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11.
Many computer users face problems in their interaction as a result of the native language employed by the application. The language of the application is often at variance with the native language of its users. This issue is frequently addressed through localization. In turn, localization generates a range of new problems. We propose an alternative to localization that is analogous to cinematic subtitles. This has the potential to reduce the user interaction defects that otherwise arise with localization whilst benefiting users through an additional channel of information in their own language. This paper outlines a prototype implementation and describes our initial evaluation of this approach. We suggest that our complementary ‘subtitles’ promise consistent support for all applications in the user's computing environment and yield a system that is expandable and much easier to maintain than pre-localized software.  相似文献   
12.
Giorgos Mellios 《Fuel》2007,86(15):2254-2261
An empirical model for the estimation of evaporative hydrocarbon emissions from canister-equipped vehicles has been developed from experimental data obtained from repeated tests on a single carbon canister. The model is able to predict canister adsorption and desorption behaviour under different loading and purging conditions and it calculates canister weight and breakthrough emissions for various experimental variables including temperature, mixture concentration and mass flow rate. The model enables the simulation of a full evaporative emission Sealed Housing for Evaporative Determination (SHED) test procedure taking into account vehicle-specific estimations of fuel vapour generation and permeation. Results from measurements conducted on a vehicle equipped with the same canister were used to calibrate the model. Model results were in good agreement with measured evaporative emissions from a number of vehicles.  相似文献   
13.
This paper presents a systematic noise analysis method for externally linear filters, suitable for hand calculations. As an illustrative example, a log-domain filter is analyzed. Applying this method to an abstract topology, bounds for signal-to-noise ratio are derived for a class of instantaneous companding filters, when total capacitance or total power are limited.  相似文献   
14.
The Delay-/Disruption-Tolerant Networking Architecture calls for new design principles that will govern data transmission and retransmission scheduling over challenged environments. In that context, novel routing, transport and application layer algorithms have to be established in order to achieve efficient and reliable communication between DTN-nodes.In this study, we focus on the evolution of the terrestrial Internet into the Interplanetary or Space Internet and propose adoption of the Deep-Space Transport Protocol (DS-TP) as the transport layer scheme of choice for the space networking protocol stack. We present DS-TP’s basic design principles and we evaluate its performance both theoretically and experimentally. We verify that practice conforms with theory and observe great performance boost, in terms of file delivery time between DTN-nodes, in case of DS-TP. In particular, the gain of DS-TP against conventional proposals for deep-space communications increases with the link error rate; under conditions DS-TP can improve the performance of the transport layer protocol by a factor of two (i.e., DS-TP can become two times faster than conventional protocols).  相似文献   
15.
An extension of the primitive normal basis theorem and its strong version is proved. Namely, we show that for nearly all \(A = {\small \left( \begin{array}{cc} a&{}b \\ c&{}d \end{array} \right) } \in \mathrm{GL}_2(\mathbb {F}_{q})\) , there exists some \(x\in \mathbb {F}_{q^m}\) such that both \(x\) and \((-dx+b)/(cx-a)\) are simultaneously primitive elements of \(\mathbb {F}_{q^m}\) and produce a normal basis of \(\mathbb {F}_{q^m}\) over \(\mathbb {F}_q\) , granted that \(q\) and \(m\) are large enough.  相似文献   
16.
Giorgos Boras  Xuezhe Yu  Huiyun Liu 《半导体学报》2019,40(10):101301-101301-27
Over the past decades, the progress in the growth of materials which can be applied to cutting-edge technologies in the field of electronics, optoelectronics and energy harvesting has been remarkable. Among the various materials, group III–V semiconductors are of particular interest and have been widely investigated due to their excellent optical properties and high carrier mobility. However, the integration of III–V structures as light sources and numerous other optical components on Si, which is the foundation for most optoelectronic and electronic integrated circuits, has been hindered by the large lattice mismatch between these compounds. This mismatch results in substantial amounts of strain and degradation of the performance of the devices. Nanowires (NWs) are unique nanostructures that induce elastic strain relaxation, allowing for the monolithic integration of III–V semiconductors on the cheap and mature Si platform. A technique that ensures flexibility and freedom in the design of NW structures is the growth of ternary III–V NWs, which offer a tuneable frame of optical characteristics, merely by adjusting their nominal composition. In this review, we will focus on the recent progress in the growth of ternary III–V NWs on Si substrates. After analysing the growth mechanisms that are being employed and describing the effect of strain in the NW growth, we will thoroughly inspect the available literature and present the growth methods, characterization and optical measurements of each of the III–V ternary alloys that have been demonstrated. The different properties and special treatments required for each of these material platforms are also discussed. Moreover, we will present the results from the works on device fabrication, including lasers, solar cells, water splitting devices, photodetectors and FETs, where ternary III–V NWs were used as building blocks. Through the current paper, we exhibit the up-to-date state in this field of research and summarize the important accomplishments of the past few years.  相似文献   
17.
Pyrrones derived from 1,2,4,5-tetraaminobenzene and pyromellitic dianhydride or 3,3′,4,4′-benzophenonetetracarboxylic dianhydride were prepared by catalytic reduction and cyclization of the poly(o-nitro)imides, obtained by polycondensation of 1,3-dichloro-4,6-dinitrobenzene with the dipotassium salt of pyromellitic diimide or 3,3′,4,4′-benzophenonetetracarboxylic diimide. These polymers were characterized by slightly better thermal stability as compared with the polymers of the same structure obtained by conventional methods. The model compound for these polymers has been also synthesized by catalytic reduction and cyclization of 1,3-bis(phthalimido)-4,6-dinitrobenzene.  相似文献   
18.
Atrial fibrillation (AF) is the most common cardiac arrhythmia and entails an increased risk of thromboembolic events. Prediction of the termination of an AF episode, based on noninvasive techniques, can benefit patients, doctors and health systems. The method described in this paper is based on two-lead surface electrocardiograms (ECGs): 1-min ECG recordings of AF episodes including N-type (not terminating within an hour after the end of the record), S-type (terminating 1 min after the end of the record) and T-type (terminating immediately after the end of the record). These records are organised into three learning sets (N, S and T) and two test sets (A and B). Starting from these ECGs, the atrial and ventricular activities were separated using beat classification and class averaged beat subtraction, followed by the evaluation of seven parameters representing atrial or ventricular activity. Stepwise discriminant analysis selected the set including dominant atrial frequency (DAF, index of atrial activity) and average HR (HRmean, index of ventricular activity) as optimal for discrimination between N/T-type episodes. The linear classifier, estimated on the 20 cases of the N and T learning sets, provided a performance of 90% on the 30 cases of a test set for the N/T-type discrimination. The same classifier led to correct classification in 89% of the 46 cases for N/S-type discrimination. The method has shown good results and seems to be suitable for clinical application, although a larger dataset would be very useful for improvement and validation of the algorithms and the development of an earlier predictor of paroxysmal AF spontaneous termination time.  相似文献   
19.
Ansari L  Fagas G  Colinge JP  Greer JC 《Nano letters》2012,12(5):2222-2227
Energy bandgaps are observed to increase with decreasing diameter due to quantum confinement in quasi-one-dimensional semiconductor nanostructures or nanowires. A similar effect is observed in semimetal nanowires for sufficiently small wire diameters: A bandgap is induced, and the semimetal nanowire becomes a semiconductor. We demonstrate that on the length scale on which the semimetal-semiconductor transition occurs, this enables the use of bandgap engineering to form a field-effect transistor near atomic dimensions and eliminates the need for doping in the transistor's source, channel, or drain. By removing the requirement to supply free carriers by introducing dopant impurities, quantum confinement allows for a materials engineering to overcome the primary obstacle to fabricating sub-5 nm transistors, enabling aggressive scaling to near atomic limits.  相似文献   
20.
We study the flows induced by different rework loops in serial manufacturing systems with inspection stations. Average values of these flows and queuing network formulas are used for performance evaluation and optimisation of production lines. An application is presented for solving jointly the problems of inventory control and inspection station allocation in a CONWIP production line.  相似文献   
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