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A coordinated Volt / Var control strategy for wind farm group is proposed. The area voltage control center monitors the pilot bus in the central substation where many wind farms are connected to, and coordinates all kinds of reactive power resources in different wind farms to regulate the voltage profile of all wind farms. The genetic algorithm is used to solve such a multi-objective optimization model. The simulation results of a typical wind power system show that the coordinated control strategy has better performance than the current individual one in respects of security and economy of the grid.

The three-dimensional coupled explicit Reynolds Averaged Navier–Stokes (RANS) equations and the two equation shear-stress transport k-w (SST k-w) model has been employed to numerically simulate the cold flow field in a special-shaped cavity-based supersonic combustor. In a cross-section shaped rectangular, hypersonic inlet with airflow at Mach 2.0 chamber, shock structures and flow characteristics of a herringbone-shaped boss and a herringbone-shaped cavity models were discussed, respectively. The results indicate: Firstly, according to the similarities of bevel-cutting shock characteristics between the boss case and the cavity case, the boss structure can serve as an ideal alternative model for shear-layer. Secondly, the eddies within cavity are composed of herringbone-spanwise vortexes, columnar vortices in the front and main-spanwise vortexes in the rear, featuring tilting, twisting and stretching. Thirdly, the simulated bottom-flow of cavity is in good agreement with experimental result, while the reverse flow-entrainment resulting from herringbone geometry and pressure gradient. However, the herringbone-shaped cavity has a better performance in fuel-mixing.

Objective: To study the influence of disc cutter spacing on rock fragmentation efficiency and optimize cutter layout and improve the efficiency of disc cutter. Method: ANSYS, a finite element software was used to simulate double disc cutter cutting process. Result: Find a good corresponding relationship between penetration and cutter spacing. At the process of sandstone, if disc cutter spacing as 54 ~ 55 mm, rock crushing as the largest and rock fragmentation efficiency is the highest; with the penetration of 10 mm. If disc cutter spacing as 66~68.5mm, rock crushing as the largest and rock fragmentation efficiency is the highest with the penetration of 15 mm. Changing the cutter spacing and penetration, rock stress and broken degree will also change. Conclusion: Double disc cutters change within the range of best cutter spacing, cutter spacing is proportional to the rock crushing. If the cutter distance is greater than the best cutter spacing, the ledge will be appeared. For one type of rocks, the penetration would have some effects on the optimal cutter spacing. If the penetration increases, the optimal cutter spacing increases gradually, at the time of other construction parameters unchanged.

The experiment on foundation improvement by dynamic compaction in Collapsible Loess foundation of the power plant was made. Before and after the experiment, kinds of in-situ and laboratory tests were performed .Through these tests, the influence of the dynamic compaction on the character of the soil, such as dry density, collapsibility, bearing capacity is analyzed. The effective depth of improvement of foundation is calculated and the conclusion of the efficiency of the foundation treatment by dynamic compaction is made. The choosing of techniques and parameter of the dynamic compaction also is elaborated in the paper, which make an example for other similar construction in the future.

Weighting exponent m is an important parameter in fuzzy c-means(FCM) algorithm. In this paper, an approach based on genetic algorithm is proposed to improve the FCM clustering algorithm through the optimal choice of the parameter m. Experimental results show that the better clustering results are obtained through the new algorithm.

Taking solar photovoltaic panels as the research object, infrared diagnosis technology is used to inspect the quality of crystalline silicon solar panels, and using infrared detecting principle of infrared thermal imager to design a set of device, which can detect the internal and surface defects of the solar panels. Common defects such as black piece, broken gate, crack and fragment can be detected and classified according to the infrared image characteristics of the four kinds of defects, also it can quickly locate the defects. Experiments show that, after image processing of the images captured by the infrared imager, it can be easily and visually to determine whether a photovoltaic panels is flawed. Last but not least, to classify the defects.

Aiming at the problems of extremely sparse of user-item rating data and poor recommendation quality, we put forward a collaborative filtering recommendation algorithm based on cloud model, item attribute and user data which combined with the existing literatures. A rating prediction algorithm based on cloud model and item attribute is proposed, based on idea that the similar users rating for the same item are similar and the same user ratings for the similar items are similar and stable. Through compare and analysis this paper’s and other studies experimental results, we get the conclusion that the rating prediction accuracy is improved.

This paper discusses the assessment problem on air quality. It will firstly make analysis on part irrationality of existing AQI and then introduces into concept of fuzzy mathematics on this basis. It makes index assessment on regional air quality according to 6 index values of selected air quality. Firstly, it will use fuzzy mathematics as basis to establish model of fuzzy comprehensive index and adopt weighting method of excess multiple considering each index to determine the weight, secondly it uses membership function of half-step trapezoidal method to determine its membership grade and makes compound operation to obtain fuzzy comprehensive assessment matrix, finally it makes fuzzy vector uniformization to get the new air quality index as well as uses national standard as reference limits to divide it into 6 grades and comprehensively makes index assessment on air quality.

Railway station is a comprehensive transportation hub. Its design and construction is far more complex than common public buildings, so as the construction management. This paper mainly explores the schedule risk management of railway station, including risk factors, risk indentation, risk evaluation and risk management. As many similar projects are under construction, Delphi technique method is most favorable for risk indentation. For risk evaluation, risk matrix method and CIM model are recommended to quantify the schedule risk. In the final part, the paper talks about the management of schedule risk. As schedule risk is abstract and its damage relatively slight, the risk prevention and mitigation are most suitable means.

A feedforward and feedback path tracking algorithm appropriate for automatic parking is proposed in this paper. This algorithm is composed of feedforward control and feedback control. In the path tracking, vehicle position and reference path information are used to calculate the lateral and heading error of the vehicle as well as the curvature of reference path, and put these three as the system inputs, the steering angel of the vehicle as the output. The system parameters are settled by multiple tests. Experiments show that, this method has a high performance in path tracking and meets the requirements of vehicle parking in both low speed situation and narrow spaces.

In engineering practices, aircraft structures have been damaged due to the structural corrosion, the corrosive problem of aircrafts needs to call high attentions for researchers because aircraft structures are composed of metals and compound metals. In this paper, corrosion problems and structural reliability of aircraft structures are discussed. Corrosion morphology and mechanism of aircraft structures are analyzed based on metal corrosion theory. The characteristics of the various types of corrosions of aircraft structures have been enumerated. The effect of environments in corrosion process of aircraft structures is studied. The law of corrosion developed at aircraft structural parts or materials is summarized. This research contributes to improving professionals capacity of corrosion prevention and control. It also provides technical support for aircraft maintainers.

In the past, the semi-active control study generally is calculated based on the MATLAB numerical procedure, which cant achieve fine simulation. In this paper, to solve this problem, the finite element software ABAQUS is taken to be secondary development, a numerical simulation method of studying semi-active control is proposed. And the seismic response of a steel column is taken for the research. the numerical simulation analysis of the semi-active control is carried out. The results show that the control effect of the control method is significant, and the simulation result is clearly visible.

An improved pure pursuit path tracking algorithm is presented for a four-wheel steering (4WS) carrier vehicle to follow a desired path automatically. A bicycle vehicle model considering the 4WS carrier vehicles structural and steering features is applied in the method. Real vehicle tests in an open large outdoor warehouse showed that the lateral tracking error was less than 0.56m at 20km/h. And we can conclude that the enhanced method for 4WS vehicle has good tracking ability on flat road.

In traditional way, the segmentation of image is conducted by simple technology of image processing, which cannot be operated automatically. In this paper, we present a kind of classification method to find the boundary area to segment character image. Referring to sample points and sample areas, the essential segmentation information is extracted. By merging different formats of image transformation, including rotation, erosion and dilation, more features are used to train and test the segmentation model. Parameter tuning is also proposed to optimize the model for promotion. By the means of cross validation, the basic training model and parameter tuning are integrated in iteration way. The comparison results show that the best precision and recall can up to 97.84% in precision and 94.09% in recall.

Digitization is the inevitable trend of the social development. In order to meet the requirements of the social development, the garment industry should also speed up the digitization and informationization, to improve the technological contents of the garment industry. With the emergence and popularization of the emerging computer technology such as the visualization, virtual reality and so on, the clothing design has received a profound influence in the design concept, design style and means of communication. This paper focuses on the analysis of the development of virtual reality technology in the field of fashion design, and summarizes the future prospects.

A novel and efficient method for the synthesis of 4-hydroxy-6-substituted-pyrazolo [3,4-d] primidines with acetic acid via phenol esters intermediate has been developed. Compared to the results obtained from the base substituted conditions, acetic acid catalyzed synthesis afforded target products in good yields.

Based on Roller Straightening Theory and Elastic-Plastic Beam Research, A Appropriate Mathematical Model of Straightening has Set up.The Author Regards the Tube as a Continuous Bending Beam and Discuss in Detail the Relationship between the Straightening Force and the Bending Moment. Calculating the Amount of Deflection for Tube. in this way ,it Provided a Scientific Basis for the Copper-Clad Steel Tube Straightening Parameter Set and Engineering Application.

Kinematics simulation study on Morse CVT input mechanism was established by using simulation software Adams, and it can get curves of displacement, velocity and acceleration of input mechanism of each bar to research its movement characteristics. This method is suit for kinematics simulation of connecting rod mechanism, meanwhile it can modify corresponding simulation parameter and is easy to do optimal design.

A small level measurement system is designed by installing a compact capacitive level sensor in the small container. By analyzing the capacitive sensor structure, a sensor measurement circuit is designed with high sensitivity, measuring stability and good repeatability. Capacitance measurement circuit makes use of multiple harmonic oscillation principle. The microcomputer measures the oscillation frequency of the multivibrator, and calculates the liquid level height based on the monotonic function about the liquid level height and frequency.

Experiments were separately carried out on Liquefied Petroleum Gas (LPG) and gasoline as fuel for a spark ignition (SI) engine. According to the indicator diagram and the calculation of corresponding heat release, combustion characteristics of the two fuels were analyzed. The results showed that using LPG would lead to 7.64% power reduction and a little peak pressure reduction when the structures and ignition advance angle of the engine were remained. At rated speed and full load, the power of engine fueled with gasoline reaches the maximum when the excess air ratio is 0.90 and 0.76 fueled with LPG; when comparing the maximum power and specific heat consumption at different excess air ratios, we can see that the change of excess air ratio has a greater effect on the engine fueled with gasoline than that fueled with LPG; the specific heat consumption of both fuels decrease with the increase of load. Besides, under the same Фa, LPG has a shorter combustion delay period, faster combustion speed and shorter combustion period than gasoline.

The structural characteristics of a wharf segment may be modeled by using the simplified model due to unacceptable matrix sizes. The concept of simplified model is introduced at first. The locations of simplified model that represent original structure are determined by the locations of pile groups in defined areas. Force-displacement curve is calculated for wharf structure by pushover analysis, and simplified model is constituted applying estimated secant stiffness and effective damping according to force-displacement curve. Peak value of seismic response is estimated using elastic modal response spectra analysis and compared with simulated results from nonlinear time history analysis. It is proved that peak value of seismic response can be calculated using simplified model rapidly, and close to time history analysis result.

With advances in technology and machinery manufacturing technology, the satellite navigation system plays a more and more important role in the modern society. People demand increasingly for satellite navigation. Satellite navigation is increasingly used in military systems, so military and civilian value is higher and higher. For the satellite signal reception, microstrip antenna plays an indispensable role. As the mechanical design of microstrip antenna is simple, easy manufacture, low cost, smaller size, lighter weight, with the overall unity of active devices and integrated circuit, etc. The successful development of high dielectric constant ceramic material enables the area of microstrip antenna to narrow several times. Microwave dielectric ceramics material has some merits such as high dielectric constant, thermal stability and excellent characteristics of small dielectric loss. Different dielectric constant substrate can be prepared through changing and doping modification of process parameters, including the relative dielectric constant of microwave dielectric ceramics for more than a few dozens which can be used for different microwave frequencies. Those are important reasons for promoting the development of microstrip antenna.

Tunnel Boring Machine (TBM) is a major equipment used in underground engineering and Cutter disk system is its major parts, which affect sharply its capability. The force and vibration characteristics of the cutter system are simulated in this paper, and the effects of its force and vibration on the cutter system reliability are analyzed. These results show that there are the most stress and the worst reliability in these joints between the cutterhead and main driver, the cutterhead and the hob, and cutter ring. These research results are very helpful for increasing the reliability and application of the rock boring machine.

In order to burning LPG and gasoline and dual fueled (LPG and gasoline) in the same engine, a new multi-function engine was refitted and designed based on 188F gasoline, mutative effects on the power and emission performance when burning those three kind fuel were investigated by the engine operated with the US EPA Phase-Ⅱ. Three schemes for the carburetor throat were designed. Balanced of the power and economy performance, when the diameter of the carburetor throat is 23mm, the performance was the best. By carrying engine performance test and the combustion process analysis, the results showed that: when the throttle was full opened, the power of burning only gasoline was 7.97kW, 0.5 kW and 0.28kW higher than burning LPG and dual –fuel. Burning gasoline pressure curve with the crank Angle siege area is the largest. As the emission test shows, when separately burning LPG and gasoline and dual fueled, the tendency of the excess air coefficient and the emission characteristics with the load change are same. When using LPG and dual-fuel, compared with burning gasoline, HC and NOx emission were reduced.

In order to determine the disc cutter’s kinematic behavior, a 3-D FEM model is established to simulate the rock cutting process in Abaqus, using a unique connector element and considering the failure effect of the rock. Then, by using this model, a series of numerical simulations during disc cutter’s wearing process have been performed. The results show that the speed zero point is jumping near the deepest rock breaking point, the rotating speed of the disc cutter varies while it is cutting rock and the average rotating speed increases during its wear process. In the end, the laboratory test is presented in detail, and the experiment results are in accordance with the simulation results.

Drought is a world-spread problem seriously influencing grain production and quality, the loss of which is the total for other natural disasters, with increasing global climate change making the situation more serious. Rice is the staple food for more than 23% of world population, so rice anti-drought physiology study is of importance to rice production and biological breeding for the sake of coping with abiotic and biotic conditions. Much research is involved in this hot topic, but the pace of progress is not so large because of drought resistance being a multiple-gene-control quantitative character. On the other hand, stress adaptive mechanisms are quite different, with stress degree, time course, materials, soil quality status and experimental plots, thus increasing the complexity of the issue in question. Additionally, a little study is related to weedy rice.In order to investigate the effects of drought stress on germination and early seedling growth of weedy rice (Oryza sativa f. spontanea L.) and cultivated rice (Oryza sativa L.), polyethyleneglycol-6000 (PEG-6000) are used to generate -1.33MPa and 0MPa water stress in a laboratory condition (28±3°C). Complete randomized design with three replications is used in the study. After 10 days of germination, shoot length, the longest root length, root fresh weight, root dry weight, shoot fresh weight, shoot dry weight and root numbers are measured; germination percentage, and root to shoot ratio are calculated. Germination index (GI), shoot length stress index (SLSI), root length stress index (RLSI) and dry matter stress index (DMSI) are used to evaluate the response of different genotypes to PEG-induced water stress. Results of ANOVA analysis show that responses of weedy rice accessions and cultivated rice varieties to water stress are significant different, demonstrating the germplasm of weedy rice and cultivated rice are diverse which enables us to screen the germplasm tolerant to drought stress.

Capturing an iris image rapidly is required for iris image acquisition embedded system. For the traditional method, an iris image must firstly pass through the quality evaluation, which is complex, so the acquisition speed is very slow. This paper described an iris acquisition embedded system, and a new capturing method. The system includes an DSP DM642, and some relevant peripherals. When an image is acquired, it is filtered by the capture-control function, if passed then be stored the image, until capturing the assigned amount. Using this method, we can rapidly capture the high quality iris images at about 0.8s, and 83% of the stored images can be used for the next procedure. At the same time, it is convenient for the user to capture.

Due to the uncertainty in the testing process of electric equipment, Bayesian network is introduced to modify the hybrid diagnostic model, and the HD-BN model is established which has the ability to deal with uncertain information. Considering the relations between functions and failure modes, the priori probabilities of failure modes are corrected, and the uncertain matrix expressing relations between failure modes and tests under uncertainty is acquired based on Bayesian inference, which lay the foundation for further optimization of design for testability.

The operating departments of power system use different information systems for work convenience. The differences in appliances, data sources, structures and maintenance personnel lead to the independence between data sources as well as heavy workload of data exchange and maintenance. The simulation of different problems needs various tools while the establishment of grid model requires hard work. This paper, on the basis of function requirement analysis, made project design of integrative simulation platform, and developed a data graphical integrated modeling platform featuring the functions of steady state, electromechanical transient and electromagnetic transient with the ability of multi-source data fusion by using the programming language C#. The platform can integrate data of PSDB, PSD-BPA and PMIS, automatically form PSASP and PSD-BPA power flow calculation data, electromechanical transient simulation data and generate “.psc” files for PSCAD\EMTDC electromagnetic transient simulation analysis according to the selected sectors and components on the graphical interfaces.

Recent years, traffic congestion is evolved into an urban disease that rejects to the urban development. Besides, it also makes multiples of exhaust pollution. To release this problem, the most effective way is to develop public transport. This paper established a model (PI) of transit priority strategies based on delay, queue length, quantities of wait vehicles, fuel consumption, CO emission, and HC emission. Among them, fuel consumption, CO emission, and HC emission are environment elements that added to this paper for the first time. After that, an evaluation is made based on cellular automata simulation, showing that the efficiency is improved by 17.7 percents when using multi-restrictions transit priority strategies, compared to that without any transit priority strategies.

A new type of small proportion double rod structure magnetorheological(MR) damper was manufactured in this article, and the damper performance test was taken on electro-hydraulic servo system. The results indicate that the damper is not only able to provide a large damping force, but also its adjustable coefficient is high. And the hysteresis curve is still good in a high-frequency vibration, so it has a good stability.

Si and C of rice rusk were used as silica source and pore-forming agent to prepare cordierite-mullite ceramics at 1380°C for 5 h soaking. The Nd2O3 additive was added to improve the sintering properties. The bending strength, porosity, and thermal expansion coefficient were measured. The composition was characterized by X-ray diffraction (XRD). The microstructures of the sintered samples were observed by scanning electron microscopy (SEM). The cordierite-mullite ceramic doped with 2% Nd2O3 have high prorosity and low thermal expansion coefficient, its bending strength reaches 20.55 MPa. The addition of Nd2O3 decreases the mullite formation temperature to 1200 °C

High intensity focused ultrasound (HIFU) is the fourth brand-new and efficient means to cure tumour acknowledged by the medical field. China is one of countries applying HIFU to clinical oncotherapy earliest in the world. However, a considerable part of HIFU equipments which have been put on the market leave unused because accidental injuries such as ambustion to the body surface, tumour tissue residues in the target section or damages to normal tissues are often caused in HIFU clinical treatment. In the thesis, temperature measurement technique of high-intensity focusing ultrasonic therapy is introduced; features and existing problems of two methods (ultrasound and MRI) which are usually used at home and abroad to guide and monitor HIFU treatment are focally analyzed and illustrated.

High intensity focused ultrasound (HIFU) is the fourth brand-new and efficient means to cure tumour acknowledged by the medical field. Study of ultrasonic transducer is a core part of HIFU technique, In order to ensure reliability and safety of treatment, it is a key for HIFU technique to realize accurate focusing of ultrasonic energy. In the thesis, ultrasonic focusing method, studies of current situations of cell and multiplex array focusing transducers and their existing problems are illustrated based on analyzing challenges faced by HIFU treatment at present. This study suggested that phased array was theoretically easy for realizing accurate control of computer， however, unbeneficial factors and engineering technical problems still exist; How to promote intensity of the focal spot of cell array focusing transducer, enlarge scope of the focal area and improve control way of the focal spot was a bottleneck problem for publicizing and applying cell array focusing transducer and one of urgent research topics for ensuring curative effect of HIFU and avoiding heat damages.

With the development of the control research, intelligent control has become one of the most popular research topics worldwide. The traditional method of Numerical simulation on control theories are realized by the programs in MATLAB, which is based on numbers of assumptions and simplification. However, it is difficult to ensure that the seismic response of the structure is always in linear elastic state during the process of hazard evolution under strong earthquake so that certain errors during such simulation are inevitable. In order to solve this problem, a numerical method of the realization of semi-active control in commercial finite element software ABAQUS is proposed in this paper. One of the main advantages of this method is that the structural plastic response can be taken into account. In this paper, the seismic response of a bridge with three-span continuous girder is numerically studied, and the semi-active control is successfully realized in ABAQUS. The proposed method can be used to carry out the refined simulation of the seismic response of the structures with semi-active control set. The highlight of this paper is to provide an effective approach for the research of intelligent control.

The aluminized 8407 steel was room temperature hard anodized for 60 min at sulfosalicylic acid concentration of 50 g/L, and current density of 2.5 A/dm2. Cross section microstructure of the oxide film and the combination status between the film and the substrate were observed with metallographic microscope. Surface morphology of the film was observed by SEM. Phase composition of the film was examined with XRD. The melting-loss properties of specimens with aluminization and oxidation treatment and without treatment in liquid aluminum alloy of ADC12 under rotation condition were evaluated by weight loss method. Sample surface conditions were observed by digital camera and microstructures of sample cross sections were observed by metallographic microscope after melting-loss test. Finally, the anti-melting-loss mechanism of oxide film under dynamic condition was clarified. The results show that the formed Fe3O4·Al2O3film can improve dynamic melting-loss resistance due to isolating steel substrate from liquid aluminum.

In this paper, a new controller of the pitch angle of the wind turbine is designed based on improved cooperative co-evolutionary algorithm(ICCEA). The ICCEA is based on general co-evolution model, and can choose evolutionary algorithm for its subpopulations independently, and regulate the probabilities of individuals production to promote the speed of evolutionary according to the characteristic of control system by introducing distribution function. The simulation results demonstrate that the proposed controller can efficiently and steady control the output power of the wind power generation system. Compared with the traditional PID controller, the controller has better control performance.

In North China, water shortage imposes constraint on economic and social development. Seawater desalination provides an effective approach to relieve this disadvantage, while this industry also accompanies with adverse environmental effects. To study the environmental impact of brine discharge from a desalination plant at the planning stage on the west coastal line of the Bohai Bay, the salinity distributions are predicted by using numerical simulation. Monthly variations of salinity distributions are given and the impacted areas are calculated. The results show that the mean area with salinity rising of 1 and 2 are about 40 and 10 square kilometers, respectively. The maximum impact areas are about 80 and 35 square kilometers respectively, which will take place in spring. The salinity variation at the inlet is predicted, which is fluctuated with the tidal oscillations, and the maximum salinity level is below 35 in this position.

This paper analyzes the optional flow chart for different kinds of tests based on hybrid diagnostic modeling technique. Furthermore, combining with varied diagnostic tests, we use the modified particle swarm algorithm (PSO) to improve the disadvantages of the traditional fault diagnosis and tests (FDT). According to the result of the filter experiment, the proposed method performs better and requires for lower ability of computation and takes less time for testing. The method can effectively optimize FDT.

Gearbox is a key part and is more easily over loaded and it has a high failure rate in MW-class wind turbine. It is necessary to analyze, predict and optimize its static/dynamical behavior. It presents the performance of one type wind turbine gearbox and the static analysis results of the housing, spline and gear pairs of the wind turbine gearbox are obtained using finite element method. The natural frequency and modal shape of the gearbox are analyzed. The modification data of the flank shape for each class tooth alignment and tooth profiles are obtained from the analysis. The related data on the strength and stiffness of all the parts in wind turbine gearbox are provided. It lays a foundation for the reliability assessment and optimization design of wind turbine gearbox.

In a rural power grid 220kV transformer substation in Liaoning Province, because of the appearance of a lot of new impact loads in the power supply area, the original reactive power repertory can not meet the existing load need. As a result, the output 66kV voltage fluctuation affects the power supply security of the users. After a comprehensive evaluation, it is planned to set up a set of ±100M SVG to increase the reactive power repertory to stabilize the system voltage. The electrical system of 220kV transformer substation is huge and often meets with sudden failure; and the capacity of this set of SVG is large, so it may worsen the situation in case of improper control. This paper discusses several operational modes that SVG should have and designs a scheme that can be flexibly switched in several operational modes, which is specifically executed by an overall coordination module. This method has passed the preliminary field operation verification.

In this paper, a layered media was used as substrate in a infiltration treatment system for municipal wastewater treatment. The efficiency of this system on nitrogen removal was compared with that by traditional used gravel and the surface characteristics of the layered media were analyzed using SEM. The results show that the layered media used as substrate in infiltration treatment system for wastewater treatment is more efficient on nitrogen removal than gravel. In the system, artificial soil provides storage for contaminants and bio-ceramics support the living organisms. The alternative running of reactor with 12 hours’ feeding followed by 12 hours’ break may supply changing environments between oxidative and anoxic in the system which is important for nitrogen removal.

TiO2 nanopowders were synthesized by non-hydrolytic sol−gel synthesis and solvothermal method. Effects of the type of alcohol on the properties of TiO2 nanopowders were investigated. XRD and FSEM were used to characterize TiO2 nanopowders. The results showed that TiO2 nanopowders with diameters of about 50nm and micro-spheres with diameters of about 400~500nm were obtained by non-hydrolytic sol−gel synthesis, when ethanol and isopropanol were used as oxygen donor and solvent, respectively. TiO2 prepared with ethanol by non-hydrolytic sol−gel synthesis and calcined at 700°C consisted only 3.8% rutile phase. After solvothermal synthesis, TiO2 nanopowders with diameters of about 50nm were obtained when ethanol and isopropanol were used as the oxygen donor. However, submicrometer spheres with uniform size distribution were obtained with 1-octanol.

In the paper, ZnO nanopowders were synthesized by one-step hydrothermal synthesis using zinc acetate and sodium hydroxide as raw materials. The influences of molar concentration of NaOH and synthesis temperature on the properties of ZnO nanopowders were investigated. XRD and FSEM were used to characterize ZnO nanopowders. The results showed that; when the molar concentration of NaOH was 0.05 mol/L, 1mol/L and 2mol/L, ZnO micrometer powders were obtained. When the molar concentration of NaOH was 4mol/L, ZnO nanorods or nanosheets were obtained with different reaction temperature. When the temperature was 220°C, ZnO nanorods with the length of 500nm and diameter of 100nm, were synthesised. Pure ZnO nanopowders can be obtained at lower temperature of 100°C by using one-step hydrothermal synthesis. When the synthesis temperature was 100°C and the molar concentration of NaOH was 4mol/L, ZnO nanosheets were produced. The length, width and thickness of ZnO nanosheets were about 800 nm, 500nm and 80nm, respectively.

Considering the nonlinearity and strong coupling of AC induction motor, a co-evolutionary control method is proposed for it，based on this method, distribution function is introduced to regulate the probabilities of individuals production to promote the speed of evolutionary according to the characteristic of control system . Compared with the traditional genetic algorithm, the searching space has been decreased greatly by the method. Furthermore, tested on AC induction motor, the controller in this paper has the traits of high-speed response and small overshoot so on.

Owing to the tamping mechanism of paving machines, the shocks towards flatiron-box are produced by compound motion of tamping beam. This significantly influences the road paving quality. In this paper, the dynamics model of double-tamper mechanism is established and the vibration process is simulated by the numerical analysis software—Matlab. Through the analysis of double-tamper mechanism, we can get the impact regularity of the vibrating beam inertia force and moment of inertia as a result of the vibration frequency and amplitude. It provides a reference for the design of double-tamper mechanism for asphalt paver and the adjustment of construction parameters.

In this paper, a new controller of the pitch angle of the wind turbine is designed based on particle swarm optimizing clonal algorithm(PSOCA), which combined the clonal selection mechanism of the immune system with the evolution equation of particle swarm optimization. The simulation results demonstrate that the proposed controller can efficiently and steady control the output power of the wind power generation system. Compared with the traditional PID controller, the controller has better control performance.

A method for indirect online over-temperature detection of isolators in high voltage switchgear is proposed，which is based on Na Superionic Conductor CO2 sensor. The over-temperature detecting principle is put forward and an over-temperature detecting system based on the method is introduced. The reliability of over-temperature detection depends on signal noise ratio (SNR), but the sensor and signal processing determine the SNR of CO2 signal. Based on quantitative analysis, it is concluded that Na Superionic Conductor CO2 sensor has higher SNR. By signal processing, the necessity of moving average filter for SNR is demonstrated. A temperature compensation circuit is adopted to eliminate the influence of temperature. In view of the characteristics of rude signal, an appropriate method of real-time digital filtering is used to improve the Signal-to-Noise Ratio. The different features of the signal under over-temperature condition have been analyzed and compared to those under normal conditions. The paper introduces a reliable algorithm for identifying over-temperature detection based on sequential section differences. Experiments prove that the method is feasible.

In contemporary electronic technology era, the volume of electronic equipment and printed circuit board reduced so dramatically that the requirements of heat dissipation and insulation increase thereafter. In this research, γ-aminopropyltriethoxysilane (KH550)-treated boron nitride (BN) powder was used as a filler to modify epoxy composites. Effects of the BN particle size and concentration on the thermal conductivity of composites were investigated. SEM image showed the treated BN filler dispersed well in the composite matrix. Moreover, the thermal conductivity was enhanced as the BN concentration was increased. Similar phenomenon was also observed when the filler particle size was reduced. Results indicated that with increasing amount of BN addition, the composites’ thermal conductivity showed a nearly linear increase. When the mass fraction of BN was 30% and its particle size was 220 nm, the thermal conductivity reached 3.4 W/(m•k), which was 17 times as high as that of pure EP resin.

The damage caused by blasting vibration on rock mass is an extremely complex process, and has certain impact on the mechanical properties and bearing capacity of the rock, which will affect the overall stability and safe operation of the construction. Therefore, studying on the damage effect of blasting vibration is very necessary. Taking Laxiwa hydropower station project as a background, the paper computed relative velocity response spectrum using monitoring and measuring blasting velocity as an excitation, then analysis was carried out to study the relationship between the depth of rock blasting and the integral value of relative velocity response spectrum as well as the index of cooperation of the integral value and the blast vibration’s duration time. The results show that using three-parameter (velocity, frequency, duration time) was clearly superior to two-parameter (velocity, frequency) on studying the damage fracture of rock blasting, and two-parameter was better than one-parameter (velocity) by analogy.