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The EUBIONET III project has boosted (i) sustainable, transparent international biomass fuel trade, (ii) investments in best practice technologies and (iii) new services on biomass heat sector. Furthermore, it identified cost-efficient and value-adding use of biomass for energy and industry. The aims of this article are to provide a synthesis of the key results of this project. Estimated annual solid biomass potential in the EU-27 is almost 6600 PJ (157 Mtoe), of which 48% is currently utilised. The greatest potential for increased use lies in forest residues and herbaceous biomass. Trade barriers have been evaluated and some solutions suggested such as CN codes for wood pellets and price indexes for industrial wood pellets and wood chips. The analysis of wood pellet and wood chip prices revealed large difference amongst EU countries, but also that on the short term prices of woody and fossil fuels are barely correlated. Sustainable production and use of solid biomass are also deemed important by most European stakeholders, and many support the introduction of harmonised sustainability criteria, albeit under a number of preconditions. The study identified also that a number of woody and agro-industrial residue streams remain un- or underutilised. The estimated European total potential of agro-industrial sources is more than 250 PJ (7.2 Mtoe), the amount of unutilised woody biomass (the annual increment of growing stock) even amounts to 3150 PJ (75 Mtoe). Finally 35 case studies of biomass heating substituting fossil fuels were carried out, showing that the potential to reduce GHG emissions ranges between 90 and 98%, while costs are very similar to fossil fuel heating systems. Overall, we conclude that solid biomass is growing strongly, and is likely to heavily contribute to the EU renewable energy targets in the coming decade.  相似文献   
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Abstract

The asymptotic stability problem for a class of neutral systems with time‐varying delays and nonlinear uncertainties is investigated in this paper. LMI‐based delay‐dependent criteria are proposed to guarantee the asymptotic stability of the considered systems. New Lyapunov‐Krasovskii functional and Leibniz‐Newton formulae are used to find the delay‐dependent stability results. Finally, some numerical examples are illustrated to show the improved results from using this method.  相似文献   
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This article offers a fresh reading of the Water Framework Directive (WFD) and of the Common Implementation Strategy guidance document number 8 on public participation (PP) aimed at identifying the conditions required for successful implementation. We propose that a central barrier to implementing Article 14 is that Integrated Water Resources Management (IWRM) problems are complex in character and that participation is a wicked process in practice. This article highlights some ambiguous interpretations of the WFD comparing and contrasting the ‘letter of the law’ and its ‘spirit’, based on a critical review of the nature of PP, who it concerns and when it takes place. First we articulate a complex system interpretation of IWRM in the context of the WFD. Second, we explain the difficulty to define blueprint for PP in IWRM. Finally, we present five interpretative challenging readings in order to highlight tensions between the ‘spirit’ and the ‘letter’ of the WFD.  相似文献   
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A new charge pump circuit has been proposed to suppress the return-back leakage current without suffering the gate-oxide reliability problem in low-voltage CMOS process. The four-phase clocks were used to control the charge-transfer devices turning on and turning off alternately to suppress the return-back leakage current. A test chip has been implemented in a 65-nm CMOS process to verify the proposed charge pump circuit with four pumping stages. The measured output voltage is around 8.8 V with 1.8-V supply voltage to drive a capacitive output load, which is better than the conventional charge pump circuit with the same pumping stages. By reducing the return-back leakage current and without suffering gate-oxide overstress problem, the new proposed charge pump circuit is suitable for applications in low-voltage CMOS IC products.  相似文献   
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A new CMOS on-chip electrostatic discharge (ESD) protection circuit which consists of dual parasitic SCR structures is proposed and investigated. Experimental results show that with a small layout area of 8800 μ2, the protection circuit can successfully perform negative and positive ESD protection with failure thresholds greater than ±1 and ±10 kV in machine-mode (MM) and human-body-mode (HBM) testing, respectively. The low ESD trigger voltages in both SCRs can be readily achieved through proper circuit design and without involving device or junction breakdown. The input capacitance of the proposed protection circuit is very low and no diffusion resistor between I/O pad and internal circuits is required, so it is suitable for high-speed applications. Moreover, this ESD protection circuit is fully process compatible with CMOS technologies  相似文献   
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It is apparent that automated inspection for manufacturing is on the threshold of broad industrial utilization. One key problem in manufacturing applications of automated inspection is how to find fast and efficient methods using economical computers that industry can afford. Moreover, most mechanical designers set only overall tolerances for part geometric features. In computer vision inspection, as well as in the use of other automated inspection devices and coordinate measuring machines (CMM) the errors of representing each geometric features should be identified separately. The proposed statistical inference method provides a scientific basis for setting inspection tolerances in original geometric space which are compatible with engineering specifications.

The results of this presentation should supply industrial practitioners with an accurate and fast approach for on-line part profile inspection.  相似文献   

40.
Numerical simulation techniques are used to investigate the frequency dependence of the noise of the hysteretic rf SQUID up to frequencies on the order ofR/L. An exact lower bound for the noise of the instrument is given as a function of the parameters of the SQUID ring, pump frequency, and the temperature. This result is compared with the predictions of a scaling argument and with experiment.  相似文献   
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