Eddy current imaging,array sensors and flaw reconstruction

Eddy current imaging is widely accepted as a nondestructive testing technique enabling efficient flaw reconstruction based on much richer and comprehensive data sets than the traditional Lissajous patterns obtained from a single scan. In this paper the essential problems encountered during creation and processing of eddy current images are reviewed. The special role of eddy current transducers in creation of eddy current images is emphasized. The main part of the paper deals with formation and solving of eddy current problems which arise when flaw shapes should be reconstructed. An iterative method for reconstruction of 3D flaw images is proposed and discussed. The relation between reconstruction of the 3-D flaw image and the restoration of its 2-D top view is analysed.     

Filtering of some nonlinear diffusions satisfying the general Bene condition

Under some regularity assumptions and the following generalization of the well-known Bene condition [1]:

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, where F(t,z) = g⁻²(t)∫f(t,z)dz, F_t, F_z, F_zz, are partial derivatives of F, we obtain explicit formulas for the unnormalized conditional density q_t(z, x) α Px_t ε dz| y_s, 0 st, where diffusion x_t on R¹ solves x₀ = x, dx_t = [β(t) + α(t)x_t + f(t, x_t] dt + g(t) dw₁, and observation y_t = ∫_o^th(s)x_s ds + ∫_o^t(s) dw_2t, with w = (w₁, w₂) a two-dimensional Wiener process.     

Development of the Cube Component $$ \left( {\left\{ 001 \right\}\left\langle {100} \right\rangle } \right) $$ During Plane Strain Compression of Copper and Its Importance in Recrystallization Nucleation

Metallurgical and Materials Transactions A - The origin of cube texture during recrystallization of medium to high stacking-fault energy FCC metals has been debated for several decades. However,...     

A study on using data clustering for feature extraction to improve the quality of classification

There is a certain belief among data science researchers and enthusiasts alike that clustering can be used to improve classification quality. Insofar as this belief is fairly uncontroversial, it is also very general and therefore produces a lot of confusion around the subject. There are many ways of using clustering in classification and it obviously cannot always improve the quality of predictions, so a question arises, in which scenarios exactly does it help? Since we were unable to find a rigorous study addressing this question, in this paper, we try to shed some light on the concept of using clustering for classification. To do so, we first put forward a framework for incorporating clustering as a method of feature extraction for classification. The framework is generic w.r.t. similarity measures, clustering algorithms, classifiers, and datasets and serves as a platform to answer ten essential questions regarding the studied subject. Each answer is formulated based on a separate experiment on 16 publicly available datasets, followed by an appropriate statistical analysis. After performing the experiments and analyzing the results separately, we discuss them from a global perspective and form general conclusions regarding using clustering as feature extraction for classification.

     

A Bench‐Scale Study of Conditioning Behaviour in Oil Sands Slurries

Proper conditioning of an oil sand/water slurry is essential for the efficient extraction of bitumen. The conditioning process depends on such variables as ore grade, temperature, mixing intensity, mixing time, and water composition. A technique has been developed in which a microscope and video cameras are used to observe a slurry stirred in a glass cell to evaluate, on a comparative basis, the effect of conditioning parameters on bitumen recovery. Several ores and their blends were studied and found to exhibit large differences in their conditioning behaviour. The method offers the capability of diagnosing ore processability problems and optimizing slurry conditioning.     

Verwendung neuer halogenpolyole zur PUR-hartschaumerzeugung mit verminderter brennbarkeit

The usefulness of 3,5-dibromohexane-1,4-diol, 3,5-dichloroheptane-1,4-diol, 3,5-dibromoheptane-1,4-diol, 2-(4,5-dichlorophentyl)propane-1,3-diol and 2-(4,5-dibromopentyl)propane-1,3-diol for the synthesis of rigid polyurethane foams with reduced combustibility was investigated. In addition possibility of utilization of hexane-1,4-diol, heptane-1,4-diol, 2-(pent-4-enyl)propane-1,3-diol and 6-hydroxymethylheptane-1,2,7-triol for the manufacture of foamed polyurethanes is examined too.     

The evaluation of electrolytically polished surfaces

A new method for the evalution of the quality of electropolished suraces is presented. A theoretical analysis was carried out and the results were confirmed by experiment. The relevance of the slope of the surface profile to the evaluation of surface quality was determined. Electropolishing processes affect to a much greater extent the reduction of the standard deviation of the slope than the reduction of the standard deviation ordinates.     

Passive dosimeters — an approach to atmospheric pollutants analysis

The paper presents a review of the passive methods of sampling of inorganic and organic atmospheric pollutants. The importance of these methods, enabling both evaluation of workplace personal exposure and area monitoring, has been discussed. Commercially available personal monitors, as well as devices under further laboratory investigation have been described. Fundamental theoretical equations describing the operation of both passive devices based on diffusion through an air gap to a layer of collective media and passive devices with permeable membranes have been put forward. Presented and discussed herein are papers dealing with the investigation of the applicability of these devices under laboratory and field conditions, as well as with the comparison of passive monitors with active devices (e.g., detector tubes).     

混合法在AZ91D镁合金表面制备的扩散氮化钛涂层的结构及性能

采用钛涂层物理气相沉积法（PVD）和渗氮法结合的混合方法在AZ91D镁合金表面制备扩散氮化钛涂层。涂层由含Ti的氮化物和氧化物的薄的表层区,钛中间区和Ti-Al-Mg型扩散区组成。因涂层改善了合金的耐蚀性能,在铝基亚层上通过氮氧共渗制备涂层时,合金能够得到最好的耐蚀性能。