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Three polyethylene glycol propargyl ethers (PGPEs), namely 4,7,10-trioxatrideca-1,12-diyne (TOTDY), 4,7,10,13-tetraoxahexadeca-1,15-diyne (TOHDY) and 4,7,10,13,16-pentaoxanonadeca-1,18-diyne (TONDY) were designed and successfully synthesized as curing agents for glycidyl azide polymer (GAP). Their structures were characterized by FT-IR, 1H NMR, 13C NMR and elemental analysis, and their glass transition temperatures (Tg) were measured by DSC. The films of GAP cured by the title compounds were prepared via 1,3 dipolar cycloaddition, and then the influences of PGPEs on the Tg, decomposition temperature (Td) and mechanical properties of the films were studied accordingly. The results showed that the Tg of GAP cured by TOTDY and TOHDY were-38.1 oC and-38.2 oC, respectively. The Td of GAP cured by PGPEs was in the range of 235.5 oC - 241.0 oC. The results of tensile tests showed that the maximum stress of GAP films cured with PGPEs were in the range of 0.11 MPa to 0.52 MPa at elongation from 29% to 48%. These results indicated that PGPEs would have potential application in GAP based high energy solid propellant formulations.

An advanced method called internal electromagnetic stirring (I-EMS) was investigated to resolve the engineering problems like coarse-grain, inhomogeneous structure and macrosegregation. The electromagnetic stirrer functioned with internal-cooling was inserted in the melt during DC casting. In this study, a round billet of 2219 alloy DC cast with a diameter of 880mm under I-EMS process condition was produced, and its structure and composition distribution were comparatively characterized. The results show that the mean grain size decreased from the range of 872, 1023, 332 μm to the range of 317, 438, 271 μm at different billet positions with I-EMS. I-EMS consequently produce superior grain refinement and homogeneity. The effect of I-EMS on the grain-refinement and macrosegregation was also discussed.

A layered composite structural model with an outer wear-resistant layer of high-silicon aluminum alloy and an inner layer of ultra-high strength aluminum alloy is designed. A scaling brake drum part with layered composite was prepared by semi-solid precision forming process. The effects of process parameters such as casting temperature, specific pressure, solid layer temperature and heattreatment system on the composite interface were investigated. The results show that the casting temperature and solid layer temperature had a great influence on the interface recombination. The high forming specific pressure could effectively restrain the growth of secondary dendritesof the composite, and the proper heat treatment process could improve the morphology of the composite interface. A scaling brake drum component with A390/7050 layered composite structure was well prepared under optimal conditions.

Compared with SBR latex, waterborne epoxy resin has obvious advantages. The cured epoxy resin emulsified asphalt material has stronger mechanical properties, but it is less used in asphalt modification applications. Aiming at this problem, this paper uses waterborne epoxy resin as the modified material of emulsified asphalt, and carries out performance characterization and road performance evaluation of waterborne epoxy resin modified emulsified asphalt and its mixture under different dosages. Fluorescence microscopic analysis of waterborne epoxy asphalt with a content of 8wt%, 15wt%, 30wt%, and 50wt%, respectively, shows that the resin content should not exceed 30wt% to ensure the performance of asphalt. The bonding properties of SBR modified emulsified asphalt and waterborne epoxy resin modified emulsified asphalt with different dosages at 20 °C and 60 °C were analyzed. The results show that the tensile strength and oblique shear of waterborne epoxy modified emulsified asphalt. The strength is higher than SBR modified emulsified asphalt, and its high temperature resistance is better than SBR modified emulsified asphalt material. The road performance analysis was carried out on the mixture prepared by the aqueous epoxy modified emulsified asphalt with the content of 0wt%, 8wt%, 15wt% and 30wt% respectively. The results show that with the increase of waterborne epoxy content, the Marshall stability, splitting strength and high temperature rutting resistance of the mixture increase more obviously. The freeze-thaw splitting strength of the waterborne epoxy resin mixture is 13% higher than that of the pure emulsified asphalt mixture, and the splitting strength is also significantly improved. Due to the high stiffness of the waterborne epoxy resin after curing, the maximum bending strain of the mixture is reduced, and the recommended dosage is not more than 30% by weight. On the whole, the introduction of waterborne epoxy resin could greatly improve the strength and road performance of the asphalt, and could be used as a proper road repair material.

To obtain fine microstructure and homogeneous distribution of alloying elements in the large-sized billet, the internal electromagnetic stirring as a new electromagnetic stirring method was proposed and utilized for the preparation of Ф508 mm 7050 aluminum alloy billet. The results demonstrate that the internal electromagnetic stirring could refine the microstructure and second phase, and alleviated the macrosegregation significantly. The grain size at the edge, 1/2 radius, and center of the billet decreased to 180 μm, 175 μm, and 185 μm, respectively. Moreover, the relative macrosegregation of Zn, Mg, and Cu at the edge and center decreased to 3.9% and 2.8%, 2.3% and 1.6%, 4.1% and 2.5%, respectively.

Large-sized 2219 aluminum alloy ingot has wide application prospect in aerospace and military fields. Severe defects, such as coarse grain, the inhomogeneity of structure and macrosegregation occurred in large-sized aluminum ingot produced by normal DC casting. The application of a single magnetic field in DC casting process cannot solve these defects. In this paper, a new method with the combination of electromagnetic fields imposed on bulk melt treatment during DC casting was proposed. And a φ508 mm ingot of 2219 aluminum alloy was prepared in this method. Compared with the normal DC casting, the effect of the combined electromagnetic fields on the microstructure and properties was studied. The experimental results demonstrate that the application of the combined electromagnetic fields significantly refines the grains, and the grain size distribution on the cross section of the ingot tends to be more uniform as well as the mechanical properties are significantly improved. The microstructure and grain size distribution can be significantly affected by different combined electromagnetic fields. It is considered that the appropriate combined electromagnetic fields parameters play an important role in controlling the homogeneity of large-sized ingots.

Uniform direct chill (UDC) casting is coupled annular electromagnetic stirring and intercooling, having been utilized for the preparation of large-sized aluminum alloy billet. In this paper, the UDC casting was applied to 2A14 aluminum alloy billets with a diameter of 584 mm. Hot compression tests, cogging and ring rolling procedures were carried out for the billets, respectively. The results show that during the deformation temperature of 420 °C and the strain rate of 0.01 s−1 to 10 s−1, the flow stresses of different positions are higher and more stable in the UDC casting billet than in the normal direct chill (NDC) casting billet. The dislocation glide is the dominant deformation mechanism of 2A14 aluminum alloy. Meanwhile, the UDC casting significantly improves the mechanical properties of the rolled rings in tangential and axial directions compared with the NDC casting.

Lots of waste rubber is being produced in the world and the utilization of it not only mitigate environmental impacts caused by waste rubber disposal but also enhance sustainable development. As a result, rubberized concrete, by incorporation of waste rubber into concrete, should be considered as one of the effective strategies to take advantage of waste rubber. However, problems such as low strengths, weak adhesion between rubber particles and cement pastes, and undesirable pore structures associated with rubberized concrete should be pay more attention to. In this study, the effect of replacement fine aggregate with rubber particles on rheological and mechanical properties of concrete containing CaCO3 nanoparticles was examined through slump, compressive and flexural strength tests. Rubber particles were employed to replace the fine aggregate equally by volume while CaCO3 nanoparticles were used as an equal part of binder by weight. Different sizes and volume contents of rubber particles were evaluated as well as different weight contents of CaCO3 nanoparticles. In addition, corresponding tests were also performed to evaluate the effect of CaCO3 nanoparticles in comparison to concrete specimens without CaCO3 nanoparticles. The results showed that replacement fine aggregates with rubber particles had some influence on the mechanical properties of rubberized concrete, resulting in undesirable findings in terms of compressive and flexural strengths. However, the incorporation of CaCO3 nanoparticles improved mechanical properties of rubberized concrete. Regarding slump test, the rubberized concrete without CaCO3 nanoparticles showed better performance. Considering rheological and mechanical properties, rubberized concrete with 1% CaCO3 nanoparticles presented acceptable results.

Chloromethylated polysulfone (PSF-Cl) porous microspheres were prepared with non-solvent induced phase inversion method for the immobilization of acidic ionic liquid ([MIMBS][HSO4]). FT-IR, SEM, and 1H-NMR were used to characterize the structure and property of polysulfone porous microsphere supported ionic liquid (PSF-ILs). The results showed that acidic ionic liquid was supported onto the PSF-Cl porous microspheres by covalent bond. Furthermore, the catalyst exhibited a good catalytic activity with about 57% acetic acid conversion rate after 8h reaction. After the catalyst was reused for 7 times in the synthesis of ethyl acetate, the yield only decreased 6%.

Self-locking clamping device is an important part of self locking wind power hydraulic cylinder. When the wind power system is shut down, the hydraulic cylinder must be reliably locked. This paper mainly studies the principle of self-locking device, the calculation of clamping force, the performance factors and the analysis of the elastic deformation force of the lock ring in order to meet the performance requirements of hydraulic cylinder in the process of wind system lock.

A new type of multi-footed wheel walking system is designed to break the limitations of the existing walking system. The multi-footed wheel can be used in a variety of complex terrain and can better protect the vegetation on the ground. In this paper, we established a mathematical model and analyzed the mechanics theory of the multi-footed wheel. At the same time, structural analyses of key parts were done using workbench and the rationality and safety of the structure was verified by the studies above.

This article presents as follows the most recent progresses of our group on in-situ characterization and evaluation of the molecular mechanisms of interfacial interaction of minerals and bioleaching microorganisms. (1) By studying the speciation transformation of iron/copper/sulfur on the mineral surface, the evolution of cell surface properties and EPS composition, the evolution of microbial community structure, and the evolution of expression of key oxidase genes during bioleaching, to characterize the adaptation process and therein the effects of it on the specific sulfur oxidation efficiency of bioleaching; (2) by in-situ characterization of the evolution of chalcopyrite surface microstructure, chemical speciation and the biofilm formation, to illustrate the specific adsorption and the relationship between cell growth/biofilm formation and the structure and speciation on the defect mineral surface; (3) by studying the utilization, transformation and activation of S0, which is one of the major intermediates during bioleaching, and the distribution of extracellular thiol groups and iron speciation, to evaluate in situ the sulfur activation mechanism; and (4) by comparative proteomics study of the extracellular and outmembrane proteins and looking up the genome sequence, to screen sulfur activation/transportation relevant proteins and genes.

The effects of triethanolamine on the compressive strength and setting time of fly ash cementitious materials, slag cementitious materials, and limestone cementitious materials were investigated. The results show that the dosage of 0.04% of triethanolamine can significantly improve the 3d, 7d and 28d compressive strength of fly ash cementitious materials. It possesses less impact on the setting time. The dosage of 0.04% of triethanolamine can significantly improve the 3d and 7d compressive strength of slag cementitious materials while the effect of late strength is not obvious. It extends the initial setting time and the final setting time is not changed, which has retarding effect. The results of hydration heat and XRD show that triethanolamine extends the induction period of cement hydration, and gypsum is exhausted in advance during the hydration process. Triethanolamine promotes the transformation of AFt to AFm and there is no effect on the type of hydration products.

In order to investigate the early hydration behavior of rapid setting and hardening belite sulfoaluminate cements, the methods of X-ray Diffraction, Scanning Electron Microscope, Compressive Strength test and Setting Times test were used to identify and quantify the hydration kinetics and microstructure of this new-found cements in China. The results showed that the main mineral compositions of high belite sulfoaluminate cement clinker included calcium sulfoaluminate (4CaO·3Al2O3·CaSO4), belite (2CaO·SiO2), ferrite phase, free gypsum and free lime. It was found that not only the setting time and compressive strength but also the composition of hydration products were influenced by anhydrite to some extent. Meanwhile, a mass of AFt and AFm generated along with the hydration process at different ages, overlapped, crossed and penetrated through calcium silicate hydrate gel and aluminum oxide to form a relatively dense structure which could contribute to the high strength of cement.

Two intermediate thermal mechanical treatment (ITMT) Processes were designed for investigation the influence of multi-scale precipitated particles on microstructure evolution during thermo-mechanical processing of Al-7.6Zn-1.5Mg-1.75Cu-0.12Zr alloy by hot compressive experiments and microstructure testing of OM and EBSD. It is found that the size and distribution of precipitated particles preprocessed by over-aging at 400°C for14h can meet the particle stimulated nucleation of recrystallization. Refined and uniform grains present in the sample after hot deformation at about 20 of LnZ up to 80% reduction and subsequent final solid solution treatment. But for samples preprocessed by solid solution at 435°C for 2h and aging at 200°C for 12h, Refined uniform recrystallized grains or recovery sub-grains in elongated grains present in the samples after hot deformation at about 25 of LnZ up to 60% reduction followed by annealing at 350°C for 0.5h and final solution treatment.

Zirconium diboride nanopowders were synthesized by sol–gel method using different zirconium sources of zirconium carbonate and zirconium nitrate based on different gelling processing. Both of zirconium source can be applied in the synthesis of good performance ZrB2 powders while the in-suit sol-gel using zirconium carbonate tend to form the spherical ZrB2 powders about 50nm and the traditional sol-gel using zirconium nitrate prefer to form worm ZrB2 powders about 200nm. The influences of B/Zr molar ration of zirconium carbonate and zirconium nitrate of sol-gel method on the phase constitution was investigated. And the gel mechanism was discussed to explain the different phase constitution, morphology of final products.

This article presents the progress on characterization of the interfacial interaction between sulfur oxidizing microbes and sulfide minerals by using of synchrotron radiation-based techniques including S/Fe/Cu X-ray absorption near-edge structure spectroscopy (XANES), X-ray Diffraction (XRD), micro-X-ray fluorescence (μ-XRF) mapping and micro-scanning transmission X-ray microscopy (μ-STXM) imaging, together with other accessory approaches such as SEM/EDS, Raman spectroscopy, FT-IR spectroscopy, and electrochemical methods as well as comparative proteomics methodology.

Differential utilization of isomers pyrite and marcasite by Acidianus manzaensis were comparatively studied, besides the iron and sulfur speciation transformation of the minerals was also investigated based on synchrotron radiation X-ray absorption near edge structure (XANES) spectroscopy. The results showed that the biooxidation of pyrite was faster than marcasite. The bioleached surface of both pyrite and marcasite are serious corroded, and the Fe (III)-containing species as well as jarosite were gradually produced, and more elemental sulfur species were formed on the marcasite surface than that for pyrite. It demonstrates the mineral structure does affect the biooxidation of pyrite and marcasite, and the more precipitated elemental sulfur might be one of the reasons leading to lower oxidation rate of marcasite by A. manzaensis.

The bioleaching experiments of chalcopyrite were conducted with single and mixed mesophiles (30 °C) and moderate thermophiles (45 °C) and extreme thermophile (65 °C), respectively, and analyzed by synchrotron radiation (SR) based X-ray diffraction (XRD) and X-ray absorption near edge structure (XANES) spectroscopy. The results showed that the copper extraction of chalcopyrite could be significantly promoted by bioleaching microorganisms, and the promotion effects for both the mixed cultures grown at different temperature and the different cells grown at the same temperature were significantly different. The surface of chalcopyrite after bioleached by the mixed or sole cultures are serious corroded and became complicated. More S0 was found to form in the sole cultures of specific iron-oxidizing microorganism L. ferrooxidans and L. ferriphilum and sulfur-oxidizing microorganisms A. thiooxidans and A. caldus cultures. Jarosite and secondary minerals (chalcocite and covellite) were detected for the mixed cultures and sole cultures of iron/sulfur-oxidizing microorganisms. The evolution of chalcocite and covellite were just relevant to the potential of leaching solution, no matter which cultures were used, where chalcocite could be formed at Eh value less than 500 mV and then converted to covellite at Eh value ~550 mV.

The in situ relevance of micro- structure and electrochemical properties of chalcopyrite to adsorption of thermoacidophilic bioleaching Archaea Acidianus manzaensis was studied. In this study, the electrochemical behavior of chalcopyrite was first investigated by cyclic voltammetry (CV) to get suitable initial reduction and oxidation potentials, at which electrochemical corrosions of chalcopyrite for several time were performed, respectively, to get specific surface micro-structures. The specific adsorption of A. manzaensis on the electrochemically corroded chalcopyrite surface was then comparatively studied. The changes of microstructure and chemical composition/speciation on the surface of chalcopyrite before and after electrochemical treatment and bio-adsorption was characterized by scanning electron microscopy/electron dispersive spectroscopy (SEM/EDS), and synchrotron radiation-based X-ray diffraction (SR-XRD) and Fe, Cu K-edge X-ray absorption near edge structure (XANES) spectroscopy. The results showed that the suitable initial oxidation and reduction of chalcopyrite electrode were at 0.67 V for 1h and -0.54 V for 10 min, respectively. After treated at 0.67V the surface of chalcopyrite became Cu-deficient with a composition of CuFe1.02S2.15, and bornite (Cu5FeS4) was detected. While after treated at -0.54V, the surface became Fe/S-deficient, with a composition of CuFe0.33S0.81, and a mass of chalcocite and some covellite were detected. Comparing to the original chalcopyrite, the adsorption capacity of A. manzaensis was increased on the surface of oxidation-treatment at 0.67 V, and decreased on the surface of reduction-treatment at -0.54 V. It clearly demonstrates the bornite-containing copper deficient chalcopyrite surface was more preferably adsorbed, whereas the chalcocite-containing Fe/S deficient chalcopyrite surface was less adsorbed by A. manzaensis, indicating the dependence of the specific adsorption of A. manzaensis upon the secondary minerals as well as Fe/S availability in the microstructure of chalcopyrite.

With honeycomb lattice ofsp2hybridized carbon atoms, graphene has demonstrated excellent electrical and mechanical properties. One of its promising applications is to fabricate graphene-ceramic composite to improve the mechanical properties. In order to quantify the strength between graphene-ZrB2interactions, molecular dynamic method was utilized to simulate typical interface of graphene/ZrB2ceramic structure. Berendsen method was used to control the temperature and pressure during the whole simulation process. Universal potential function was employed to simulate the force filed between graphene and ZrB2structure. The binding structures of graphene/ZrB2(0001) interface were analyzed in detail and the bonding energy of the interface was calculated. The influence of numbers of graphene layer and sandwich structures on the bonding energy of interface is discussed. The study helped to understand the influence of graphene on mechanical properties of ZrB2ceramic.

Mechanism of CNT-metal bonding is investigated using molecular dynamics in this study. Both bonding and debonding process are considered. It is shown that the bonding can be achieved at a temperature lower than the melting point. The surface melting and capillary wetting dominate the bonding process. In addition, there are two potential failure positions, one is at CNT-Ni interface and the other is at nickel surface which are determined by the strength competition of these two interfaces. To obtain high bonding strength we should form coalescence structure between CNT and the metal at a higher temperature to achieve larger contact length. Also we find that the debonding process experiences elastic deformation followed by debonding at CNT-Ni or Ni–Ni interface.

The effect of alloying elements, heating rate and quenching temperature on the hardness of steel 42CrMo after induction hardening were investigated by thermal simulation tests, hardness tests, optical microscopy (OM) and scanning electronic microscopy (SEM). The steel No.2 was obtained by adding 1.49% Ni and reducing 0.32% Cr in steel No.1. Experimental results show that the hardness of steel No.1 decreases while that of steel No.2 slightly increases under the quenched temperature of 900 °C when the heating rate increases from 100 °C/s to 300 °C/s. When the heating rate is 300 °C/s, the hardness of steel No.1 increases sharply with the elevating of the quenched temperature. However, the hardness of steel No.2 increases gently with the quenched temperature increasing below 900 °C but keeps constant above 900 °C. It is interesting that the hardness of steel No.2 is obviously higher than that of steel No.1 under the same heating process. This phenomenon can be attributed to the following aspects: firstly, the Ac1 and Ac3 temperatures can largely decrease and the dissolution of carbide proceeds further; secondly, the addition of alloying element and the dissolution of carbide in the austenite can improve the hardenability of steel and thus increase the volume percentage of martensite in the quenched microstructure; in addition, the quenched microstructure of steel No.2 is finer than that of steel No.1 which undoubtedly helps the increase of hardness. In consideration the disadvantage of higher quenched temperature and heating rate, it is comprehensive to determine the quenched temperature as 900 °C and heating rate as 100 °C/s in order to increase the hardness of steel No.2.

Through the Merlot wavelet periodic analysis and Mann-Kendall mutation analysis about the maximum wind speed of 14 weather station in Hexi corridor over the past 41 years,the evolution characteristic of the maximum wind speed can be gotten:the Hexi corridor has about 28-29 years main period and 8-12 years secondary period,presenting sinusoidal curve,and the transformation energy cycled from small to big to small to big;After 1980,there were abrupt changes and decline in Anxi,Jiuquan,Zhangye and Wuwei.The Hexi corridor is in the wind speed environment of same climate conditions,and the inter-annual change feature becomes balanced; but in internal local areas,due to the influence of environment, terrain and urban heat island effect,the secondary period is different,presenting abrupt changes and decreasing tendency in 1980s.

Aluminum cables are playing an increasingly important role in power transmission system, in which the “rare-earth high-iron aluminum alloy power cables were developed in China. In this paper, the effects of B on grain refinement of high-iron aluminum alloy were studied by using OM (optical microscopy), SEM (scanning electron microscopy), EDX (energy dispersive X-Ray spectroscopy) and XRD (X-ray diffraction). And the conductivity of high-iron aluminum alloy was also tested. The results showed that B could take significant effects on grain refinement and promote the increase of conductivity. The refinement may be mainly due to the eutectic reaction in solidification process and the formation of AlB2 particles. The optimal concentration of B was determined as 0.06 wt. %.

At present, digital printing technology develops rapidly, but in terms of color reproduction, digital proofing and the traditional mechanical proofing are different, it’s difficult to determine the color reduction according to the dot size, mainly manifested in the difference between the display color and the actual digital output color. In this paper, through analyzing the differences with color management technology, to keep consistency between the original display color and digital proof color as the goal. Through the study, mainly provides solutions for color consistency of digital proofing for paper packing.

The scale-inhibition effect of electromagnetic field was tested on circulating cooling water of power plant, and then the scale sample was analyzed by SEM and XRD. The results showed that, under optimum scale-inhibition conditions, aragonite content increased and calcite content decreased, and scale-inhibition rate was up to 78.2%; under the poorest conditions, both aragonite and calcite crystals existed, and the scale-inhibition rate was-201.0%; after treating with electromagnetic field, size of both calcite and aragonite particles decreased, making them more easily flown away and thus showing better overall scale-inhibition effect; when energy provided by the electromagnetic field was more than the decrease in free energy of the system, extra energy turns the calcite CaCO3 into other forms of metastable crystalline phases, then content of different crystalline phases is changed in favor of scale inhibition.

As an indispensable part of renewable energy power generation system, energy storage to a large extent, has resolved randomness and fluctuation of photovoltaic power generation and enabled its smooth output. Firstly, a method of energy management by means of LabVIEW was proposed. Based on its advantages on data collection and convenience of hardware integration application, this software was used to conduct real-time surveillance and control of such parameters as charge-discharge current and DC line voltage. Then, five operating mode were raised on the basis of generating capacity of photovoltaic cell and surplus capacity of energy storage battery , insure quick response and high-efficiency operation of the system. Finally, the effectiveness of energy management proposed method was verified on the built experimental platform.

Automatic white balance algorithm (AWB) is significant for color temperature restoration of digital imaging system. According to the limitations and disadvantages of existing traditional white balance methods, in this paper a new AWB algorithm for airborne camera is proposed. Using RGB and histogram information divide the input image into different color character regions; according to the color richness level, adopt different white balance algorithms to achieve chromatic aberration adjustment. Experiment results show the effectiveness of the proposed AWB algorithm for airborne camera.

The probability distribution of electrical characteristic parameters of semiconductor device is an important reference which is used to analyze the reliability and quality consistency of devices. These distributions are considered as normal distribution at home and abroad. This paper utilized mature GaAs MESFET low noise amplifier as analytic sample which is volume production and wide application, and used high-precision Agilent B1505A device analyzer to test main electrical characteristics of 408 samples. After the distribution generation of test results, the Skewness-Kurtosis method was used to analyze probability distributions of the results. At last, the conclusion of distribution of measuring parameter is non-normal distribution was educed.

Pedestrian Dead Reckoning (PDR) is a core component in pedestrian navigation. Usually, PDR algorithms use the current position and movement information to figure out position in the future in order to accomplish the navigation task. Step detection, as a basic portion of PDR, is significant for the implementation of Pedestrian Navigation. In this paper, a step detection algorithm is designed based on the existing research in the relative area. To improve accuracy, the algorithm involves a Fast Fourier Transformation (FFT) for optimizing. At last, an experiment is conducted for this algorithm, and the error rate of step detection is less than 1%.

In order to classify the objects in nature images, a model with color constancy and principle component analysis network (PCANet) is proposed. The new color constancy model imitates the functional properties of the HVS from the retina to the double-opponent cells in V1. PCANet can be designed and learned extremely, which comprises only the very basic data processing components: cascaded principal component analysis (PCA), binary hashing, and block-wise histograms. At last, a SVM is trained to classify the object in the image. The results of experiments demonstrate the potential of the model for object classification in wild color images.

The key technology of electric vehicle battery management lies in the battery state of charge (SOC) estimation, accurate and efficient estimation of SOC can provide the reference data for the control system of the electric vehicle in time. On the basis of the Ah measurement method, Calman filtering method, open circuit voltage method to estimate method, the estimation procedure to estimate the charged battery optimized Calman filtering method, effectively shorten the calculation process, improve the estimation accuracy, in the normal operation of electric vehicles under the influence of comprehensive consideration about the discharge voltage, battery temperature to estimate the state of charge, the Calman filter optimization algorithm, and its application in the electric vehicle battery management system. The experimental results show that, the algorithm can calculate the real-time high charge state of surplus value, provides a set of effective estimation scheme of calculating the battery charge state.

5183 welding wire micro-alloyed using Sc, Zr, Er and automatic MIG welding system applied to weld 7A52 aluminum alloy. Optical microscope and universal tensile testing machine utilized to investigate microstructure and tensile property of welded joint, respectively. The results indicated that welded zone and fused zone was composed of uniform isometric crystal and tiny isometric dendrite crystal when the welded joint was fabricated by using 5183 welding wire micro-alloyed via rare earth element, respectively. Tensile strength and specific elongation of welded zone was improved utmostly when the 5183 welding wire micro-alloyed treatment via single Sc or Zr, respectively. Owing to mirco-alloyed treatment of 5183 welding wire by using Sc, Zr or Er, a large number of Al3Sc, Al3Zr, Al3Er granules had generated in micro-poll, which played heterogeneous nucleation role and refined microstructure of welded zone. Meanwhile, there emerged nanoscaled A13Sc, A13Zr, Al3Er strengthening phase dispersed in welded zone, which had led welded joint to exhibit exclent tensile strength.

In this paper, based on the practice optical transport network (OTN) electric power communication network business, through the modeling analysis shows the specific influence dispersion optical pulses, then discussed the dispersion compensation technology, through modeling and simulation analysis of the dispersion compensation fiber (DCF) and dispersion compensation module (DCM), at the same time with reference to its OTN equipment dispersion tolerance, form a light layer of dispersion compensation quantity calculation method of the experience and grid OTN networking dispersion compensation scheme, reduce the effects of dispersion as far as possible.

Frequency diversity scheduling allocates whole system bandwidth to a user in order to conquer deep fading of the sub-band when user with high-mobility. Though OFDMA technology mitigates interference of users in same cell, it increases interference of cell edge user as base stations use same frequency. Thus, we developed a frequency diversity fairness scheduling algorithm to balance fairness of cell center user and cell edge user. It is demonstrated by computer simulation that the proposed algorithm increases user fairness of the system with same system throughput and fairness between cell edge user and cell center user. It also points out that the algorithm proposed has the same complexity with the frequency diversity scheduling algorithm.

Water scarcity is a critical issue in most regions of China; however, river basin groundwater monitoring is extremely limited.This study evaluates the ability of the GRACE satellites and Global Land Data Assimilation System(GLDAS) to monitor groundwater storage in the Yellow River Basin and Yangtze River Basin, China, which is subjected to intense irrigation, production and living. The simulated terrestrial water storage change data which was calculateed by Global Land Data Assimilate System was used to compare the accuracy of GRACE data. Results show that both two datas show significant seasonal cycle in the Yangtze River and Yellow River (except frozen soil), the correlation is 0.89 and 0.84(p

Arc suppression coil has been applied widely in power system.It focuses on the fault that arc suppression coil often appears in the process, and divides to the nature of the faults. We also take corresponding treatment methods for different faults at the same time. This article introduces the failure processing methods of the arc suppression coil in detail, expounding respectively that the general failure processing methods, the abnormal failure processing methods of arc suppression coil, the action failure processing methods and the discontinued failure processing methods.

Power communication network traffic prediction is important basis of safely assigning and economically running. The forecasting precision will directly affect the reliability, economy running and supplying power quality of power system. Paper first expounds the electric power communication network traffic prediction research present situation, summarized the characteristics of the forecast and the influencing factors, summarizes the commonly used method, is put forward to the return of the electric power communication network traffic based on libsvm prediction method, and the PSO (particle swarm optimization) algorithm is adopted to model parameters optimization, with the test set error as the decision, based on the optimization of model parameters, choice, makes the prediction precision is improved.

Design the mechanical structure of automatic CNC grooving and bending machine based on the modular design method, and the three-dimensional mechanical structure model is created out using Pro/E; design the control system of automatic CNC grooving and bending machine based on the open CNC system theory, the control structure takes PC and motion control card method, and the control software is developed by Visual C++ 6.0. Finally the automatic equipment has been developed which has advantages of automatically processing, high precision and low price.

This paper researched the power generation characteristics of PV module by a variety of environmental factors through building a simulation model. Based on this module, it analyzed the effect of environmental factors, such as temperature, light intensity, dust deposition and other factors when the PV module operating respectively. Then, author compared the simulation data with the distributed PV system operating data in Shanghai to verify the reliability of the model. On the analysis of these data, this paper deeply researched the PV module output power and the variation of the attenuation characteristics.

While the system is equipped with Petersen coil caused by the switching operation can prevent a different period , single-phase disconnection and other factors neutral point displacement , so that the neutral point voltage is too high, the threat of insulation safety equipment . Also in the normal operation of the power grid , but also effectively prevent resonance over-voltage , prevent system damage caused thereby , better protection of system security , stability, and high-quality operation. Summary of small current grounding system after the formation of arc suppression coil compensation compensation network system , in order to better prevent arc short-circuiting the system of single phase , which is to ensure security of supply , improve reliability and power quality .In the paper, small current grounding system Petersen coil with the compensation adjustment is carried out and some analysis, study and research is done in order to improve the operating personnel awareness and emphasis on small current grounding system , and better ensure the safety of the small current grounding system , stable operation.

This paper introduces the process of the nonlinear finite element model which is established by using ABAQUS software, and introduces the characteristics of ABAQUS software, meanwhile, lists the constitutive relation of steel pipe, steel and concrete, finally introduces some experimental model.

Through the analysis of harmonics caused by transformer, capacitor, electromagnetic voltage transformer and other accident, harmonics is an important indicator of power quality, which has been included in the “pollution" of power grid is found. In order to understand the harmonic, this paper from the concept of quality of electric energy, and then gradually extended to the field of harmonics. This paper firstly introduces the various reasons and equipment may produce harmonic, Secondly, illustrate harm of harmonic to operation of transformers, capacitors, electromagnetic voltage transformers and other electrical equipment, let more people know and understand the relevant knowledge of the harmonic, In order to save technical force and provide scientific basis for future effective harmonic.

In this paper, we do the research on the steel tube filled with steel-reinforced concrete subjected to axial compression after high temperature by changing the temperature and the slenderness ratio.The influence of the temperature and slenderness ratio on the composite column and its stability formula of the composite column after high temperature was gotten by the research.

Based on properties of high-speed railway bridge and rail system restraints, the rail-bridge model is established by considering CRTS II unballasted track and bridge structure. The results show that the effect of CRTS II system restraints on seismic response for multi-span simply supported girder bridge is greater so the rail-bridge model should be adopted in earthquake response analysis. Due to the effect of longitudinal stiffness of the railway and bridge transitional section such as terminal spine, the more significant is unloading for seismic response of the side piers if the fewer is the number for the rear-structure spans.

The internal flow field and the noise of inlet blocking fault and trouble-free for control valve are numerical simulated by CFD. The study shows that it is a greater influence on the internal flow field by inlet blocking, the back-end of stemming appears reverse flow, and it make vortex, the phenomenon of the two fluids mixing is appeared below the valve core. The tremendous noise is appeared in the blocking, and it increases the noise of the surrounding area.

They rarely involve deep-seated score analysis in the existing teaching management software, Therefore, we can not evaluate science teaching, Based on this, This article uses the Struts framework and Hibernate framework to design Student Performance Analysis System based on MVC pattern, it Proposed optimization algorithm based on standard score, We can achieve student achievement statistics and analysis with it, This algorithm can better reflects relative position that the individual is in groups, and has a certain scientific. Experimental results show that the system has a good safety and openness, and provides support information for academic departments to promote better teaching work, and finally improve the quality of teaching.

The flow characteristic and differential pressure-flow of inlet blockage fault and trouble-free for control valve are numerical simulated by CFD. The study shows that relative gain of flow characteristic curve for inlet blockage is increased, and it enhances the influence on fluctuation to flow change. The flow is less than the trouble-free at the same pressure, and with the increase of the differential pressure, flow difference of comparing with trouble-free increases gradually.

With the popularization and promotion of the Internet, ASP.NET has gradually become the mainstream of development platform for WEB application. At present, most colleges and universities have opened the door for students majoring in computer courses. Because of the complex of ASP.Net teaching and the teaching target key requirement to cultivate the students’ ability of practice, the traditional mode is not applicable to the teaching of Theory of teaching. So, this article made based on the project - driven ASP.Net Teaching. By teachers in selecting suitable project topics, the teacher according to the project needs to explain the knowledge of ASP.NET and ultimately by the students to complete the design and development of the entire project in teaching. Practice has proved that the project-based driving teaching method for students’ active learning teaching content and improve students' ability to analyze and solve problems.