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The wear phenomenon of the braking surface of a high-power disc brake under emergency braking conditions is analyzed in this paper. Considering the classical Archard wear model, including the influence of the braking load, speed, and friction coefficient on the braking surface, the wear model of the brake disc surface is established to obtain the wear depth and distribution. It is essential to investigate the wear mechanism of the brake disc surface, and the evolution of wear laws is revealed under different braking parameters. The results have shown that the brake disc surface wear is constantly accumulating. The large load, the high speed, and the large friction coefficient would aggravate the surface wear area. It is expected that the wear study of the brake disc surface can guide the design of the disc brake.

During the process of Carbon Capture and Storage, some impurity may be found in the supercritical CO2fluid. The changes in corrosion of X70 Steel in water-saturated supercritical CO2system caused by impurity has been studied by the simulation experiment. The average corrosion rate was got from weight loss measurement. The morphologies and compositions of corrosion products were analyzed by SEM, EDS and XRD. It was observed that the existence of separate impurity would aggravate the corrosion of X70 steel in the water-saturated supercritical CO2system. The average corrosion rate was the highest when NO2or SO2was included, followed by H2S, and the average corrosion rate was the smallest when O2was contained. Among them, X70 steel suffered local corrosion when NO2was contained. The corrosion scale was monolayer structure of FeCO3under the supercritical CO2-H2O system. After the addition of O2, Fe2O3appeared in the corrosion scale, indicating that the oxygen corrosion process occurred. While with the addition of H2S, corrosion scales were double layers. FeS was mainly present in the outer layer. The corrosion process was controlled by CO2and H2S. The corrosion products were mostly FeSO3·xH2O and a spot of FeCO3when SO2was contained. SO2mainly governed the corrosion process. Besides, corrosion product was Fe2O3without FeCO3in the supercritical CO2-H2O-NO2system, NO2completely controlled the corrosion process.

Aggregate-mortar interface transition zone is a major factor for mechanical properties and durability of materials. Owing to the distinctive features of interface transition zone, this study reviewed research methods, structure models, improving methods and the influence to mechanics and durability of concrete of this zone. We also analyzed various test methods which are referred to in this review and their applicability, and discussed the formation mechanism and improving approach for interface transition zone. Our investigation suggested further scientific test is necessary for researching mechanical property of the interface.

As one of the key components of non-ballast slab track in high speed railway, cement asphalt emulsion mortar (CAM) has low compressive strength and low elastic modulus. This makes CAM possible to be served as supporting, height-adjusting, vibration-dissipating and deformation-fitting sandwich-layer between pre-stress slab and concrete roadbed. To study the fatigue behavior of the CAM, fatigue tests were conducted at room temperature and negative temperature, respectively. The permanent strain, elastic modulus and yield strength of fatigue-tested specimens were compared to the reference one. The results showed that the small permanent deformation lead to very little displacement differences among the slab track system. Secondly, the elastic modulus and yield strength of fatigue test specimens were both higher than that of reference one. Because the fatigue process might strengthen the CAM by compacting micro-cracks. Additionally, arising from the temperature sensitivity of asphalt, viscosity behavior of asphalt mortar at room temperature is changed to brittleness behavior at negative temperature.

Water-cement ratio is an important parameter of concrete quality. Rapid measurement of fresh concrete water-cement ratio can effectively monitor the on-site concrete quality management and play a great role in quality control. We study the variation of fresh concrete resistivity with the aid of electrodeless cement concrete resistivity meter, and discuss the impact of water-cement ratio under different varieties of cement, mineral admixture, chemical admixtures conditions on fresh concrete resistivity. We establish the relationships between fresh concrete resistivity and water-cement ratio based on the law of Portland cement initial hydration resistivity. The studies show that: fresh concrete resistivity is most vulnerable to the changes of water-cement ratio; there is a correlation between the law of fresh concrete resistivity and water-cement ratio; according to the fresh concrete resistivity variation, we can quickly identify water-cement ratio, cement and other parameters.

Cold rolling (CR) was conducted on coarse grained (CG) and ultrafine-grained (UFG) coppers, obtained by 1 and 8 passes in the equal channel angel pressing (ECAP), to investigate the effect of grain size on rolling texture. The microstructure was refined to UFG (~420 nm) with the ECAP pass increased to 8, while only band-like CG microstructure was observed in the 1 pass processed copper. The influence of the texture before CR could be excluded as the crystallographic texture kept similar for different ECAP pass. Pole figures (PFs) showed that the shear texture introduced by ECAP was replaced by rolling texture after CR. Furthermore, the rolling texture was a kind of classical copper-type for the CG copper, while a brass-type rolling texture was observed in the UFG copper. TEM results confirmed that the deformation nanotwins were only observed in the UFG copper, while the microstructure of CG copper was further compressed and subdivided. It indicated that the observed differences in rolling texture component and density might be contributed to the grain size effect which resulted in different deformation mechanism and grain subdivision behavior.

Based on the research of Linux kernel file system and embeded development environment, to build the Linux root file system from the bottom, to complete the development environment of Qt and Opencv dynamic library transplantation, through the efficient development platform and streamlined building the file system, realize the use of fewer resources to complete the application of machine vision in the ARM development board, make contributions to the future development of intelligent mobile terminal.

The ablation behaviors of 3D fine woven pierced carbon/carbon (C/C) composites were tested on an arc heater and their ablation morphologies were observed by scanning electron microscopy (SEM). It shows that ablation of 3D fine woven pierced C/C composites tends to start at interfaces, defects and pores. Cracks mainly yield at the boundaries of carbon fiber bundles, interfaces of carbon fiber felts during the ablating processes. The ablation properties of 3D C/C composites in parallel direction are better than that in vertical direction. In addition, the work indicates that the ablation process is mainly controlled by mechanical denudation.

Localization technology is enabling technology for wireless sensor applications. In order to improve the localization accuracy of wireless sensor network node, this paper proposes a mobile anchor node localization based on a layered approach. First area for wireless sensor networks slicing. Each layer consists of a number of equilateral triangles. Anchor nodes in each layer moves along the edge of the equilateral triangle to locate unknown node. After receiving the position information of the anchor node, unknown node to determine their own position by the triangular positioning.

Effect of pulsed magnetic field treatment on the microstructure and mechanical properties of Mg97Y2Zn1 alloy has been investigated. When the pulsed magnetic field is applied on the alloy in semi-solid state, the α-Mg was modified from developed dendrite to fine rosette, resulting in a refined solidification microstructure with the grain size decreased from 4 mm to 0.5 mm. The volume fraction of the second phase ( X phase) increased by about 10 %. The yield strength, fracture strength and plasticity were improved by 21 MPa, 38 MPa and 2.4 %, respectively. The improvement of mechanical properties was attributed to the refined grain size and increased volume fraction of X phase.

This system based on single-chip microcomputer control, with buttons and LCD monitor as the man-machine interface of numerical control dc power supply. System is mainly composed of rectification filter circuit, the output current control module, LCD display module current and voltage controlled constant current module. Button to SCM number controls the size of the output current DAC0832, LCD display the current value. This system controlled by single chip microcomputer DA output, make the whole circuit system has a stable output current, step precision is high, easy to control, etc.

With the rapid development of China's real estate industry, customers demand for real estate products has changed from the satisfaction of one single criteria to a much more diverse and individualized developmental orientation. But the value evaluation for real estate products varies from person to person, which leads to different customer value. In our country, as one branch market of the real estate industry, the green real estate market should get a thoroughly understanding about the composition of customer value, identify the target customer demand, provide more innovative value for customers, inspire and guide the customer purchasing behavior. This paper, through an analysis of the composition and affected factors of the customer value in green real estate enterprise, aims to conclude the methods for the optimization and innovation of the customer value in green real estate enterprise.

In this paper, a neural network sliding mode controller for a kind of 5DOFs robotic manipulator is proposed. A radial basis function (RBF) neural network is used as an estimator to approximate uncertainties of the system. The learning algorithm of the neural network improves the performance of the system. A globle terminal sliding mode control (GTSMC) is designed to guarantee the stability and improve the dynamic performance of the robotic manipulator. Simulation results show that the proposed NNSMC strategy is effective to ensure the robustness and dynamic performance of the 5DOFs robotic manipulator.

Missile control system is not block strict feedback system which is suitable to use backstepping method. So in this paper, a backstepping control method is proposed to design a missile longitudinal autopilot and is proved to be asymptotically stable by Lyapunov stability theory. The simulation results show that the designed system can still track commands quickly and accurately and is robust with aerodynamic perturbation and control input saturation.

In this paper, a design of an automatic measuring instrument of dam horizontal deformation based on laser scan concept is introduced. According to the demand of the dam deformation monitoring, the design chooses STM32F103CBT6 as the hardware control platform, and the laser scan concept is introduced. The measuring principle, main hardware design scheme and software flow chart are introduced in this paper.

This paper explains in detail design and implementation of PCIe driver in Linux operating system, First of all, it introduces briefly characteristics of PCIe bus; secondly, it gives a detailed analysis of how to write PCIe bus driver and how to write PCIe device driver of virtex5 series FPGA development board; finally, a test program is wrote in the application layer to verify correctness and stability of PCIe driver.

First designed the SVG has based on direct-coupled, rated capacity 200kVar, rated voltage of 10kV. Elaborate the system configuration of the main circuit, the selection method of the inverter, the diode rectifying devices DC side capacitor and other devices, and control method. Then carry out MATLAB simulation on the designed SVG to verify the correctness of the direct-coupled SVG hardware circuit; when the load changes, SVG can quickly convert operating mode, compensate reactive current.

As a result of the need, not only the Linux NIC driver but also the Linux PCIe driver needs to be used in vehicle automation. The nested driver technique have its greatest use in mechanical automation, in this thesis, analysis and research have been made for Linux nested driver which was based on FPGA detailedly, firstly, it provides a simple review of standard NIC driver in the Linux operating system; secondly, Linux PCIe driver which was based on FPGA is presented simply; finally, it gives a brief explanation of how to call some functions of PCIe driver in the Linux standard NIC driver, and the accuracy and stability of Linux nested driver were tested and verified by a program in the application layer.

The tuning exchange bias HE at martensitic state of Ni50Mn36Sn14 alloy has been investigated by means of hysteresis loop measurement. It was found that the whole loop can be tuned by HFC from a double-shifted to a single-shifted hysteresis loop, leading to an appearance of maximum HEat HFC = 0.5 kOe. This behavior could be ascribed to the competition between two types of AFM clusters and HFC,which exhibits predominantly atlow HFC range, while the competition between FM clusters and HFC, which becomes predominant at high HFC range.

Effect of Co or Cu slightly introduced in Ni50Mn35In15on martensitic transformation and magnetocaloric effect was investigated. The small doping of Co can modify exchange interaction between Mn atoms, resulting in the ferromagnetic ordering of the parent phase and a large magnetization difference across the martensitic transformation. For Cu-doped sample, a large was obtained, and gives rise to a large magnetic entropy change of 58.4 J/kg K for 5 T near room temperature accompanying with smaller hysteresis losses. The study on the doping system may have significant impact on realization of room-temperature magnetic refrigeration.

LiFePO4/C cathode materials were synthesized by Sol-gel method under the same process conditions using different water-soluble lithium source (LiOH, Li2CO3, LiNO3). The phase of synthesized powders were characterized by XRD; and the electrochemical performance of the material was investigated by measurements of cyclic voltammetry, AC impedance measurements, charge and discharge. The results show that the synthesized LiFePO4/C using LiOH as the lithium source has high electrochemical reversibility and low internal impedance. The specific discharge capacity is 147.5mAh/g under the discharge at 0.2C rate. It also has high stability of cycle capacity, and almost no attenuation after 30 cycles. So it has the excellent electrochemical performance.

A new Mg65Cu18Ni6Gd11 bulk metallic glass (BMG) with high level of Ni content, exhibiting glass-forming ability (GFA) of 6 mm, was fabricated by copper mold casting. The compressive strength and plasticity of the Mg65Cu18Ni6Gd11 BMG were 938 MPa and 0.14%, respectively. The composition design of the Mg65Cu18Ni6Gd11 BMG with enhanced GFA had succeeded simply using Gd substituting Y in the Mg65Cu18Ni6Y11 BMG, which was a result of a comparison on the GFA between the Mg-TM-Gd and Mg-TM-Y BMGs (TM: transition metals). Compared to the Mg-TM-Y BMGs, the Mg-TM-Gd BMGs exhibited improved GFA, which was demonstrated to be mainly attributed to the more negative amorphous formation enthalpy resulting from Gd substituting Y. The effects of rare earth (RE) elements on the GFA of Mg-TM-RE were discussed. This work may suggest an easy way for developing new Mg-based BMGs with improved GFA by rare earth (RE) design.

Asphalt mixture compaction is an important procedure of asphalt mixture construction and can significantly affect the performance of asphalt pavement. In this paper, an open source DEM code was applied to simulate the compaction of hot-mix asphalt (HMA) with the Superpave gyratory compactor. The asphalt mixture compaction process, air voids distribution, internal coarse aggregate structure, and the effect of CA ratio were investigated from a microscopic point of view. The analysis results show that DEM simulation is an economical and effective approach to the research of asphalt mixture compaction, and has tremendous potential for asphalt mixture design.

This paper studied different size-distribution of recycled coarse aggregates by fractal theory. Cement Stabilized Recycled Aggregate Mixture were prepared by different fractal rate aggregate gradations and the unconfined compressive strength at 7 d and 28 d of the materials were tested. The results showed that the unconfined compressive strength at 7 d and 28 d of the materials with recycled coarse aggregate were higher than the one with natural aggregate when coarse aggregate gradations were same. The higher source rock strength of recycled coarse aggregate was, the larger base material strength was. Generally, the increase of fractal dimension is conducive to the growth of strength. The base materials performances of the same fractal dimension were different when the max particle size was different. So the fractal dimension of recycled coarse aggregate must be determined by maximum particle size.

Laboratory experiments were conducted in this study to investigate the suitability and applicability of incorporating fly ash, bottom ash and paper sludge with various contents into CLSM mixtures. Fly ash was used as a substitute for Portland cement, bottom ash was added by partially replacing fine aggregate, while paper sludge was treated as a fibrous admixture. Physical and mechanically properties of the CLSM mixtures were examined through flowability, compressive strength, and splitting tensile strength tests. The test results indicated that both fly ash and bottom ash can be potentially used as basic materials for CLSM mixtures with desirable performances, and by limiting the amount of cement used in the mixture, the ultimate strength of CLSM could be easily controlled available for excavation. The strength of the CLSM mixtures were reduced to some extent by incorporating high content of fly ash, while they were significantly increased with high content of natural sand replaced by bottom ash. Due to the high water absorption of the paper sludge, the mixture with paper sludge added exhibited relatively low flowability, and it showed no benefits on enhancing compressive and splitting tensile strengths as common fibrous materials.

The effect of fly ash (FA) and slag (SG) on the anti-cracking performance of recycled aggregate concrete (RAC) is discussed, taking the toughness index as the concrete anti-cracking performance evaluation index, and the mechanism of action is researched at the meantime. The experimental results show that the strength of RAC is reduced when containing fly ash only or slag only, but the crack-resistance of RAC is improved significantly at 3 days and 28 days of hydration process of RAC. Furthermore, the 28 days anti-cracking performance of RCA improved significantly with 30% FA single-doped or 20% SG single-doped .It can improve the 28 days anti-cracking performance of RAC, by using double-mixture of fly ash and slag, there is an optimal FA/SG ratio and a best total content, the FA/SG ratio is 3:1 and the total content is 30%.

this paper analyzes and studies nature of BPF filter based on Libpcap, first of all, it analyzes location and structure of BPF filter in the Linux system kernel; secondly, it gives a detailed analysis of how BPF deals with filter described by a high-level language; finally, a filter described by a high-level language is presented, and a application program uses this filter to capture required network data packet.

Combining Shi Wu Passenger Dedicated Line and considering the effect of variety and content of mineral admixtures on concrete performance, the paper has investigated the microscopic structural’s variation of C40 high performance used in non-ballasted track base plate under the coupling conditions of acid rain and carbonization by using micro-testing methods such as SEM and XRD and optimizing mix design.The effect of variation on concrete performance has also been analyzed. Results show that when the concrete was eroded in coupling conditions of acid rain and carbon corrosion, C40 high performance concrete specimens produced a certain amount of acicular and columnar ettringite, the surface structure was loose, and pore increased, in addition, plate Ca(OH)2 crystal content gradually decreased with increasing of age, the concrete strength decreased, the maximum reducing value reached to 27%, what's more, the depth of neutralization increased with age. For different erosion pattern, its influence law was: S mode＜ST mode＜TS mode＜T mode.

An orthogonal experimental design method was adopted for the mix design of high early strength recycled aggregate concrete (HSRAC), and the influence of water-binder ratio, percentage of recycled aggregate(RA）and highly active compound mineral admixture (HACMA) content on the strength of the concrete was discussed. The test results indicated that water-binder ratio was the most principal and significant influencing factor on the strength of HSRAC, regardless of age. An empirical relationship among the strength of HSRAC, the water-binder ratio, the percentage of recycled aggregate and HACMA content was proposed by using multivariate regression analysis. The demand of opening heavy or heavier traffics and rapid repair concrete on strength to HSRAC could be all met.

Because of some drawbacks including low strength, poor dimensional stability, low abrasion resistance, easy to crack and other shortcomings, Portland cement concrete was limited to use as a dominant pavement material in highway construction. This paper studied the feasibility of making high performance pavement concrete by adding 20-40% of high-quality composite ultra-fine fly ash (CUFA) technology to achieve high-performance of concrete roads have been studied. The test results indicated that: with cementitious material content of 360~400 kg/m3 and CUFA content of 20% ~ 40%, adding CUFA improved the workability of concrete significantly; in the meantime, the 28d compressive strength was as high as 50 MPa, and the later strength of concrete continued growing. The designed concrete satisfied the requirements of opening to traffic after 3 days after the construction and heavy and extra heavy traffic in 28 days. The durability, especially the abrasion resistance, and the crack-resistance were improved significantly. The designed pavement concrete not only had a good compressive performance for practical engineering but also had good technical, economic, social and environmental benefits.

The wasted cement mortar and internal cracks induced by the secondary breaking process existing on/in recycled aggregates lead to significant reductions in the apparent density, strength and durability of recycled aggregate concrete compared to those of natural aggregate concrete. In this study, recycled aggregate intensification approaches was proposed by removing the old cement mortar from recycled aggregate surface through mechanical agitation, and immersing the recycled aggregate in chemical solutions. A series of laboratory experiments were carried out to validate that the proposed approach could improve various performances of the recycled aggregate, as well as the concrete made of it. The testing results showed that through the combination treatment or modification of mechanical and chemical intensification, both of the compressive and flexural strength of the recycled aggregate concrete could be increased to some extent.

Based on engineering practice, autogenous volume deformation and creep properties of C60 high performance concrete(C60 HPC) and C60 high strength concrete(C60 HSC) were evaluated in the study. The results showed that the cement partly-replaced with fly ash could significantly decrease the creep deformation, creep coefficient and creep degree. In comparison with C60 HSC, the creep coefficient and creep degree of C60 HPC were decreased 17.9％and15.8％ in 28 days, 22.9% and 21.0% in 270 days. For C60 HPC and C60 HSC at the same age, autogenous volume deformation of C60 HPC is greater than that of C60 HSC, but they were both less than 80×10-6 , and the autogenous volume deformation was basically completed in 7 days.

It is studied the effect of binder quantity, water binder ratio on properties of self-compacting concrete made with recycled coarse aggregates. It can be prepared C50 self-compacting concrete made with recycled coarse aggregate by adjusting send proportion, binder quantity, and mixing mineral additive. For example, when the binder quantity is 600 kg/m3, water binder ratio is 0.28, the flexural strength and compressive strength at 28 days of self-compacting concrete made with recycled coarse aggregates are 9.07 MPa and 68.47 MPa respectively.

The effects of mineral admixtures and superplasticizer on reducing the hydration heat of cementitious material were evaluated in this study, and the heat evolution rate and hydration heat were tested as the two parameters to evaluate the effect of improvement. The results showed that the cement partly-replaced with fly ash (FA) and slag (SG) could significantly decrease the release rate of hydration heat on the early stage of hydration, and lower the peak value of the heat evolution rate. The superplasticizer (TJ-Ⅲ) could reduce the hydration heat mainly on the early stage of hydration, and extended the induction period. In comparison with slag, the fly ash had more active effects on reducing the peak value and release rate of hydration heat.

It was tested the strength and wear value of recycled aggregate concrete mixing fly ash, slag, silica fume and double-mixture or three-mixture in deferent age. The results show that the wear value of recycled aggregate concrete mixing 30% fly ash is more than reference concrete at 3days, but can improve final wear-resisting property significantly. The wear value of recycled aggregate concrete mixing 30% double-mixture of fly ash and silica fume is much lower than reference concrete at 3days, and improve early wear-resisting property significantly. The flexural strength of the concrete is 4.26MPa at 3days, which can satisfy the traffic requirement. The wear value of recycled aggregate concrete mixing 30% three-mixture of fly ash, slag and silica fume is lower than reference concrete at 3days, but the declining rate is not significant. It investigates mechanics of double-mixture technique which improves wear-resisting property at the same time.

Crack is one of the major distresses in asphalt concrete pavements, which could significantly reduce the safety and amenity of driving, even the performance of the whole pavement structure. By means of diverse crack repairing manners, the durability and whole service life of the pavement can be improved and extended. After repairing, a composite structure of the repairing system is formed which consists of new crack filling materials and original asphalt concrete matrixes. In order to resist the external loads on the pavement, the composite structure mush work as an integrated structure and maintain sufficient adhesive strength. Therefore, the deformation compatibility of the composite structure is the vital performance for the stability and durability of the entire repairing system. In this study, a modeling analysis for the composite structure under various service conditions was carried out utilizing MIDAS software. The vertical and transverse deformation, transverse and longitudinal normal stress were analyzed by simulating the composite structure under several serving conditions. Based on the results，it was found that the strain, stress and related properties of the repair material and asphalt concrete matrixes could meet the requirements for an asphalt concrete pavement, and the compatibility of the composite structure was also satisfactory.

With the rapid development of Internet, more and more enterprises establish business sites to achieve the purpose of online transactions. Taking taobao.com for example, hundreds of millions of goods trade on the trading platform. In front of the huge commodity image database, extraction of image features is very convenient for people to find out images of user requirement. This paper focus mainly on the color feature of images. Firstly, we segment ROI of images using grabCut algorithm; secondly, we extract primary color of images by using dominant color descriptor of MPEG 7; Thirdly, we adopt RGB color quantization to quantize the primary color. Finally achieve the purpose of image color navigation. I have done experiment to compare with some other methods, and find that the algorithms I adopted make a better performance.

To analyze reclaimed water irrigation effects upon soil quality, including indicators of secondary salinization and heavy metal accumulation, a field experiment in the typical reclaimed water irrigated area (Xin-he irrigated area, Tongzhou District) was carried out in this study. The treated soils for sampling and analyzing were irrigated with reclaimed water and well water. Soil heavy metal contents were determined by ICP-AES, while those of soil salt ions were determined by DX 600. Results show that, reclaimed water irrigated soil has a significant increase in salt ion contents than well irrigated soil, with an increasing order of Na+>K+>Mg2+>Ca2+. And Ca2+、Mg2+、Na+accumulations at 40~80 cm and140~180 cm are relatively critical. Vertical trends of sodium adsorption ratio(SAR) values of soil extraction are the same in districts irrigated with reclaimed water and well water, however, SAR values of reclaimed water irrigated soil are significantly higher than well irrigated soil, with an average of 5~6 times bigger. But values are still in the suitable level for crops. Although heavy metals(Cu、As、Ni、Pb and Zn) slightly accumulate at 140~200cm, values are still consistent with soil environmental standard grade of 1or 2. And contents of heavy metals have no obvious differences between soils irrigated with reclaimed water and well water at 0~140cm.

To improve the machining precision and reduce the geometric errors for 5-axis machine tool, error model and calibration are presented in this paper. Error model is realized by Denavit-Hartenberg matrixes and homogeneous transformations, which can establish the relationship between the cutting tool and the workpiece. The accuracy calibration was difficult to achieve, but by a laser approach, the errors can be displayed accurately which is benefit for later compensation.

The composition and function of vehicle charging system are analyzed, and basic theory of fault tree analysis method is introduced. The qualitative analysis of its reliability is carried out. Fault tree model of vehicle charging system is built, the minimum cut sets are solved and the key parts are found out. Through quantitative analysis, the occurrence probability of top event and importance of bottom event are solved, which provides theoretical basis for fault diagnoses of vehicle charging system, saves time of fault diagnoses and reduces unnecessary disassembly.

In this paper, the amplification to structural non-linear displacement response caused by near-fault vertical ground motions is investigated quantitatively. Based on a set of 30 acceleration records of near-fault ground motions, two typical concrete frame structures, as numerical examples, are examined by means of nonlinear dynamic time-history analysis at two different stages: (1) through the application of horizontal components of acceleration records, (2) through application of the combined horizontal and vertical components at the same time. The numerical results show that the maximum floor-displacements of two concrete frames are limitedly amplified by the vertical effect of near-fault ground motion. On the other side, the maximum inter-story drifts are amplified obviously, and the magnification caused by the vertical effect is about 15%~20% on average. Hence it is evident that the amplification of near-fault vertical effect on horizontal deformation response could not be neglected, and worth serious consideration in future seismic design and evaluation.

Enhancing the accuracy of machine tool is a key goal of machine tool manufactures and users. To characterize the Quasi-static errors and then use software compensation is an important step for accuracy enhancement. The effectiveness of an error compensation scheme relies heavily on the error model. The model must be concise and roust which can be applied to any machine tool. The total Quasi-static errors within the workspace of a five-axis gantry machine tool is composed of geometric error, kinematic error, thermal error. This paper presents an error model which can be used for practical compensation scheme. Homogeneous transformation matrix, rigid body kinematic and small angle approximations are used in this paper for error modeling.

In modern continuing steel bars production pipeline, there are various equipments and automatic controls combining with mechanism, electricity, hydraulic pressure and aerodynamic. This field of fault detection and diagnosis deals with design of computer-based automated system that can assist plant operators. The neural network based expert system have advantages of parallel distributed processing, high robust, fault tolerance, adaptive and self-organization. Applying neural network based expert system for the condition detection and fault diagnosis of steel bars pipeline can reduce the economic loss caused by system downtime.

The lattice constants, total energies and densities of states of Ti, Zr and Hf in ⅣB group with different crystalline structures have been calculated, and the results have been compared with the results of the projector augmented wave (PAW) method in first-principles, CALPHAD and experiments. It is found that the results of lattice stability in this paper agree completely with those of the PAW method in first-principles and agree well with those of CALPHAD. Further analyses of lattice stability from electronic structures show that the crystalline Ti,Zr and Hf with hcp structures have the obvious character of stable phases, but fcc and bcc structures have the character of metastable and unstable phases, agreeing with the results of total energy calculations. It is found from the analyses of atomic populations that the transiton numbers of electrons from the s state to the p and d states for the hcp, fcc and bcc crystals decrease with the increase in elemental period, and the transiton number of electrons from the s state to the p state decrease dramatically, but the transiton from the s state to the d state increase dramatically, leading to much more number of electrons in the d state than that in the s or p state, stronger cohesion or higher cohesive energy between atoms in heavy metals and accordingly the stabler lattice in these heavier metals.

The effect of discharging cycle, voltage, capacitance and time on solidified microstructure of semi-solid slurry of AZ91D alloy treated with Low-Voltage Electric Current Pulse(LVECP) was investigated in this paper. The experimental results show that primary grains of AZ91D alloy were refined apparently, the morphology dendrites of α-Mg were changed by electric current pulse and the nondendritic structure of semi-solid slurry of AZ91D alloy could be obtained with appropriate processing parameters. The decrease of discharging cycle and the increase of discharging voltage and time to prepare semisolid slurry by LVECP discharge promotes the formation of fine α-Mg grains. It is proposed that LVECP treatment created a new dynamic factor for nucleation so that the number of nuclei increased, which restrained the formation of large primary α-Mg dendrites and created a base to form spherical crystals of primary α-Mg. The stronger temperature fluctuation in the melt with many rosette primary α-Mg caused by LVECP discharge and the remelting of the secondary arm roots in the same time are the most important reasons for formation of spherical primary α-Mg grains.

The solidified structure refinement of Al-4.5%Cu under the action of low-voltage pulsed magnetic field (LVPMF) was investigated in the paper. The influences of different pulse voltage and pouring temperature on solidified structure of Al-4.5%Cu alloy were studied. The results show that solidified structure of Al-4.5%Cu alloy can be refined greatly by LVPMF processing. The dendrite growth is restrained and the microstructure is changed from larger dendrite grains to smaller nondendritic grains, and with certain parameters, the equiaxed, non-dendritic grains are gained in the alloy. With the increase of pulse voltage, grain size of the alloy decreases, and the primary phase degrades from developed dendrites into rose-like or spherical crystals. The decrease of pouring temperature enhances the refinement effect of LVPMF processing. With 150 V pulse magnetic field treatment, grain size of the alloy decreases, primary phase degrades and refines gradually with the decrease of pouring temperature.

The rotor of claw-pole permanent magnet generator is constructed by two flangeHs with claw and a ringH of Nd-Fe-B permanent magnet magnetized axially,H axial fluxH is transformedH effectiveH radial fluxH, the polarityH of adjacent claw-poles is opposite, N poles and S poles array alternately. Based on design theory of permanent magnet generator, major parametersH of generator is determineHd. Using equivalent magnetic circuit method, the magnetic path of generator is analyzed, permeance and flux are calculated, thus the claw-pole permanent magnet generator is designed, it possesses high reliability, simple processH and effective voltage-stabilized characteristic.

A new amino acids descriptor E, which (E1~E5) has been introduced in bioactive peptides Quantitative Structure-Activity Relationship (QSAR) Study. It has been proved that correlate good with hydrophobicity, size, preference for amino acids to occur in -helices, composition and the net charge, respectively. They were then applied to construct characterization and QSAR analysis on 48 bitter tasting dipeptides and 30 bradykinin potentiating (BP) pentapeptides using multiple linear regression (MLR). The leave-one-out cross validation values (Q2(CV)) were 0.888 and 0.797, the multiple correlation coefficients (R2) were 0.940 and 0.891, respectively for bitter tasting dipeptides and BP pentapeptides. The results showed that, in comparison with the conventional descriptors, the descriptor (E) is a useful structure characterization method for peptide QSAR analysis. The importance of each property at each position in peptides is estimated by the regression coefficient value of the MLR model. The establishment of such methods will be a very meaningful work to peptide bioactive investigation in peptide drug design.

Laser surface modification, using a continuous wave CO2 crosscurrent laser with generated beam power of 1 kW, was performed on the adamite steel, indefinite chilled cast iron and high speed steel rolls which were applied to the industries. Optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and micro Vickers hardness test were applied to reveal the microstructural details and hardness profiles of the laser treated zone. The results indicate that, laser treated zones of three roll samples consist of melting zone, phase transformation zone and heat affected zone. After laser treatment, the melting zone have low hardness compared to the phase transformation zone, but after tempering at 540°C for 1 hr, the hardness at the melting zone dramatically increases, because of the formation of the fresh martensite from retained austenite. In contrast, the hardness at the phase transformation zone sharply decreases as fresh martensite changed to tempered martensite. There are many small and well distributed FeS and MnS inclusions in the melting zone at the three roll samples.

Teaching quality is a key metric in college teaching effect and ability evaluation. In many previous literatures, evaluation of such metric is merely depended on subjective judgment of few experts based on their experience, which leads to some false, bias or unstable results. Moreover, pure human based evaluation is expensive that is difficult to extend to large scale. With the application of information technology, much information in college teaching is recorded and stored electronically, which founds the basic of a computer-aid analysis. In this paper, we perform teaching quality evaluation within machine learning framework, focusing on learning and modeling electronic information associated with quality of teaching, to get a stable model described the substantial principles of teaching quality. Artificial Neural Network (ANN) is selected as the main model in this work. Experiment results on real data sets consisted of 4 subjects / 8 semesters show the effectiveness of the proposed method.