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1.
Adopted in Florence (Italy) on 20 October 2000, the European Landscape Convention is aimed at promoting the protection, management and planning of European landscapes and organising European cooperation on landscape issues. It is the first international treaty to be exclusively concerned with all dimensions of European landscape. It applies to the entire territory of the Parties and relates to natural, urban and peri-urban areas, whether on land, water or sea. It therefore concerns not just remarkable landscapes but also ordinary everyday landscapes and blighted areas. The Convention represents an important contribution to the implementation of the objectives of the Council of Europe: these seek to protect Europeans' quality of life and well-being, taking into account landscape, cultural and natural values. The member states of the Council of Europe signatory to the European Landscape Convention declared their concern to achieve sustainable development based on a balanced and harmonious relationship between social needs, economic activity and the environment. The cultural dimension is also of fundamental importance.  相似文献   
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HDM: A Client/Server/Engine Architecture for Real-Time Web Usage Mining   总被引:1,自引:1,他引:0  
The behavior of the users of a website may change so quickly that it becomes a real challenge to attempt to make predictions according to the frequent patterns coming from the analysis of an access log file. In order to reduce the obsolescence of behavioral patterns as much as possible, the ideal method would provide frequent patterns in real time, making the result immediately available. In this paper, we propose a method for finding frequent behavioral patterns in real time, whatever the number of connected users. Considering how fast frequent behavior patterns may have changed since the time the access log file was analyzed, this result thus provides completely appropriate navigation schemata for predicting user behavior. Based on a distributed heuristic, our method also tackles and provides answers to several problems within the framework of data mining: the discovery of interesting zones (a large number of frequent patterns concentrated over a period of time, or super-frequent patterns), discovering very long sequential patterns and interactive data mining (on-the-fly modification of the minimum support).  相似文献   
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Amorphous silica exhibits a complex mechanical response. The elastic regime is highly nonlinear while plastic flow does not conserve volume, resulting in densification. As a result the quantification of a reliable constitutive equation is a difficult task. We have assessed the potential of micropillar compression testing for the investigation of the micromechanical properties of amorphous silica. We have calculated the response of amorphous silica micropillars as predicted by finite element analysis. The results were compared to preliminary microcompression tests. In the calculations, an advanced constitutive law including plastic response, densification, and strain hardening was used. Special attention was paid to the evaluation of the impact of substrate compliance, pillar misalignment, and friction conditions. We find that amorphous silica is much more amenable than some metals to microcompression experiments due to a comparatively high ratio between yield stress and elastic modulus. The simulations are found to be very consistent with the experimental results. However, full agreement cannot be obtained without allowance for the nonlinear response of amorphous silica in the elastic regime.  相似文献   
5.
The purpose of the experiment was to determine whether diaphragmatic circulation could be compared to other skeletal muscle circulation or whether it has an originality of its own. Diaphragmatic (phrenic and costophrenic arcade arteries), coronary, femoral and cerebral arteries were taken up from anaesthetized pigs, cut into rings and suspended in organ chambers for isometric tension recording. Vasopressin induced a maximal contraction of the femoral artery, no significant changes in tone in cerebral and coronary arteries, and only minimal contraction (30% of the maximum) in diaphragmatic arteries. These results were obtained in a state of basal level of tension or in vessels contracted with prostaglandin F2 alpha. The endothelium did not influence the response in any of the vessels investigated. Norepinephrine induced a contraction in the femoral artery and a relaxation in the coronary artery which was not influenced by the endothelium. Isoproterenol could relax the coronary but not the femoral or the diaphragmatic arteries. The alpha 2-adrenoceptor agonist UK 14304 induced endothelium-dependent relaxation in the diaphragmatic and coronary arteries, but not in the femoral arteries. Phenoxybenzamine unmasked a small alpha-adrenoceptor reserve in the diaphragmatic arteries. These results suggest that diaphragmatic circulation has protective mechanisms in order to preserve a correct supply to the vital respiratory muscle it subserves.  相似文献   
6.
Periodic arrays of anisotropic silver nanoparticles having peculiar optical properties are fabricated at a macroscopic scale. The proposed scalable method is based on temperature‐assisted solid‐state dewetting of a continuous thin layer deposited on a silica substrate patterned by the nanoimprint technique. The resulting nanoparticles are shaped like diamonds and are half‐embedded into the patterned silica. A period‐dependent optimum in film thickness for the quality of spatial organization is found and discussed in terms of thermodynamics and, for the first time, in terms of the role of grains in the dewetting process. The optical properties of the arrays are driven by not only simply the particle shape but also the lattice period and the degree of order. A surface lattice resonance that disperses with the underlying period is evidenced experimentally and confirmed by optical simulations. The opportunity to fabricate and tune such an assembly of plasmonic particles on transparent substrate opens interesting perspectives for not only fundamental photonics but also potential optical applications.  相似文献   
7.
We have carried out uniaxial compression of micron-scale amorphous silica pillars. We have measured load–displacement curves and observed the morphology of the pillars after unloading, providing strong evidence for large plastic deformations. Minor cracking is also observed, with a well-defined pattern. We find that the van Mises stress in compression is comparable to the intrinsic tensile strength of silica. Precise analysis of the deformation of the pillars has been carried out by finite element modeling (FEM) using the constitutive equation determined previously (G. Kermouche et al., Acta Materialia, 56 (2008) 3222), which quantitatively takes into account densification, shear flow and strain hardening. The residual stress distribution we predict by FEM matches the observed crack pattern well. Finally the calculated stress fields in pillar compression and cone indentation are compared. We propose an interpretation of the contrasts in terms of confinement.  相似文献   
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The transport of proton in ion exchange membranes in contact with HCl and H2SO4 solutions is studied. The membranes are the Nafion® 117 cation exchange membrane and, on the other hand, the Selemion® AAV and the Morgane ARA anion exchange membranes. Sorption and water content measurements combined with the radiotracer technique point out the low dissociation degree of the acid present in the membrane phase. This low dissociation leads to the excellent permselectivity towards proton of the Nafion membrane, and it is also the factor which decreases the proton leakage in the two studied anion exchange membranes.  相似文献   
10.
Web usage mining: extracting unexpected periods from web logs   总被引:3,自引:0,他引:3  
Existing Web usage mining techniques are currently based on an arbitrary division of the data (e.g. “one log per month”) or guided by presumed results (e.g. “what is the customers’ behaviour for the period of Christmas purchases?”). These approaches have two main drawbacks. First, they depend on the above-mentioned arbitrary organization of data. Second, they cannot automatically extract “seasonal peaks” from among the stored data. In this paper, we propose a specific data mining process (in particular, to extract frequent behaviour patterns) in order to reveal the densest periods automatically. From the whole set of possible combinations, our method extracts the frequent sequential patterns related to the extracted periods. A period is considered to be dense if it contains at least one frequent sequential pattern for the set of users connected to the website in that period. Our experiments show that the extracted periods are relevant and our approach is able to extract both frequent sequential patterns and the associated dense periods.  相似文献   
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