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Abstract

Soft-X-ray radiation passing through capillary waveguides is theoretically analysed by the pulsed-mode method. We consider the optical guiding by straight and tapered waveguides in the spectral range 100–2000 eV. As an example, we calculate the intensity distribution, transmission coefficient and gain factor for the radiation passing through SiO2 waveguides.  相似文献   
23.
Cellular simultaneous recurrent neural network (SRN) has been shown to be a function approximator more powerful than the multilayer perceptron (MLP). This means that the complexity of MLP would be prohibitively large for some problems while SRN could realize the desired mapping with acceptable computational constraints. The speed of training of complex recurrent networks is crucial to their successful application. This work improves the previous results by training the network with extended Kalman filter (EKF). We implemented a generic cellular SRN (CSRN) and applied it for solving two challenging problems: 2-D maze navigation and a subset of the connectedness problem. The speed of convergence has been improved by several orders of magnitude in comparison with the earlier results in the case of maze navigation, and superior generalization has been demonstrated in the case of connectedness. The implications of this improvements are discussed.  相似文献   
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The brain insulin metabolism alteration has been addressed as a pathophysiological factor underlying Alzheimer’s disease (AD). Insulin can be beneficial in AD, but its macro-polypeptide nature negatively influences the chances of reaching the brain. The intranasal (IN) administration of therapeutics in AD suggests improved brain-targeting. Solid lipid nanoparticles (SLNs) and poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) are promising carriers to deliver the IN-administered insulin to the brain due to the enhancement of the drug permeability, which can even be improved by chitosan-coating. In the present study, uncoated and chitosan-coated insulin-loaded SLNs and PLGA NPs were formulated and characterized. The obtained NPs showed desirable physicochemical properties supporting IN applicability. The in vitro investigations revealed increased mucoadhesion, nasal diffusion, and drug release rate of both insulin-loaded nanocarriers over native insulin with the superiority of chitosan-coated SLNs. Cell-line studies on human nasal epithelial and brain endothelial cells proved the safety IN applicability of nanoparticles. Insulin-loaded nanoparticles showed improved insulin permeability through the nasal mucosa, which was promoted by chitosan-coating. However, native insulin exceeded the blood-brain barrier (BBB) permeation compared with nanoparticulate formulations. Encapsulating insulin into chitosan-coated NPs can be beneficial for ensuring structural stability, enhancing nasal absorption, followed by sustained drug release.  相似文献   
25.
Although traditional models have considered the happiness/activities relationship from a reactivity perspective, evidence from recent longitudinal and structural studies indicates that separate propensities contribute to later life levels of happiness and activities. The stabilities obtained with reliable measures of both constructs appear to reflect stable individual differences rather than the effects of levels on environmentally correlated precursors. A review of the evidence suggests that happiness affects the perceived quality of life, and that activity affects functional competence and the remaining lifespan duration. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
Propagation of x rays generated by a small-diameter incoherent source through the capillary waveguide that satisfies the multimode condition is studied with the Fresnel-Kirchhoff diffraction theory. The strong influence of diffraction on the propagation is demonstrated. The diffraction phenomenon is manifested by the appearance of diffraction fringes in both the guide channel and the far-field zone of the capillary output. Experimental data that confirm such behavior of the x-ray radiation is also presented. The results confirm the interference effects recently observed in some experiments on the grazing reflections of x rays in single- and multiple-capillary optics.  相似文献   
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Anastomotic infection is an uncommon but potentially life-threatening complication after lung transplantation. We recently encountered three lung transplant recipients with invasive candidal anastomotic infection. Two patients were admitted with dyspnea and fever, and one asymptomatic infection was detected on surveillance bronchoscopy. All three patients were treated similarly with a combination of intravenous amphotericin B, inhaled amphotericin B, and oral fluconazole. The combination of systemic and inhaled antifungal agents successfully treated all three cases of anastomotic infection.  相似文献   
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Autonomous wireless sensor networks consisting of different types of sensor modalities have been receiving greater attention from researchers due to their versatility and portability. These autonomous sensor networks commonly include passive sensors such as infrared, acoustic, vibration, and magnetic nodes. However, fusion of active sensors in the integrated sensor network, such as Doppler radars, may offer powerful capabilities for many different sensing and classification tasks. In this work, we demonstrate the design and implementation of an autonomous wireless sensor network integrating a Doppler sensor with commercial off-the-shelf components. We investigate the effect of various types of target materials on the measured radar signal as one of the applications of the newly designed radar–mote network. Different types of materials affect the amount of energy reflected back to the source of an electromagnetic wave. We obtain mathematical and simulation models for the reflectivity of different homogeneous non-conducting materials and study the effect of such reflectivity on the classification of targets. We validate our simulation results using real experimental data collected through our autonomous radar–mote sensor network using various types of targets.  相似文献   
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