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1.
Russian Journal of Nondestructive Testing - An Erratum to this paper has been published: https://doi.org/10.1134/S1061830921090114  相似文献   

2.
Russian Journal of Nondestructive Testing - An Erratum to this paper has been published: https://doi.org/10.1134/S1061830921090126  相似文献   

3.
Russian Engineering Research - An Erratum to this paper has been published: https://doi.org/10.3103/S1068798X22110284  相似文献   

4.
Instruments and Experimental Techniques - An Erratum to this paper has been published: https://doi.org/10.1134/S0020441222030204  相似文献   

5.
Purpose: The aim of this study was to evaluate the nanoleakage patterns between dental enamel and reinforced leucite ceramic, bonded with resin luting systems and a flowable composite resin. Materials and Methods: Twelve crowns of bovine incisors were randomly divided into four groups (n = 3) according to the luting procedure: Excite/Variolink II, Clearfil SE Bond/Panavia F, Scotchbond Multi‐Purpose Plus/RelyX ARC, and Single Bond 2/Filtek Z350 Flow. To evaluate the nanoleakage patterns, IPS Empress Esthetic disks (5 mm Ø and 1.2‐mm thick) were bonded to enamel, and, after 24 h, the specimens were immersed in a 50% (w/v) solution of silver nitrate (24 h), fixed, dehydrated, and processed scanning electron microscopy (SEM). Results: None nanoleakage on interface of the groups that Single Bond 2 followed by the flowable composite were used. The highest percentage of nanoleakage was shown by the Excite/Variolink II protocol. Also, in all conditions tested, none silver nitrate uptake was observed between the leucite‐reinforced ceramic and the resin luting cement. Conclusions: The use of a two‐step etch‐and‐rinse adhesive with flowable composite was able to promote an adequate seal of the bond interface at the enamel. Moreover, the conventional dual‐cured resin cements associated with simplified and dual‐cured adhesives tested are also indicated to bond thin ceramics to enamel, since all presented low silver nitrate uptake. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

6.
This paper aims at presenting a technique to replace the moving load by an equivalent moving finite element so that both the transverse and the longitudinal inertial effects due to the moving mass may easily be taken into account simultaneously. Where the mass, damping and stiffness matrices of the moving finite element are determined by the transverse () inertia force, Coriolis force and centrifugal force of the moving mass, respectively. From the numerical examples illustrated, it has been found that, in addition to the conventional transverse () responses, the inertial effects of the moving load also affect the longitudinal () responses of the portal-frame structure significantly.  相似文献   

7.
The objective of this study was to compare expert versus fractal analysis as new methods to evaluate branchial lamellar pathology in European sea bass Dicentrarchus labrax (Linnaeus, 1758) experimentally exposed to cadmium and to terbuthylazine. In particular, guided expert quantitative and fractal analysis were performed on selected images from semithin sections to test possible differences according to exposure class (unexposed, cadmium exposed, or terbuthylazine exposed) and the discrimination power of the two methods. With respect to guided expert quantitative analysis, the following elementary pathological features were assessed according to pre‐determined cover classes: ‘epithelial lifting’, ‘epithelial shrinkage’, ‘epithelial swelling’, ‘pillar cells coarctation’, ‘pillar cells detachment’, ‘channels fusion’, ‘chloride cells swelling’ and ‘chloride cells invasion’. Considering fractal analysis, DB (box dimension), DM (mass dimension), (mean fractal dimension) as fractal dimensions and lacunarity from DM and scan types were calculated both from the outlined and skeletonized (one pixel wide lines) images. Despite significant differences among experimental classes, only expert analysis provided good discrimination with correct classification of 91.7 % of the original cases, and of 87.5 % of the cross‐validated cases, with a sensitivity of 95.45 % and 91.3 %, respectively, and a specificity of 75 % in both cases. Guided expert quantitative analysis appears to be a reliable method to objectively characterize fish gill pathology and may represent a powerful tool in environmental biomonitoring to ensure proper standardization and reproducibility. Though fractal analysis did not equal the discrimination power of the expert method, it certainly warrants further study to evaluate local variations in complexity or possible multiple scaling rules.  相似文献   

8.
9.
Russian Journal of Nondestructive Testing - An Erratum to this paper has been published: https://doi.org/10.1134/S1061830921310016  相似文献   

10.
Dentin irradiation with erbium lasers has been reported to alter the composite resin bond to this treated surface. There is still a lack of studies reporting the effect of erbium lasers on dentin organic content and elucidating how laser treatment could interfere in the quality of the resin-dentin interface. This study aimed to evaluate the effect of erbium laser irradiation on dentin morphology and microtensile bond strength (μTBS) of an adhesive to dentin. Seventy-two dentin disks were divided into nine groups (n = 8): G1-Control (600-grit SiC paper); Er:YAG groups: G2- 250 mJ/4 Hz; G3- 200 mJ/4 Hz; G4- 180 mJ/10 Hz; G5- 160 mJ/10 Hz; Er,Cr:YSGG groups: G6- 2 W/20 Hz; G7- 2.5 W/20 Hz; G8- 3 W/20 Hz; G9- 4 W/20 Hz. Specimens were processed for cross-sectional analysis by scanning electron microscopy (SEM) (n = 3), transmission electron microscopy (TEM) (n = 2), and adhesive interface (n = 3). Forty-five dentin samples (n = 5) were restored and submitted to μTBS testing. ANOVA (α = 5%) revealed that G1 presented the highest μTBS values and irradiated groups did not differ from each other. TEM micrographs showed a superficial layer of denatured collagen fibrils. For SEM micrographs, it was possible to verify the laser effects extending to dentin subsurface presenting a rough aspect. Cross-sectional dentin micrographs of this hybridized surface revealed a pattern of modified tags with ringlike structures around it. This in vitro study showed that erbium laser irradiation interacts with the dental hard tissue resulting in a specific morphological pattern of dentin and collagen fibrils that negatively affected the bond strength to composite resin.  相似文献   

11.
This paper depicts the relationship among the loss function, process capability indices and control charts to establish goal control limits by extending the target costing concept. The specification limits derived from the reflected normal loss function is linked through the C pm value, computed either directly from the raw data or given by management or engineers, to conventional control charts to obtain goal control limits. The target value can be taken into consideration directly. The advantages of applying the target costing philosophy are also discussed. This paper explains, from a quantitative approach, that reducing process variation is not enough to solve quality problems. In fact, reducing process variation should be used along with bringing the process mean to the target value.A list of symbols K: The maximum-loss parameter in the reflected normal loss function - : The shape parameter in the reflected normal loss function, /4 - T: The target value - : The distance from the target value to the point where K first occurs (tolerance or specification limit) - E(L(y)): The expected loss associated with the reflected normal loss function - : The average value (mean) of a population - : The standard deviation of a population - T : The standard deviation from the target value of a population - : The estimated standard deviation of - : The new process standard deviation when 2 are applied - n: The sample size of the subgroup - d 2: The parameter used to estimate , determined by n - D 4, D 3, and A 2: The parameters in and R control charts, determined by n - c 4: the parameter used to estimate , determined by n - B 4, B 3, and A 3: The parameters in and S control charts, determined by n - L(y): The general loss function - L 1(y): The general loss function when the quality improvement is implemented - h: The parameter used to determine L 1(y), where L 1(y)=hK - f(y): The probability density function  相似文献   

12.
Artificial intelligence is nowadays used for cell detection and classification in optical microscopy during post-acquisition analysis. The microscopes are now fully automated and next expected to be smart by making acquisition decisions based on the images. It calls for analysing them on the fly. Biology further imposes training on a reduced data set due to cost and time to prepare the samples and have the data sets annotated by experts. We propose a real-time image processing compliant with these specifications by balancing accurate detection and execution performance. We characterised the images using a generic, high-dimensional feature extractor. We then classified the images using machine learning to understand the contribution of each feature in decision and execution time. We found that the non-linear-classifier random forests outperformed Fisher's linear discriminant. More importantly, the most discriminant and time-consuming features could be excluded without significant accuracy loss, offering a substantial gain in execution time. It suggests a feature-group redundancy likely related to the biology of the observed cells. We offer a method to select fast and discriminant features. In our assay, a 79.6 2.4% accurate classification of a cell took 68.7 3.5 ms (mean SD, 5-fold cross-validation nested in 10 bootstrap repeats), corresponding to 14 cells per second, dispatched into eight phases of the cell cycle, using 12 feature groups and operating a consumer market ARM-based embedded system. A simple neural network offered similar performances paving the way to faster training and classification, using parallel execution on a general-purpose graphic processing unit. Finally, this strategy is also usable for deep neural networks paving the way to optimizing these algorithms for smart microscopy.  相似文献   

13.
The bar code is one of the identification technologies used more successfully in the world. This technology was first developed as the second half of the twentieth century and quickly achieved acceptance in both industry and commerce. In this paper studies are discussed on the design, development and printing of one-dimensional barcodes of the symbologies Code 39 and Interleaved 2 of 5. There are also discussed techniques for recovering the information encoded in the bar code, which can be extended to other symbologies. The purpose of the paper is the development of an open solution with the objective to make the decoding of barcodes using computer vision techniques possible, which will be divided into four basic stages: acquisition, pre-processing, processing and presentation of results. Practical tests conducted with samples show satisfactory results, validating the operating principles of the elements involved. The proposed objective was achieved and practical tests validated the operating principles of the elements addressed by providing contribution to that segment decoding barcodes.  相似文献   

14.
The influences due to several AVIs (airfoil-vortex interactions) are studied by using a two-dimensional CFD (computational fluid dynamics) method. The primary goal of this effort is to assess the variation of vortex center location and vortex circulation associated with sequential AVI toward an improvement of the hybrid method of CFD and prescribed wake model, which closely relates to predicting the BVI (blade-vortex interaction) noise radiated from a helicopter rotor. The representative of sequential AVI is performed by single vortex and two airfoils. Investigations with respect to vortex center location and vortex circulation after AVIs have been made by varying the miss-distance, which is the vertical distance between the airfoil leading edge and the vortex center. Correlations between miss-distance and vorticity field show that there exists complicated vortex wake flow with several vortices newly induced in 1st AVI. The pressure fluctuation amplitude clarifies that the intensity in 2nd AV1 is significantly low compared to the intensity in 1st AVI due to the influence of vortex dissipation. Simulations turned out to modify the vortex center location represented by the hybrid method using an offset value for a streamwise direction and to dissipate the vortex circulation for improving the accuracy of BVI noise prediction.  相似文献   

15.
16.
Creep deformation under constant load leads to rupture when the polymer chains can no longer separate and accommodate the load. This fracture phenomenon is investigated interferometrically. The creep behaviour of as‐spun isotactic Polypropylene (iPP) fibres is studied at different stresses, different initial lengths and different radii. The creep rate, which defines the velocity of the creep deformation and the dimensional stability of the material, is studied. The failure time and stress of iPP due to creep process is determined. The necking deformation was in situ detected during creep process. The mean refractive indices (nP and) profiles of iPP fibres were determined at different positions along the fibre axis before and after necking. The relation between the creep behaviour and different optical and structural parameters is investigated. Microinterferograms are given for illustration.  相似文献   

17.
A closed-form solution for upper and lower bounds (‘dual bounds’) to a slow indentation of rigid ball (under increasing normal load) into rigid plastic solids are presented. The solutions enlarge the theoretical background to the familiar Brinell hardness tests used in assessing strength of materials and add few new features.The new features are mainly: (i) constructing a lower-bound solution to ball indentation, (ii) a closed-form estimation of the dual bounds with any prescribed frictional shear along the indenter/solid contact, (iii) providing dual bounds to two different situations of the material response: (a) the removed material is falling off from the bulk (akin to indentation into brittle-like materials) and (b) the removed material is piled up along the indenter face (akin to indentation into ductile-like materials).The dual bound solutions of the indenting mean ball pressure for both material cases seem to capture properly well the material constrain to local plastic indentation and the effect of the interfacial friction. Having both bounds simultaneously, despite their unavoidable deviation, provide much more informative results than a single bound.Comparisons between the suggested bounding analysis and experiments (taken from Tabor [Tabor D. Hardness of Metals. Oxford: Clarendon Press; 1951], Johnson [Johnson KL. Contact mechanics. Cambridge: Cambridge University Press; 1985 (new edition, 2001)] and others), numerical FEM solutions (Mesarovic and Fleck [Mesarovic SDj, Fleck N. Spherical indentation of elastic-plastic solids. Proceedings of Royal Society of London 1999; A455: 2707–28] and others) and some self-made measurements are all favorable.  相似文献   

18.
Russian Engineering Research - An Erratum to this paper has been published: https://doi.org/10.3103/S1068798X21050270  相似文献   

19.
Russian Engineering Research - An Erratum to this paper has been published: https://doi.org/10.3103/S1068798X22100355  相似文献   

20.
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