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Aiming at vehicle routing problem (VRP) with many extended features is widely used in actual life, multi-depot heterogeneous vehicle routing problem with soft time windows (MDHIVRPSTW) mathematical model is established. An improved ant colony optimization (IACO) is proposed for solving this model. Firstly, MDHIVRPSTW was transferred into different groups according to nearest depot method, then constructing the initial route by scanning algorithm (SA). Secondly, genetic operators were introduced, and then adjusting crossover probability and mutation probability adaptively in order to improve the global search ability of the algorithm. Moreover, smooth mechanism was used to improve the performance of ant colony optimization (ACO). Finally, 3-opt strategy was used to improve the local search ability. The proposed IACO has been tested on a 32-customer instance which was generated randomly. The experimental results show that IACO is superior to other three algorithms in terms of convergence speed and solution quality, thus the proposed method is effective and feasible, and the proposed model is better than conventional model.

Affected by the climate change and human activities, the consistency of Measured Runoff Series (MRS) is changing. The methods of reduction modification and current modification are commonly used to the inconsistent MRS in domestic, the modified runoff series will be used to water resources assessment as the basic data, but the methods that used to estimate the consistency of Reduction Runoff Series (RRS) and Current Runoff Series (CRS) is subjective to some extent. With the MRS/RRS/CRS from 1956 to 2000 of Huayuankou Station at Yellow River, the influence degree of human activities and climate change to the inconsistency of runoff series were analyzed preliminarily, then the hydrological alteration diagnosis system was used to estimate the consistency of runoff series, with the parameters of Hurst coefficient and the alteration classification, the modification effect of RRS/CRS was analyzed. The results show that, although the consistency of RRS/CRS was improved, the alteration still existed, they should be modified further more to satisfied the requirement of water resources assessment, or the assessment method that adjust to the inconsistent runoff series should be adopted.

To survive and prosper in a more competitive construction market nowadays, a company must strengthen the cost management of construction project. This paper expounds the present situation of the construction project cost management, existent problem in the process of the construction project cost management. Countermeasure analysis of perfecting the construction project cost management is discussed in respect to the management concept and method, information technology application, the people-oriented and sustainable concept of development.

Applying Wall tapping and roof sounding for coal blasting mining, excavation face to determine whether the status of roadway roof separation occurs. Firstly through beating the different parts of rock layers and record the received voice signal, which do the DTW feature extraction of the voice signal. Secondly based on the model database of constructed roof separated layer, determining the state of the roof combining with BP neural network recognition algorithm, after the extraction of DTW feature and the sequence data generated. Finally simulation and experiments show that identification method based on DTW, determining the state of the roof characteristic. Whether the roof separation of roadway occurs, to avoid the misjudgment problems of lack of experience in practical works.

The thermal fatigue behaviors of traditional Al-Si-Mg casting alloy and optimized Al-Si-Mg casting alloys at different thermal fatigue temperatures were investigated. Fatigue cracking appeared on the surface of traditional Al-Si-Mg alloy after 450 thermal cycles at 300 °C thermal fatigue temperature. However, the fatigue cracking was not found on the surface of optimized Al-Si-Mg alloy at the limited thermal fatigue cycles (less than 4450 times). Moreover, the optimized Al-Si-Mg alloy only occurred to elastic deformation and could not emerge in irreversible deformation. The grain refinement in the optimized Al-Si-Mg alloy could make the thermal fatigue cracking appeared much later and propagated much slowly. These results showed that the thermal fatigue resistance of optimized Al-Si-Mg alloy was superior to that of traditional Al-Si-Mg alloy.

This paper used the 3d modeling software to establish SOLID model and simplified it. And it used ANSYS workbench to make the simulation analysis on dynamic performance of the universal joint. Compared undamped free vibration modal analysis with the inherent frequency measurement experimental results, to verify the accuracy of the finite element model, and prove its no resonance phenomenon.

There are a lot of the potential security hazard in many rural breeding sheds. Some which are improper construction has jeopardized to people's lives and wealth. Peasants themselves mostly construct breeding sheds by the traditional empirical formula or the mimetic one in order to cost savings. Reasonable construction structure and correct building methods have a positive effect on reducing property loss and protecting people's safety.

This paper takes ball cage patterned constant speed universal joint of as the research object. Using the 3 d modeling software solidworks to establish solid model and simplified it . Based on ANSYS, do finite element contact stress analysis by the universal joint of the two kinds of condition. find out the weak part,through the improvement of raceway design parameters, Relieve the stress concentration phenomenon, reduces the maximum stress, increases the service life of universal joint.

In BOM product matching, there will be several product solutions based on the matching mechanism owing to the fuzziness and diversity of the customers needs. To select the optimal BOM through the matching process, a quantization method, which evaluates the product solutions according to customers intuitive estimate, is proposed. Customers needs are consisted by many parameters, and each parameter has several values. First, initialize the satisfaction level of every parameter value in the requirements through customers intuitive assessment. Second, as to a parameter, get the difference of satisfaction level of each parameter value by pairwise comparison. Third, revise the satisfaction level by the difference got by the second step. Other parameters are processed by the same method. Then, the satisfaction level of product BOM is calculated by the weighted average of the satisfaction levels of its constituent parameters. In this way, the BOM that best meets the customers requirements can be found out. The feasibility of the method is finally verified through an empirical study. This method can also be used in some other situations that contain fuzzy concept quantization.

Dynamic fracture of ductile metals at different strain rates and temperatures is studied via molecular dynamic simulations. The results show that both increase of temperature and decrease of strain rate reduce the yield strength, but the stress-strain curves separate prior to yield point at different temperatures. Both increase of temperature and strain rate shorten the duration of the stage of dislocation nucleation and slip. The stress-strain curves for various materials indicate that void nucleation needs not only lower yield strength but also lower fault energy. After the yield point, initially some defect clusters form along the loading direction. With the increasing of strain, small dislocation loops nucleate from some larger defect clusters, then quickly multiply and move on slip plane. When the stress exceeds a critical value, some voids nucleate in dislocation aggregation regions. The incipient void shapes are clavate and void distributions predominantly are along the perpendicular directions of tensile loading. Nucleated voids gradually grow into spherical-like shapes via emitting dislocations.

In order to determine coal seam gas content accurately, the single factor method was adopted to study geological factors that affect coal seam gas content of a coal mine. Bedrock depth, 50m influence coefficient and coal thickness are identified as the main controlling factors of gas content. And the corresponding correlation coefficient are: 0.6011, 0.3899, 0.2527. Factors such as effective trapping thickness, moisture content and ash content are regarded as secondary factors. Then the SVM theory was used to set up a nonlinear prediction model between coal seam gas content and main controlling factors, and the gas content was predicted. Results show that single factor method can be used to determine main controlling factors of coal seam gas and the gas content SVM model can predict gas content accurately. Besides, the research findings can provide technical basis for gas drainage and gas outburst prevention.

The large-displacement motion simulator which composed by Cartesian coordinate movement Desk and Three-axis turntable was designed in this paper. This Motion simulator can move the working spaces to any position of the space by any posture, which solved the disadvantages of the STEWART platform, the smaller spatial displacement and limited space corner. Kinematic analysis of the large-displacement motion simulator was discussed in this article, and theoretical modeling of the large-displacement motion simulator was presented by KANE equations. This has the theoretical significance for the research of the technology of space motion simulation and docking.

In this work, we reveals the statistical distribution law of 1-3mm coal particle size by MATLAB and the definition and probability distribution function of log-Weibull distribution. In order to get the theoretical probability model of the particle size distribution, we studied the parameter estimation of Weibull, lognormal and log-Weibull distribution though using the maximum likelihood estimation method. The comparison criterion Cc was introduced to evaluate the difference between the theoretical probability density model and the actual experimental data distribution. The results of comparison criterion shows when the particle size has a smaller intervals, log-Weibull distribution is better to predict the experimental data than Weibull distribution and has a smaller change with the different intervals of particle size than others.

In general, the sulfate isotope was used of the researching for the horizontal inflow groundwater, and discussed the source of the source of groundwater. This paper discusses the different depth and different area groundwater, the results indicate that, at the same groundwater flowing system, the different area and different depth, the sulfate isotope characteristics of groundwater have lots of differences, these differences indicate that the two area groundwater have the different source and the different process of minerals dissolve, and the hydraulic power between the two area groundwater is very weak.

The dynamic problem of a free-free beam with lumped masses distributed along the beam is researched. Effects of magnitude and position of lumped masses on bending mode and natural frequency of a free-free beam is studied. Method of lumped masses proposed in this paper is used to determine dynamic bending curves and natural frequencies. Least square method is used to give function fitting of the bending curves. The dynamic equations of a free-free beam are established by Lagrange method. Numerical simulation for dynamic response of the beam is carried out by MATLAB. The simulation results show that an impulsive load applied on the center of mass of the beam will result in small bending stress. However, a given larger impulsive load acting on one end or two ends of the beam will cause larger bending stress and plastic deformation at a cross-section and result in final failure.

The gas flow field in the swirl tube was studied by experimental measurement and numerical simulation. The results show that the simulation results based on the Reynolds stress turbulent model is in good agreement with the measured results probed by the five orifice Pitot-tube. Meantime, it is analyzed that there is short cut stream at the end of the exit tube, and at the dust discharge jaws, the particles are prone to be re-entrained from the hopper. All results above provide a base for further research on the optimization of the structure and the improvement of the separation performance of the swirl tube.

Taurine (Tau) was widely used in adjusting body normal physiological function and enhancing the ability of resisting all kinds of stress in clinical medicine and sports nutrition. This article collected the literatures of recent 20 years about the application of taurine in animal and human being. According to the chemical structure, amino acids in taurine’s molecular structure played a main role in regulating physiological function. Amino was the key and even the only functional group in biochemical reaction. Schiff’s Reaction between amino and carbonyl in reactive carbonyl compounds was that taurine played a variety biological function of molecular basis in cells.

This paper proposes a new isolation module, which is composed of double-layer tubular structures and the middle filling material. The hoop vibration isolation module is set somewhere out of pier footings of the footbridge, which presents some advantages such as good reliability, convenient construction, limited occupation areas, little damage to the environment and low cost. The energy of the vibration wave is confined at the most degree outside of the bridge pier, which reduces the vibration of beams and piers of footbridge. The present work gives an account of the experimental investigation on mitigation effects of the new vibration isolation module. The horizontal and vertical accelerations at test points under various working conditions were presented in this paper. Vibration levels were calculated to analyze the regularity of vibration attenuation, compared with no measures of vibration isolation. The results can provide some basic data for the mitigation of environment vibration arising from traffic loads.

The hydrological cycling of groundwater in Ordos Cretaceous Basin show obvious stratification, the cycle can be divided into three layers by cycling depth, the shallow, the intermediate and the deep. In this paper, a classification standard formed with geochemical and isotopic information is described. The standard is based on a large number of borehole investigation and stratified sampling. In the shallow layer, the groundwater mostly is fresh water with lower amount of total dissolved solids, the dominated anion is HCO3,tritium and 14C features show a high or rich properties; in the intermediate layer, the geochemical type of groundwater are SO4 or SO4-Cl, the age of groundwater calculated by 14C is less than 5000a; in the deep groundwater cycling, dominated anion show a complete evolution processes along the flow direction (HCO3-SO4-Cl) from recharge to discharge area, the groundwater age is commonly bigger than 5000a and even bigger than 10000a in the discharge area.

An experiment extracting CBM with surface borehole from mining subsidence area of a 6.25 meters thick coal-bed workface was done in Jincheng city. The test borehole was designed three stages based on the geologic structure of test field. During underground workface passed through borehole, the operational status of well was recorded and the deformation of casing was detected four times. Test has shown that the highest pure flow of surface borehole can reach 8m3/min which proves that the methane extraction technology with surface borehole from mining infection zone has a bright future for application in Jincheng city. But, how to maintain the stability of casing avoiding damage is still a problem, which should be resolved before the drawing technology is used in Jincheng extensively. Besides, the ordinary protecting skills for borehole used in oil exploitation cannot take a satisfactory effect to protect tube against damaging due to overburden rock movement during mining. The casing will be damaged at several positions, especially near the junction of soft and hard strata. It may be right measure to expend the diameter of tube or install special defensive joints at the places where will deform badly under the mining influence.

This paper deals with the mathematics model of two populations Commensalisms symbiosis and the stability of all equilibrium points the system. It has given the conclusion that there is only one stable equilibrium point the system. This paper also elucidates the biology meaning of the model and its equilibrium points.

The 22wt%WAl12intermetallic particulate reinforced Al-based matrix composite was successfully fabricated by press-forming technology using high-energy ball-milled powders. X-ray diffraction analysis shows that WAl12reinforcement phase has been obtained after in situ reaction of Al matrix with W14Al86alloy at 620°C. The mechanical properties of the composite material were studied at room temperature. The Young’s modulus, microhardness and the maximum ultimate tensile strength of this composite material can reach 75GPa, 1.51GPa and 471MPa, respectively. The results show that there is a good interfacial bonding between the Al matrix and WAl12particles. However, the composite cannot be applied in high temperature environment because of its fairly low strength residual ratio.

SiO2/Ag core-shell composite microspheres were synthesized by silver-seeding method in this paper. In the process, silver nanoparticles as seeds were deposited by repeating the cycle times for further formation of Ag shell. The effects of reaction power and time on the seeding of silica surfaces and the effect of silver ion on the growth of silver shells were investigated. Structures and properties were measured with TEM, UV, FT-IR and Infrared emissometer. The results showed the Ag nanoparticles on the silica surfaces were uniform in size. And the number density was increased growing with the increase of deposition. It was found that the composite exhibited a lower infrared emissivity value in the wavelength range from 8 to 14 μm than that of pure silica as a result of strong reflection of silver metal.

This paper is aimed to analyse contact stress of ring-plate indexing cam mechanism which is a new type of indexing cam mechanism. A contact finite element model of the cam and the pin gear is established with the commercial software of MATLAB and ANSYS. With the finite element analysis, the contact stress of the cam and the pin gear is predicted in one motion cycle. On the basis of the finite element analysis, the force and the position of maximum stress are obtained. The conclusion proposed here is reliable to instruct the design of ring-plate indexing cam mechanism.

The reliability of the nuclear power plant DCS is analyzed using Markov process to establish a mathematical model. And the initial use of the model on the three indicators of reliability parameters of nuclear power plants is calculated. The results showed that the model is correct,reliable and error rate is 9×10-10.DCS applies to preliminary analysis of the reliability of nuclear power DCS. Nuclear power plant DCS reliability is high enough, the minimum time of continuous operation is up to 66667 h, compared to conventional control methods more safe and reliable.

A mathematical model for predicting turbulence flows with effects of streamline curvature under orthogonal curvilinear coordinates is developed in this paper .The SIMPLEC solution procedure has been used for the transformed governing equations in the transformed domain. The flows near a groin in a straight open channel are employed to test the capability of the proposed turbulence model in capturing the effects of local curvature .The comparison between the computed results and experimental data shows a satisfactory agreement.

This paper is concerned with a mathematical model for numerical simulation of 2D flood waves due to partial dam-break. The governing water equations are solved by an implicit bidiagonal numerical scheme, based on the MacCormack’s predictor-corrector technique. The mathematical model is used to compute 2D flood waves due to partial instantaneous symmetrical dam-break in a rectangular open channel with a rectangular cylinder barrier downstream. Results, in terms of water velocity vectors and contours of water depth, water surface, following dam-break phenomena, are investigated in the two-dimensional problems.

Venturi device has important effect on pressure loss and flow field of flue-gas circulating fluidized bed desulphurization tower. Desulfurization tower is huge. Experimental study is difficult and costly. For these problems, PC-SIMPLE algorithm of Euler model of Fluent software is applied and flow condition of four different kinds Venturi tube are simulated in this paper. The pressure loss of curved Venturi is minimum. Three groups of Venturi tube can get uniform velocity field in the tower. Turbulence intensity of a group Venturi tube is maximum, followed by curved Venturi tube. But the turbulence intensity gradient of a group Venturi tube inside the absorber is also the largest. In order to get low pressure loss and better flow field, three groups Venturi tube is optimum.

The changes of tunnel rock stress caused by dynamic load is a hot point in geotechnical engineering. The paper introduces seismic methods of seismic design codes in China. The paper select state road 318(Huangcaoping part)as an example. Using finite difference software to analyze the rock pressure changes around the lining-tunnel with different seismic inputs. Comparing the results the rock static pressure and find the relative amplification factor between dynamic pressure and static pressure. Based on the results of analysis, we can obtain the following conclusions: As the peak ground motion acceleration increases, the peak value of tunnel rock increases, too. The amplifications change in a small range. The oblique parts of tunnel are the weakest parts of the tunnels. In different areas, the amplifications change a lot. The maximum ones are in the area of oblique.

A Detailed Transmission Electron Microscopy (TEM) Study Has Been Made of the Ageing Hardening Behavior of the γ1-Ti4Nb3Al9Precipitation Phase in the γ-TiAl Matrix in Ti-Al-Nb System. it Is Revealed that the γ1-Ti4Nb3Al9Precipitate, which Is Formed by a Normal Quench at 1473k and Ageing Treatment at 1073K, Takes Needle-Like Morphology with a Growing Axis Parallel to [001] Direction of the Matrix. the Needle-Like Precipitates Act as Barrier Grid to Inhibit Dislocation Moving on the Slipping Plane {111} of the γ-TiAl Matrix, which Helps to Improve the Strength of the Alloy. the Effects of the Third Element Niobium to the Strengthen of High Nb Containing TiAl Alloys Lie in Not only Solid Solution, but Also Ageing Hardening. the Interfaces between Precipitate and Matrix Are Also Investigated.

The mechanical properties and microstructure of high boron alloy (HBA) with different content of boron and carbon were investigated using Taguchi method for obtaining the optimized composition. In addition, the effect of modification with different RE content and the effect of heat treatment on the alloy were studied as well. Results show that the optimized chemical compositions of the HBA are as follows: 0.5% C、3.0% B、1.0% Si、1.0% Mn、1.0% Cu、1.5% Cr、0.5% V and the rest is Fe, and the best content of the RE are 0.8%-1.0%. After the modification and the heat treatment, the mechanical properties of alloy improve significantly. This is because that the matrix of alloy is changed from pearlite to martensite, and the network of boride is broken up and distributed more evenly to form an isolated and discontinuous distribution. The alloy with this composition has been successfully used for anode claw in aluminum smelter, which greatly improves the wear resistance.

Evaluating the health level of vehicles usually involves several factors and often needs to introduce subjective information. This paper presents an approach to combine several performance measures into a composite index for health evaluation. A mathematical method is proposed to estimate the overall performances of vehicles based on the observed performances under multiple measures or criteria. The approach is illustrated using a real-world example.