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With the rapid development of China's economy, an unprecedented breakthrough is also achieved in the urbanization construction speed. This paper first introduces the principle of method for evaluation of urbanization, then selects the indicator system of urbanization in Xianning mountain, and builds up a set of indicator system for evaluation of urbanization in mountainous area in Xianning with AHP, conducts a fuzzy comprehensive evaluation of urbanization of mountainous area in Xianning; finally, the evaluation result is analyzed.

The microstructural evolution of of as-cast ZK60 magnesium alloy processed by cyclic extrusion and compression (CEC) were studied, and the effects of technical parameters on microstructural evolution were investigated. The results show that the grains of as-cast ZK60 magnesium alloy were obviously refined and uniformed by CEC, the average grain size was decreased from original 50 ~ 60 μm to about 2 μm when the extrusion ratio was 8 with 8-passes at 350°C, and the refinement effect was increased with the rising of extrusion ratio and passes. The effect of increasing passes on grain refinement was not obvious when it exceeds 8. Nevertheless, it is beneficial for the grain homogenization.

Because of the extensive use of thin sheet metals to reduce the weight of vehicles, wrinkling is becoming a more common and one of the most undesirable failures in the sheet forming process. Generally, experiments for studying wrinkling phenomena can be divided into two methods: actual forming of typical parts such as annular cup test on the one hand and the tests of specially designed sample geometries like the Yoshida Buckling test on the other. Recent experiments indicate that the plastic strains at the onset of wrinkling in the Buckling Test with Yoshida samples are too small to reflect reality of deep and stretch drawing conditions. Therefore, in this paper, in order to enhance the accuracy of the prediction of wrinkling, a new modified Yoshida specimen is provided for numerical simulation. The fundaments of the different buckling phenomena are going to be explained considering the energy theory in metal forming processes. Meanwhile, the influences of the changeable sample geometries in order to cause different stress distribution within loaded area of specimen have been investigated.

To study effects of binders on storage stability of the silicon delay composition, sample B and C1 were prepared separately by adding shellac and fluororubber(FPM2602) in basic formula A, and sample C2 and C3 were prepared by changing adding amounts and modes of fluororubber respectively. On conditions of 71°C and 92% humidity variation rule of burning rate and delay precision varying with time was studied. The results indicate that binders have function of “heat sink”, and reduce burning rate and delay precision of the delay composition, especially the effects of shellac are obvious. Under two kinds of storage conditions, sample B adding with shellac can obviously improve agents influenced by temperature and humidity. Increasing fluororubber contents the delay composition can also be improved influenced by temperature and humidity. Binders at constant amounts, fluororubber solution in adding directly to the composition in mixing process can improve the delay precision.

To study sudden expansion flow, it took N-S equation described by stream function as governing equation and got discrete equations with upwind difference and central difference. The discrete equations are applied to calculate sudden expansion flow. The results showed that when the Reynolds number is lower, stream function distribution calculated with central difference is similar to with upwind difference and that when the Reynolds number is higher, the calculation with central difference becomes unstable, even not converged. It showed that for sudden expansion flow, the upwind difference can simulate well and the results are satisfied

In rock and soil media, seepage and stress fields are interacting and interrelated system. Analyzing on mechanism of seepage field acting on stress field and on mechanism of stress field acting on seepage field in rock and soil media, it established mathematical model of seepage field with stress field acting on and mathematical model of stress field with seepage field acting on. According to coupling mechanism, it gave mathematical model of coupling seepage field and stress field and corresponding steps of FEM

Through the analysis of traditional forward and backward substitution method, put forward an advanced algorithm of power flow calculation applied for the radial distribution network. This method optimizes the numbered embranchments, nodes, branches, uses directly the branch impedance parameter and the given power of the end node to calculate the voltage and power distribution, And use MATLAB to compile power flow calculation program, which is proved to be feasible by an example.

With the continuous development of online shopping, a day will generate tens of thousands of consumer records. E-commerce sites want to recommend the consumers that they may be interested in the products by analyzing the consumer historical consumption data. However massive consumer records led to recommendation speed getting slow by using the traditional personalized recommendation algorithm. By researching on the collaborative filtering algorithm based on ALS and the MapReduce parallel programming model, we explore parallelization of collaborative filtering algorithm based on ALS. The experimental results show that the algorithm in this paper can improve the computing efficiency.

This paper summarizes the reactive power optimization of power system characteristics and requirements, proposed to target the active power loss of reactive power optimization mathematical model, And the traditional classical algorithm can not handle the limitations of discrete variables, using the adaptive particle swarm optimization algorithm to solve the problem of reactive power optimization. By testing on IEEE30 bus system simulation, comparing different algorithm optimization results show the effectiveness and superiority of APSO algorithm.

This paper is about dynamic simulation of the belt conveyor based on ADAMS and PRO/E, and analyzes the influence of the transport distance of the conveyor start-up. As the transport distance of belt conveyor increases, the time of which start-up speed increases from rapidly to slowly prolongs, and the lateral vibration of the belt is more severe. It provides a basis for the selection of start-up time and idler spacing.

Electrokinetic remediation is an effective technology to enhance bioremediation of oil-contaminated soil as the transport process of non-polar organic contaminants in soil was promoted under low-power direct current electric fields. In this study three treatments including the application of electric field treatment alone, inoculation treatment alone, and combination of the application of electric field and inoculation treatment were carried out. The results indicated that highest removal efficiency was 83% in couple of the application of electric field and inoculation treatment. TPH concentration decreased from 6000 mg.kg-1 to 2000 mg.kg-1 when a 30 voltage direct current electric field was applied to oil-contaminated soil for 10 min after 4 days. It was observed that dehydrogenase activity had no increase after application direct current electric field. However, the TPH degradation efficiency was 52% higher than the control treatment. GC analysis showed that n-alkanes (C14-C31) were preferentially degraded, and soil remaindered more low quality compounds after the application of electric field treatment applied 52 days. These results indicated that the application of electric field improved degradation of inoculated bacteria through promoting the transport of nutrients, such as nitrogen and phosphorous and electron acceptors.

The paper presents a simulation platform for the development of vehicle adaptive cruise control (ACC) systems. The simulation platform has the ability to simulate traffic driving conditions and critical driving conditions and covers software-in-the loop and hardware-in-the-loop test capabilities. First, the system architecture of the simulation platform is introduced. All components of the platform are defined. Those components build the basis for the entire simulation. Special emphasis is given to the interaction between the simulated vehicle and its traffic environment. Second, this paper provides a radar sensor model framework and a vision sensor model framework to establish virtual sensor models to enable high-fidelity simulation on environmental sensing and perception for virtual development, testing and validation of ACC system. Finally, this paper gives an example of ACC under traffic conditions to verify the simulation platform.

：In this paper,HCI solution in the chemical corrosion tests carried out in room temperature,measured mass loss of CFRP tendons. After extraction and analysis, preliminary search the FRP reinforcement corrosion mechanism under acid erosion. The tensile test is done at 60d and 120d,respectively. Determination of the tensile strength of CFRP tendons. The experimental analysis of the data collected, identify the law of CFRP reinforcement corrosion. Fiber reinforced composite material (Fiber Reinforced Polymer, of FRP ) is a continuous non-metallic fibers and fabric reinforced thermosetting or thermoplastic resin matrix composite made of a new material . Fibers and resin matrix composed of FRP bars under normal circumstances is not easy to rust, but in recent years, the study found that acid salt , moisture , UV , temperature and other environmental conditions on the long-term performance of FRP bars have a certain impact[3-5]. By CFRP tendons under acidic corrosion durability test study reveals CFRP tendons under the corrosive effect of the variation of the quality and strength . Can provide a theoretical basis for CFRP tendons durability design , to provide theoretical guidance to improve the efficiency of the FRP bars in harsh conditions .

SiCp/A356 composites containing 20% (volume fraction) SiC and three kinds of different filler metals were investigated by vacuum brazing process. Brazability of SiCp/A356 composites was analyzed after nickel plating on the surface of composites and without nickel plating process. The effects of holding time on microstructure of the brazed joints of SiCp/A356 composite were studied by metallographic microscope, SEM and Energy spectrum analysis. The results showed that nickel plating on the surface of composite contributed to improve brazability of SiCp/A356 composites prominently, while inferior brazability displayed without nickel plating on the surface of composites. Hardness of joints brazed at holding time of 6 min, 8 min and 10 min were studied, consequently the hardness of the weld seam region is the highest when the holding time was 8 min.

Technology of Micro-grid emerges, and power distribution system faults, allowing for the distributed generation keeping alive the islanded operation with the important load . But if the interior of Micro-grid happens a fault again, the short-circuit current of Micro-grid is so insufficient that traditional current protection can not play a part in the protection. In order to solve this problem, it introduced a new relay protection strategy, and provided the basis for the relay protection design of Micro-grid in the future.

According to the environmental conditions on the blasting spot,the blasting notch shape and the blasting parameters were reasonably chosen,and series safety measures were reasonably adopted,which made a sixty-five-meter brick chimney to be demolished successfully.

Root-tuber crops are buried under the ground, thus, the mechanization harvest should apply digging method. However, the row-aligning angle of the shovel can directly influence the digging effect. Therefore, a set of auto-aligning technological equipments were designed to solve this problem and achieve aligned digging. This paper mainly analyzes the design of above mentioned equipments as below: A right-left angular displacement sensor is added in the front part to achieve auto-induction and signal transformation of the digging angel through comparison of the pressure angle. The adjustment of the control equipment can be achieved by the adjustment of signal when it goes through magnetic exchange valve. And with the help of cross slide way, the digging harvest machine can modulate the shovel timely and efficiently. Experiments demonstrated that such auto-row-aligning equipment can improve the digging effect.

Keywords: Hot-Dip Aluminum; Corrosion resistance; Fe-Al Intermetallic alloys Abstract. The hot-dipping Al coating was developed on 22MnB5 steel surface. Effects of corrosion resistance with different dipping time coatings were investigated in this paper. It is describes an approach to improve the corrosion resistance of 22MnB5 steel. The results of the polarization curves show that the dipping 2min coatings have the highest corrosion potential (Ecorr) and the lowest corrosion current (icorr), indicating that this coating is a best corrosion inhibitor. It is similar results with EIS for corrosion resistance, respectively. The proper thickness (~20µm) of Fe-Al compounds between Fe substrate and Al coatings must be selected (750°C, hot-dipping 2min) in order to improve corrosion resistance for 22MnB5 steel.

The paper presents the design of a small-scale building integrated photovoltaic micro-grid system, which is a master-slave system with bi-directional battery inverter as the core of the system.A photovoltaic energy system and management system are established, which has the function of real-time data monitoring and logging，switches different micro-grid operation mode. On this basis, the photovoltaic cooling water system is presented to solve the decline in peak power generation of the system caused by the increase of the temperature of the photovoltaic panel. Experimental results show that the stability of the system can run in networked mode and island mode, cooling water system of photovoltaic panels improve the total system power generation.

In this paper, a kind of 304 austenitic stainless steel sheets has been investigated, and systemic tests were conducted to study the law and mechanics of work hardening of 304 austenitic stainless steel. The results of microstructure analyzing of 304 austenitic stainless steels showed that when it was deformed by means of tensile testing at room temperature, obvious work hardening was caused by the changes of structure during the deformation. The strain-induced α-martensite, ε-martensite and deformation twins enhanced flow stress obviously, which is the main reason for the strong work hardening in FCC metals and alloys with low stacking fault energy as 304 austenitic stainless steel.

To measure the concentration of CH4, we developed a thin film piezoelectric acoustic sensor (TFPAS), it accomplishes the detection of CH4 by the absorption of CH4 which can change the oscillation frequency of the piezoelectric crystal. The sensor is mainly composed by the piezoelectric film, sensitive film, silicon substrate and electrodes. The sensitive film is made up of nanometer-sized MgO scattered on pitch-based activated carbon fibers which has a strong adsorption of CH4. The piezoelectric film is a ZnO film which has very high piezoelectric characteristic parameters. The experimental results show that the sensitivity of the sensor to CH4 is very high. The response of the sensor to the presence of CH4 tested was found to be linear within a certain detection range and the detection error is less than 5%.

Polyphenylene sulfide-intercalated layered manganese oxide (PPS-MnO2) nanocomposite is synthesized via the delamination/reassembling process. SEM images and XRD analysis indicate that the surface of the nanocomposite material is layered and the basal spacing of PPS-MnO2 was 1.69 nm. The maximum specific capacitance as obtained from cyclic voltammetry was 524.0 F•g−1. The specific capacitance decreases by 6% of the initial value over 1000 cycles at a high current density of 2mA•cm-2.

The strength of gravel soil of Yili’s First Mine in different water contents was studied by multifunction static and dynamic triaxial test machine. The results show that （1）The yield limit decreases with the increasing of water content under steady confining pressure, and the greater the confining pressure, the greater the yield point of its axial in the same moisture conditions. （2）The expansion becomes into contraction with increasing moisture content. （3）Strength index of gravel soil becomes smaller with the increase of moisture content. The relationship between friction angle and water contents is . And the relationship between cohesion (or bite force) and water contents is . The results provide a theoretical basis for shaft design and construction of Yili’s First Mine.

On the preparation of porous ceramics with composite sintering auxiliaries Y2O3-Al2O3 , the main ingredient of SIC , and CMC as the porous agent . Having studied the C content of composite structure and mechanical properties , And analysised the composite fracture morphology with SEM . The results show that, when using different particle size of carbon powders mixed the porous silicon carbide ceramic sample size powdered carbon than a single sample of micro skeleton intact, the shapes of holes, and more rules are uniformly distributed, comprehensive mechanics performance is better.

SrAl2O4:Eu2+,Dy3+ long persistence phosphors are synthesized by combustion method. The effects of several processing conditions such as the mole ratio of urea and metal nitrates, initiating temperature, the amounts of fluxing agent(boric acid), and raw material ratio（Sr:Al）on phase composition and subsequent on the spectroscopic properties are studied. The results show that the phase composition changed from strontium-rich phase to aluminium-rich phase with the increasing of initiating temperature, the increasing of the content of urea and boric acid, and with the decreasing of Sr:Al. The results indicate that the sample has most excellent luminescence performance is not the one which has pure single phase SrAl2O4, but the one has little impurity phase SrAl4O7. Similar phenomenon is also present when synthesized by high temperature solid-state method and microwave plasma synthesis method, so the differences among three methods are also discussed in this paper.

Cobalt oxide-Polyaniline (Co3O4/PANI) nanocomposites were prepared via inverted emulsion polymerization. The structure of the obtained composites were characterized by X-ray diffraction (XRD). The electrochemical behavior was studied by cyclic voltammetry(CV) and electrochemical impedance spectrometry(EIS) experiments. The Co3O4/PANI(1:2) composite calcined at 400°C exhibits the highest capacitance value of 357 F/g at the scan rate of 5mV/s.

There exists a thick layer of gravel in Quaternary alluvium surface soil layer in most areas of Xinjiang, China. When passing through the gravel layer during mine construction, mine workings collapse and rib spalling often happen, which influences the mine working’s construction and bring hidden danger to safe construction. This article took the engineering geological characteristics of thick gravel layer in Ili mining area in Xinjiang as background, carried out the gravel layer roadway’s deformation and failure tests based on the principle of similar model test, and analyzed and summarized the law of the surrounding rock deformation and failure. The results indicates that: Seepage is the decisive factor in the destruction of gravel layer surrounding rock; roof displacement increased from 1.8mm up to 3.4mm when the gravel layer roadway surrounding rock’s water content grows from 7% to 12.67%, which shows that displacement of surrounding rock increased with the increase of water content; coupling support has the best effect in gravel layer roadway. The research results play a guidance role and have a reference value for the engineering with the same type of roadway design and construction.

The impeller is an important component applied in airplanes, ships and weapons. It is difficult to form the complicated geometry of the impeller by using the conventional forging and casting technology. Semi-solid forming is a promising forming process that can produce complicated and high-quality components of wrought aluminum alloys. In this paper, the formability of the impeller was investigated by using advanced semi-solid forming technology and self-designed combined die, as well as quick forging hydraulic press. Experimental results show that the formability of the impeller increases with the increase of reheating temperature and holding time of the billet. When heating temperature and holding time during the pretreatment of the billet were 620°C and 25 min respectively, reheating temperature and holding time of the billet before thixoforging were 600°C and 90 min respectively, preheating temperature of the die was 320°C , the impeller was formed perfectly on the quick forging hydraulic press.

The metal transfer process with different welding parameters in rotating arc narrow gap horizontal welding is successfully observed by the high-speed photography system. The effects of wire rotating frequency on metal transfer process in rotating arc narrow gap horizontal welding are novelly explored. The metal transfer with different wire rotating frequency presents different modes. The results indicate that the droplet transfer has stable process with the rotating frequency of 5-20 Hz. And the weld formation is quite shapely. But with the high rotating frequency of 50 Hz, the metal transfer process is not acceptable and the weld formation is very pool. Metal transfer process is one of the most important factors of effecting the weld formation in rotating arc horizontal welding process besides the molten pool behavior and welding thermal circles.

SrAl2O4:Eu2+, Dy3+ long persistence phosphors are synthesized by microwave plasma method. The effects of molar ratio of Dy3+ and Eu2+ on the phase composition, the spectrum properties and long afterglow property of phosphors are investigated in the paper. The analysis results show that spectrum properties depressed clearly following the increase of Dy3+/ Eu2+. And the afterglow property of phosphors are improved by doping of the Dy3+, but suppressed by excessive doping. On the one hand, this is because that the number of electrons trapped by defect levels increased with the increase of Dy3+. But on the other hand, it’s difficult to occur electric transition if doping excessive Dy3+, so leads to performance depressed. Above-mentioned results, it’s confirm that the optimized Dy3+/Eu2+ molar ratio is 2:1 when SrAl2O4:Eu2+, Dy3+ phosphors synthesized by microwave plasma method.

Single edge notched beam (SENB) and indentation methods (IM) were used to test the fracture toughness (KIC) of SiC ceramic in present work. Both of testing results were compared. The applicative computational equation of indentation crack was determined through studying indentation morphology formed by IM. The results showed that the indentation crack in SiC could be Babcock crack, and the KIC value calculated by Niihara (P) indentation equation approximated to real value mostly with minimum relative deviation.

In order to study high strength and other characteristics of high strength concrete, scanning electron microscopy and mercury pressure method were used to analysis the surface morphology, organization, structure, composition and fractal features of C100 high strength concrete materials in terms of the microscopic mechanism, and the material strengthen mechanism and the causes of failure were revealed. The results shows that, as the adequate hydration and particle hydrates increase in C100 concrete, more gel-like mesh or wrinkles are generated, and there is a strong bonding effect between fine particles. As the use of mixing composites material in C100 high strength concrete, the density of the material is improved and the proportion of harmful hole is lowed, and its mechanical properties and durability are all improved. When concrete is damaged, cracks increase and coalescence show an increase of fractal value.

Fault diagnosis is a kind of pattern recognition problem and how to extract diagnosis features and improve recognition performance is a difficult problem. Local Linear Embedding (LLE) is an unsupervised non-linear technique that extracts useful features from the high-dimensional data sets with preserved local topology. But the original LLE method is not taking the known class label information of input data into account. A new characteristics similarity-based supervised locally linear embedding (CSSLLE) method for fault diagnosis is proposed in this paper. The CSSLLE method attempts to extract the intrinsic manifold features from high-dimensional fault data by computing Euclidean distance based on characteristics similarity and translate complex mode space into a low-dimensional feature space in which fault classification and diagnosis are carried out easily. The experiments on benchmark data and real fault dataset demonstrate that the proposed approach obtains better performance compared to SLLE, and it is an accurate technique for fault diagnosis.

ZrB2 powder has been prepared through carbothermal reduction boronization of zirconia/boron carbide/carbon mixtures heating assisted by microwave. The powder characteristics were investigated by X-ray diffraction (XRD), X-ray fluorescence (XRF), nitrogen absorption (BET model) and scanning electron microscope (SEM). The experiments indicated that excessive B4C is necessary and the carbothermic reaction reacts severely at a higher temperature and complete at 1600oC. The crystallite size has ranged from 50-100 nm, according to the calculated surface area. Highest purity of ZrB2 powder, which was synthesized at 1600oC, is 99.67 wt%. The surface area of ZrB2 powder synthesis at 1600oC is 18.33 m2/g. Vibration of temperature should affect the purity of ZrB2, as the sub reaction acted.

Incremental sheet forming (ISF) is an innovative and highly flexible sheet metal forming process for small batch production and prototyping, but springback is a very important factor to influence the quality of incremental sheet forming. This paper investigates the springback mechanism of incremental sheet forming using numerical method. A three-dimensional elasto-plastic finite element model was established for the simulation of the incremental sheet forming process. In this model, the combination of dynamic explicit algorithm and the static implicit algorithm was proposed to calculate the whole forming process including springback. The results of numerical simulation, such as, the strain history and distribution, the stress state and distribution, etc., are discussed in details. Moreover, the results confirm that residual stress has been releasing during forming process, which reveal the peculiar springback characteristic of incremental sheet forming process.

In order to alleviate the suffering of the patients with skull defects, this paper presents a detailed analysis of incremental sheet forming (ISF) method to shape skull prosthesis of titanium alloy meshed plate. In the study, we emphasized the following points: First, we designed and made skull model based on computed tomography image, and extracted the skull defect data using reverse engineering technology, then we reconstructed the surface of the prosthesis and designed it’s three dimentional model, finally, we adjusted tool path repeatedly and then imported the tool path into incremental sheet forming system to shape skull prosthesis. This paper provides a fast and accurate prosthesis manufacture method of titanium alloy meshed plate, which can improve the level of the skull repair technique.