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131.
Sentiment analysis is an active research area in today’s era due to the abundance of opinionated data present on online social networks. Semantic detection is a sub-category of sentiment analysis which deals with the identification of sentiment orientation in any text. Many sentiment applications rely on lexicons to supply features to a model. Various machine learning algorithms and sentiment lexicons have been proposed in research in order to improve sentiment categorization. Supervised machine learning algorithms and domain specific sentiment lexicons generally perform better as compared to the unsupervised or semi-supervised domain independent lexicon based approaches. The core hindrance in the application of supervised algorithms or domain specific sentiment lexicons is the unavailability of sentiment labeled training datasets for every domain. On the other hand, the performance of algorithms based on general purpose sentiment lexicons needs improvement. This research is focused on building a general purpose sentiment lexicon in a semi-supervised manner. The proposed lexicon defines word semantics based on Expected Likelihood Estimate Smoothed Odds Ratio that are then incorporated with supervised machine learning based model selection approach. A comprehensive performance comparison verifies the superiority of our proposed approach.  相似文献   
132.
Segmentation of objects from a noisy and complex image is still a challenging task that needs to be addressed. This article proposed a new method to detect and segment nuclei to determine whether they are malignant or not (determination of the region of interest, noise removal, enhance the image, candidate detection is employed on the centroid transform to evaluate the centroid of each object, the level set [LS] is applied to segment the nuclei). The proposed method consists of three main stages: preprocessing, seed detection, and segmentation. Preprocessing stage involves the preparation of the image conditions to ensure that they meet the segmentation requirements. Seed detection detects the seed point to be used in the segmentation stage, which refers to the process of segmenting the nuclei using the LS method. In this research work, 58 H&E breast cancer images from the UCSB Bio‐Segmentation Benchmark dataset are evaluated. The proposed method reveals the high performance and accuracy in comparison to the techniques reported in literature. The experimental results are also harmonized with the ground truth images.  相似文献   
133.
To fabricate SiO2/PDA–SO3H nanocatalyst, a suitable method is designed for the loading of sulfonic acid groups on the surface of polydopamine (PDA)-encapsulated SiO2 nanoparticles. To bridge the gap between heterogeneous and homogeneous catalysis, surface functionalization of silica gel is an elegant procedure. The morphology, structure, and physicochemical features were specified using different analytical techniques including field emission scanning electron microscopy (FESEM), Fourier transformed infrared spectroscopy (FT-IR), high resolution-transmission electron microscopy (HR-TEM), energy dispersive X-ray spectroscopy (EDS), wavelength-dispersive X-ray spectroscopy (WDX), X-ray photoelectron spectroscopy (XPS), and back titration. The SiO2/PDA–SO3H nanoparticles are efficient nanocatalysts for the acetylation of many alcohols, phenols, and amines with acetic anhydride under solvent-free conditions in good to excellent yields. Moreover, the reuse and recovery of the catalyst was shown seven times without detectible loss in activity.

Graphical Abstract

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134.
The 28 GHz Ion Source VENUS (versatile ECR for nuclear science) is back in operation after the superconducting sextupole leads were repaired and a fourth cryocooler was added. VENUS serves as an R&D device to explore the limits of electron cyclotron resonance source performance at 28 GHz with its 10 kW gryotron and optimum magnetic fields and as an ion source to increase the capabilities of the 88-Inch Cyclotron both for nuclear physics research and applications. The development and testing of ovens and sputtering techniques cover a wide range of applications. Recent experiments on bismuth demonstrated stable operation at 300 eμA of Bi(31+), which is in the intensity range of interest for high performance heavy-ion drivers such as FRIB (Facility for Rare Isotope Beams). In addition, the space radiation effects testing program at the cyclotron relies on the production of a cocktail beam with many species produced simultaneously in the ion source and this can be done with a combination of gases, sputter probes, and an oven. These capabilities are being developed with VENUS by adding a low temperature oven, sputter probes, as well as studying the RF coupling into the source.  相似文献   
135.
The present study demonstrates the synthesis and antimicrobial activity of the p-tetranitrocalix[4]arene (3). The microbial activity was determined against a variety of microorganisms, i.e., Gram-positive and Gram-negative bacterial strains such as Staphylococcus aureus ATCC 10231, Streptococcus viridans ATCC 12392, Escherichia coli ATCC 8739, as well as some fungal species including Aspergillus niger ATCC 16404, Aspergillus flavus ATCC 90906, and Candida albicans ATCC 32333. Kirby-Bauer well agar diffusion method was employed for the determination of antimicrobial activity. All the microorganisms were applied to a selective agar medium (Mueller Hinton Agar) for growth. It was observed that compound 3 is considerably effective against selected microorganisms. The MIC values were also evaluated. Thus, from the results it could be deduced that compound 3 may be a valuable addition to the therapeutic index.  相似文献   
136.
137.
ABSTRACT

Behavioral intervention strategies have yet to become successful in the development of initiatives to foster pro-environmental behaviors in buildings. In this paper, we explored the potentials of increasing the effectiveness of requests aiming to promote pro-environmental behaviors by engaging users in a social dialog, given the effects of two possible personas that are more related to the buildings (i.e., building vs. building manager). We tested our hypotheses and evaluated our findings in virtual and physical environments and found similar effects in both environments. Our results showed that social dialog involvement persuaded respondents to perform more pro-environmental actions. However, these effects were significant when the requests were delivered by an agent representing the building. In addition, these strategies were not equally effective across all types of people and their effects varied for people with different characteristics. Our findings provide useful design choices for persuasive technologies aiming to promote pro-environmental behaviors.  相似文献   
138.
Two groups of rats were trained for 50 days on different discriminations in a magazine approach paradigm. One group was trained with a negative patterning schedule and a positive patterning schedule concurrently: they received intermixed trials of A+, B+, AB-, C-, D-, CD+ (A, B, C, and D are four distinct stimuli; the plus sign denotes reinforcement with food, and the minus sign denotes nonreinforcement). The second group of rats was trained with the same four stimuli arranged as compounds and reinforced according to the biconditional schedule AB+, CD+, AC-, and BD-. The first group learned the positive patterning schedule much more quickly than the negative patterning schedule, but they learned the negative patterning schedule more effectively than the second group learned the biconditional schedule. The authors discuss the implications of these findings for models of stimulus representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
139.
The objective of the present study was to explore the impact of health-related messages on the perceived overall healthiness and consumers’ likelihood to buy cereal-based products or non-cereal products containing beneficial compounds from grains, across four European countries. The data were collected from a sample of 2392 members of the public in Finland, Germany, Italy and the UK. The results from a conjoint task with a main effects additive model were reported. In general, the presence of a verbal health claim on foods had positive influence on respondents perception of healthiness and on likelihood to buy the products, whereas the pictorial health claims were found to have a weak influence on the two dependent variables. However, the findings showed that health-related information on food labels differently influenced the healthiness perception and the likelihood to buy the product across the four countries, suggesting that different cultures, traditions, and eating habits have to be taken into account before positioning cereal-based products containing beneficial compounds from grains on the market.  相似文献   
140.
A sample of 947 subjects completed a questionnaire assessing attitudes and beliefs towards the consumption of organic fruits and vegetables. A section of the questionnaire was aimed at assessing the role of trust on perception of risks and benefits associated with pesticides on foods. The subjects tended to hold positive attitudes towards eating fruits and vegetables produced by organic agriculture. The component attitude was found to be a significant predictor of intention to eat organic fruits and vegetables. Intention was found to have a good and significant effect on self-reported consumption. Trust had a positive influence on perceived benefits and a negative influence on perceived risks. Significant relationship was found among perceived benefits and risks associated with pesticides. The results of the cluster analysis indicated the presence of a group of subjects who had less positive attitudes towards organic fruits and vegetables, perceived less risks and more benefits associated with pesticides.  相似文献   
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