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For example, the coarse grains by which slab is composed can act as the scattering centers when tested, and form the randomly distributed background noise disturbing the recognition of the flaw echoes.
The number of neurons in the linear layer is less than that in the competitive layer.
Probabilistic neural networks are consisted by two layers of radbas neurons, the number of neurons in the first layer equals with the number of input vectors.
The second layer is competitive layer, its neuron number is the same with that of training specimen classes, each neuron represents a class.
Performance of Pnn network architectures Probabilistic Neural Test set I Test set II Training set Network % % % % % % Number of Correct Error Correct Error Correct Error epochs 32×3 70 30 100 0 100 0 100 Self-Organizing maps.

However, above certain critical velocity, the grains start to move, initially as dunes and at higher velocity as a continuous sand bed [6].
Clearly there exist a number of problems with identifying and defining flow patterns and flow pattern transitions and establishing their range of applicability.
The drag coefficient is a function of particle Reynolds number.
Review of Solid Transport Models: A number of models exist in the literature to estimate particle transport velocity in horizontal pipelines.
SPE Paper Number 27958, August 1994

.% -1.5 -1 -0.5 0 0.5 1 024681012 pH ESA / mPa*m*V-1 HAP:Start-pH-->pH10 HAP: Start-pH-->pH~4 TCPpunched wet gel air dried sample For resorption of the polycrystalline HAP, the specific surface area, grain size and the crystallite size are important.
When concentration increases the pores become smaller but their number were higher in the gel. ¾ Additives in the suspensions (gelatine, ceramic powder and other) cause non-uniform gel structures (wider pore size distributions). 4 wt% HAP 2 wt% HAP+2 wt% TCP 4 wt% nano-HAP Fig. 3: Stereooptical micrographs (bottom view) of punched wet gels as a function of the kind of phosphate powder in the suspension (1 wt % alginate, 1wt % gelatine, 1 M CaCl2) As seen from our general investigations, the consistency of the suspension could be improved.
After the first day of cultivation, we determined a cell number per scaffold of 2.7*104 hMSC, which reveals a seeding efficiency of 34% (Fig. 5a). 0 2 4 6 8 10 12 14 16 18 d1 d27 day of cell culture Cell number [104 cells] 0 1 2 3 4 5 d1 d27 day of cell culture ALP/10 6 cells a: Cell number via lactate dehydrogenase (LDH) activity b: Specific alkaline phosphatase (ALP) activity showing osteogenic differentiation Fig. 5: Osteogenically induced hMSC on alginate-HAP-scaffolds proliferate and differentiate into osteoblasts a: Stretched actin cytoskeleton seen on perimeter indicating cell adhesion (11 of 43) b: Cell nuclei accumulated more distant to the surface (18 of 43) Fig. 4: Osteoblasts on the surface of an alginate scaffold after 27 days of cell culture in ortho presentation of a cLSM stack with 43 images of 83 µm height (blue= nuclei of cells, green= actin cytoskeleton of cells).At day 27, the cell numbers per scaffold was raised to 1.3*105 cells
This nearly 4-fold increase of cell number indicates favorable conditions for cell proliferation.
Higher amounts led to an irregular pore structure and a decrease in pore number.

Yet, a number of biological organisms have evolved solutions to this problem.
For each image in the stacks, three quantities were extracted: The mean pore area, the number of pores, and the porosity ratio calculated as the ratio between the number of pore pixels and the total number of pixels.
At the interface between the porous and the lamellar part the porosity ratio is low with a high number of pores resulting from a large number of minor porosities.
In sample 1, the number of pores in the stone substrate is very large and surpasses the scale chosen to reflect the pore number density of the byssus.
Zlotnikov, Self-similar mesostructure evolution of the growing mollusc shell reminiscent of thermodynamically driven grain growth, Nat.

The rate of material removal also increases as more number of spark strikes on the surface causes more amounts of melting and vapourization of metal from the workpiece surface.The MRR and surface roughness mainly depend on the concentration of the the powder, electrical conductivity of the powder and applied voltage.
Singh et al. [3] have attemted an experiment with aluminium micro-powder on hastelloy steel where the effects of concentration of powder and grain size are investigated on MRR and tool wear rate.
The result from main effect plot shows that the MRR and tool wear rate increase first with increase of powder concentration and grain size first but decreases then.
From the result it is seen that the grain size becomes smaller in Al additive based machining which causes more strength and hardness of the surface.

Elastic deformation of grain Elastic deformation Pile-up Removed (a) Three phases of surface grinding (b) Five phases of cylindrical grinding Fig. 1.
Interactions between single grain and workpiece Along the grinding arc area, from the cut-in to cut-out, the grinding chip thickness is not constant, the undeformed chip thickness gradually increases in the cut-in and then gradually decreases after entering the cut-out, that the heat flow from the cut-in to cut-out will increase and then decreases, in such case, the traditional triangular heat flux distribution model is no longer suitable to predict the temperature in the grinding arc area.
For the assumed quadratic curve heat flux distribution model, the heat flux to the workpiece is given by a 2nd order polynomial function (1) In the case of the quadratic heat flux distribution, the heat source in the grinding arc area can be viewed as the formation of unlimited number of line heat source that first increases and then decreases continuously with the changes in heat intensity q(xi)=Axi2+Bxi.
As we know there are normally two kinds of grinding signals about the temperature signal, background signal and peak signal, where the background corresponds to the temperature on the ground workpiece surface, the peak temperature corresponds to the temperature at grinding point of single grain.

Germination capability of pollen grains was determined by culturing them on medium including boric acid (0，5，10mg/L) and sucrose (50，100，150，200g/L) and BK medium [12].
Hickory pollen grain is small with diameter at 28.4 μm, 3 colporates and smooth surface.
When seed number in single fruit has not obvious difference, differences of fruit endogenous hormone level reflect seed genetic basis difference indirectly.
[11] S.Atefs, “Vigour of wheat pollen grains, ”pp.37-40,1982

- Deflocculating the cement grains, which is obtained by the use of organic products (condensed Formaldehyde and Melamine sulfunate or Naphthalene sulfunate), allows the cement grains in suspension in water to regain their original granularity [10].
This path leads to a significant reduction in the necessary amount of water [11], since high proportion of it, is no more, as in ordinary concrete, trapped in flocks of cement grains, and therefore is not useful for workability
However, considering the cost of additions and additives, this method allows getting the best price and takes account of the rapid loss of workability, hence the interest of a rational method of composition, leading to the control a great number of parameters with a minimum testing.

The waste brick dust was dried at 105 °C to a constant weight and then ground in a ball mill to a grain size of less than 0.3 mm (D10 = 0.885 µm, D50 = 9.600 µm and D90 = 155.416 µm).
Table 1 Tomographic data acquisition parameters Geometric parameters AAAS composite Concrete before loading Concrete after loading X-Ray source–detector distance (mm) 349.9 359.9 359.6 X-Ray source–object distance (mm) 234.0 225.0 240.5 Projection magnification (×) 1.5 1.6 1.5 Pixel size (µm) 50.02 46.76 50.03 X-Ray source parameters Accelerating voltage (kV) 230.0 230.0 230.0 Target current (µA) 190.0 195.0 210.0 Target power (W) 43.7 44.8 48.3 Image data acquisition Exposure time (ms) 240 250 230 Image averaging (×) 4 4 4 Number of projections (–) 2400 1800 1800 Tomographically obtained 3D models of the concrete were compared using a module for digital volume correlation.
From the observation of AAAS composites, it is additionally evident that the cracks pass through the matrix and pores, but not the grains of brick dust, where they copy the interfacial transition zone.
Aside from the applied load during the compressive test, the process of the production of test specimens, the size and distribution of the pores and grains of brick dust, and the possible presence of cracks caused by the maturation of the specimens may all play a role in this behaviour.

It is used in the manufacture of a number of useful alloys such as (Cu-Al), brass and bronze and in sea water applications due to its high resistance to corrosion [6,7].
The Materials The base materials used in the present article are copper (Cu) metal with a grain size (325 mish) and of Indian origin from the manufacture of (CDH) company with a purity of 99.5%, and also a fixed percentage of silicon carbide (SiC) with a grain size (500 mish), originally from Fluka company with 99.5% purity.
As for the support material, (ZrO2, grain size 30 ± 5 nm), German origin from (Changasha Santech Co.), with 99.94% purity was used. 2.