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1.
Test Case Generation as an AI Planning Problem   总被引:6,自引:0,他引:6  
While Artificial Intelligence techniques have been applied to a variety of software engineering applications, the area of automated software testing remains largely unexplored. Yet, test cases for certain types of systems (e.g., those with command language interfaces and transaction based systems) are similar to plans. We have exploited this similarity by constructing an automated test case generator with an AI planning system at its core. We compared the functionality and output of two systems, one based on Software Engineering techniques and the other on planning, for a real application: the StorageTek robot tape library command language. From this, we showed that AI planning is a viable technique for test case generation and that the two approaches are complementary in their capabilities.  相似文献   
2.
The reversal of humic matter-induced inhibition of callus growth and metabolism by 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in Pinus laricio. Two forest humic fractions (relative molecular mass (Mr) > 3500), derived from soil under Fagus sylvatica (Fs) and Abies alba (Aa) plantation, were used. Pinus laricio callus was grown for a subculture period (4 weeks) on Basal Murashige and Skoog (MS) medium plus forest humic matters (Fs or Aa), at a concentration of 1 mg C/l, and then was transferred, for an additional four weeks, to a MS medium culture without humic matter, but with different hormones: indole-3-acetic acid (IAA, 2 mg/1) or 2,4-dichlorophenoxyacetic acid (2,4-D, 0.5 mg/1) and/or 6-benzylaminopurine (BAP, 0.25 mg/1). Growth of calluse, glucose, fructose, and sucrose contents, and activities of soluble and bound invertases, glucokinase, phosphoglucose isomerase, aldolase, and pyruvate kinase were monitored. The results show a negative effect of humic fractions on callus growth, due to decreased utilization of glucose and fructose, and decreased activities of glycolytic enzymes. The effects are reversible. Substitution of humic fractions with 2,4-D+BAP or 2,4-D is followed by an increase of glycolytic enzyme activities and, consequently, by the utilization of glucose and fructose that induces a restart of growth. In contrast, the inhibitory effects of humic fractions persist when they are substituted with BAP alone, indicating that only the auxin 2,4-D is capable of reversing the negative effects. A possible competitive action on the auxin-binding site between 2,4-D and the chemical structures in the forest humic fractions is suggested.  相似文献   
3.
4.
The sensitivity of COSMO-SkyMed (CSK) incoherent dual-polarimetric synthetic aperture radar (SAR) data to the rice growth cycle is investigated here. State-of-the-art scattering models are used, together with a time series of 24 CSK SAR images collected in Mekong Delta, Vietnam in 2014, to interpret the behaviour of multi-polarization features with respect to the different phenological stages that characterize rice growth. Experimental results show the multi-polarization features sensitivity with respect to rice growth cycle and witness that a joint use of the co-polarized channels (i.e. co-polarized ratio or correlation between co-polarized channels) allows identifying scattering behaviours that are compatible with four stages of the rice growth cycle.  相似文献   
5.
Steady laminar free convection from a horizontal elliptic cylinder set in unbounded space is studied numerically under the assumption of uniform surface temperature. A specifically developed computer-code based on the SIMPLE-C algorithm is used for the solution of the mass, momentum and energy transfer governing equations. Simulations are performed for ratios between the minor and major axes of the elliptic cross-section of the cylinder in the range between 0.05 and 0.98, inclination angles of the major axis of the elliptic cross-section with respect to gravity in the range between 0° and 90°, Rayleigh numbers based on the major axis of the elliptic cross-section in the range between 10 and 107, and Prandtl numbers in the range between 0.7 and 700. It is found that the heat transfer rate increases with increasing the Rayleigh and Prandtl numbers, while decreases with increasing the orientation angle of the cross-section of the cylinder, i.e., passing from the slender to the blunt configuration. In addition, a noteworthy fact is that in most cases the amount of heat exchanged at the cylinder surface has a peak at an optimum axis ratio which is practically independent of the Prandtl number, while may either increase or decrease with increasing the Rayleigh number depending on whether the orientation angle of the tube is above or below a critical value of approximately 67.5°. Dimensionless correlating equations are proposed both for the optimum axis ratio for maximum heat transfer and for the heat transfer rate from the cylinder surface to the undisturbed surrounding fluid reservoir.  相似文献   
6.
Laminar natural convection heat transfer inside fluid-filled, tilted square cavities cooled at one side and partially heated at the opposite side, is studied numerically. A computational code based on the SIMPLE-C algorithm is used for the solution of the system of mass, momentum, and energy transfer equations. Simulations are performed for a complete range of heater sizes and locations, Rayleigh numbers based on the side of the cavity from 103 to 107, Prandtl numbers from 0.7 to 700, and tilting angles of the enclosure from ?75° to +75°, where negative angles correspond to configurations with the heater facing downwards. It is found that the heat transfer rate increases with increasing the Rayleigh and Prandtl numbers, and the size of the heater. In addition, for negative inclinations of the enclosure the amount of heat exchanged decreases with increasing the tilting angle, while for positive inclinations the heat transfer rate either increases or decreases according as the heater is located toward the top or the bottom of the cavity. Finally, as far as the heater location is specifically concerned, the heat transfer performance has a peak for intermediate positions, the higher are the Rayleigh and Prandtl numbers, as well as the tilting angle for positive inclinations, the closer to the bottom of the cavity is the optimum heater location for maximum heat removal.  相似文献   
7.
Nuclear-magnetic-resonance (NMR) profiling of exhaled breath condensate (EBC) provides insights into the pathophysiology of bronchiectasis by identifying specific biomarkers. We evaluated whether NMR-based metabolomics discriminates the EBC-derived metabolic phenotypes (“metabotypes”) of 41 patients with non-cystic fibrosis (nCF) bronchiectasis of various etiology [24 subjects with Primary Ciliary Dyskinesia (PCD); 17 patients with bronchiectasis not associated with PCD (nCF/nPCD)], who were compared to 17 healthy subjects (HS). NMR was used for EBC profiling, and Orthogonal Projections to Latent Structures with partial least-squares discriminant analysis (OPLS-DA) was used as a classifier. The results were validated by using the EBC from 17 PCD patients not included in the primary analysis. Different statistical models were built, which compared nCF/nPCD and HS, PCD and HS, all classes (nCF/nPCD-PCD-HS), and, finally, PCD and nCF/nPCD. In the PCD-nCF/nPCD model, four statistically significant metabolites were able to discriminate between the two groups, with only a minor reduction of the quality parameters. In particular, for nCF/nPCD, acetone/acetoin and methanol increased by 21% and 18%, respectively. In PCD patients, ethanol and lactate increased by 25% and 28%, respectively. They are all related to lung inflammation as methanol is found in the exhaled breath of lung cancer patients, acetone/acetoin produce toxic ROS that damage lung tissue in CF, and lactate is observed in acute inflammation. Interestingly, a high concentration of ethanol hampers cilia beating and can be associated with the genetic defect of PCD. Model validation with 17 PCD samples not included in the primary analysis correctly predicted all samples. Our results indicate that NMR of EBC discriminates nCF/nPCD and PCD bronchiectasis patients from HS, and patients with nCF/nPCD from those with PCD. The metabolites responsible for between-group separation identified specific metabotypes, which characterize bronchiectasis of a different etiology.  相似文献   
8.
Avocado industry produces enormous by-products and represents an important source of raw material in food and non-food applications. This review aims to focus the attention on the valorisation of avocado wastes recycling to produce different materials with important industrial and environmental impacts. In fact, peels and seeds can be reused in food and cosmetic fields due to the presence of bioactive ingredients such as polyphenols; thanks to their antioxidant and antinflammatory activities. In addition, both peels and seeds can be reused in the production of carbonaceous materials with important consequences for environmental pollution in the removal of contaminants from water. Interesting applications of avocado wastes in photocatalysis and biofuel production are also discussed. All the utilisations attest the great potential of recycling avocado by-products, a little known resource.  相似文献   
9.
The beneficial effects on peak selectivity and resolution of conducting liquid chromatography (LC) at elevated temperature (e.g., 30-80 degrees C) are generally well-known; however, its importance for peptide recovery is not nearly as well recognized. This report demonstrates that microLC analysis of membrane proteomic samples significantly benefits from the application of heat. Enriched membrane and membrane-embedded peptides (the latter obtained by membrane shaving) were analyzed by microLC-tandem mass spectrometry (MS/MS) from 20 to 60 degrees C using a standard reversed-phase material. Maximal protein and hydrophobic peptide recovery was obtained at 60 degrees C. The membrane-shaving method employed, a recently optimized version of the high pH/proteinase K protocol, provided significant integral membrane protein enrichment: 98% of identified proteins were predicted to have at least one transmembrane domain (87% to have at least three), and 68% of peptides were predicted to contain transmembrane segments. Analysis of this highly enriched sample at elevated temperature increased protein identifications by 400%, and peptide identifications by 500%, as compared to room-temperature separation. Given that most microLC-MS/MS analyses are currently conducted at room temperature, the findings described herein should be of considerable value for improving the comprehensive study of integral membrane proteins.  相似文献   
10.
BACKGROUND: The present article reports the anthocyanin content in the berry skin and wine of the Italian red grape cultivar Aglianico (clone VCR11 grafted onto 1103 Paulsen), one of the most ancient vines and famous for its deep‐red colour. Anthocyanins were extracted from frozen berry skin in an acidified methanol solution. The extraction mixtures, monitored for 120 h, were analysed by high‐performance liquid chromatography. RESULTS: The extraction from berry skin of delphinidin, petunidin and malvidin appeared to be a time‐independent process, whereas the concentration of peonidin increased linearly with time. Peonidin‐O‐acetyl‐glucoside was transferred from skin more slowly than petunidin‐O‐acetyl‐glucoside and malvidin‐O‐acetyl‐glucoside. The anthocyanin composition of the resulting wine showed that the total anthocyanin content was about one‐tenth of the corresponding berry skin content. The ratio acetyl/coumaroyl anthocyanins in the wine was sharply higher than the value in berry skin (0.85 and 0.10, respectively), indicating an enrichment of acetyl derivatives in the wine. CONCLUSION: Levels of single anthocyanins in wine were not always correlated with those detected in grapes, as they were affected by winemaking. The high values of some anthocyanins in Aglianico wine could ameliorate its quality, increasing the chromatic properties, aging stability and product acceptance. Copyright © 2011 Society of Chemical Industry  相似文献   
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