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We conclude that the dissociation of iron-boron pairs must be taken into account to explain the light-induced lifetime reduction.
Introduction Light induced degradation (LID) in silicon solar cells has been recognized as a significant cause of minority carrier lifetime reduction during cell operation due to a metastable defect formation under illumination.
A best fit to the experimental data suggested that the generation rate of the (BsO2i)+ defects is controlled by the capture of a majority-carrier hole by the dimer following the capture of a minority-carrier electron and by the Coulomb attraction of the O2i++ to the Bs- atom.
However, other defects based on metallic impurities were proposed to explain the structural identity of the trap responsible for the lifetime reduction [5].
Therefore, we can legitimately assume that the reduction in τeff under illumination is due to the BOi2 formation.

K-means algorithm Theory K-means algorithm is a clustering method in data mining technology.
The peak time data in the following table ,the data of 1-20 is the peak times of ginsenoside Rb1 and ginsenoside Rg1 in radix notoginseng,the data of 21-40 is the ginsenoside Rb1 and ginsenoside Rg1 in American ginseng.
Using the aiNet algorithm on the 40 sample data in Table 1 for simulation.
Putting the forty set of data as the test sample data set, using k-means algorithm to cluster this data .
R. (1992), Fuzzy Models for Pattern Recognition: Methods that Search for Structures in Data, New York: IEEE Press

The data obtained from the experimental analysis is suitable for developing the numerical model for HT distortion.
This mark was used to identify the relative angular position of distortion measurement values, for showing the angular shifts in the distortion data.
Therefore, the distortion data with furnace cooling is treated as that of a heating process just before quenching in a HT process.
This distributed data of distortion are represented by a Weibull plot.
The data shift more on the right side toward higher distortion value in case of 0.4%C-CrMn steel than SUS304.

Generated mainly by the burning of fossil fuels, their reduction can be achieved by changes in the conditions of refining processes, capable of adapting the legal specifications of fuel sulphur and nitrogen, or by treatment of gases exhausted.
About the reduction of NOx indices generated in diesel engines, it is possible to choose the technologies related to fixed bed treatment for removal of nitrogen compounds [2], injection systems much more efficient and improvement of combustion chambers and finally, the treatment of gases exhausted.
The main reactions involved in the process of reduction are described by Equations 1 and 2
(1) (2) As the gases exhausted from diesel contains quantities of NOx greater than 90%, the main reaction that occurs in the SCR (Selective Catalytic Reduction) is described by Equation 1, where ammonia and nitrogen monoxide are in the stoichiometric quantities of 1: 1.
The acceptable error was 5% and the data obtained in the analysis of samples are presented in Table 1.

The Fomichev plug is of characteristic producing equal unit-reduction of wall thickness along its perforation section during seamless tube piercing.
Li Shengzhi in paper [4] showed a 2-D coupled thermal-mechanical simulation of center-crack occurrence during 2-roll rotary rolling process assisted by FE code MSC.SuperForm, and obtained the critical percentage of diameter reduction by comparing the simulation results with experimental data.
Differences between the Fomichev plug and conventional plug The Fomichev plug is of characteristic producing equal unit-reduction of wall thickness aiming to make metal deformation well-distributed along its perforation section, and reduce the drag resistance to longitudinal flow of the metal at the inner surface of the workpiece.
The perforation section generatrix of the novel Fomichev plug discussed in this paper is represented by formula (1): (1) where Rp(x) is plug diameter of the point x in axial coordinate; R(x) is the roll opening at the point x in axial coordinate; SHE is the ideal wall thickness of hollow shell at the intersection between perforating and smoothing section of the plug; Cav is the average reduction ratio of wall thickness.
This kind of plug is somewhat universal, but its flaw is that the wall-thickness reduction of workpiece focuses on one part of the plug in piercing.

In order to improve the understanding deformation behaviors of thermal compressive of ZK30 magnesium alloy, carried out a series of thermal compressive tests with height reduction 60% of specimens were performed at deformation temperature range of 523-673 K, and strain rates range of 0.001-1 s−1 on Gleeble-1500 thermo-mechanical simulator.
The reduction in height is 60% at the end of the thermal compression test.
Comparing these flow curves with one another, thus it can be seen that flow stress decreases markedly with increases in deformation temperature for a particular strain rate, over 62% reduction.
Based on the experimental data, the main points resulted from the present work are presented as follows: (1) At constant strain rate, the deformation behavior of ZK30 magnesium alloy is characterized by the typical dynamic recrystallization and recovery softening mechanisms occur simultaneously.
(2) The parameters of constitutive model in the whole range of deformation conditions were determined by linear fitting test data, such as the apparent activation energy (Q) was estimated to be on average 144.072 KJmol−1, the stress exponents (n) were measured to be 5.386.

In order to simplify the task, the article introduces a new proposal based on theory of elasticity, which have a good accuracy, with minimal experimental data needed.
At first the coefficient ka has been derived from experimental data [2], [3], measured on non-loaded specimens for different types of concrete used in their research.
Once the basic constants were determined the deterioration function has been applied to experimental data at various load levels.
Table 1 and table 2 shows the data adopted from scientific papers published by Schneider and Chen [2], [3], and the data predicted by the theoretical model.
Results of the theoretical model and the experimental data are in good correlation.

Some specimens were then cold drawn with a linear velocity of 1 m/min to 16 % area reduction, and one specimen in 3 passes to 51 % reduction in area.
Drawing was done on a carriage drawing machine at linear speed of 1 m/min with a 16 mm diameter drawing die to 16.4 % reduction in area.
Young’s modulus, yield stress and hardness data are summarised in Table 1.
Table 2 lists also some of our previous data in an attempt to identify the various contributions to overall strengthening of Al and Al-l8.8Cu-6.3%Si-0.7Mg alloy [10].

Currently, data mining in the commercial and industrial areas has been widely used.
Replacing experts, the starting point of DM is to dig out knowledge from massive data.
The dilemma of “massive data, but lack of information” is getting worse.
In essence, data mining, in a given condition, is a process of dimensionality reduction and characterization to the complex problem.
SPRINT: A scalable parallel classifier for data mining.

Based on regression analysis of test data, the formulas for estimating the shrinkage deformation of recycled coarse aggregates concrete are given out, which provide the basis for engineering applications.
With zero growth period, the cement hydration gradually slowed, and pre-hydration resulting hydrate filled pore structure, allowing cement increased compactness, porosity reduction, hydration shrinkage decreases [3].
Because the volume of hardened cement paste is not stable when the relative humidity of external environment is less than 100%, the cement paste will be dehydration, and will be volume reduction [3].
According to experimental data, regression analysis, shrinkage estimation formulas are obtained under different curing conditions in the natural strength grade 100% of recycled coarse aggregate concrete.
Based on regression analysis of test data, the formulas for estimating the shrinkage of recycled coarse aggregate concrete cured in natural environment are given out to provide the basis for engineering applications.