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Data Mining Technology in Transformer Condition Assessment Principle of Data Mining.
Data preprocessing.
Data preprocessing is a crucial step before data mining, due to the obtained transformer parameters often contain a lot of noisy, incomplete or inaccurate data.
Test data should be dispersed firstly.
The ant colony algorithm is applied for reduction of transformer diagnostic data [6].

Preface: Data is the source of knowledge.
While data mining refers to automatically extracted from the data model.
Including many steps: data mining from large database (or data from other sources); Select the appropriate attributes; Select the appropriate sample strategy; Eliminate data in abnormal data and make up the insufficient part; With proper dimension reduction, transform the data mining process and data model fit or match; Identify whether the resulting knowledge you have will be the result of the information or visualization, and then combined with the existing knowledge.
Statistical analysis of test data, clustering is useful on parameter design and experimental data.
Most of the pattern recognition algorithm and the method of dimension reduction, transform and set has a direct reference significance.

The matrix of correlation data is setup, the elements of which are transformed to dimensionless parameters.
Calculation principle of shear strength reduction Shear strength reduction theory.
The grey relational analysis is a part of grey system theory, make up the deficiencies of using regression analysis, variance analysis and principal component analysis etc in mathematical statistic method which requires a great deal of original data, sample to obey, according to the similarity degree of sequence curves’ geometric shape to judge the factors of change (compare factors) and reference factors’ relevance (in relational express), the bigger the correlation is, the stronger the relevance between compared factor and the influencing factor is.
The specific steps first, define the factors influencing slope stability as comparative column Xi : Xi ={X1, X2, ∧ Xm}t, corresponding slope stability coefficient as a reference column Yi : Xi ={Y1, Y2, ∧ Ym}t, Then dimensionless on each sequence Data make sequence comparable, finally obtained grey relational degree with grey relational matrix [4].
Dimensionless of matrix Due to the large difference in the compare column X and the corresponding reference column Y , we can’t compare directly, the original Data is required to be processed to make comparable, that is make the matrix Dimensionless.

Tight (a-d) and open jointed (e-f) claddings (Author’s collection) Although open joint ventilated façades are increasingly used for thermo-physical rehabilitation of walls, the choice between tight and open jointed systems is not usually made from energy efficiency reasons, due to lack of relevant existing data.
Data acquisition was done in a steady – state heat transfer, when the temperature variation on the hot plate was less than ± 0,1 ºC.
Corresponding to each considered geometry the recording session lasted 10-12 hours and the obtained data resulted by averaging the values of 3 minutes measurements.
Results and discussions Temperature reduction capacity function of the channel thickness.
The values were computed using measured data of air velocity and air temperatures at the inlet and outlet openings [9].

The current CFD models have been validated by the experimental data obtained from the boiler for case study.
These post-combustion control systems are referred to as selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR).
SNCR typically is limited to lower NOX reduction levels but may be the more economical choice depending on the required NOX reduction or the unique project requirements.
In order to obtain accurate and effective temperature data at the location of the SNCR reagent injection points, a 3-D temperature field reconstruction measuring system [19] using 20 detectors was employed to measure the flame temperatures along the furnace height.
All the data offer a solid validation for the numerical simulations and indicate that the mesh and models adopted in the present study are suitable for investigating the three-fuel combustion of the boiler [21].

Introduction Ultrafine particles of many metals have been prepared by various methods, such as photochemical reduction, chemical reduction, chemical liquid deposition, and thermal decomposition.
The scattering data were collected by a position sensitive proportional counter (PSPC).
These data were obtained from the measurement during the stirring of the emulsions, resulting in getting a worse S/N spectrum.
It is expected that the data quality as for S/N will become better without stirring these emulsions.
Reduction with NaBH4 and detailed analysis are in progress.

The part with large area reduction is always accompanied by the appearance of core necking and tensile failure while small area reduction is associated with bad internal quality.
The data that have been sort out after experiment two are given in Table 3.
According to experimental data and related finite element analysis, the research about seeking the forming principle of internal rarefaction of parts revealed that most products with large area reduction have nice internal quality.
Several reasons are given for this phenomenon: (I) for parts with large area reduction, transient axial flow of metal is more than those products with small area reduction.
The boundary confirmed by the internal quality of product The permissible processing area The boundary confirmed by the rotation condition of part The boundary confirmed by the defects about core necking and tension failure Fig.7 Processing Boundary of Limited Area Reduction Conclusions 1) Regression analysis is adopted to deal with the mass experimental data.

An experimental and numerical investigation into forming force reduction in precision gear forging Nicholas J.
As maximum force, along with workpiece size are the two key specifications for industrial forging presses, a reduction in the load required to fully fill a die translates directly to a reduction in the capital investment cost of a production process.
Experimental true stress-plastic strain data is used up to a plastic strain of ε = 0.401, and thereafter the properties are represented using the power-law equation, σ=σy+Kεpn, where: σy=7MPa, K = 96.63 MPa, and n=0.3955.
In order to describe work hardening for strains greater than those obtained in the experiment (ε = 0.401), experimental data was extrapolated to ε = 4 using a power law model with constants: K = 96.63 MPa, and n=0.3955.
A 0.3H sized relief port allows a 45% load reduction, while wasting only 0.3% of the initial billet material.

We find that the capacity of energy conservation and emmision reduction of eastern region is best, the western region is in the middle level, while the central region is not good enough.
Table 1 The meanings of parameters Parameter Explanation the total CO2 emissions of the whole country based on unit GDP energy consumption, (Unit: thousand tons) the total CO2 emissions of province j based on unit GDP energy consumption =44/12, the molar ratio of converting C to CO2 carbon oxidation coefficient of standard coal, we set it as 0.9 the heat transfer coefficient of standard coal, we set it as 29.27 the average carbon content of standard coal, we set it as 24.74 unit GDP energy consumption of standard coal in province j GDP of province (city) j The data of emissions come from the journal China Environment Yearbook, the data of power consumption and conversion coefficient and related data come from China Statistical Yearbook.
Because the data of Tibet is not complicate, we just predict 30 provinces (cities) CO2 emissions.
We used the data of population from China Statistical Yearbook to calculate the per capita CO2 emissions, shown in Figure 2.
In this respect, improving the industrial structure and technical level in high emission intensity areas can promote the emission reduction with a lower cost and more efficient way.

Using the reduction method of the variable precision rough set,the hidden information in power transformer faults data is reduced , and the information which plays a major role in fault classification can be obtained.
The extended model of RST, Variable Precision Rough (VPRS) can overcome this restriction by introducing a probability value [7].Thevalue represents a bound on the conditional probability of a proportion of objects in a condition class which are classified to the same decision.The power transformer fault data was dealed with reduction, redundant information is removed to acquire decision-making rules.
Rough set theory Standard rough set theory.In fault diagnosis,due to the influence of various factors in the actual system, there are some inconsistence between in the test data and the actual value.
Such as in the oil dissolved gas analysis, test data inevitably contain the influence of interference and noise, so,the test data accompany with imprecision and inconsistency.
Pawlak, Rough Sets: Theoretical Aspects of Reasoning About Data,(Kluwer Academic Publishers, USA, 1991)