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101.
Yuhua Cheng Min-Chie Jeng Zhihong Liu Jianhui Huang Mansun Chan Kai Chen Ping Keung Ko Chenming Hu 《Electron Devices, IEEE Transactions on》1997,44(2):277-287
A new physical and continuous BSIM (Berkeley Short-Channel IGFET Model) I-V model in BSIM3v3 is presented for circuit simulation. Including the major physical effects in state-of-the art MOS devices, the model describes current characteristics from subthreshold to strong inversion as well as from the linear to the saturation operating regions with a single I-V expression, and guarantees the continuities of Ids, conductances and their derivatives throughout all Vgs, Vds, and Tbs, bias conditions. Compared with the previous BSIM models, the improved model continuity enhances the convergence property of the circuit simulators. Furthermore, the model accuracy has also been enhanced by including the dependencies of geometry and bias of parasitic series resistances, narrow width, bulk charge, and DIBL effects. The new model has the extensive built-in dependencies of important dimensional and processing parameters (e.g., channel length, width, gate oxide thickness, junction depth, substrate doping concentration, etc.). It allows users to accurately describe the MOSFET characteristics over a wide range of channel lengths and widths for various technologies, and is attractive for statistical modeling. The model has been implemented in the circuit simulators such as Spectre, Hspice, SmartSpice, Spice3e2, and so on 相似文献
102.
A. T. Fiory S. G. Chawda S. Madishetty V. R. Mehta N. M. Ravindra S. P. Mccoy M. E. Lefrançois K. K. Bourdelle J. M. Mckinley H. -J. L. Gossmann A. Agarwal 《Journal of Electronic Materials》2002,31(10):999-1003
Shallow junctions are formed in crystalline Si by low-energy ion implantation of B+, P+, or As+ species accompanied by electrical activation of dopants by rapid thermal annealing and the special case of spike annealing.
Diffusion depths were determined by secondary ion-mass spectroscopy (SIMS). Electrical activation was characterized by sheet
resistance, Hall coefficient, and reverse-bias diode-leakage measurements. The B+ and P+ species exhibit transient-enhanced diffusion (TED) caused by transient excess populations of Si interstitials. The electrically
activated fraction of implanted dopants depends mainly on the temperature for B+ species, while for P+ species, it depends on both temperature and P+ dose. The relatively small amount of diffusion associated with As+ implants is favorable for shallow-junction formation with spike annealing. 相似文献
103.
F.M. Gonçalves M.B. Santos I.C. Teixeira J.P. Teixeira 《Journal of Electronic Testing》2002,18(3):285-294
The purpose of this paper is to present a methodology and tools for the design and test of an EN298 compliant ASIC chip for a safety-critical gas burner control system. Safe operation, as far as the critical variable is concerned, is guaranteed in the presence of two simultaneous faults. Emphasis is put on circumventing methodology, EDA (Electronic Design Automation) and foundry limitations and on product certification requirements. 相似文献
104.
H Ertan Cetingül Yücel Yemez Engin Erzin A Murat Tekalp 《IEEE transactions on image processing》2006,15(10):2879-2891
There have been several studies that jointly use audio, lip intensity, and lip geometry information for speaker identification and speech-reading applications. This paper proposes using explicit lip motion information, instead of or in addition to lip intensity and/or geometry information, for speaker identification and speech-reading within a unified feature selection and discrimination analysis framework, and addresses two important issues: 1) Is using explicit lip motion information useful, and, 2) if so, what are the best lip motion features for these two applications? The best lip motion features for speaker identification are considered to be those that result in the highest discrimination of individual speakers in a population, whereas for speech-reading, the best features are those providing the highest phoneme/word/phrase recognition rate. Several lip motion feature candidates have been considered including dense motion features within a bounding box about the lip, lip contour motion features, and combination of these with lip shape features. Furthermore, a novel two-stage, spatial, and temporal discrimination analysis is introduced to select the best lip motion features for speaker identification and speech-reading applications. Experimental results using an hidden-Markov-model-based recognition system indicate that using explicit lip motion information provides additional performance gains in both applications, and lip motion features prove more valuable in the case of speech-reading application. 相似文献
105.
Mario Lemes Proença Jr. Gilberto Fernandes Jr. Luiz F. Carvalho Marcos V. O. de Assis Joel J. P. C. Rodrigues 《International Journal of Network Management》2016,26(2):76-94
Because of constant growth in proportion and complexity of networks, flow analysis has become an indispensable tool for network management mechanisms. Through this resource, a traffic characterization, called digital signature of network segment using flow analysis (DSNSF), is accomplished. The models used for this purpose are the ant colony optimization metaheuristic, the Holt–Winters forecasting method and the statistical procedure, principal component analysis. The obtained DSNSF by each model is compared with the actual traffic of packets and bits and then subjected to specific evaluations in order to measure its accuracy. The experimental results show that the three methods could achieve good correlation indices and low normalized mean square error values between the DSNSF curve and the real traffic movement, indicating a good adaptability and efficiency in characterizing a network traffic segment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
106.
I. Batista I. Vidal H. M. Lourenço I. Sousa M. L. Nunes 《European Food Research and Technology》1999,210(1):31-33
Clams are widely used in the preparation of several seafood dishes but there are still a few bivalve species which have not been extensively used. Among these species is dog cockle (Glycymeris glycymeris), which is a major by-catch of surf clam (Spisula solida) fishing. However, dog cockle has a low commercial value because its texture is too tough after cooking. This study was initiated to find the best way of tenderising the meat of this species to make it suitable for human consumption. Based on preliminary trials using different tenderising products, a mixture of sodium tripolyphosphate and sodium chloride (3% and 1.5% respectively) was considered the most effective. The optimization of the processing parameters (time and temperature) was done by response surface methodology. According to the sensory analysis, objective texture evaluation and phosphate determinations the optimum conditions for the tenderisation process were an immersion time of 3 h at a temperature of 20 °C. The tenderised meat was used in the preparation of two types of canned products (light brine and a pickling sauce known as "escabeche"), which were evaluated by a taste panel and judged satisfactory. 相似文献
107.
Bit-level systolic arrays for modular multiplication 总被引:4,自引:0,他引:4
This paper presents bit-level cellular arrays implementing Blakley's algorithm for multiplication of twon-bit integers modulo anothern-bit integer. The semi-systolic version uses 3n(n+3) single-bit carry save adders and 2n copies of 3-bit carry look-ahead logic, and computes a pair of binary numbers (C, S) in 3n clock cycles such thatC+S[0, 2N). The carry look-ahead logic is used to estimate the sign of the partial product, which is needed during the reduction process. The final result in the correct range [0,N) can easily be obtained by computingC+S andC+S–N, and selecting the latter if it is positive; otherwise, the former is selected. We construct a localized process dependence graph of this algorithm, and introduce a systolic array containing 3nw simple adder cells. The latency of the systolic array is 6n+w–2, wherew=n/2. The systolic version does not require broadcast and can be used to efficiently compute several modular multiplications in a pipelined fashion, producing a result in every clock cycle. 相似文献
108.
A detailed performance analysis of the least mean square (LMS) algorithm to update each stage of an adaptive Gram-Schmidt processor in interference cancelling adaptive arrays is presented. It is shown that although the number of adaptive weights in the processor is proportional to M 2. the total misadjustment contributed by weight jittering is proportional to only M , where M is the size of the processor. In absolute terms, the weight jittering noises do not accumulate as would be expected, but cancel one another out and decrease in magnitude as the optimal powers become smaller from one processing stage to the next. For optimal performance, the feedback factors used in the individual LMS loops should be normalized so that the amount of misadjustment contributed and the convergence time constant are the same for all processing stages. All the weights belonging to one processing stage must be adjusted in a synchronous manner with the same input vector. This synchronous updating requirement is essential for the cancellation of the jittering noises, although in situations where the weights are adaptively updated in a time-multiplexed manner, it may appear more efficient to update each weight based on the most current inputs 相似文献
109.
Gonçalves SI de Munck JC Verbunt JP Bijma F Heethaar RM Lopes da Silva F 《IEEE transactions on bio-medical engineering》2003,50(6):754-767
In vivo measurements of equivalent resistivities of skull (rho(skull)) and brain (rho(brain)) are performed for six subjects using an electric impedance tomography (EIT)-based method and realistic models for the head. The classical boundary element method (BEM) formulation for EIT is very time consuming. However, the application of the Sherman-Morrison formula reduces the computation time by a factor of 5. Using an optimal point distribution in the BEM model to optimize its accuracy, decreasing systematic errors of numerical origin, is important because cost functions are shallow. Results demonstrate that rho(skull)/rho(brain) is more likely to be within 20 and 50 rather than equal to the commonly accepted value of 80. The variation in rho(brain)(average = 301 omega x cm, SD = 13%) and rho(skull)(average = 12230 omega x cm, SD = 18%) is decreased by half, when compared with the results using the sphere model, showing that the correction for geometry errors is essential to obtain realistic estimations. However, a factor of 2.4 may still exist between values of rho(skull)/rho(brain) corresponding to different subjects. Earlier results show the necessity of calibrating rho(brain) and rho(skull) by measuring them in vivo for each subject, in order to decrease errors associated with the electroencephalogram inverse problem. We show that the proposed method is suited to this goal. 相似文献
110.
Germain M. Benie G.B. Boucher J.-M. Foucher S. Ko Fung Goita K. 《Geoscience and Remote Sensing, IEEE Transactions on》2003,41(8):1765-1772
Radar images can show great variability from pixel to pixel, which is an obstacle to effective processing. This variability, due to speckle created by the radar wave coherence, necessitates the use of more adapted filters. Previous studies have shown that multiresolution wavelet analysis yields better results but produces artefacts due to multiscale decomposition. This paper proposes a method that reduces these effects by introducing the fractal dimension. The resultant filter combines wavelet decomposition and variance change model based on the level of variance estimated by studying the fractal dimension of the image. 相似文献