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31.
Dynamic RSVP protocol 总被引:5,自引:0,他引:5
Geng-Sheng Kuo Po-Chang Ko 《Communications Magazine, IEEE》2003,41(5):130-135
RSVP is a resource reservation setup protocol that can be used by a host to request specific QoS for multicast multimedia flows on the Internet. Multiprotocol label switching (MPLS) architecture also needs RSVP. The fact that the resolutions of the display system used in different receiver nodes might have different, multi-resolution characteristics is supported in the MPEG-4 standard, and the EZW compression algorithm can cease decoding at any point in the bitstream. However, RSVP does not provide a more flexible mechanism. In this article we propose an extension of RSVP to provide the needed mechanism, coined dynamic RSVP (DRSVP), to dynamically adjust reserved resources on nodes without much effort. It provides different video resolutions to different receiver nodes with different needed reserved resources. Therefore, it does not waste precious Internet resources to transmit unnecessary multimedia packets. 相似文献
32.
33.
Chung S.S. Shui-Ming Cheng Lee R.G.-H. Song-Nian Kuo Mong-Song Liang 《Electron Devices, IEEE Transactions on》1997,44(12):2220-2226
This paper reports a simple I-V method for the first time to determine the lateral lightly-doped source/drain (S/D) profiles (n- region) of LDD n-MOSFETs. One interesting result is the direct observation of the reverse-short-channel effect (RSCE). It is observed that S/D n- doping profile is channel length dependent if reverse short-channel effect exists as a result of the interstitial imperfections caused by Oxide Enhanced Diffusion (OED) or S/D implant. Not only the lateral profiles for long-channel devices but also for short-channel devices can be determined. One other practical application of the present method for device drain engineering has been demonstrated with a LATID MOS device drain engineering work. It is convincible that the proposed method is well suited for the characterization and optimization of submicron and deep-submicron MOSFETs in the current ULSI technology 相似文献
34.
The pattern of expression of the simian virus 40 (SV40) T antigen gene and resultant dysplasia were re-examined in a line of transgenic mice in which the T antigen gene was under the control of the SV40 early promoter. We found that T antigen expression in the kidney, and resulting dysplastic lesions, occurred exclusively in the distal convoluted tubules and the ascending limbs of Henle. Epidermal growth factor (EGF) expression in the kidney of normal mice was similarly immunolocalized. The correlation between high EGF immunoreactivity in normal mouse tissues and T antigen expression in the transgenic counterpart was also seen in the choroid plexus epithelium and in the submandibular glands of male mice. T antigen was not found in the submandibular gland of transgenic females. Similarly, EGF was only rarely detected in the normal female submandibular gland. In contrast to the correlation between T antigen expression in the transgenic mice and EGF expression in the corresponding tissues of the normal mice, within the dysplastic lesions of the transgenic mice EGF expression was severely diminished. Adenocarcinomas of the male submandibular gland from another line of transgenic mice that expresses the Int-1 transgene, showed similarly reduced levels of immunostaining for EGF. Thus, reduced expression of EGF might be a general feature of dysplasia and tumorigenesis in those tissues that normally express EGF. 相似文献
35.
Jen-Tsai Kuo 《Microwave Theory and Techniques》1995,43(8):1881-1888
The quasi-TEM spectral domain approach (SDA) is extended to rigorously and efficiently analyze single and multiple coupled microstrip lines of arbitrary metallization thickness. The charge distributions on both the horizontal and vertical conductor surfaces are modeled by global basis functions. This results in a relatively small matrix for accurate determination of the line parameters of coupled thick microstrips. A convergence study is performed for the results of a pair of coupled lines with crucial structural parameters to explore the conditions for obtaining reliable solutions using the technique. Results for thick microstrips are validated through comparison with those from available measurements and another theoretical technique. The soundness of the technique is further demonstrated by looking into the trend of the results obtained by a simplified model in which the structural parameters are pushed, step by step, to the numerical extremities. Variations of circuit parameters of a four-line coupled microstrip structure due to the change of finite metallization thickness are presented and discussed 相似文献
36.
The authors present a low-voltage BiCMOS dynamic minimum circuit using a parallel comparison algorithm for VLSI implementation of fuzzy controllers. Using low-voltage BiCMOS dynamic circuits and a parallel comparison algorithm, a four-4-bit-input minimum circuit designed, based on a 1μm BiCMOS technology, shows a 9.5ns comparison time, which is a ×2.5 improvement in speed as compared to that based on CMOS technology 相似文献
37.
Chin-Te Chen Wen-Li Lin Te-Son Kuo Cheng-Yi Wang 《IEEE transactions on bio-medical engineering》1997,44(7):601-609
The authors discuss a two-model multilayer neural network controller for adaptive control of mean arterial blood pressure (MABP) using sodium nitroprusside. A model with an autoregressive moving average (ARMA), representing the dynamics of the system, and a modified backpropagation training algorithm are used to design the control system to meet specified objectives of design (settling time and undershoot/overshoot) and clinical constraints. The controller is associated with a weighting-determinant unit (WDU) to determine and update the output weighting factor of the parallel two-model neural network for adequate control action and a control-signal modification unit (CMU) to comply with clinical constraints and to suppress the effect of adverse noise and to improve the WDU performance. Extensive computer simulations indicate satisfactory performance and robustness of the proposed controller in the presence of much noise, over the full range of plant parameters, uncertainties, and large variations of parameters 相似文献
38.
C.Y. Kuo E.E. Bergmann 《Photonics Technology Letters, IEEE》1991,3(9):823-831
The authors study the second-order distortion when an erbium-doped fiber amplifier (EDFA) is used to amplify the analog optical AM cable TV (CATV) multiple carrier signal from a directly modulated distributed feedback (DFB) semiconductor laser. Experimentally, it was seen that this second order distortion depends critically on the gain of the EDFA fiber amplifier. The authors attribute this distortion to the interaction between the frequency chirping of the DFB laser and the variable gain with wavelength of the amplifier. The authors describe an electronic predistorter that compensates the nonlinearity produced by the DFB-laser-EDFA combination. As a result, the high power advantage of the EDFA can be fully realized in spite of the potential for second-order distortion in the system.<> 相似文献
39.
The basic structural units of the genome are nucleotides. A single nucleotide polymorphism (SNP) is a mutation at a single nucleotide position. This paper discusses several major problems in SNP data analysis and review some existing solutions in this work. Generally speaking, a rich set of SNP analysis problems are cast in the signal processing framework. Our objective is to offer a state-of-the art review on this topic from a signal processing viewpoint so that researchers in the signal processing field can grasp the important domain knowledge to overcome the barrier between the two fields 相似文献
40.
We examined the ability of opsonized zymosan (OPZ) to stimulate translocation of protein kinase C (PKC) isoforms in human neutrophils. Neutrophils express five PKC isoforms (alpha, betaI, betaII, delta, and zeta), but little is known of their individual roles in neutrophil activation. As determined by immunoblotting, OPZ caused a time-dependent translocation of the predominant PKC isoforms (betaII, delta, and zeta) to neutrophil membranes, with a concomitant loss from the cytosol. Maximal translocation of all three isoforms occurred by 3 min. No PKC immunoreactivity was observed in a crude nuclear fraction, but PKC-delta and -zeta were found in the granule fraction after degranulation (10 min). PKC activity (Ca2+-dependent and -independent) increased 50- and 19-fold, respectively, by 10 min in the granules from OPZ-stimulated cells. Curiously, no immunoreactive cPKC (alpha and beta(I/II)) could be localized in the granule fraction to account for the Ca2+-dependent PKC activity. Localization of PKC isoforms in the neutrophil membranes and granules suggests their involvement in the regulation of functional responses triggered by OPZ. PKC isoform translocation to membranes from OPZ-stimulated cells preceded both p47phox (a cytosolic component of the NADPH oxidase) translocation and NADPH oxidase assembly. The presence of both PKC isoforms and p47phox in the membrane was transient, with the loss of p47phox occurring sooner than either the loss of membrane-associated PKC or that of NADPH oxidase activity. The apparent EC50 values for PKC translocation and NADPH oxidase assembly were similar. These data suggest that PKC isoforms regulate the assembly and activation of NADPH oxidase induced by OPZ. 相似文献