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101.
S. K. Srivastav C. S. S. Reddy A. Bhattacharya P. R. Reddy 《International journal of remote sensing》2013,34(18):3515-3517
Methods used to infer sea surface temperatures (SSTs) from satellite have traditionally been based on regression-tuned split-window fixed-coefficient algorithms. These can give inaccurate SST results when local atmospheric conditions are significantly different from those encapsulated by the regression averaging. The new generation of SST algorithms attempts to correct for atmospheric variability. These approaches include the R54 transmittance-ratio methods of other workers, and the dynamic water vapour (DWV) correction method of the authors. The relative performances of the various methods are compared by applying each to an ocean and satellite dataset obtained off the west coast of Tasmania, Australia in 1987. We also investigate the performance of the NESDIS operational multi-channel, cross-product, and nonlinear formulas for NOAA-9, -11, -12, and-14 when applied to the same dataset. We find the DWV method gives SST retrievals which have significantly smaller bias errors than those returned by the three transmittance-ratio methods. The best overall performance was returned by the NESDIS multichannel (MCSST) formula for NOAA-9, indicating that in low water vapour loading situations, the standard regression-based algorithms work well. 相似文献
102.
Pramod K. Singh B. Bhattacharya R.K. Nagarale Kang-Wook Kim Hee-Woo Rhee 《Synthetic Metals》2010,160(1-2):139-142
Biopolymer composite membranes based on chitosan doped with an ionic liquid (IL) 1-ethyl 3-methylimidazolium thiocyanate (EMImSCN) have been developed and characterized. The doped ionic liquid films show remarkable enhancement in ionic conductivity (σ). The Fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM) and X-ray diffraction studies (XRD) affirmed the composite nature, good incorporation of ionic liquid and reduction in crystallinity of films, respectively. The interaction between ionic liquid, chitosan and iodide polymer electrolyte matrix was evaluated by cyclic voltammetry. The fabricated dye sensitized solar cell (DSSC) using this new biopolymer electrolyte membranes shows promising performance. 相似文献
103.
Bhattacharya P. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2000,30(5):526-536
The Dempster's rule of combination is a widely used technique to integrate evidence collected from different sources. In this paper, it is shown that the values of certain functions defined on a family of belief structures decrease (by scale factors depending on the degree of conflict) when the belief structures are combined according to the Dempster's rule. Similar results also hold when an arbitrary belief structure is prioritized while computing the combination. Furthermore, the length of the belief-plausibility interval is decreased during a nonhierarchical aggregation of belief structures. Several types of inheritance networks are also proposed each of which allows considerable flexibility in the choice of prioritization 相似文献
104.
Gupta S. Bhattacharya A. Ranga Rao K.S. Chakrabarty A. 《IEEE transactions on instrumentation and measurement》2000,49(1):66-70
This paper presents a simple method for determining the dielectric constant of a solid material. The method consists of measuring the return loss due to a slab of such material inserted into a rectangular waveguide. The dielectric slab presents a discontinuity inside the waveguide, and the electric field at each interface of the slab is described as a summation of weighted sinusoidal basis functions. The scattered magnetic field on either side of the slab is determined using the modal expansion approach. These weights are solved by using the method of moments on the boundary conditions of continuity of the tangential magnetic field at the interfaces. The component of the electric field (scattered) for the dominant TE10 mode can then be determined in terms of these weights, and from this result the reflection coefficient can be theoretically evaluated. A comparison between the experimentally obtained reflection/transmission coefficient and the theoretical values provide a figure for the dielectric constant of the material 相似文献
105.
An integration scheme for a front-end photoreceiver is demonstrated, wherein an identical GaAs-InGaAs-AlGaAs heterostructure is used for realizing a modulated barrier photodiode (MBP) and a doped-channel quasi-MISFET. The detectors exhibit optical gains of 200. The FETs have an extrinsic transconductance of 250 mS/mm, with f f=12 GHz and f max=21 GHz 相似文献
106.
M. C. Bhattacharya M. G. Davies 《International journal for numerical methods in engineering》1987,24(7):1317-1331
The established finite difference equations to estimate one-dimensional transient heat flow in solids are the ‘classical’ form (explicit), and the Crank–Nicolson and ‘pure-implicit’ forms (both implicit). They are all based on finite difference approximation to the Fourier continuity equation. To these are now added three more explicit forms: exponential linear, exponential inverse cosine and polynomial, which are based on exact solutions to the Fourier equation. The performance of each of the six equations is tested against the exact results of a well known step excitations problem (the Groeber model). The tests consist of examining (i) finite difference errors arising from a single implementation of each form at different stages in the transient cooling process, (ii) the errors that accumulate during part or all of the cooling process (both as regards any bias that is introduced, and also a measure of variance) and (iii) the run times in executing the various forms. The nondimensional time step r was treated as the independent variable, and can be made arbitrarily large, by use of a simple time-division procedure (otherwise r < ½ for use with the classical form). It is shown that having regard to both error and run time, the polynomial form appears to be the most efficient estimator. 相似文献
107.
The authors survey high-level approaches to test generation for VLSI circuits, which can significantly reduce test generation time while still providing good fault coverage. High-level approaches view the circuit with less structural detail, that is, from a more abstract viewpoint and often hierarchically. The authors first review some basic circuit and fault models and the two most widely known test-generation algorithms as a basis for comparison between high-level and low-level techniques. The authors then examine the more important high-level approaches, which fall into two broad classes, namely algorithmic and heuristic 相似文献
108.
109.
Deep fat frying characteristics of chickpea flour suspensions 总被引:2,自引:0,他引:2
Keshava K. Bhat & Suvendu Bhattacharya 《International Journal of Food Science & Technology》2001,36(5):499-507
Chickpea ( Cicer arietinum ) (Bengal gram) flour suspensions are widely used in the preparation of oriental traditional snacks and sweets. We investigated the frying characteristics of small and large boondi , a traditional product made by deep fat frying the droplets of chickpea flour suspensions. The rate of water loss during frying was much higher than that of oil uptake. Towards the end of frying, the bulk densities of small and large boondis were similar and remained constant. The analysis of microstructure of the product indicated that there were large pores and vacuoles inside, whereas the outer surface remained fairly smooth with fewer smaller pores. The colour changes during frying were described in terms of tristimulus values (brightness, hue and chroma) and yellowness, of which brightness decreased markedly; the colour of the product changed from bright yellowish orange (raw batter) to dull orange (finished product). 相似文献
110.
System-Level Specification Testing Of Wireless Transceivers 总被引:1,自引:0,他引:1
Halder A. Bhattacharya S. Chatterjee A. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2008,16(3):263-276
This paper presents an efficient system-level manufacturing test methodology for wireless transceiver systems. Conventional system-level testing procedures incur large test times and require the use of multiple test hardware configurations for measuring frequency and modulation-domain performance specifications, e.g., system-gain, nonlinearity, noise-figure, channel power, adjacent-channel power-ratio, error vector magnitude, modulation signal-to-noise ratio and bit error rate. The proposed test methodology addresses these problems by simplifying the test stimulus application and test response capture/analysis procedures. In addition, the number of test hardware configurations needed to measure all the performance specifications is minimized and fewer as well as shorter tests are used to determine all the test specification values of interest. Test accuracy is achieved by optimizing the test stimulus so that the observed response has strong statistical correlation with the target test specification values. Experimental results show significant testing time reduction and was validated on 1.575 GHz and 900 MHz wireless transceiver prototypes. 相似文献