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Occurrence matrix

Milfimeter-to-submillimeter lumps of matrix-rich material are present in many chondrites. Lumps that are mineralogicaUy similar to nearby matrix occurrences are probably pieces of rims or aggregates of interstitial material. However, heavily altered matrix-rich lumps called dark clasts with distinctive mineralogies probably have a different origin (Section 5.7.10). In CH and CB chondrites, aU the matrix material is present as dark clasts there are no matrix rims or interstitial material. [Pg.179]

PAFC cells can last to anywhere between 10,000 and 50,000 hr. However, there are various issues that can reduce the lifetime. The most important is the one related to acid management. Effective humidity control is the key way to control the acid concentration inside that also helps to prevent loss of phosphoric acid. The other aspects of acid management is the uniform distribution of the acid in the matrix. Occurrence of any undesirable distribution of acid can be prevented through a well designed matrix-electrode assembly, along with good distributed contact with the internal/extemal acid reservoirs. [Pg.207]

Note that the low value of the combination Is not the absolute minimum (which would be 4, and is still a possible outcome), just as the high value is not the maximum. The three values (which are calculated by taking the mean of the three lowest values In the matrix etc.) represent equally likely outcomes of the product A B, each with a probability of occurrence of 1/3. [Pg.171]

B-Scan X-Rays Images Segmentation Using Co-Occurrence Matrix. [Pg.231]

Segmentation method based on the analysis by Co-Occurrence Matrix is developed. We try to increase the quality of the obtained results by means of the application of two dimensional (2D) processing. We use Co-Occurrence Matrix for ultrasonic image segmentation. This tool, introduced by Haralick (1), was selected for the present study as several general considerations were favourable ... [Pg.231]

In order to be able to respond fully to the study of the spatial and angular relations between the back-ground of the image and the defects, we opted for the Co-Occurrence Matrix using spatial gray level dependence method. [Pg.232]

The Co-Occurrence Matrix is a function of two variables i and j, the intensities of two pixels, each in E it takes its elements in N (set of natural integers). [Pg.232]

The parameters of this matrix are the image / and the vector d written by [dx, dy] in cartesian coordinates or [ r, 0] in polar coordinates. The number of co-occurrence on the image / of pairs of pixels separated by vector d. The latter pairs have i and j intensities respectively, i.e. [Pg.232]

Finally, each coefficient were standardized by the division of the sum of all coefficients(2). This definition allows also to regard as the co-occurrence matrix as a function of probability distribution, it can be represented by an image of KxK dimensions. [Pg.232]

The given example will allow us to give a small overview on co-occurrence matrix ... [Pg.232]

The choice of the vector d is preponderant for the exploitation of co-occurrence matrix. For each image f several matrix can be calculated, it is imperative to restrain the analysis to significant matrix. [Pg.232]

Lattice models have been studied in mean field approximation, by transfer matrix methods and Monte Carlo simulations. Much interest has focused on the occurrence of a microemulsion. Its location in the phase diagram between the oil-rich and the water-rich phases, its structure and its wetting properties have been explored [76]. Lattice models reproduce the reduction of the surface tension upon adsorption of the amphiphiles and the progression of phase equilibria upon increasmg the amphiphile concentration. Spatially periodic (lamellar) phases are also describable by lattice models. Flowever, the structure of the lattice can interfere with the properties of the periodic structures. [Pg.2380]

In sorjDtion experiments, the weight of sorbed molecules scales as tire square root of tire time, K4 t) ai t if diffusion obeys Pick s second law. Such behaviour is called case I diffusion. For some polymer/penetrant systems, M(t) is proportional to t. This situation is named case II diffusion [, ]. In tliese systems, sorjDtion strongly changes tire mechanical properties of tire polymers and a sharjD front of penetrant advances in tire polymer at a constant speed (figure C2.1.18). Intennediate behaviours between case I and case II have also been found. The occurrence of one mode, or tire otlier, is related to tire time tire polymer matrix needs to accommodate tire stmctural changes induced by tire progression of tire penetrant. [Pg.2537]

Collapse Breccia Pipe Deposits. The primary occurrence of coUapse breccia pipe deposits is in circular, vertical pipes fiUed with down-dropped fragments. Uranium is concentrated in the permeable breccia matrix and in the accurate fracture zones enclosing the pipe. An example of... [Pg.184]

Most commercial cast irons contain 2.5-4% carbon, and it is the occurrence of some of this carbon as free graphite in the matrix that is the characteristic feature of thin material. About 0.8-0.9% carbon is in a bound form as cementite (iron carbide). [Pg.54]

For smaller values of Vj, the behavior of the composite material might not follow Equation (3.84) because there might not be enough fibers to control the matrix elongation. That is, the matrix dominates the composite material and carries the fibers along for the ride. Thus, the fibers would be subjected to high strains with only small loads and would fracture. If all fibers break at the same strain (an occurrence that is quite unlikely from a statistical standpoint), then the composite material will fracture unless the matrix (which occupies only of the representative volume element) can take the entire load imposed on the composite material, that is. [Pg.166]

Each cell in tlie matrix (Table 18.4.2) is assigned a risk ranking as indicated by the letters. In this approach, an A level risk corresponds to a very severe consequence with a high likelihood of occurrence. Action must be taken, and it must be taken promptly. At tlie other end of the scale, a E level risk is of little or no consequence witli a low likelihood of occurrence, and no action is needed or justified. For example, a level C risk might warrant mitigation witli engineering and/or administrative controls or may represent risks tliat are acceptable with controls and procedures. [Pg.519]

The observed reversal in the thermal stability of the copolymer at a critical composition, which appears to be between 30 and 40 mol% of ethylene, may be explained on the basis of the emergence of phase-separation between the nonpolar ethylene and polar vinyl chloride blocks. Although crystallization of the ethylene blocks in the copolymer is only observed when more than 70 mol% ethylene units are present, the possibility of phase-separation occurring at lower contents of ethylene units cannot be excluded. Also, round about the critical copolymer composition, the Tg of the copolymer may be reduced to a level that would facilitate separation between the unlike phases by increased molecular mobility within the polymer matrix. As has been discussed earlier, occurrence of phase-separation in the copolymer would not only make the mechanism of stabilization due... [Pg.334]

But in order for a matrix to have a multiple root, it is necessary that its elements satisfy a certain algebraic relation to have a triple root they must satisfy two relations, and so forth for roots of higher order. Thus, if a matrix is considered as a point in 2-space, only those matrices that lie on a certain algebraic variety have multiple roots. Clearly, if the elements of a matrix are selected at random from any reasonable distribution, the probability that the matrix selected will have multiple roots is zero. Moreover, even if the matrix itself should have, the occurrence of any rounding errors would almost certainly throw the matrix off the variety and displace the roots away from one... [Pg.68]


See other pages where Occurrence matrix is mentioned: [Pg.19]    [Pg.19]    [Pg.45]    [Pg.231]    [Pg.231]    [Pg.231]    [Pg.233]    [Pg.238]    [Pg.180]    [Pg.510]    [Pg.541]    [Pg.136]    [Pg.394]    [Pg.394]    [Pg.22]    [Pg.345]    [Pg.199]    [Pg.280]    [Pg.735]    [Pg.183]    [Pg.176]    [Pg.177]    [Pg.333]    [Pg.442]    [Pg.587]    [Pg.415]    [Pg.423]    [Pg.171]    [Pg.82]    [Pg.43]    [Pg.247]   
See also in sourсe #XX -- [ Pg.530 ]




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