it is a potent and selective catalyst of the inhibitory effect of AT on factor Xa (1,240 +/- 15 anti-factor Xa U/mg v 850 +/- 27 anti-factor Xa U/mg for SR 90107/ORG 31540). In vitro, SANORG 34006 inhibited thrombin generation occurring via both the extrinsic and intrinsic pathway. After intravenous (IV) or subcutaneous (SC) administration to rabbits, SANORG 34006 displayed a long-lasting anti-factor Xa activity and inhibition of thrombin generation (TG) ex vivo. SANORG 34006 was slowly eliminated after IV or SC administration to rats, rabbits, and baboons, showed exceptionally long half-lives (between 9.2 hours in rats and 61.9 hours in baboons), and revealed an SC bioavailability near 100%. SANORG 34006 displayed antithrombotic activity by virtue of its potentiation of the anti-factor Xa activity of AT. It strongly inhibited thrombus formation in experimental models of thromboplastin/stasis-induced venous thrombosis in rats (IV) and rabbits (SC) (ED50 values = 40.0 +/- 3.4 and 105.0 +/- 9.4 nmol/kg, respectively). The duration of its antithrombotic effects closely paralleled the ex vivo anti-factor Xa activity. SANORG 34006 enhanced rt-PA-induced thrombolysis and inhibited accretion of 125I-fibrinogen onto a preformed thrombus in the rabbit jugular vein suggesting that concomitant use of SANORG 34006 during rt-PA therapy might be helpful in facilitating thrombolysis and preventing fibrin accretion onto the thrombus under lysis. Contrary to standard heparin, SANORG 34006 did not enhance bleeding in a rabbit ear incision model at a dose that equals 10 times the antithrombotic ED50 in this species and, therefore, exhibited a favorable therapeutic index. We suggest that SANORG 34006 is a promising compound in the treatment and prevention of various thrombotic diseases. 相似文献
55.
Alessandra Di Pierro Chris Hankin Herbert Wiklicky 《International Journal of Information Security》2011,10(2):61-61
Preface
Preface 相似文献56.
Zusammenfassung Der Beitrag basiert auf der Annahme, dass das IT-Controlling in zweifacher Hinsicht unter einem Integrationsdefizit leidet.
Dies gilt zum einen für die unbefriedigende Synchronisation der Forschung mit Entwicklungen in der Praxis, zum anderen für
die unzureichende Verzahnung mit den Methoden der Wirtschaftsinformatik. Ausgehend von dieser Annahme untersucht der Beitrag
die historische Entwicklung des IT-Controllings, um daraus Thesen zum Integrationsstand abzuleiten. Die Untersuchung kommt
zu dem Ergebnis, dass Hinweise auf – nach wie vor – ungenutzte Integrationspotenziale vorliegen und identifiziert Potenziale
einer weiter gehenden Integration. Aus der Analyse identifizierter Integrationspotenziale werden Anforderungen an eine methodenbezogene
Integration abgeleitet und die Realisierung von Integrationspotenzialen an zwei Beispielen illustriert.
This article is also available in English via and : Strecker S, Kargl H (2009) Integration Deficits of IT Controlling – Historical Background, Analysis of Integration Potentials
and Method Integration. Bus Inf Syst Eng. doi: 10.1007/s12599-009-0053-4. 相似文献
57.
A simple robust control for global asymptotic position stabilization of underactuated surface vessels
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Global asymptotic stabilization of underactuated surface vessels is generally achieved only by designing complicated controllers. This paper proposes a very simple control law that globally asymptotically stabilizes the position of underactuated surface vessel to a desired constant location and its velocities to zero. The proposed controller is independent of velocity signals and is robust to model parameters. It neither includes an observer nor an adaptive/sliding‐mode law. Controller development and stability analysis rely on a novel Lyapunov function and LaSalle's theorem. Furthermore, by extending the proposed control strategy, a saturated control law is also obtained ensuring the semiglobal asymptotic stability of position error system. Effectiveness of the proposed control schemes is demonstrated by simulation examples. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
58.
Herbert Van de Sompel Ryan Chute Patrick Hochstenbach 《International Journal on Digital Libraries》2008,9(2):83-100
The need to federate repositories emerges in two distinctive scenarios. In one scenario, scalability-related problems in the
operation of a repository reach a point beyond which continued service requires parallelization and hence federation of the
repository infrastructure. In the other scenario, multiple distributed repositories manage collections of interest to certain
communities or applications, and federation is an approach to present a unified perspective across these repositories. The
high-level, 3-Tier aDORe federation architecture can be used as a guideline to federate repositories in both cases. This paper
describes the architecture, consisting of core interfaces for federated repositories in Tier-1, two shared infrastructure
components in Tier-2, and a single-point of access to the federation in Tier-3. The paper also illustrates two large-scale
deployments of the aDORe federation architecture: the aDORe Archive repository (over 100,000,000 digital objects) at the Los
Alamos National Laboratory and the Ghent University Image Repository federation (multiple terabytes of image files). 相似文献
59.
Alessandra Di Pierro Pascal Sotin Herbert Wiklicky 《Electronic Notes in Theoretical Computer Science》2008,220(3):23
Within the context of a quantitative generalisation of the well established framework of Abstract Interpretation – i.e. Probabilistic Abstract Interpretation – we investigate a quantitative notion of precision which allows us to compare analyses on the basis of their expected exactness for a given program. We illustrate this approach by considering various types of numerical abstractions of the values of variables for independent analysis as well as weakly and fully relational analysis. We utilise for this a linear operator semantics of a simple imperative programming language. In this setting, fully relational dependencies are realised via the tensor product. Independent analyses and weakly relational analyses are realised as abstractions of the fully relational analysis. 相似文献
60.
Herbert Wieser Wolfgang Stempfl Werner Grosch und Hans-Dieter Belitz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(6):447-449
Zusammenfassung Achtzehn Fettsäuren, Fettsäuremethylester und Fettalkohole, emulgiert in Wasser mit Sucrosepalmitatstearat, wurden auf ihre Geschmacksqualität untersucht; bei bitterschmeckenden Verbindungen wurden die Schwellenwerte bestimmt. Die Intensität des Bittergeschmacks von Fettsäuren und Fettalkoholen hängt von der Länge des Alkylrestes sowie von der Anzahl, der Konfiguration und der Position der Doppelbindungen ab. Linol- und Linolensäuremethylester schmecken nicht bitter. -Linolenylalkohol und -Linolensäure haben die niedrigsten Schwellenwerte (0,2–0,5 bzw. 0,6–1,2 mmol/l) und liegen etwa im gleichen Bereich wie Coffein (0,8–1,2 mmol/l).
Studies of the bitter taste of fatty acid emulsions
Summary Eighteen fatty acids, methyl esters of fatty acids and fatty alcohols emulsified in water with sucrose palmitate stearate were tested for taste quality. In the case of bitter tasting compounds the taste thresholds were determined. The intensity of bitter taste of fatty acids and fatty alcohols is dependent on the length of the hydrocarbon chain and on the number, the configuration and the positions of double bonds. The methyl esters of linoleic and linolenic acid are not bitter. Gamma-linolenyl alcohol and alphalinolenic acid have the lowest threshold values (0.2–0.5 and 0.6–1.2 mmol/l), similar to that of caffeine (0.8–1.2 mmol/l).相似文献