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HT300 (Cast Iron) is widely used in heavy machines, and the metal magnetic memory (MMM) technique can is used to evaluate early damage of the following metal while calculating the stress concentration. An experimental investigation of the effect of stress on permeability of HT300 has been undertaken on cast iron. The result showed that the stress can alter the permeability of the material which will amplify the magnetic field of the specimen. Further, simulation was used to evaluate the characteristics of magnetic signal under different conditions. The present work indicate that the MMM can detect stress concentration and early stage of damage effectively.

Green manufacturing is a comprehensive consideration of environmental impact and resource efficiency of modern manufacturing mode. Remanufacturing is a typical application of green manufacturing. This paper establishes an evaluation indicator system for heavy machine tool remanufacturing scheme which contains 5 first-grade indicators and 13 second-grade indicators, and evaluation model for heavy machine tool remanufacturing scheme based on Analytic Network Process (ANP). Taking heavy machine tool remanufacturing scheme optimization for example, the weight and ranking results for heavy machine tool remanufacturing scheme can be obtained through the super matrix. Then it analyzes the impact of node sensitivity on the evaluation of machine tool remanufacturing scheme.

An acquisition system applying in transient electromagnetic method (TEM) receiver has been designed in this paper. The accuracy of acquisition has been improved by using a floating-point A/D with high input dynamic range, which is composed of programmable gain amplifiers (PGA) and a dual-channel 16 bit resolution ADC. The real-time performance can be ensured by using a field-programmable gate arrays (FPGA) as the main control unit to control ADC, PGA, data storage and communication interface. By integrating a soft core CPU, Nios II, in FPGA, the complexity of circuit design was decreased, and the work efficiency of system was improved. This system, which has good performance of real-time and high integration level, can meet the needs of TEM signal acquisition.

Finite element method(FEM) have been widely used in modern mechanical design,mesh generation is an important part of the finite element analysis,this article discussed the process of mesh generation through two practical cases and put forward some issues we should pay more attention to.

In this paper, we take secondary forest, orchard, and woodland soils of rubber in different planting years as a research subject and analyze the influence of different land use on soil organic matter. The results show that land use has significant influence on soil organic matter components (p orchard> rubber plantation. These differences are mainly due to the litter under different tillage quantity, quality and variety of management measures. While orchards and rubber plantation have used different tillage method, as a plantation by human, it was greatly influenced by human.

Speed is the core elements in table tennis athletics, however speed is lack of strength of the attack and lethality is limited, it is only with the aid of a force and speed of rotation to achieve the kill is the most optimized techniques. From the ping-pong rotating force, to elaborate the table tennis increased rotational mechanics principle and cause analysis, through the analysis of principles, deep space to carry out the table tennis rotating mechanical three-dimensional analysis, which provides a scientific theoretical basis and practical way for the table tennis rotation technique, its techniques can enhance new active exploration.

Biosorption of As3+ ions by industrial fermentation waste Aspergillus niger free dry mycelium was investigated in a batch system..The influences of solution pH, biosorbent dose, As3+concentration, and contact time on As3+ were studied.The results indicatd that absorption capacity was strongly affected by the solution pH, the biosobent dose and initial As3+concentration.Optimum biosorption was observed to be 75% at pH 5.0,biosorbent dose 20g/L, initial As3+concentration 800ug/L. Adsorption equilibrium was established in 100 min. Biosorption equilibrium data were best described by Langmuir isotherm model.

The cementation technology to deal with the mine tailings is adding cementation material and then dehydrating tailings and piling on suitable spot. In order to find the law of the mixing ratio of the cementitious material of the mine tailings of Xishimen Iron Mine, Portland cement and cementitious material A are selected to be compared in the experiment of strength test of cementation of the mine tailings of Xishimen Iron Mine. The result shows that both kinds of cementitious materials can meet the needs when the mixing ratio is 2-3%, but the cementation performance of material A is better than Portland cement. The experiment of adding admixture to improve the cementation performance of material A is carried and the result shows that Na2CO3 and KAl(SO4)2•12H2O can improve the strength of cemented whole tailings while Na2SO4 , CaSO4 and Na2SiO3is helpless to improve the strength.

A theoretical analysis model to calculate the spherical bearing rotational torque is established based on two assumptions: a) The spherical cap suffers uniformly distributed pressure along the convex surface, pointing towards the center of the sphere; b) The pressure on the rotating plate imposed by the spherical cap flat surface is distributed as a right trapezoid. Compared with the test results, it can be found that the value calculated according to the theoretical formula is closer to the experimental value than that calculated according to the code. Keywords: spherical bearing, rotational torque, bearing design, bearing test.

Creating comfortable interior microclimate environment with comparatively lower energy consumption is one of the basic aims in building design. Combined with the comprehensive retrofit design practice of Wuhan construction building, the thesis investigates a set of practical building climatic design method which is based on computer simulation and analysis technology. Meanwhile, this article analyses the climatic design strategies of Wuhan construction building, and provides a references for architects in the conceptual design stage in the future.

The temperature deformation of Jiashao Bridge is a serious problem. In order to solve this problem effectively, a kind of rigid hinge structure is adopted in the middle of the bridge. Unit sparse plate bridge expansion joint for multi-direction-displacement is installed on the rigid hinge of this bridge. Vibration reduction tests are needed to verify the performance of the expansion joint and the service condition of the bridge structure. In this paper, a finite element analysis of the rigid hinge expansion joint is performed and a vibration reduction test platform is designed.

In order to study the effect of different models on caisson-soil interaction, a linear model and two nonlinear models are established by finite element software SAP2000. It is found that with the increase of amplitude of seismic wave, the effect of nonlinear properties of caisson-soil interaction is increasingly large. The linear model, however, is not suitable any more under such condition, while the nonlinear models can simulate caisson-soil interaction reasonably.

In the complex ship noise environment, the effective signal should be extracted before the leakage signals of acquisition which often mix with noise signal do further analysis. So the signal processing method based on db5 wavelet transform is put forward. In order to make the signal-to-noise separation and restore the original signal waveform, wavelet de-noising processing is done for the pressure sensors receiving signal. Finally, the negative pressure wave method is used to find leakage location of ship pipeline. The experiment proved that the signal processing method based on db5 wavelet transform is suitable for complex ship noise environment and improves location accuracy.

The objective of this work is to find the law of combined effect of steel reinforcement and expansion agent (EA) on the crack resistance of ready-mixed concrete by doing flat-plate method experimental study on the crack resistance of ready-mixed concrete with EA, also with EA and steel reinforcement, with a deep analysis of the mechanism of reinforcement and EA on ready-mixed concrete. The paper comes to the role of ready-mixed concrete cracking performance which is influenced by reinforcement steel and EA.

Comprehensive railway passenger transport hub (CRPTH) is important node in both railway passenger transport net and urban traffic net The efficiency of its passenger collecting and distributing impacts the level of service of both. In this paper, we proposed the concept of urban traffic evacuation system for CRPTH, clarified the quantitative indicators of its evacuation efficiency, and discussed the process of the system optimization.

The objective of this work is to find the way of diameter and ratio of steel reinforcement impacting upon crack resistance of ready-mixed concrete. By analyzing the bonding theory of steel and ready-mixed concrete, as well as making an experimental study of plate cracking performance, it comes to the best reinforcement ratio. The conclusions are based on physical reasoning and available experimental dates, which can provide the user with references.

To eliminate the drifting in recordings from Ms8.0 Wenchuan earthquake, a modified two segments baseline correction method is brought up and systematic acceptance standard is presented. The method is applied to recordings from Qingping station and Bajiao station, which are closest stations to surface rupture traces. The effect of baseline correction on acceleration time history, Fourier amplitude spectrum and 5% damped relative displacement response spectrum is analyzed.

For asphalt pavement performance evaluation, pavement roughness, which is subject to cracks, potholes, road repairs and so on, is a major factor to influence riding quality. Therefore, riding quality is partly correlated with pavement distress, and the relationship can be transformed to that between pavement roughness and distress rate. However, this relationship is not clear, and not reflected in existing evaluation models. Thus, correlation analysis and non-parametric test of independent samples were applied in this paper to find that, international roughness index and pavement distress rate are significantly different due to different grades of roads, then, linear and nonlinear regression were used to analyze the relationships between international roughness index and pavement distress rate for different road grades. Furthermore, original data were processed by logarithmic transformation, radical transformation, exponential transformation and so on, based on which, corresponding relationships were analyzed by linear and nonlinear regression. Finally, best models to describe relationships between international roughness index and pavement distress rate for different road grades were solved out, and corresponding 90% confidence intervals were computed. Research in this paper offers a reference for improving asphalt pavement performance evaluation system and models, which is conducive to further theoretical research and practice.

Life prediction is one important of Engine research. Take-off EGTM is an important parameter to monitor Engine performance. Take-off EGTM have great influence on Engine life, Reducing EGT will help to extend Engine life on wing (LOW), thereby reducing operating costs. Aiming at Engine condition monitoring, the definition of take-off EGT Margin is given, estimation methods and their application on Engine life prediction are discussed.

This paper assumes that jump process in underlying assets-stock price is more common than Poisson process and derive the pricing formulas of some exotic options under the stochastic interest rates by martingale method with the risk-neutral hypothesis.

Life prediction is one important of area Engine research. Take-off EGTM is an important parameter to monitor Engine performance. Take-off EGTM have great influence on Engine life, Reducing EGT will help to extend Engine life on wing (LOW), thereby reducing operating costs. Aiming at aero-Engine condition monitoring, the definition of take-off EGT Margin is given, estimation methods and their application on Engine life prediction are discussed.

Leakage of ship pipeline system has become a great hidden danger, which affects safe operation of ship and causes environmental pollution. In order to isolate leaking pipeline safely in emergency conditions, Real-time monitoring of ship pipeline system leakage is very important. In this paper, the real-time models of ship isothermal and thermal pipeline were established with a set of equations which is running synchronized with the actual execution pipeline, and the real-time model method was used to monitor ship pipeline system leakage. If the difference between measured values and calculated values is greater than a certain range, pipeline leakage is identified. The location of leakage is calculated based on pressure gradient. Only pressure, flow and temperature of the first and second end of the pipeline were needed, can this method achieve leakage detecting and locating. According to the analysis and verification from the experimental data, this method has high leakage resolution and positioning accuracy.

This paper assumed that the stock price jump process for a special kind of renewal jump process, that is incident time interval for independent and subordinate to Gamma distribution random variable sequence. We obtain the European bi-direction option pricing formulas on jump diffusion model under the stochastic interest rates by simply mathematical induce by means of martingale method.