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Nowadays intelligent vehicles play a more and more important role in daily life. In this paper, a track-hunting intelligent car is presented for intelligent control research. In the direction control of this car, a fuzzy Proportional-Integral-Derivative (PID) controller is applied to make a distinction between different situations and execute self-tuning operation at the same time. The controller is tested by simulation and experiments in this paper, and results prove effectiveness of the controller.

Bipolar plate is the key component of proton exchange membrane (PEM) fuel cell and represents a significant part of the overall cost and the total weight in a fuel cell stack. Many research have been done on the manufacturing methods of bipolar plate, among which stamping is very popular. With the increasing of the channel number and complexity, its dimensional error caused by sprinkback will change a lot, even under the same forming process. And the risk of crack is also different. These all impact the quality of bipolar plate. In order to predict deformation of channels and the plate’s quality, the displacement along X-axis, the strain and stress state, and the displacement along Z-axis are measured. The results show that 1) the risk of crack increases with the increasing of channel number; 2) the springbacks increase with the increasing of channel number; 3) the most dangerous point locates on the right internal fillet of the plate’s last section.

Axial deformation of the ring during the traditional vertical hot ring rolling (VHRR) process has a considerable effect on the ring products’ quality. In this paper, the ring’s axial deformation of VHRR process of three different rolling modes, that is, open-die mode, close-die mode and open-die mode with conical rolls like the radial-axial ring rolling (RARR) process is analyzed. Three groups of 3D coupled thermo-mechanical FE models of VHRR process are established in software ABAQUS, and the axial deformation and the width spread of the rings are studied in detail. Finally, a special conical roll device was designed and equipped on the traditional VHRR mill, and series of VHRR experiments are conducted, the results of both simulation and VHRR process show that the formed rings utilizing open-die rolling with a special pair of conical rolls has lower axial deformation, smoother end surface and higher precision than the formed rings utilizing open-die rolling and close-die rolling. The research results can supply an effective approach to axial deformation control of traditional VHRR process.

A method is presented for gear modeling and simulation based on a hybrid of back propagation (BP) neural network and genetic algorithm (GA). Generally, the method of mechanical design includes building up 3D models and gets them checked in corresponding software, which is complicated and takes much time. This proposed method offers a quick way for designers, which combines finite element analysis (FEA) with a hybrid of BP neural network and an intelligence global optimization algorithm, i.e. genetic algorithm (GA). ANSYS APDL is applied to build up the FEA database, which offers data for study and training of BP neural network. Then, the GA is applied to optimize the process parameters that would result in optimal solution of the BP neural network goals. The case study demonstrates that the proposed method can get accurate results in a short time.

In this paper, a fault location method using power quality monitoring data is proposed. The fault location is divided into two classes including fault line recognition and fault distance calculation. Along the each power line in the target network some fictitious fault points are set and the fault voltage of each monitoring bus is calculated. The voltage dip calculation results and the fault line data are matched to form the learning samples and then train the designed fault line recognition BP artificial neural network. The trained neural network searches the fault line when actual fault occurs. After it finishes fault line searching the fault position is calculated using the function of voltage dip amplitude and fault position. The correctness and effectiveness of the proposed method is proved by the simulation results in standard IEEE-14 bus system.

To ensure the normal drilling and well site safety, a monitoring system is necessary in air drilling to monitor the real-time information in total drilling. By using the LMS algorithm and adaptive delayed transversal filter, a mathematical model of underground blasting monitoring is established, and an information monitoring system is also developed based on wireless communication and field bus technologies. The system is characterized by miniaturization, lower cost, convenient operation and transportation, powerful function. The experiment results show that this system can not only provide accurate air drilling parameters and stratum information, but also can monitor the real-time contents of flammable, explosive and toxic gas, which provides a guide for the identify of water-oil-gas layer, supervising drilling and preventing the occurrence of safety accidents in well site.

During the long engineering project construction period, involving a combination of human, financial and material, and that different works, every link and each phase is mostly high altitude, open, crossover operation, which hide safety risks and result in high probability of safety accidents, so these characteristics determine the importance of safe and civilized production. Therefore, the influence factors of engineering construction safety are worth studying. In this paper, through extensive reading literature and information, making contrast and analyzing, researching and other methods, finishing the preliminary indicators of construction safety influencing factors, after conducting questionnaire survey, ultimately identified 19 indicators of factors and based on these indicators draw SEM model by AMOS software. The results by AMOS show that the model can effectively describe the relationship between the influence factors of which affecting construction safety, and provide strong evidence for improving the engineering and construction management.

Information fusion is the main method to improve diagnosis accuracy. In this paper, fusion information entropy is defined by fusing speed with three kinds of information entropy that are singular spectrum entropy in time domain, power spectrum entropy in frequency domain and wavelet energy spectrum entropy in time-frequency domain from multiple perspectives to describes vibration fault characteristics. According to the principle of entropy increase, condition information entropy increase of vibration fault are defined and used as new criterion for fault diagnosis, and the grey correlation between sample fault and typical fault is defined to realize the vibration fault diagnosis. Finally, the method’s effectiveness is verified by vibration simulation data from vibration fault simulator. The result shows that this method can identify 6 typical vibration faults correctly.

With the power increase of the wind turbine, the scale of the blade is increasing, further improving the performance of the blade, improving the stiffness and stability of the blade, inhibiting the vibration and noise of the blade and reducing the blade weight has become an problem urgently needed to be solved with for the design of the large wind turbine blade. The unique external shape of organisms, the perfect unity of the function, structure and material, the excellent capability for adapting the environment, also provides an inexhaustible inspiration for the bionic design of wind turbine. Applying the biological non-smooth and self-cleaning effect and imitating the biological medial axis pattern structure, self-adaptive characteristics conduct the bionic design of the wind turbine blade, it can effectively realize drag-reduction and lift enhancement for the blades, noise reduction, lightweight, and can improve the self-adaptive ability, resisting wind and sand, preventing icing up. Paying attention to research on biological mechanism, perfecting the bionic design theory, implementing the multidisciplinary design optimization, strengthening the research on model, have an important significance on improving the bionic design effect for the wind turbine blade and promoting the bionic engineering application.

Thermal energy storage is the main way to ensure solar power plant to generate electric in the form of stable and continuous. In this paper, a structure optimization model for large-scale, commercialization solar thermal energy storage system is proposed according to life cycle analysis. Based on the analysis of thermal energy storage medium, thermal energy storage tanks, insulation, bottom bearing structure, pump energy and land use, the optimization of thermal energy storage system is realized. Finally, the structure optimization design for 50MW solar power plant is implemented and storage tank’s geometric parameters are calculated. This research can provide technological support for large-scale application of solar thermal generation.

Through manufacturing the model and using the static experiments, examining the effectiveness of the bionic structure design and the reliability of infinite element analysis has become an important procedure on the bionic structure research. With its fast, flexible benefits, RP becomes an effective tool for the evaluation of product model design, rapid manufacture and the performance tests. According to the characteristic of the plant vein staggering and tilt, small airfoil obtained through the optimal combination of the characteristic belongs to the typical thin shell parts. Internal beam interconnects with the rib, the pore with different size and shape distributes on the wing rib, which needs a good surface quality and a certain accuracy and strength, thus it is difficult to make. SLS is suitable for the complex thin-walled parts without support, low processing costs, Through the rational selection of layered and forming parameters, it obtains the SLS small wing archetypes and bionic-type sample, which has a good apparent quality after disposal and is suitable for model statics test etc.

The steering engine is a import execute component in controlling of humanoid robot、manipulator and model aircraft . In this paper, with the single chip processor STC89C52 as the core, and adopting the timer interrupt through serial communication way of real-time control system to produce PWM waves. This method has low cost and simple hardware design, can achieve more independent PWM waveforms output.

Experiment research for aseismic performance of RC Column strengthened by self-compacting concrete under second force is completed. By comparing three comparison columns and three columns strengthened by self-compacting concrete in low-cycle reciprocating horizontal loads seismic performance test, the specimen described the typical features of breakage, and the hysteresis and ductility of the RC column reinforced or not by self-compacting concrete is analyzed, the reinforcement effect by the different initial force is compared. The results show that: reinforcement by increasing the cross-section of self-compacting concrete is an effective method to significantly improve the shear strength of reinforced concrete columns and specimen ductility. The presence of the initial force have impact on reinforcing effect of RC columns, the greater the initial force, the more obvious impact.

This paper produced four frame joints strengthened by self-compacting concrete and one unstrengthened joint for comparison. Take MTS servo loading system of static test for the frame joints under secondary load，to study the influence of different interface treatments for the seimic performance. The interface of the four strengthened joints respectively using roughening and grooving with different grooving density. The results of the damage process, strain of the old steel and new steel, the load -displacement hysteresis loops was analyzed，and it was found that the cooperational performance of the old concrete and new concrete was good when using self-compacting concrete to strengthen the frame joints with the interface treatments roughening and grooving. Considering the impact of the interface treatment, the ultimate strength, displacement, and displacement ductility coefficient of the reinforced joints etc. were slightly increased. And the the more the grooving density was, the better the strengthening effect was, which could be considered in the design of strengthening as its interface treatment.

Influence of compounded mineral admixtures on shrinkage and early-age cracking behaviors of concrete was studied, based on the fellow factors: fly ash to blast furnace slag(denoted as BSF) ratio, fly ash-metakaolin ratio, BSF-silica fume ratio. Research shows that the Pozzolanic admixtures compounded with cementitious admixtures have complementary and synergistic effect for hydration progress of concrete, which can enhance the volume stability and cracking behaviors of concrete. However, the pozzolanic admixture compounded with other pozzolanic admixture, two pozzolanic admixtures will grab Ca(OH)2 resource. And then if the dosage of mineral admixture is higher, the compounding will result to decrease the volume stability and cracking behaviors of concrete.

The shrinkage cavity defect of the extruded boss is harmful to the quality of fine blanking workpiece and process. To suppress the shrinkage cavity defect, firstly, the boss extrusion is simulated to analyze main features of metal flow and the causes of the shrinkage cavity defects; secondly, some parameters affecting the material flow, such as the size of die and punch, blank holder force, friction coefficient, sheet thickness and counter force, are studied to figure out their influences on the depth of shrinkage cavities respectively; finally, the process parameters of a special workpiece are selected according to research results above, and experiment verified that the selected parameters can suppress the shrinkage cavity defect pertinently. In the paper, the shrinkage cavity defect is systematically studied for the first time, and this provides the base to design and optimize the extruded boss feature in fine blanking process.

Long time corrosion is carried out on a kind of new Ni-based super alloy used as a component of gas turbine engine, under salt-fog atmosphere at 700°C850°C for 200h. The salt solution component is 75% sodium sulfate plus 25% sodium chloride. The surface of the alloy was coated with salt solution at 150°C and aged at 700°C,750°C,800°C and 850°C for 10h, 50h, 100h and 200h, respectively. It is found that with the increase of temperature and aging time, the weight and thickness of the corrosion layer increase, and the corrosion becomes severer on the alloy surfaces. In the beginning of high-temperature corrosion, the corrosion speed increases quickly, and as prolong of corrosion aging time, corrosion speed turns to be invariable, and it is correlated to the formation of an oxidized layer by which the increasing of corrosion speed is restricted.

In order to enhance the efficiency and the level of instruments management in colleges and universities, the management system of instruments sharing based on RFID technology has been designed, developed and brought into operation. Automation and intelligentization of lots of work have been achieved such as user authentication of instruments, open reservation of instruments, charge and sharing of instruments, real-time management of laboratory, settlement of expenditure and benefit evaluation, promoting the open sharing of instruments in colleges and universities.

The hydration degree of binders and cement is investigated by measuring the adiabatic- temperature rise of concrete at low water-binder ratio with different fly-ash content. The results denote that, with a constant water-binder ratio, both of the hydration degree of binders and that of cement decrease with the increasing fly-ash content in the early stage. In a later stage, however, the hydration degree of cement increases with the increasing fly-ash content and the hydration degree of binders peaks when the fly-ash content is 35%. Fly ash is one of the mineral admixture of which high-performance concrete is made up. It brings down the rise of concrete temperature significantly and helps solve the problems of shrinkage and crack of concrete structure. Because the hydration mechanism in common concrete is different from that in concrete with low water-binder ratio, and the hydration environment is different between concrete and cement pastes, to determine the adiabatic-temperature rise of concrete directly conforms to the actual situation. The adiabatic-temperature rise, adiabatic-temperature-rise rate, hydration degree of both binders and cement are investigated by measuring adiabatic-temperature rise of concrete with different fly-ash content.

As a key component of proton exchange membrane fuel cell (PEMFC), the bipolar plate’s performance will directly affect the power output and battery life of the fuel cell. The conventional metallic bipolar plate is prone to warp, and has large flatness error with residual stress induced by forming process. This will result in contacting incompletely with membrane electrode assemblies (MEA) and lower fuel cell efficiency. A cylindrical structure of the PEMFC metallic polar plate is proposed to improve its stiffness and to reduce assembling error of the fuel cell. The polar plate features, which were originally designed on a flat surface, are projected onto the cylindrical surface with a certain curvature. Two cylindrical polar plates are welded together to become a bipolar plate. The finite element method is applied to compare the stiffness of the conventional and cylindrical polar & bipolar plates. The cylindrical bipolar plate has better stiffness and anti-warping than the conventional bipolar plate. The feasibility of the cylindrical structure is verified by experiment and provides a new idea for the improvement of the bipolar plate and fuel cell stack.

It is of great necessity to carry out safety assessment of high risk operations in hydroelectric projects. We analyze the key problems of safety assessment of high risk operations. Specifically, a questionnaire can be designed by applying the method of Failure Mode and Effects Analysis (FMEA) firstly; then the factors and consequences of risks in such operations can be generated by the questionnaire and interviews; further, the relationship among those factors can be determined based on statistical analysis, and a comparison matrix of Analytic Network Process can be constructed accordingly to verify and modify the model for safety assessment; finally, based on the outcome of safety assessment, the weak point in the hydroelectric project can be revealed and monitor, so that the safety of the project can be improved.

To remove casting porosity and obtain smaller crystal grains, many large forgings need ingots to be upset axially with large ratio of height to diameter (H/D) greater than 3. But the ingots with large H/D are prone to buckling during upsetting process, and have non-uniform internal stress and strain distribution, cracks at barreling and other defects. A new axial upsetting process was proposed to handle these problems. Firstly, the research described deformation inhomogeneity and cracking tendency, and analyzed the causes of defects in the flat anvil upsetting process. Secondly, three two-stage upsetting processes were tried to improve the uneven deformation in the flat anvil upsetting, which applied symmetrical spherical convex die, conical convex die and multi-line sweeping concave die respectively in the first stage, and used flat anvils in the second stage. The effect of the die surfaces on constraining those defects was analyzed. Finally, three three-stage upsetting processes were suggested to take advantages of different die surfaces to stabilize the process. It was observed that the upsetting had better result from using conical convex die and multi-line sweeping concave die in the first stage, conical convex die and flat anvil in the second stage, two flat anvils in the third stage. The new axial upsetting process could improve the quality of the large forgings with more uniform deformation and less barreling.

Co-based WC powder and self-fluxing alloy powder Ni60A were sprayed on hot work die steel H13 substrate via high velocity oxygen fuel (HVOF) spray processing, and microstructure and mechanical properties of two types of coatings were investigated. For WC-12Co coating, some pores were observed, while microcracks were only observed in Ni60A coating, which leads to the lower microhardness and abrasion-resistance at either room temperature or high temperature. At the junction of H13 substrate and WC-12Co coating, metallurgical combination was observed. Under the test condition of load 250g and rotating speed 448r/min, the average friction coefficients obtained at 10 are 0.33 and 0.35 respectively; when the test temperature was 500 , the value of two types of coatings increase to 0.56 and 0.63 respectively. Compared with Ni60A coating, The WC-12Co coating had an excellent abrasion-resistance at high temperature; the weight loss was only one-fifth of the Ni60A coating.

Bipolar plate is the key component of proton exchange membrane (PEM) fuel cell and represents a significant part of the overall cost and the total weight in a fuel cell stack. The thin sheet metal, with usually 0.1~0.3mm thickness, deformed to bipolar plate with flow channel 0.5~2mm width and depth, by rubber pad stamping can reduce the cost greatly. The rubber pad is simulated by solid element and hydraulic pressure respectively. Experiment shows that the hydraulic pressure can simulate the rubber pad. The thin sheet metal is modeled by solid element and shell element respectively. Considering thin sheet metal material size effect, the shell element cannot simulate the thin sheet metal stamping process because of small corner radius. Modeling rubber pad by hydraulic pressure and thin sheet metal by solid element, the simulation of the rubber pad stamping process shows that 1) the sheet metal in channel appears large uneven strain with high stress; 2) convex fillet make the sheet metal two direction tensions and should keep large fillet corner. Those simulations are validated by experiments. The research on rubber pad stamping will improve the understanding of this micro forming process and provide design guide of flow channel.

Collaborative filtering (CF) technique is the most successful method for recommendation system. In this article, we developed a fashion recommendation system by using CF technique. In order to improve on data sparseness problems in CF technique, firstly we built users’ similarities based on users’ background information which is related with fashion, then the neighbors’ predicting ratings were filled into the U-I rating matrix in advance before the traditional collaborative filtering. While computing the background information similarities, we develop a hybrid similarity model which can deal with different types of properties. The method can solve the data sparseness of U-I rating matrix effectively.

The Conical Ring with Inner Steps (CRIS) is a typical profile ring, which is hard to be formed by ring rolling. Less-profile-filling and shrinking-drawing are the two main defects formed in the rolling process. Through the study of the rolling formability of CRIS with different ratio of height to diameter with the combination of FEM simulation method and experimental method, the main factors that affect the CRIS rolling formability are determined. The CRIS forging is designed. And the FEM simulation and experimental results show that the design method is reasonable.