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81.
Warfarin requirements are lower in the Chinese, but it is not known if this applies to heparin. We investigated the optimal dose for heparin therapy in Chinese patients, and to assess relationship between i.v. heparin dosage and anticoagulation efficacy. One hundred Chinese patients requiring intravenous heparin therapy were given an initial bolus followed by continuous intravenous infusion. The main outcome measures were: (i) Efficacy of anticoagulation assessed by blood coagulation studies (APTT) compared to heparin dosage, (ii) Determinants of dosage variation-age, gender, body weight, height, indication for heparin therapy and number of medications, other disease, and serum albumin level. It was found that the mean therapeutic infusion dose requirement of heparin was 848.7 +/- 274.7 units/h, 79% required a dose of 1000 units/h or less. Heparin dose correlated negatively with age (r = -0.40; p < 0.001) and positively with weight (r = 0.44 p < 0.001) and height (r = 0.49; p < 0.001). Chinese subjects require lower heparin doses (about 800 units/h) than usually recommended for Caucasians (usual dose 1000-1500 units/h). This can be partly explained by the lower body weight in Chinese patients.  相似文献   
82.
83.
A new approach to adaptive fuzzy control: the controller outputerror method   总被引:3,自引:0,他引:3  
The controller output error method (COEM) is introduced and applied to the design of adaptive fuzzy control systems. The method employs a gradient descent algorithm to minimize a cost function which is based on the error at the controller output. This contrasts with more conventional methods which use the error at the plant output. The cost function is minimized by adapting some or all of the parameters of the fuzzy controller. The proposed adaptive fuzzy controller is applied to the adaptive control of a nonlinear plant and is shown to be capable of providing good overall system performance.  相似文献   
84.
The authors develop persistence-of-excitation conditions for the exponential convergence of continuous-time adaptive algorithms. Exponential convergence is important for robustness. Adaptive algorithms without such convergence can behave unacceptably in the presence of modeling inadequacies. Conditions for convergence are usually framed as spanning conditions on a regressor vector involving the output of the unknown system. In this study the authors translate these conditions into ones involving the system input only  相似文献   
85.
The recommended energy dependences of the sensitivity of emergency dosimeters are calculated for different irradiation geometries in the photon energy range of 10 keV–10 MeV. These serve to estimate the levels of radiation for which, according to the NRB-99 standard, either urgent action or action for chronic exposure is necessary. __________ Translated from Izmeritel’naya Tekhnika, No. 11, pp. 52–56, November, 2007.  相似文献   
86.
Ten polymorphic SSR markers of Flammulina velutipes were developed and characterized with FIASCO methods. The polymorphism information content (PIC) ranged from 0.13 to 0.69. This is the first report on development of SSR markers in F. velutipe.  相似文献   
87.
A combination of high‐resolution mapping techniques is developed to probe the homogeneity and defects of mesoscopic perovskite solar cells. Three types of cells using a one‐step infiltration process with methylammonium lead iodide (MAPbI3) or 5‐ammoniumvaleric acid‐MAPbI3 solutions, or two‐step process with MAPbI3 solution are investigated. The correlation between photoluminescence, photocurrent, electroluminescence, and Raman maps gives a detailed understanding of the different infiltration mechanisms, electronic contact at interfaces, and effect on local photocurrent for the cells. The one‐step MAPbI3 cell has very limited infiltration of the perovskite solution which results in poor device performance. High loading of the mesopores of the TiO2 and ZrO2 scaffold is observed when using 5‐ammoniumvaleric acid, but some micrometer‐sized non‐infiltrated areas remain due to dense carbon flakes hindering perovskite infiltration. The two‐step cell has a complex morphology with features having either beneficial or detrimental effects on the local photocurrent. The results not only provide key insights to achieving better infiltration and homogeneity of the perovskite film in mesoporous devices but can also aid further work on planar devices to develop efficient extraction layers. Moreover, this multi‐mapping approach allows the correlation of the local photophysical properties of full perovskite devices, which would be challenging to obtain by other techniques.  相似文献   
88.
A novel technique that uses boundary interpolation to correct geometric distortion and shading artifacts present in images of printed materials is presented. Unlike existing techniques, our algorithm can simultaneously correct a variety of geometric distortions, including skew, fold distortion, binder curl, and combinations of these. In addition, the same interpolation framework can be used to estimate the intrinsic illumination component of the distorted image to correct shading artifacts. We detail our algorithm for geometric and shading correction and demonstrate its usefulness on real-world and synthetic data.  相似文献   
89.
In this paper, we explore the application of a common operator used in systems theory, viz., the delta operator, to formulate a unified theory of multichannel blind deconvolution (MBD) which is valid in both discrete and continuous time domains. Apart from providing a unified treatment of MBD problems, this formulation permits a smooth transition of the demixer from a discrete time domain to a continuous time domain when the sampling rate is high. Furthermore we give a unified treatment of a balanced parameterized state space formulation to solving the MBD problem in both discrete and continuous time domains when the number of states is unknown.  相似文献   
90.
Colloidal metal chalcogenide quantum dots (QDs) have excellent quantum efficiency in light–matter interactions and good device stability. However, QDs have been brought to the forefront as viable building blocks in bottom‐up assembling semiconductor devices, the development of QD solar cell (QDSC) is still confronting considerable challenges compared to other QD technologies due to their low performance under natural sunlight, as a consequence of untapped potential from their quantized density‐of‐state and inorganic natures. This report is designed to address this long‐standing challenge by accessing the feasibility of using QDSC for indoor and concentration PV (CPV) applications. This work finds that above bandgap photon energy irradiation of QD solids can generate high densities of excitons via multi‐photon absorption (MPA), and these excitons are not limited to diffuse by Auger recombination up to 1.5 × 1019 cm?3 densities. Based on these findings, a 19.5% (2000 lux indoor light) and an 11.6% efficiency (1.5 Suns) have been facilely realized from ordinary QDSCs (9.55% under 1 Sun). To further illustrate the potential of the MPA in QDSCs, 21.29% efficiency polymer lens CPVs (4.08 Suns) and viable sensor networks powered by indoor QDSCs matrix have been demonstrated.  相似文献   
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