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91.
92.
C57 mice demonstrate progressive age-related hearing loss during the 1st yr, whereas CBA mice lose little sensitivity through 18 mo of age. The acoustic startle response (ASR) was measured to determine behavioral correlates of aging with and without presbycusis. Stimuli were tone pips with frequencies of 4–24 kHz at intensities of 70–200 dB SPL. ASR thresholds increased with age, and startle amplitudes became smaller. Changes in startle parameters were more pronounced in C57 mice, with middle to high frequencies severely affected. Startle latencies at and above ASR threshold increased with age in C57 mice. CBA data indicate that aging has little effect on ASR parameters; the C57 data show that hearing loss is a cogent factor. ASR parameters of C57 mice are altered to a greater extent than expected, on the basis of the elevations of absolute sensory thresholds, particularly for middle frequencies. Both peripheral and central mechanisms may account for the discrepancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
A Broadband Code Division Multiple Access (B-CDMA) technique is presented that will overlay the existing cellular telephone spectrum (825 to 894MHz). The overlay will provide additional capacity to the network while allowing high quality voice and high speed data services to be coexistent with the existing cellular services (AMPS and TDMA). The advantages of using B-CDMA in a fading environment are analyzed. The low level of mutual interference between the existing cellular telephone system and the B-CDMA overlay system is shown.Portions of this paper have been submitted as partial fulfillment of the requirements of the Ph.D. dissertation in electrical engineering at the City College of New York.  相似文献   
94.
HBMO algorithm for calibrating water distribution network of Langarud city   总被引:5,自引:0,他引:5  
In this paper a new meta-heuristic approach based on the nature of honey bees mating has been used for the calibration of a real city in the north of Iran named Langarud. This city has a population of nearly 68,000 people and about 43,000 water consumers. Langarud's area is about 900 km(2). The method was used to determine the Hazen-Williams roughness factor of the main pipes of the town and a correction factor for the nodal demands in the main nodes of the network.  相似文献   
95.
Multimedia Tools and Applications - A variety of approaches have been proposed for addressing different image restoration challenges. Recently, deep generative models were one of the mostly used...  相似文献   
96.
Classifying images is of great importance in machine vision and image analysis applications such as object recognition and face detection. Conventional methods build classifiers based on certain types of image features instead of raw pixels because the dimensionality of raw inputs is often too large. Determining an optimal set of features for a particular task is usually the focus of conventional image classification methods. In this study we propose a Genetic Programming (GP) method by which raw images can be directly fed as the classification inputs. It is named as Two-Tier GP as every classifier evolved by it has two tiers, the other for computing features based on raw pixel input, one for making decisions. Relevant features are expected to be self-constructed by GP along the evolutionary process. This method is compared with feature based image classification by GP and another GP method which also aims to automatically extract image features. Four different classification tasks are used in the comparison, and the results show that the highest accuracies are achieved by Two-Tier GP. Further analysis on the evolved solutions reveals that there are genuine features formulated by the evolved solutions which can classify target images accurately.  相似文献   
97.
Herein, AgCl–Ag2S nanocomposites with dendritic morphology were synthesized via a simple one-pot hydrothermal route for the first time. AgNO3, HCl, and thioacetamide were utilized as starting reagents. The as-prepared AgCl–Ag2S nanocomposites were extensively characterized by techniques such as X-ray diffraction patterns, scanning electron microscopy, energy dispersive X-ray spectroscopy and diffused reflectance UV–visible spectrum. The results showed that the nanoparticles were self-assembled to prepare AgCl–Ag2S nanocomposites with dendritic morphology. The efficiency of AgCl–Ag2S nanocomposites as a photocatalyst for the decolorization of methyl orange (MO) using visible light irradiation has been evaluated. As a result, an enhanced photocatalytic efficiency of AgCl–Ag2S nanocomposites compared to AgCl nanostructures was obtained due to absorption of wider range of light wavelength by AgCl–Ag2S nanocomposites.  相似文献   
98.
Room-temperature synthesis of 2D graphitic materials (2D-GMs) remains an elusive aim, especially with electrochemical means. Here, it is shown that liquid metals render this possible as they offer catalytic activity and an ultrasmooth templating interface that promotes Frank–van der Merwe regime growth, while allowing facile exfoliation due to the absence of interfacial forces as a nonpolar liquid. The 2D-GMs are formed at low onset potential and can be in situ doped depending on the choice of organic precursors and the electrochemical set-up. The materials are tuned to exhibit porous or pinhole-free morphologies and are engineered for their degree of oxidation and number of layers. The proposed liquid-metal-based room-temperature electrochemical route can be expanded to many other 2D materials.  相似文献   
99.
Surface patterning of liquid metals (LMs) is a key processing step for LM-based functional systems. Current patterning methods are substrate specific and largely suffer from undesired imperfections—restricting their widespread applications. Inspired by the universal catechol adhesion chemistry observed in nature, LM inks stabilized by the assembly of a naturally abundant polyphenol, tannic acid, has been developed. The intrinsic adhesive properties of tannic acid containing multiple catechol/gallol groups, allow the inks to be applied to a variety of substrates ranging from flexible to rigid, metallic to plastics and flat to curved, even using a ballpoint pen. This method can be further extended from hand-written texts to complex conductive patterns using an automated setup. In addition, capacitive touch and hazardous heavy metal ion sensors have been patterned, leveraging from the synergistic combination of polyphenols and LMs. Overall, this strategy provides a unique platform to manipulate LMs from hand-written pattern to complex designs onto the substrate of choice, that has remained challenging to achieve otherwise.  相似文献   
100.
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