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© 2013 IEEE. The most commonly used single feature-based anomaly detection method for the complex machinery, such as large wind power equipment, steam turbine generator sets, and reciprocating compressors, exhibits a defect of low-alarm accuracy due to the non-stationary characteristic of the vibration signals. In order to improve the accuracy of fault detection, a novel method based on the Dirichlet process mixture model (DPMM) is proposed. First, the features of the mechanical vibration signals are used to construct the feature space of the equipment. The DPMM modeling method is then applied to self-learn the probabilistic mixture model of the feature space. The normal working condition model is used as the benchmark model. The early fault detection is realized by using a precise difference measurement method based on Kullback-Leibler divergence to calculate the difference between the real-time model and the benchmark model accurately, and by comparing the calculation result with a self-learned alarm threshold. The effectiveness and the adaptability of this novel early fault detection method are verified by comparing it to the single feature-based anomaly detection method and the Gaussian mixture model (GMM)-based early fault detection method.

Installing viscoelastic dampers on electrical transmission tower will significantly reduce the wind-induced vibration response of electrical transmission tower-line system. On the basis of the concept of strain energy method with the combination of related codes and the theories of calculation for equivalent damping,a mothed is presented which is used to estimate the additional damping of electrical transmission tower-line system with viscoelastic dampers.Through a electrical transmission tower with viscoelastic dampers, based on the formula of strain energy in design code,this paper puts forward a calculation method of equivalent damping ratio based on the concept story of transmission tower,and through finite element model the responses of transmission tower with viscoelastic dampers model and the one with additional damping ratio model were compared.The simulation results show that the calculation method of equivalent damping ratio has high precision,and the errors are less than 5% in multi engineering conditions.

The behavior of flow stress of Al-Mn alloy during hot compression at the condition of ε=0.05,0.5,5,25s-1 while the temperature range from 300°C to 450°C was studied by Gleblee-3500. The results show that the Al-Mn alloy possess the remarkable characteristic of a peak stress, followed by a steady-state flow stress when deformed in the temperature range from 300°C to 450°C with a strain rates range from 0.05s-1 to 0.5s-1.When the strain rate is higher than 5s-1 dynamic recrystallization will happen. The true stress decrease with increasing compression temperature and increases with the increasing strain rate. A constitution equation which can describe the relationship of ε,T and σ is achieved. Also the activation energy for deformation is calculated.

A laser amplifier of LD pumping Nd: glass with a high beam quality and stability, which amplifies nanosecond laser pulse, has been developed in this paper. The device adopts the major technology of “LD pumping multi pass amplification together”. Beam transmission is designed with the technology of “inhibition of diffraction effect, active control and spatial filtering”.

According to the characteristics of functional fibers and the performance requirements of underwear product, we selected chitin ,cotton and wool fiber as raw material, and developed two different structural underwear fabrics, Based on the experimental test, the wearability hydroscopicity, vapor permeability and anti-bacterial property were analysed and studied. The results showed that the designed fabrics have excellent hydroscopicity, vapor permeability and anti-bacterial function. as well as excellent wearability. Therefore, the underwears made of these fabrics willl not only be comfortable to wear , but also have excellent health care function. Therefore, they are ideal fabrics for making high–quality underwears

Based on analyses on mineral composition, mechanical property and hydrology property, large-scale triaxial shear test and vibration test were used to study the effect on strength and deformation characteristic, which was caused by wet-chemical and soften of the fillings. Then trial roadbed was filled with 3 typical rocks. Modulus of resilience on the top of the roadbed was gotten via a larger-diameter (D=75 cm) plate loading test which could provide important parameter for pavement structure design. Wet-chemical deformation is researched under constant load amount to deadweight of the roadbed. Experiment results show : (1)single-axle compressive strength (>15 MPa) and modulus of resilience (E0=91.7 MPa) of 3 fillings match the requirement according to specification; (2) these 3 rocks can be used as filling in roadbed; (3) as the fillings have wet-chemical, soften, and expansion properties, the suggestion of damp-proofing and drainage works should be adopted in construction.

In order to obtain the directional microstructure of different supersaturation and growing velocity, three simulations is calculated with different initial temperature. When the initial temperature is 1576K, and the supersaturation and growing velocity are smaller. The average space length of columnar crystals is bigger, and microsegregation is smaller. when the initial temperature is 1574K, the supersaturation and growing velocity increase. The average space length of columnar crystals decreases, and microsegregation increase; when the initial temperature falls to 1566K, the supersaturation and growing velocity reach 1.176 and 3.238 cm per second. The microsegregation decreases rapidly. The average space length of columnar crystals is the smallest. The solute curve of columnar crystal is like a “U” figure. When the growing velocity is bigger than VA, the phenomenon of solute trapping takes place.

Phase-field method can be used to describe the complicated morphologies of crystal growth without explicitly tracking the complex phase boundaries. The conformation of volume free energy is very important for microstructure simulation with phase-field method. However, the conformation of volume free energy is still correspondingly simple and ideal at present. In this paper, a new conformation method of free energy is mentioned. Free energy of each phase at appointed states is calculated by Thermo-Calc software. In order to avoided calculation, free energy of each phase is fitted by multiple-point function according to sub- regular solution model. It is obtained that the free energy data and phase graph data of α phase, θ phase and L phase in the extension, temperature (791-841) K and component (0-35)Cu(at.%) with Al-Cu eutectic alloy. The new phase model is also founded, and used to calculate microstructure evolution of Al-Cu eutectic alloy.

In this study W was found to have strong effects on solidification structure of the binary alloy. Based 0.5 W0、W0 and 1.5W0 base W0, three conditions with free energy base W equal to 0.5 W0, W0 and 1.5W0 respectively were computed. The results showed that the variation of energy base contributed a lot to the development of side branches of equiaxed dendrite structures, the lower W, the more developed side branches, the higher W, the more restrained side branches. Furthermore, the effects of boundary layer thickness δ on solidification structures were also studied. It is found that when the layer thickness δ is as small as Δx/0.94, computational errors occurred at the base of the dendrite and when the layer thickness δ is as big as Δx/0.54, some irreal phenomena, such as coarsened dendrite trunks and maladjusted side branches, could be caused. Further study on space step Δx showed that bigger space steps made higher computational errors. It is given that the relationships among phase-field perturbation, space step and solidification structure.

In this paper, microstructure of AL-Cu eutectic alloy is simulated by improving Nestler’s multiphase-field model. The exact physical parameters are used in multiphase-field model, and obtained the steady calculational results. In this numerical calculation, AL and AL2Cu are regard as two independent components. The eutectic microstructure is regard as an admixture of single phase α (AL) and single phase θ (AL2Cu). Using the model, steady eutectic layered growth is simulated, and the simulated results agree well with the solidification theory. At the same time, the stochastic noise is introduced, and eutectic free layered growth microstructure is simulated. The microstructure of primary dendritic crystal and pseudoeutectic is also simulated by enlarging the calculational interval scale, and obtained a better result.

Based on analyses on mineral composition, mechanical property and hydrology property, three kind of samples are made in both drying state and saturated state respectively. Large-scale triaxial shear test, compression test and vibration test are applied on these samples. Through comparative analysis of test data, wet-chemical property of the samples is studied. Studies show that three samples have wet-chemical property in saturated state, which appears as decreasing of strengthen and increasing of deformation. Mechanism of wet-chemical property is also studied in two ways. On the one hand, filling particles is lubricated by water and re-construction of structure takes place between particles. On the other hand, soften and wet-chemical properties of mineral component are the internal factor causing the deformation. At last, some suggestions are given on construction of roadbed filled with this highly weathered rock.

In order to discuss on highly weathered metamorphic fillers as soft stone fillers，firstly the CBR tests for analysis on viability as embankment filler are conducted on three different highly weathered metamorphic fillers. Secondly the rock strength tests and particle broken tests are processed to study on how weathered degree and rock structure have an effect on them. Based on the above conclusions, evaluation criteria are proposed that have certain guidance and reference on mountainous highway construction.