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Complex mechanical and electrical equipment contains a large amount of data with the implicit information. According to the development of PHM (Prognostics and Health Management) technology at home and abroad, and the wide application prospects of data driving methods, the overall framework of data driven PHM system for complex electromechanical equipment was designed. The data driven PHM implementation process of the complex mechanical and electrical equipment was described step by step, which provides important theoretical significance and application value for the PHM research of the complex mechanical and electrical equipment. Finally, the development trend and research challenges of data driven PHM method were analyzed.

In this paper, a kind of data driven PHM system architecture based on data driven is came up; then a field data acquisition scheme which is very important in PHM system is presented; with a case, the block diagram of the scheme realization, which includes OPC server software configurations, and client software development process is shown. In this case, the data acquisition software has been developed by using the C #language and the local database and the data center database has been created to save data. The data acquisition software can read data from the PLC and save data to the database, which provides a stable and accurate data source for PHM system and has good stability and compatibility.

In a recent failure analysis case of relay, the pure Pb whisker growth is found on the Pb60Sn40 solder layer on the Au coating of the spring leaf. The content analysis by the EDX shows that the Pb whisker grows from the Pb grain, which is surrounded by the AuSn intermetallic compound. It is thought that the elastic force of the spring leaf and the compressive stress from the intermetallic compound contributes to the Pb whisker growth, and the later factor is confirmed by the FIB (focused ion beam) result. Besides, the statistics result shows that the longer Pb whisker corresponds to the thicker Au coating, which could be explained by the effect of Au: forming AuSn intermetallic compound and Pb rich area. This work enriches our understandings on the metal whisker growth and consequently potential failure mode of SnPb solder.

Magnetic flux leakage (MFL) testing is widely used to inspect and characterize defects in storage tank floors, pipelines and other structures. In this paper, magnetic flux leakage testing technology is applied to the horizontal product oil underground tank wall inspection. The artificial defects were prefabricated on the tank wall such as corrosion pits, grooving and other artificial defects to simulate the corrosion, cracks and other actual defects in actual working conditions. The experimental research of the mutual influence between magnetic flux leakage and defects’ parameters were carried out, such as the depth and width of cracks, and depth and diameter of corrosion pits. Then the relationship between the defect’s parameter and magnetic field amplitude was obtained. The experimental results showed that, whether corrosion or crack, the depth is a very important factor affecting the leakage magnetic field amplitude. Especially for crack, width, length and the inclination angle between crack and magnetic field had great influence on the detection of the cracks, and too small angle to lead to misjudgment and undetected of crack. Therefore, single direction inspection may lead to undetected in engineering practice.

An ultrasonic Rayleigh wave transducer was designed for nondestructive pressure measurement in vessels. Using polyimide resin as the wedge material, the Rayleigh wave transducer had two piezoelectric elements which were placed in the same wedge with a certain distance. Variations in pressure and temperature of vessels can affect the velocity of ultrasonic waves, which will affect variations in time delay in receiving of the same Rayleigh wave with the two piezoelectric elements of the designed transducer. Based on the acoustoelasticity principle and considered the effect of temperature, a practical correlation model between the time delay and both the pressure and temperature of vessels was developed. Using an air vessel as a specimen, Rayleigh wave transducers were arranged in the axial direction of the vessel. The results of temperature experiments show that effect of changes in temperature on time delay agree with the theoretical results. With the calculation temperature compensation in pressure experiment, the relationship between the variations in the time delay caused by changes of pressure and the pressure is established. The pressure measurement results show that the measurement model is effective and the maximum absolute error is 0.09 MPa, which could be acceptable in engineering application.

Ginkgo landslide, located in Ginkgo village, Xixia County in Henan province, is a large earthiness landslide. Considering its serious deformation and the possible serious instability disaster of the landslide, GPS was chosen to monitor this landside. This paper systematically introduces the monitoring program design, data acquisition, data processing, data analysis when GPS was used in Ginkgo landslide monitoring. According to GPS monitoring result analysis, the landslide is at a stage of constant speed deformation. And the rainfall is the main factor inducing the landslide sliding. It’s suggested that close attention should be paid to the landslide when encounter rainstorm, heavy rain or a long time raining so that to relief and prevent disasters.

The magnetic flux leakage (MFL) testing, as a modern nondestructive testing technology, requires fast and accurate signal progressing methods. A practical signal progressing method for MFL testing was presented, especially for tank floor MFL testing. According to the FFT result of the original signal, a difference amplifier and a low-pass filter were designed in the hardware signal progressing. In the digital signal progressing, a numerical differential progress and an IIR band-pass filter were adopted. Experimental results show that the presented method could effectively eliminate noise. Defect depth measuring results show that, for the 8 mm thickness specimen, the maximum absolute error of depth is 0.23 mm, which means 2.8 % of the 8 mm thickness.

Hydraulic shaker, equipment of simulating laboratory vibration environment, can accurately replicate the given power spectral density (PSD) and time history with an appropriate control algorithm. By studying method Hv estimator of frequency response function (FRF) estimation, a FRF identification strategy based on the Hv estimator is designed to increase the convergence rapidity and improve the system response function specialty. The system amplitude-frequency characteristics in some frequency points or frequency bands have large fluctuation. To solve this issue, a step-varying and frequency-sectioning iterative correction control algorithm is proposed for the control of 2-axial exciter PSD replication tests and the results show that the algorithm has a good effect on the control of hydraulic shaker, and can achieve reliable and high-precision PSD replication.

The continuous cooling transformation (CCT) behavior of a Ti attached steel was studied through thermal simulation tests, and the influences of different cooling rates on the microstructure and transformation were investigated. The results show that the microstructure changes with the cooling rate, and the CCT curve of studied steel is plotted, which indicates that the solid-state phase transformation mainly consists of four regions. The CCT diagram made it possible to predict the microstructures of studied steel with different cooling rates.

The CCT curve of a C-Si-Mn steel was investigated. The hot simulation tests at different cooling rates were conducted on Gleeble-1500 simulator and microstructures were observed. Based on transformation temperatures recorded by dilation curves and microstructures, the CCT curve diagram for tested steel was plotted. The effects of cooling rate on microstructure and transformation temperature were studied. The results provide the theoretical basis for determination of hot processing and heat treatment technology of C-Si-Mn steels.

This paper proposes a FPGA implementation to apply a stereo matching algorithm based on a kind of sparse census transform in a FPGA chip which can provide a high-definition dense disparity map in real-time. The parallel stereo matching algorithm core involves census transform, cost calculation and cost aggregation modules. The circuits of the algorithm core are modeled by the Matlab/Simulink-based tool box: DSP Builder. The system can process many different sizes of stereo pair images through a configuration interface. The maximum horizon resolution of stereo images is 2048.

Logistics distribution involves preparing goods in the distribution center or logistics node for most reasonable delivery according to the requirements of customers. Genetic algorithm is a random global search algorithm based on the principle of natural evolution. It can be a good solution to optimize the distribution routes. This paper combines genetic algorithm and the simulated annealing algorithm, to which memory device is added, in order to avoid best result losing in the crossover operator of the genetic algorithm. The experimental results show that a memory function with this genetic simulated annealing algorithm in solving the logistics distribution routing problem, can not only get a higher qualified solution, but can also significantly reduce the evolutionary generation that algorithm requires, and obtain solution to the problem in less time.

Heat generated during wire saw slicing can cause silicon temperature raise and make silicon wafer warpage, especially for larger silicon wafers. In order to study the wire saw effect on silicon temperature during slicing process, three kinds of wire saw, mainly semi-fixed abrasive wire saw and traditional wire saw, are applied for slicing silicon ingot. In this paper, the thermocouple is used to measure the temperature of the silicon during wire saw slicing. The experiment results show that the temperature of the silicon increases along with the wire saw working direction and reaches maximum value near the outlet position of silicon. The temperature of the silicon sliced by semi-fixed abrasive wire saw is lower than that sliced by traditional wire saw.

The precipitation in continuously casting slabs of a Ti-Nb microalloyed steel was studied. The samples were taken from different places along cross section of slabs and the precipitations were observed by TEM. The results show that the centre area of slab contains more precipitates of Ti-Nb and carbonitrides more uniformly distribute in the centre along thickness direction. Moreover, the precipitates in the middle are more than those in the edge along width direction of slab. Some large carbonitrides exist in the middle of slab because the temperature in the middle is higher during slab cooling resulting in the large precipitates. The study provides the basis for understanding the precipitation in slabs of Ti-Nb microalloyed steels.

The reactivity photoacoustic technology was used to detect the laser induced photoacoustic spectroscopy characteristics of explosives (PETN and HNS). The results showed that: the reflectivity of pure PETN and HNS under laser irradiation was large and the photoacoustic signal was weak. After doping with carbon nanotubes (CNTs) and carbon black (CB), the reflectivity decreased. The photothermal conversion and the optical absorption coefficient rate increased and the photoacoustic signal enhanced. For the same sample, the intensity of the signal was proportional to the incident laser energy. For the same explosives and under the same doping amount, the photoacoustic signal of the CNTs doped sample is greater than that of the CB doped sample. For the same sample and the same dopant, the greater the amount of doping, the stronger the photoacoustic signal. There was optimum ignition energy. By using TG-DSC technology for thermal analysis of the samples, the results from the thermal analysis could explain the reactivity photoacoustic experiment.

Acceleration iterative control is generally used in multi-degrees-of-freedom earthquake simulation test. To overcome the shortcoming of poor displacement amplitude accuracy in this control, a multi-degrees-of-freedom earthquake simulation control strategy based on multi-movement parameters iterative control is proposed. This control divide the frequency range of earthquake simulation test into displacement control area, the synthetic control area and acceleration control area from the low frequency to the high frequency, and correct the acceleration errors spectrum and displacement error spectrum by iterative control method, and produce shaker driver signal by synthesis method, and realize the displacement replication and acceleration replication at the same time. The experimental results which are got in multi-degrees-of-freedom earthquake simulation facility indicate that this control can achieve high accuracy multi-degrees-of-freedom earthquake simulation test after several times iterative.

Magnetic flux leakage (MFL) testing, as a modern nondestructive testing technology, has significant application in tank floor corrosion defect inspection. In view of signal characteristics in the MFL testing of tank floor, an improved signal progressing method combining software and hardware was presented. Especially, in order to avoid phase distortion caused by applying common digital filter, zero-phase digital filter which could effectively eliminate the phase distortion was proposed to improve the location accuracy of defect. Experiment results showed that the signal progressing method could improve signal-to-noise ratio, and the peak-peak value of defect signal had a good linear relationship with the depth of defect which showed that the proposed method could meet the requirement of the MFL testing. Comparing results showed that, the maximal location error of zero-phase filter was 2 mm and that of common digital filter was 24 mm, which showed that zero-phase filter had better defect location accuracy.

Water resources is the important strategic resources, and how to realize the sustainable is the world's theme, is the foundation of human survival. The purpose of this study is: useing building wastewater as the research object, using MBR (membrane bioreactor) technology as the sewage processing.Through the analysis on the actual case,put forward the reclaimed water process and operation cost accounting.It appears that the costs of water reuse is 0.83 yuan per ton, is in a very low level. The technology is in the actual water reuse processing, and have the reality significance.

Guangdong Sanshui Basin evoluted with extreme volcanic activities. Eruptions between Paleocene to Eocene were concentrated on Xinzhuang, Buxin, Baoyue and Huayong formations. For realized the relationship between various kind of rocks, Geochemistry analysis such as multi-element and rare-earth element determination were launched on Basalt, Trachyte and Rhyolite samples from the research area. Geochemistry diagram suggest that: REE distribution of Basalt followed as mid-plate alkali Basalt mode, while their trace element spider diagrams act as continental alkali Basalt with Nb, Ti rich and Sr loss. REE distribution of Trachyte and Rhyolite are similar, which indicate the same crystalization separation process. S-B diagram and Pearce diagram show that: Granite were partial melted from source region, while Trachyte in ZMY and Rhyolite in LBS originated from the same source region, and occur with the process of crystallization separation with plagioclase adventage.

Trachyte in Zoumaying was erupted in Eocene by 40Ar-39Ar age-dating in previous studies. Multielement Geochemistry analysis and U-Pd radiochronology were introduced on zircons from trachyte in Zoumaying in this paper. The SiO2 and K2O+Na2O contents of trachytes vary between 58.59% to 68.99%, and 10% to 11%. About twenty zircons were selected from trachyte sample with fractures and zonal structure, and most of them were inheritable magmatic zircons. The result of radiochronology on zircon is 60Ma which is similar with the former result as 53.2±0.2Ma.

The change mechanisms of fundamental frequency of runway under different conditions are discussed in this paper. A full scale cement concrete slab finite element model is built to analyze the relationship between foundation modulus and the fundamental frequency of runway. The results show that the coupling effect of runway plates can not be neglected. The minimum area affecting the fundamental frequency of runway is 45m in longitudinal and 15m in transversal according to the analysis of fundamental frequency of different size runway. The fundamental frequency of runway ranges from 7.5Hz to 23.6 Hz when the foundation modulus increases.

The cavitation regions of cylindrical and semi-cylindrical protrusions were experimentally investigated in non-circulating water tunnel. The cavitation numbers and structures of protrusions were compared under different velocities and aeration conditions, the common cavitation characteristics of protrusions were developed.

The forklift is the research object, for the reason of its large application quantities, high fuel consumption and bad emission. It is the important research direction of the energy saving of forklift to improve the working state of engine by means of hybrid technology. Based on the study of energy distribution, the schemes of parallel and series hybrid systems are evaluated, according to their fuel consumption, equipped power of working components and working parameters. The parallel hybrid system with the capacitor as energy accumulator and the project of energy regeneration with hydraulic motors are explored in detail, combining theoretical analysis. Finally, the energy regeneration,with hydraulic motor, is presented and synthetically evaluated.

An improved algorithm of the discrete orthogonal polynomial to identify the modal parameters is stated and a modal analysis system is designed and developed by object-oriented programming language Visual C++ here. Then proper experiment device is setup to collect signal data. Finally, compare the algorithm’s result with the ME’scopeVES’s and exam the algorithm’s correctness.

In pressure vessels design, WRC107 provides a typical method of local stress analysis to supports and attachments. But influence of the rigidity of attachments on calculation is not considered. For fatigue analysis of round hollow attachment on cylindrical shell, equivalent stresses calculated by WRC107 were compared with those by finite element method. Three attachment thickness configurations, that half, equal, double of the shell thickness were tested. Results show that, in key point Au defined by WRC107 equivalent stress decreases while attachment rigidity increases, and in key point Cu, equivalent stress increases while attachment rigidity increases. When the thickness of attachment equals to that of shell, equivalent stress of WRC107 in Cu comes closest to FEM.

The super-Gaussian random vibration test has increasingly attracted attention for its existed advantages in comparison with traditional random vibration test. The super-Gaussian random signal generation principle is investigated in study based on the research about control theory for the super-Gaussian random vibration test, meanwhile, super-Gaussian random drive signal used in control system is obtained from Poisson process and filter theory. The experiment proves that high control accuracy of output power spectrum and kurtosis can be realized by taking super-Gaussian random vibration control strategy proposed in paper, which is consistent with the requirement in engineering. In the end, super-Gaussian random vibration control system is applied into the Highly Accelerated life Testing(HALT) for the incandescent lamp, and a comparison between super-Gaussian random vibration test and traditional Gaussian distribution random vibration test is carried out, the comparison results indicate that super-Gaussian random vibration excitation signal comparing with Gaussian distribution signal can markedly quicken the fatigue failure process for incandescent lamp.

Multi-exciter vibration can provide greater thrust for overweight test specimen, achieve the uniformity of vibration for the special structure of the thin specimen, and overcome the shortcomings in single-exciter test, it becomes the trend of vibration test. Based on the control theory of multi-exciter vibration test, a system equilibrium synthesis is presented to make up for deficiencies of different methods for random vibration test control algorithm. the relevant experimental study is carried out on the experimental platform, experimental results show that dynamic control range of multi-exciter random vibration control system achieves 90dB in the self closed-loop control test. high precision is reached for self-spectrum control of actual test system after establishing multiple shaker, self-spectrum of control response is controlled in the range of ± 1.5dB, which satisfies requirements in engineering test.

he steel lined reinforced concrete penstocks (SLRCP) is always looked as an axisymmetric structure according to the design code, which can not show the true load-carrying capacity when considering the dam’s constraint to the SLRCP. In this paper, the physical non-axisymmetric property of the structure is simulated using the finite element method. The internal force distribution of every cross section in the SLRCP is studied, and a design method for steel arrangement based on axial force is proposed. When considering the non-axisymmetric property, the axial force in those cross sections approaching the bottom of the structure may be reduced more than 30% to the calculated value by the axisymmetric analysis. The larger the inner radius of the penstock or the thickness of the concrete wall is, the more marked the non-axisymmetric property of the SLRCP is.