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991.
The impact of information technology (IT) on the business value of a cooperation has been an active research area for more than two decades. Although it is widely agreed that IT has a positive impact on the business values of cooperations an in-depth understanding of the underlying structures is still missing. Especially due to the huge investments in IT, there is still a need to better understand how IT influences the performance of cooperations and business values. Generally, the data collected in IT business value research to be quantitative as well as of qualitative nature. While quantitative data can be examined by classic econometric methods the analysis of qualitative data requires special methods. In the case of ordinal data DRSA – Dominance based Rough Sets Approach has been proposed. DRSA can be applied to induce rules out of a decision table containing ordinal data. This method has already successfully applied to such diverse areas like customer relationship management and satisfaction analysis, or the technical diagnostic of a fleet of vehicles besides others. In this article we apply it for the first time to the analysis of IT business value. We use ordinal data of a survey on IT management strategies of Australian firms conducted by the Australian Department of Communications, Information Technology and the Arts. The induces rules are interpreted and provide important insights into the impact of information technology on the business values of cooperations. Furthermore our study shows the potential of DRSA for information systems research where questionnaire are a widely applied technique to collect ordinal data.  相似文献   
992.
As part of its commitments to the Regional Greenhouse Gas Initiative (RGGI), the State of Maryland, USA, auctions emission permits to electric utilities, creating revenue that can be used to benefit consumers and the environment. This paper explores the CO2 emissions reductions that may be possible by allocating some of that revenue to foster efficiency improvements in the residential sector’s use of natural gas. Since these improvements will require changes to the capital stock of houses and end use equipment, efficiency improvements may be accompanied by economic and ancillary health impacts, both of which are quantified in this paper.  相似文献   
993.
Thin and Dense Ceramic Coatings by Plasma Spraying at Very Low Pressure   总被引:2,自引:0,他引:2  
The very low pressure plasma spray (VLPPS) process operates at a pressure range of approximately 100 Pa. At this pressure, the plasma jet interaction with the surrounding atmosphere is very weak. Thus, the plasma velocity is almost constant over a large distance from the nozzle exit. Furthermore, at these low pressures the collision frequency is distinctly reduced and the mean free path is strongly increased. As a consequence, at low pressure the specific enthalpy of the plasma is substantially higher, but at lower density. These particular plasma characteristics offer enhanced possibilities to spray thin and dense ceramics compared to conventional processes which operate in the pressure range between 5 and 20 kPa. This paper presents some examples of gas-tight and electrically insulating coatings with low thicknesses <50 μm for solid oxide fuel cell applications. Furthermore, plasma spraying of oxygen conducting membrane materials such as perovskites is discussed.  相似文献   
994.
Plasma spraying has become one of the most important thermal-spray technologies due to low operating costs, high deposition rates, and a high efficiency. It is especially suitable for producing coatings used to improve thermal, corrosion, and wear protection. The quality of coatings produced by thermal-spray processes are determined by particle characteristics, such as in-flight velocity, which can be investigated using various diagnostic systems. Velocity is a particularly relevant parameter for small particles, but it is difficult to measure. Hence, different velocity diagnostics must be validated for small injected particles. We compared the laser Doppler anemometry (LDA) system with the DPV-2000 system and measured the particle velocities of a F4 plasma torch. The results agreed well when the limited detectability of small particles by LDA was taken into account.  相似文献   
995.
996.
Electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP) measurements were used to study the ability of monocarboxylates to support the passivation of mild steel by dissolved oxygen in near neutral solution. It was shown that the effectiveness of monocarboxylates depends on their ability to form weakly soluble Fe(III) compounds and to adsorb on the oxide covered surface. The inhibition effect can be improved by an addition of a second inhibitor.  相似文献   
997.
A series of thick-wall cylinder tests were performed on Bentheim sandstone to investigate the nucleation and propagation of borehole breakouts. Isotropic compression tests showed a significant decrease of the critical pressure required to nucleate breakouts with increasing borehole diameter. Advanced analysis of acoustic emission radiation and optical microstructures indicate a three stage process of breakout nucleation and growth. Relatively few acoustic emissions are observed during the elastic loading stage of the specimens. Once breakout nucleation has occurred at the borehole wall a drastic increase of acoustic emission activity is observed. A close spatial correspondence between located acoustic events and the breakout indicates formation of two symmetric cusp-shaped breakouts on opposite sides of the borehole. With increasing isotropic pressure the breakouts grow forming parallel-sided slots that are surrounded by a process zone revealing grain crushing and pore collapse as typically observed in experimentally produced compaction bands. We apply a simple fracture mechanics approach to predict the observed size effect of the critical pressure required to initiate breakouts.  相似文献   
998.
The present study investigates the friction stir welding (FSW) process of extremely curved surfaces using a high payload industrial robot. The welding process of aluminum alloys in a butt joint configuration has been investigated over convex surface radii ranging from 104.5 to 14.5 mm. The weld qualities of the produced joints have been assessed by macrographs and tensile tests. It was shown that the FSW process needs an optimization of the welding path as well as an optional adaptation of the process parameters in the curved region in order to produce sound and reproducible joints without inner or outer defects. The results contribute to further fields of application where non-linear welds have to be produced.  相似文献   
999.
Consider learning tasks where the precision requirement is very high, for example a 99 % precision requirement for a video classification application. We report that when very different sources of evidence such as text, audio, and video features are available, combining the outputs of base classifiers trained on each feature type separately, aka late fusion, can substantially increase the recall of the combination at high precisions, compared to the performance of a single classifier trained on all the feature types, i.e., early fusion, or compared to the individual base classifiers. We show how the probability of a joint false-positive mistake can be less—in some cases significantly less—than the product of individual probabilities of conditional false-positive mistakes (a NoisyOR combination). Our analysis highlights a simple key criterion for this boosted precision phenomenon and justifies referring to such feature families as (nearly) independent. We assess the relevant factors for achieving high precision empirically, and explore combination techniques informed by the analysis.  相似文献   
1000.
This work presents a fast and robust method to precisely segment and locate boreholes of 4–50 mm diameter. The task is solved by scanning over the expected borehole location given by CAD data. Since the diameter of the borehole is known, this can be used to obtain a robust and fast algorithm suitable for industrial application. Single scan data is sufficient to segment the bore independent of bore chamfer type using a robust normal vector fit and a classification based on the Gaussian image. A sequential cylinder fit algorithm makes it possible to calculate the bore pose in less than one second. The experiments demonstrate that 120° of the borehole surface are sufficient for robust localization within 0.3 mm and 0.5° even in the presence of ghost points and notches in the boreholes.  相似文献   
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