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In the presence of hundreds or thousands of features, it is common that a large number of features are not informative because they are either irrelevant or redundant with respect to the target concept [2].
Theoretically, the optimal feature selection requires an exponentially large search space (O(2m), where m is the number of features) [1].
As the category information of rare classes is not adequate, only the most common 10 categories are used in our experiments, which are Earn, Acq, Money-fx, Grain, Crude, Trade, Interest, Wheat, Ship and Corn.
We preprocess the data in a formal way: all numbers and stopwords are removed, words are converted into lowercase, word stemming is performed using the Porter stemmer, some noisy words are removed.
The parameter of selected feature number has great influence on the performance comparison.

To prevent the occurrence of seizure, a large number of investigations on the effect of processing conditions on the seizure of titanium were carried out [7, 8, 9].
Table 1 Multi-stage deep drawing conditions of pure titanium blank Stage number 1 2 3 4 5 6 7 8 9 10 Fold pressure / kN 10 0 0 0 0 0 0 0 0 0 Dies / mm Materials Cold tool steel (JIS-SKD11) Hole distance 39 37 35 33 31 29 27 25 23 21 R radius 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 Corner radius 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 Punch / mm Materials Cold tool steel (SKD11), Carbon steel (JIS-S50C) Distance 38 36 34 32 30 28 26 24 22 20 R radius 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 Corner radius 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 Drawing ratio 2.56 1.05 1.06 1.06 1.06 1.09 1.07 1.08 1.09 1.10 Lubricants Molybdenum disulfide Clearance / mm 0.5 - 0.7 0.5 - 0.7 0.5 - 0.7 0.5 - 0.7 0.7 - 0.9 0.9 0.9 0.9 0.9 0.9 Figure 1 Schematic illustration of square cup deep drawing process of titanium blank Table 2 Mechanical properties of pure titanium JIS-grade2 Oxidation treatment Tensile axis to R.D. / o Proof strength / MPa Fracture elongation
The variations of the surface roughness with the stage number for the titanium cups are shown in Fig. 4.
(a) 1st stage (b) 2nd stage (c) 3rd stage Figure 2 Appearances of the drawn cups of pure titanium sheets treated by oxide coating (a) corner at 1st (b) corner at 2nd (c) corner at 3rd Figure 3 The surfaces of the drawn cups Figure 4 Relationship between surface roughness and stage number (a) 1st stage (b) 2nd stage Position relation Figure 5 Distributions of wall thickness strain of the drawn cups by multi-stage deep drawing (a) No heated (b) Heated at 3rd stage Figure 6 Appearances of the drawn cups at 3rd stage after heating at 2nd stage Figure 7 Appearances of the drawn cups with intermediate annealing (a) 1st, 2nd, 3rd, 4th (b) 5th, 6th, 7th, 8th, 9th, 10th Figure 8 Distributions of wall thickness
Kim, Annealing effects on the corrosion resistance of ultrafine-grained pure titanium, Corrosion Science, 89 (2014), 331-337

Laser welding has proven to be a superior process as it provides low average heat input, resulting in a narrow heat-affected zone (HAZ), less segregation of alloys leading to higher corrosion resistance, and less time at annealing temperatures compared to arc and plasma welding to effect diffusion and homogenization of the grain structures.
Unlike in case of fatigue loading of pressure vessels, where the loading is with high range of pressure changes from zero to maximum, i.e. with load asymmetry R = 0, and the number of cycles during the service life is limited, in pipelines the loading is of a high-cycle character with higher load asymmetry given by numerous pressure fluctuations from the mean pressure.
High-cycle fatigue (HCF) resistance was expressed as S-N curves of mostly ten specimens including endurance limit, which was evaluated on the basis of target number of cycles 10 million.
If the specimen did not fail till this target number of cycles, the stress amplitude was considered as the endurance limit provided that another tested specimen loaded with stress amplitude further reduced by 5 – 10 % did not fail either.
The section headings Number of indentation Fig. 7: HV 5 hardness course through laser weld Course of hardness HV 5 from base metal through HAZ and weld metal is documented in Fig. 7.

This difference can be conveniently written as the Hamming distance in the configuration space, , where and are the two spin configurations of the system which subject to the same thermal noise and the same set of random number, N is the number of the total spins on the lattice studied.In theory of codes, the Hamming distance between two strings of bits is the number of different bits.
It can also be a grain film[1].
The NWs form a triangular array with dimension ( is the number of NWs or hexagonal-close packed patterns along the horizontal direction) with lattice constant S [20].

At the same time, the instability of the chemical and mineralogical composition of the initial components causes the enterprises to introduce a number of technological operations to regulate the molding properties of the charge in the technology of building ceramics in the production cycle.
Dispersing the charge leads not only to a decrease in the size of its grains.
Technological parameters of raw The grinding time, hour The content of clay particles, % Forming humidity, % Number of ductility Air shrinkage, % Strength at compression of raw material, MPa Feedstock before dispersion 13.44 7 5 1.5 5.5 1 17.59 8 7 1.9 6.7 2 21.84 9 10 2.2 7.2 3 23.73 10 11 2.4 6.9 In the process of dispersing the bicomponent mixture, brittle fracture of the solid takes place, leading in particular to a change in the state of the surface of the clay particles and drill cuttings themselves.
Accordingly, the maximum plasticity number (equal to 11) was showed by the sample from after 3 hours of treatment.
Drawing the conclusion, it can be assumed that these figures were obtained due to the maximum packaging density of the two-component charge when using the coarse and fine fraction in a ratio of 70 and 30%, respectively, while the size of the fine fraction should be 10 times smaller than the coarse fraction size by increasing the number of ductility and the content of clay particles during processing.

They include requirements to mechanical properties, texture, structure, a number of technological tests and other parameters.
The Study Results Crystallographic texture in metals with hexagonal close packed lattice is an important characteristic that influences metal hardening and anisotropy of a number of its properties.
Texture of titanium tubes largely determines properties of the material, its service properties such as fatigue resistance, a number of technological characteristics such as flattening, bending, expanding, etc.
A number of researchers believe that predominance of radial texture in titanium tubes increases service properties [11].
This is probably because of formation of such a deformation texture which leads to greater hardening and as a result, cracking and fracture of metal caused by rotation of grains to a position that complicates further deformation in the same direction.

As far as preparation processes are concerned, it can be said that bigger number of ppi promote densification while smaller number of ppi inhibit the optimum sintering of samples.
As far as preparation processes are concerned, it can be said that bigger number of ppi promote densification while smaller number of ppi inhibit the optimum sintering of samples.
Densification and grain size are the dominant factors controlling strength, e.g., the substantial increase in strengths of samples corresponded to a parallel increase in density which means a decrease in porosity ratio (stage 1).

According to Di Poala et al. [11] dopants can affect negatively the photoreactivity of TiO2, changing the number of active sites, the type or surface groups, and the acid−base properties.
From the previous studies it is generally believed that an increase in catalyst concentration increases the number of active sites on the photocatalyst surface, which in turn increase the number of hydroxyl and superoxide radicals.
But further increases in the catalyst concentration no longer increases the number of active sites produced by light illumination and, instead, results in agglomeration of catalyst particles and interception of the light by the suspension; hence, part of the catalyst surface becomes unavailable for photon absorption, and the degradation rate decreases.
Li, Effect of operating parameters on microwave assisted photocatalytic degradation of azo dye X-3B with grain TiO2 catalyst, Journal of Molecular Catalysis A: Chemical, 237 (2005) 199-205

Different grain size and anisotropy effects on mechanical properties also have been studied [4].
The relationships between the surface crack length and the dimensionless number of cycles at each stress amplitude for all the three types of holed specimens are shown in Fig. 4.
is defined as the number of cycles when the length is .
The specimens would have sustained very different numbers of fatigue cycles to attain the crack length L, especially when compared with the plain specimen.
It is shown in Fig. 6(a) that the small crack grew slowly at the beginning and it sustained substantial numbers until the length attained 400 μm.

Immobilization efficiency (IE) was calculated using Eq. 1: IE (%) = N x100 No (1) where N is the number of viable immobilized cells released from the immobilization medium (log CFU/g) and No is the initial number of free cells immobilized on agricultural residue (log CFU/ml).
Percentage of immobilization efficiency (IE) defined as percentage of total number of viable cell colonies remains after immobilization over the initial total number of viable cell colonies before immobilization.
Kanellaki: Functionality of freeze-dried L. casei cells immobilized on wheat grains.