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2.
We describe a new analog differential synchronous demodulator for AC signals where (i) the signal is synchronously demodulated using the floating-capacitor technique after being amplified, if necessary, by an AC amplifier with differential input and differential output, thus yielding a very high CMRR; and (ii) the differential-to-single-ended signal conversion is performed after demodulation, that is, on a low-frequency signal that can be amplified by low-cost, high-performance circuits. The possible signal-to-noise ratio degradation because of synchronous sampling is prevented by using bandpass differential filters  相似文献   
3.
OBJECTIVE: The clinical course of transitional cell carcinoma of the bladder can be difficult to predict due to its potential to invade the muscle layer and/or develop to a high grade lesion. Bladder carcinoma can arise from genetic changes that may activate the oncogenes (-c-erbB2, c-erbB1, c-myc, ras, etc.) and/or inactivate the suppressor genes (p53, Rb). The aim of the present study is to continue a study protocol on the molecular biology of bladder tumors. METHODS/RESULTS: From January, 1993 to January, 1995, 85 patients were studied. These patients were divided into two groups: the first group comprised 14 controls of urothelial tissue and the second comprised 65 cases of transitional cell carcinoma of the bladder. p53 expression was determined by an immunohistochemical method (NCL-p53-DO7 monoclonal antibody). Quantification of the p8 oncoprotein in cytosol and EGFR (epidermal growth factor receptor) in membrane was performed by ELISA (Oncogene Science) and RIA (Vienna Lab), respectively. A statistically significant relationship between the expression of p53 and EGFR with tumor stage and grade was found. Quantification of p185 and EGFR showed higher values in the tumor tissue than in the control samples, but a worse survival could not be determined. CONCLUSIONS: The present study shows that p53 expression can be considered to be a prognostic factor. It provides useful information on the aggressive behaviour of the tumor and has a direct relation with the survival rates.  相似文献   
4.
A theoretical and experimental study of the longitudinal propagation velocity of a normal phase along a superconducting cylindrical wire suspended in a superfluid helium bath is presented. The theoretical model supposes a moving nonplanar separating boundary between the normal and superconducting phases and takes into account the latent heat absorbed during the destruction of the superconducting state. The comparison of the measured and calculated normal zone propagating velocities versus the circulating electrical currents shows an excellent agreement for all the bath temperatures considered. A boundary thermal conductance across the wire wall and superfluid helium bath interface is inferred by adjusting the calculated velocities with the experimental data. The deduced boundary thermal conductance is similar to the Kapitza conductance in the sense that both are proportional to the superfluid helium bath temperature raised to a constant power. Furthermore the deduced boundary conductance seems unaffected by the dynamical aspect of the longitudinal destruction process of the superconducting state and by the heat flux range across the solid and He II separating boundary covered by the normal zone propagation velocity versus the circulating electrical current plots. To the authors knowledge this is the first study of heat transfer using the data obtained from longitudinal normal zone propagation experiments.  相似文献   
5.
This work is an experimental and theoretical study of antimony speciation and the solubility of Sb2O5, Sb2O3 and Sb2(SO4)3 at 298 K in aqueous sulphuric acid solutions (0 to 6 kmol/m3). A thermodynamic model was developed to quantify the solubility products and aqueous metal speciation. Main dissolved species were H3SbO3(aq) and H3SbO4(aq). The solubility of antimony increases with increasing solution acidity and with the presence of hydrogen peroxide in the solution. The following standard equilibrium constants at 298 K were obtained: Log K0(Sb2O5) = 11.7±0.5, Log K0(Sb2O3) = 32±1, and Log K0(Sb2(SO4)3) = 55±2.  相似文献   
6.
4D Video Textures (4DVT) introduce a novel representation for rendering video‐realistic interactive character animation from a database of 4D actor performance captured in a multiple camera studio. 4D performance capture reconstructs dynamic shape and appearance over time but is limited to free‐viewpoint video replay of the same motion. Interactive animation from 4D performance capture has so far been limited to surface shape only. 4DVT is the final piece in the puzzle enabling video‐realistic interactive animation through two contributions: a layered view‐dependent texture map representation which supports efficient storage, transmission and rendering from multiple view video capture; and a rendering approach that combines multiple 4DVT sequences in a parametric motion space, maintaining video quality rendering of dynamic surface appearance whilst allowing high‐level interactive control of character motion and viewpoint. 4DVT is demonstrated for multiple characters and evaluated both quantitatively and through a user‐study which confirms that the visual quality of captured video is maintained. The 4DVT representation achieves >90% reduction in size and halves the rendering cost.  相似文献   
7.
End-effectors are usually related to the location of limbs, and their reliable detection enables robust body tracking as well as accurate pose estimation. Recent innovation in depth cameras has re-stated the pose estimation problem. We focus on the information provided by these sensors, for which we borrow the name 2.5D data from the Graphics community. In this paper we propose a human pose estimation algorithm based on topological propagation. Geometric Deformable Models are used to carry out such propagation, implemented according to the Narrow Band Level Set approach. A variant of the latter method is proposed, including a density restriction which helps preserving the topological properties of the object under analysis. Principal end-effectors are extracted from a directed graph weighted with geodesic distances, also providing a skeletal-like structure describing human pose. An evaluation against reference methods is performed with promising results. The proposed solution allows a frame-wise end-effector detection, with no temporal tracking involved, which may be generalized to the tracking of other objects beyond human body.  相似文献   
8.

RILEM Draft Recommendation

Draft recommendation for damage classification of concrete structures  相似文献   
9.
Proteolytic and lipolytic activities of ninePenicillium strain and oneMucor strain previously isolated from Spanish dry fermented sausages have been studied.P. camemberti STCC 2267 andAspergillus oryzae ATCC 9362 were also used. Myofibrillar and sarcoplasmic proteins as well as fat extracted from pork meat and -naphthyl acetate, -naphthyl caprilate and -naphthyl laurate were used as substrates. Mould strains were grown in an enrichment medium prepared at pH 5.5 and 7.0 and malt extract broth. Strains were incubated at 18°C and 22°C. Myofibrillar proteins and -naphthyl caprilate were the most hydrolysed substrates. The greater enzymatic activities were observed at a pH 7.0 and 22°C. However, five mould strains showed considerable enzymatic activities under conditions similar to those used for ripening dry fermented sausages. These strains can be assayed as potential starter cultures for industrial sausage production.  相似文献   
10.
This paper presents a novel approach to deal with dynamic and highly uncertain traffic in dynamic network scenarios. The Reactive Robust Routing (RRR) approach is introduced, a combination of proactive and reactive techniques to improve network efficiency and robustness, simplifying network operation. RRR optimizes routing for normal-operation traffic, using a time-varying extension of the already established Robust Routing technique that outperforms the stable approach. To deal with anomalous and unexpected traffic variations, RRR uses a fast anomaly detection and localization algorithm that rapidly detects and localizes abrupt changes in traffic flows, permitting an accurate routing adaptation. This algorithm presents well-established optimality properties in terms of detection/localization rates and localization delay, which allows for generalization of results, independently of particular evaluations. The algorithm is based on a novel parsimonious model for traffic demands which allows for detection of anomalies using easily available aggregated-traffic measurements, reducing the overheads of data collection.  相似文献   
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