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The performance of doubly fed induction generator (DFIG) based wind turbines supplying local isolated load is manly up to the stator-voltage control strategy. Compared with conventional steady mathematic model based one, a dynamic mathematic model based stator-voltage decoupling control strategy was proposed in the paper, by which the accuracy of stator voltage was improved greatly. In this paper, the dynamic mathematic model of stator voltage and then the proposed stator-voltage decoupling control were deduced, based on which the corresponding decoupling control strategy was designed and analyzed. At last, the stator-voltage decoupling control strategy for DFIG based wind turbine supplying local isolated load was achieved. To validate the design and analysis, the simulation model was built in the Matlab/Simulink environment, and some important results were reported in the paper.

Free-piston engines are under investigation worldwide recently for their potential advantages in terms of efficiency and emissions. This paper focuses on the development and performance of a novel four-stroke free-piston generator (FSFPG), which is designed from a four-stroke free-piston engine equipped with a linear electric generator. Working principle and operating characteristics of the FSFPG are discussed, along with potential advantages and disadvantages compared to conventional engines. The design process and geometric parameters of a single cylinder, gasoline and spark ignition FSFPG prototype is presented. The control strategy of the novel power generating system is discussed. The already obtained testing results and performance of the FSFPG prototype are presented and analyzed in this paper in detail.

In this paper, firstly the operation principle of the brushless double-fed motor is introduced. Secondly by means of the single-pole slot-number phase diagram, the rotor windings are designed and analyzed, and it is proved that the designed motor can assure the equality of the induced branch EMF and satisfy the demands of other electrical properties. Finally, on the basis of analyzing the design principle of the BDFM, the Ansoft/Maxwell is used to establish the model of doubly-fed brushless machine with the wound rotor, the 2-D transient electromagnetic fields of brushless doubly-fed machine (BDFM) is calculated by finite element method, the magnetic force line and air-gap magnetic field is got, and the air-gap magnetic fields is analyzed by the harmonic spectrum. After the analysis of the finite element, the design of the BDFM with wound rotor structure can be achieved in this paper, and it provides the foundation for the rotor structure design optimization of BDFM and it also provides guiding significance for the BDFM.

Pointing on uncertainties in the velocity servo system, caused by servo system cant model accurately, may cause the deterioration of the control quality of the electro-hydraulic servo system, and even lead to its instability. Sliding model control (SMC) strategy has been application in electro-hydraulic velocity servo control. Given that the quality and stability of servo system will be affected by the chartering phenomenon in the SMC, this paper proposes an approach to overcome the chattering: dynamic sliding mode control (DSMC). In this paper the mathematical model is established and the dynamic sliding mode controller is designed. Simulation and experiment indicated that: the proposed control strategy has good performance on velocity tracking and chattering reducing .The stability and control quality of the servo system are improved.

Alternating current (AC) machine speed regulation system plays a very important role in our industrial and agricultural production. This paper focuses on the three-phase asynchronous motor which account for most of the proportion of the AC machines. Firstly, this paper establishes three mathematical models of asynchronous motor based on dq coordinate system and introduces the principle of V/f speed-adjusting for asynchronous motor, and then the paper builds the simulation models of V/f speed-adjusting control system for asynchronous motor based on Matlab/Simulink. The simulation results of the V/f speed-adjusting control system verifies the correctness of the simulation models and the principle of speed regulation.

Concerned that wind generators start up and establish the stable terminal voltage of the stator which is connected to the grid, this paper presents that wind generator can be operated as the independent generator at a certain voltage and frequency by means of capacitive excitation. The paper also deduces the calculation method for the proper capacitance value of self-exciting startup of wind generator. The paper builds a simulation model based on real time digital simulator (RTDS) and takes a case for simulating self-excited startup of wind generator. Simulation results demonstrate that the wind generator with self-excitation can successfully start up and be connected to the grid, it make a good agreement of actual situation. Furthermore, the results of RTDS simulation show that only proper capacitors value from optimized calculation can lead to a normal terminal voltage characteristic. The validity of proposal methods and designed simulation model is verified by experimental and computed results.

Situated reconstitution is proposed in this paper to cope with un-manifold polyhedral from the function to form mapping processes. Specifically the situated reconstitution is not simply re-arrangement of geometric elements, mainly face entities in the un-manifold polyhedral, rather it needs a complex geometric/algebraic reasoning to reconstitute a manifold object, novel mathematical as well as AI techniques are introduced in this paper, several tools are developed to testify the proposed situated reconstitution in the “top-down” design automation systems.

In this paper, elastic hydrodynamic lubrication theory was introduced into bearing dynamic stiffness calculation process to take into account the impact of the oil film on the rolling stiffness. Dynamic characteristics of NC boring machine spindle system dedicated to the manufacturing of bearing retainer were studied based on finite element analysis software. The rationality of the structural design of spindle was verified in the paper. The research provided a theoretical basis for the improvement of machine performance and dynamic design of NC boring machine spindle.

The sodium hydroxide calcination-hydrothermal treatment was used to modify the fly ash in this paper. The mount of alkali, the ratio of solid and liquid and the temperature of calcination were respectively studied in the process of modification. The best modified condition is that the ratio of sodium hydroxide and fly ash was 0.4:1, the ratio of solid and liquid was 1:1, and the temperature of calcination was 400°C. The zeolite-like structure was generated after modification. The modified fly ash in this paper was cheap and effective, providing a theoretical basis for wastewater treatment.

The paper aims at demonstration of reduction in residual stress, distortion and sensitisation in austenitic stainless steel pipe welds. The welding processes considered are Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc welding (SMAW) along with Hot wire GTAW with narrow gap welding technique. It was shown that residual stress is significantly reduced in case of hot wire GTAW. The reduction in residual stress is due to the low heat input and high deposition rate. Lower heat input leads to higher cooling rate giving more margins on sensitization in heat affected zone (HAZ). This has been confirmed by measuring temperature and cooling rate during welding in HAZ of the weld joints. Susceptibility to sensitization of the welds has been compared by carrying out ASTM E262 Practice A and E along with Electo-Potentiokinetic Reactivation (EPR) method. The results of the tests show that values are within acceptable limit for both the cases. However, hot wire GTAW has marginally better sensitization resistance. Fatigue crack growth rate and fracture resistance behavior of the above mentioned weld joints have been compared by carrying out tests on the specimens (Compact Tension) and full scale pipe welds with crack. Fatigue crack growth rate and fracture toughness of the weld joints (hot wire GATW) is superior to conventional GTAW and SMAW. The paper presents the details of the above mentioned studies.

In aircrafts, hydraulic systems control moveable parts. For example parts like the front strut or the landing flaps. These parts are usually made from aluminium or titanium. Due to an increasing number of functions these valves show an increasing number of cross holes. The production process causes burrs at the intersection of the holes. Until now these burrs cant be removed reliably by an automated process. Remaining burrs can influence dimensional tolerances and reduce the efficiency and technical lifetime of the component. In some applications cross holes are used for the lubricant and coolant supply. In this case burrs can lead to blockades of critical passages or cause turbulences in the fluid. This can lead to leakage or bursting of the valve. Hence an uncontrolled removal of the burr during operation must be avoided. The consequence of these basic conditions is a time consuming manual deburring process. An automated deburring process of cross holes with industrial robots is usually performed with flexible abrasive brushes. Alternatively processes like AFM (Abrasive Flow Machining), ECM (Electro Chemical Machining) or TEM (Thermal Energy Machining) are used. Those processes are very efficient but require specialized equipment and cleaning processes for the used chemicals and the remaining abrasive paste. So they are not suitable for the deburring of safety related parts. This paper presents an experimental based approach for the robot based deburring of cross holes using industrial robots. For the deburring of cross holes several special tools are available. This article gives a short overview over the specific advantages and disadvantages of these tools. As the investigations revealed the best results can be achieved using the so called Orbitool developed by JWDone. The Orbitool is a tungsten carbide cutter developed for the deburring of cross holes. A better control of the required dimension at the intersection compared to brushes and other deburring methods is possible. Furthermore the tool can be used on machine tools and industrial robots and is flexible to a huge variety of bore diameters. The tool mainly consists of a ball shaped carbide milling cutter with a protective disk which is made of polished steel and a shaft of tool steel. To remove the burr the tool is moved along the bore axis into the smallest of the intersecting holes until the tip of the tool is close to the intersection. Then the tool is moved in radial direction to the bore surface until the tool axis corresponds to the interpolation diameter. This causes a deflection of the tool. In this situation only the protective disk is in contact with the bore surface. While the tool rotates it is moved towards the intersection in a helical motion. When the tool tip has reached the intersection the cutting edges get in contact with intersection and the deburring process begins. After the tool has passed the whole intersection it stops its rotation and is moved to the bore hole centre and then moved out of the workpiece. This paper deals with the optimization of the deburring process. The result mainly depends on the parameters movement speed of the robot, slope of the helical movement and rotational speed of the tool. The experiments are planned using DOE (Design Of Experiment) methods. Initial values for the optimization of the movement speed were determined by grid encoder measurements. Robotic specific parameters like the number of interpolating points and the influence of the path smoothing caused by the controller were also investigated. For the analysis of the burr and the secondary burr an optical 3-D measurement system is used. The results show that with the presented approach the burrs can be reliably removed. Before the deburring process the average burr height is about 60 μm and can be reduced so that there is no secondary burr visible. The result is a chamfer between 150 μm and 85 μm that depends on the process parameters. It can be demonstrated that a chamfer that is smaller than 100 μm leads to a secondary burr. Anyway the cycle time can be reduced from about 3 minutes for manual deburring to 30 seconds using an industrial robot. Additional wear analysis show that about 200 bore holes can safely be deburred.

In order to improve the scientificity and accuracy of ground source heat pump energy efficiency testing, the paper discusses the principles and methods of energy efficiency testing, the requirements of the testing instruments' selection and installation and the arrangement of measuring points.The paper shows how to diagnosis instruments and process system failure according to the concrete situation on site,and points out the methods of systematic troubleshooting and fault elimination.

The complete stress-strain curve of rock is obtained mostly by the rock mechanics tester. So the rock mechanic tester is quite important in industry. It provides the scientific data for engineering design and construction. But the material of rock is made of special complex natural structure. It is very hard to obtain the complete and true performance data of rock by the common material tester which causes rock broken easily. The main cause lies on the slow response of control system, the bad performance and rigidity. In order to solve the question, this paper studies the rock mechanics tester intelligent control by computer electro-hydraulic servo device by means of computer technologies, electromechanical integration technologies and hydraulic technologies.The main work of this paper is about the modeling and simulation, mechanics of materials testing machine intelligent control to lay the foundation for further study.

An underground structure has been in a state of static equilibrium under the combined effect of gravity and the surrounding soils confining pressure before internal explosion occurred, and the blast wave can experience multiple reflections and diffractions in closed space, so the overpressure on the surface of structural members was more complex than that when explosion happened in the open space. In this paper, a finite element model of a closed underground frame structure was established by using the finite element software ANSYS/LS-DYNA. Based on the model, numerical simulation by stages was done to study the overpressure distribution on the surface of the retaining wall. This paper main analyzed the effect of the initial balance stress on the blast overpressure distribution rule and the retaining walls dynamic response.

This paper covers the results of an experimental investigation on mechanical and durability properties of concrete containing waste polystyrene based lightweight aggregate called Stabilised Polystyrene (SPS) as a partial replacement of natural aggregates. The properties investigated in this paper were water absorption by capillary action and total absorption, compressive strength and ultrasonic pulse velocity (UPV). The composite aggregate was formed with 80% waste polystyrene which was shredded to different sizes, 10% of a natural additive to improve the resistance to segregation and 10% Portland cement. The natural fine aggregate were replaced with 0%, 30%, 60% and 100% (by volume) of SPS. There was an increasing in water absorption and a decreasing in compressive strength and UPV with the increase in SPS aggregate content in concrete.

This paper researches laser marking machine and fuzzy control system, and belongs to the optical fabrication. This paper combines fuzzy control system with laser carving system, and greatly improves the machining precision. This paper introduces laser precision system about optical fiber laser of the output wavelength of 1064 nm, researches that application fuzzy technology controls the servo motor, drives moving workbench, strictly control the location accuracy, so as to realize the precision intelligent control of laser engraving machine. Using the computer marking card and servo drive system technology, this paper achieves joint control both laser engraving signal and servo system, solves the intermittent fit between the laser precision system out light moment and ruler feed stop, researches intelligent system is developed for laser precision stability control system, and achieves caliper precision engraving. Computer connects to the network to realize remote monitoring. System is stable operation, strong ability to adapt the environment, high efficiency and precision.

The paper starts from from the rotor unbalance fault, and analyze the reasons of unbalanced rotor are improper design, material defects, process and assemble error, process problem; Summarizes the frequency spectrum characteristics of rotor unbalance, its features, frequency components of speed have protruding peak on spectrum diagram of detection in radial direction;Puts forward the diagnosis methods of Unbalanced vibration, the first step is to analyze vibration signal frequency components, then analyze its characteristics of vibration in the direction of the change of amplitude and phase. Proved by examples, this paper summarizes the rotor unbalance analysis and diagnosis method is simple and practical, and has reference significance for other vibration problem.

One of the reasons of chemical explosion is the grease enters the oxygen cylinder when fill and use it. The grease in the cylinder will be oxidized, which can elevate the temperature. The high temperature will decrease the ignition point of grease, and then the combustion and explosion will occur. To prevent such accidents in the cylinder filling process, the temperature of the gas in the cylinders must be strictly controlled. In this paper, the heat transfer of the cylinder wall is studied by the method of calculation and the pressure-temperature law of outer wall of the cylinder is obtained. Therefore, this paper provides a reference for chemical changes in the cylinder filling process. The grease should be degreased first before the cylinder filling process. The temperature of cylinder should always be ensured normal during the cylinder filling process.

Incomplete fusion and incomplete penetration are two types of damage serious welding defects. These two kinds of defects have the similarity in the features in X-ray imaging. Identifying the two kinds of defects automatically and accurately can improve the welding technology and improve the quality of welding effectively. The causes of defects and features of X-ray images are described in the paper. The welding defects calssification method based on multi-weights neural network is put forward in the paper. The multi-weights neural network based on graphic geometry theory is introduced, which uses the geometrical shape in high dimensional space to cover the same class defect samples via constructing multi-weights neural network. The experimental results proved the effectiveness of the algorithm.

A type of pneumatic force servo system is discussed in this paper. In this system, output pressure depends on pressure difference between two chambers of cylinder; by controlling pilot-operated reducing valve will get different cylinder chamber pressure. Dynamic mathematical model and control Strategy of this system is founded in this paper. By mathematical model and control Strategy, the digital simulation results show how system performance with different gas source pressure and rodless cavity size..

It is become a relative mature technique now that Active Power Filter can do harmonic suppression and reactive compensation to alternating current net of nonlinear load. This paper contrasts passive and active filter technology in harmonic suppression, and introduces the classification of passive filter as well as working principle. This paper also discusses current-source APF consisting of multi-modular and phase shifted SPWM converters and cascade multilevel converters applied in current-source APF which can carry out high switch frequency effect under the lower switch frequencies. Finally, this paper gives a comprehensive discussion on APF technique and prospects its development in China.

This paper presents a relay selection method for radio and television business, this method uses nodes time-delay and power information, obtains the value of network interrupt as decision threshold, then selects the relay node. At same time this paper proposes an optimal relay selection strategy which can minimize the network interrupt probability combination with power distributionMulti-Path Relay Routing Protocol, this protocol can change the appropriate route path according to the dynamic network. Simulation results show that this protocol can extend cells coverage area, reduce time-delay and increase system throughput, improve system spectral efficiency, and enhance Qos of radio and television business.

In this paper, a water-lubricated hybrid with four stepped recess supporting a high-speed spindle system is studied. A two-dimension finite element method considering turbulence effect and the relationship between temperature and viscosity is developed to solve the Reynolds equation to obtain different bearing performance. This paper mainly discusses the influence of the water supply pressure, rotating speed, and load carrying capacity on the power loss, friction coefficient and temperature. The results presented in this study are expected to be useful for the design of water-lubricated hybrid bearing used to support high-speed spindles.

This paper presents an algorithm to measure geometric parameters of optical fibers based on Halcon. The algorithm enhances the contrast of the fiber image and uses canny edge detection operator to extract the contours of fiber cross section. In order to remove noise in the contour, this paper studies new methods, include setting the contour length range, whether each contour is circular or not and whether the center of the circular contour and the center of the fiber core is consistent or not. These methods remove most of the noise. Finally, the effective contours are merged and then approximated by circle and ellipse. According to the mathematical model, all parameters required can be obtained. Experiment results show that the algorithm accuracy meet the needs.

The electromagnetic force which influenced by rail launcher armature position have been researched in this paper. As an important indicator, Inductance Gradient (IG) denotes the performance of rail launch, which can make the railgun performance to achieve optimal results by better design. A rectangular cross-sectional rail launcher model was built based on the Biot-Savart law in this paper. Furthermore, the analytical expression of inductance gradient can be obtained by this model. Finally, the electromagnetic force can be calculated. Some numerical simulations are made to test the validity and capability of the proposed model.

This paper evaluates the results of two recent studies of advanced amine-based, post-combustion CO2 capture plant designs. The first study was conducted by the IEA Greenhouse Gas R&D Programme (IEA GHG), while the second study was conducted by Parsons for the US DOEs National Energy Technology Laboratory (NETL). Fluors improved monoethanolamine (MEA) process, known as the Econamine FG PlusSM technology, is utilised for both studies. Cost and performance estimates for both pulverized coal and natural gas-fired combined cycle plants are summarized. Differences between the design bases and assumptions for the two studies are discussed. The Econamine FG PlusSM technology, as an improved process in amine-based post-combustion CO2 capture described in this paper is leading to lower increases in the cost of electricity (COE). Both the DOE/Parsons and IEA GHG studies show that the increase is now down to 42 to 43% from as high as 60 to 70% indicated from previous studies for PC plants with CO2 capture.

Cement hydration products carbonation is not only blamed for the carbonation-induced hardened cement paste or concrete cracking, also attributed to the pore water PH-value decrease, which causes the reinforcement corrosion under the existence of water and oxygen due to removal of oxide film passivating rebar surface, in hardened cement paste and concrete. Based on chemical thermodynamics, this paper presents the susceptibility of different cement hydration products to carbonation through calculating their Standard Gibbs Free Energy respectively, Gibbs free energy under temperature variation and the minimum equilibrium pressure of carbon dioxide triggering the carbonation process. The calculated results show that, under standard state (25°C, 100kpa), the minimum equilibrium pressure of carbon dioxide triggering carbonation process is significantly variable for different types of cement hydration products. For example, mono-sulfate sulfoferrite hydrates (3CaOFe2O3CaSO412H2O) is the most susceptible to carbonation, followed by mono-sulfate aluminate hydrates (3CaOAl2O3CaSO412H2O), while multi-sulfate sulfoaluminate hydrates (3CaOAl2O33CaSO432H2O) is the least vulnerable to carbonation, followed by silicate hydrates (5CaO6SiO25.5H2O). The findings in this paper are significant in understanding thermodynamic mechanism of cement hydrates carbonation and seeking the solution to prevent cement hydrates from carbonation-induced deterioration.

In this paper are presented information about common and advanced materials used for manufacturing of products by Fused Deposition Modelling (FDM) rapid prototyping technology. In different rapid prototyping technologies the initial state of material can come in either solid, liquid or powder state. The current range materials include paper, nylon, wax, resins, metals and ceramics. In FDM are mainly used as basic materials ABS - Acrylonitrile Butadiene Styrene, polyamide, polycarbonate, polyethylene and polypropylene. Main part of the paper is focused on experimental testing of rapid prototyping materials realized by different research teams and presents outputs of testing of ABS material in FDM technology realized by authors.

An effective method for low perming error of fluxgates is to enlarge the peak value of the excitation current, but large amplitude excitation will increase the power consumption. A narrow pulse excitation current with sufficient peak value can reduce perming error with low power consumption while increase the difficulty of the signal processing with low sensitivity. The perfected excitation waveform with high ratio of peak value to RMS value by careful excitation tuning is an efficient solution. This paper presents a novel circuit which can generate an excitation current waveform with high peak value and low RMS value for fluxgates. Different from the tuned excitation circuit, the proposed circuit is a combination of an integrator and a differentiator with the same squarewave input. The excitation signal is the sum of a triangle wave and a sharp narrow pulse signal. It is easy to adjust the peak value of the narrow pulses for perming error study and no careful tune adjusting is needed. Finally, in case of the fixed peak value of the narrow pulses, an improved excitation circuit with only two resistors, two capacitors and one amplifier is also presented in the paper. The experiment results show that 0.5nT perming error can be achieved for 10mT shock.

This paper analyzes the influence of lubricating oil film of the low-speed and heavy-load sliding bearing on a variety of factors. It introduces the operation of Bearing for lubricating oil film in monitoring method, common fault causes and treatment measures. Finally, the bearing cooling system structure is discussed, providing reference for practical engineering application. There are many reasons to cause the failure of the bearing lubrication such as bearing assembly defects, the error of size and cooling system problems. By detecting and contrast parameters, this study analyze the determine data and correct the fault. Through the use of reasonable structure of the oil tank and cooling water channel, we can improve the lubrication performance, and extend the bearing life. This paper analyzes the factors restricting the low speed and high load sliding bearing lubricant film, and solves the actual bearing lubrication problem.

Communications on the Move (COTM) has gained a great deal of attention recently. The need for broadband connectivity from a moving vehicle has increased dramatically in the past few years for both commercial and military applications. This paper will discuss elements and considerations of providing satellite communications on a moving platform from a system perspective. It will focus on Internet Protocol (IP) over satellite since IP has become the dominant protocol for newly deployed voice and video applications. A global COMT network has much great degree of complexity than a regional network since it will require beam switchover and IP routing re-convergence as a vehicle moves from one satellite beam to another. This paper will present some approaches to COTM system design including antenna size and link budget, spectral density, the Doppler effect, beam and teleport switchover.

This paper studies experimental methods to measure friction, which determines the wear of chain elements in relative motion from a chain transmission, used in camshaft drives for an internal combustion engine. The paper presents a critical analysis of a constructive solution realized to determine the friction torque in parallel axes transmission bearings.

The material damages in aerospace industry caused by correction can be detected in many different products including welded and bolted areas in aircraft and jet engines. The corrosion occurs when different conducted materials contact to each other in electrolyte media and different conducted materials present potential difference that causes rusting. The rusting problems in products lead both safety issues and billions of dollar loss in different businesses including aerospace industry. This paper studies the rusting mechanism and anti-corrosive coatings by applying computational simulation and prototype experiment. Both computer-aided analysis and sample testing demonstrated similar results which confirm the feasibility of analytic methodology introduced in this research paper.

For the thin film lubrication, boundary lubrication, and local dry friction lubrication state of hydrodynamic bearing, a lubrication model of distributed liquid film is established in this paper which is designed to service for calculating or predicting the full life cycle design performance of water-lubricated bearing. The limitations of the fluid-solid-thermal coupling model for describing the distributed liquid film are investigated. Two new methods to build the lubrication model of distributed liquid film are given. The first one takes fluid-solid-thermal model that can guide the design of bearings parameters as dominant factor, and combines with wear, corrosion, two-phase of gas-liquid and other additional factors. A comprehensive model integrating simulation and mechanism can be built. Through researching the regional properties or distributed parameter of water film and solid interface, the second way proposes a decomposition and synthesis modeling method of water film and rubber. A distributed parameters model of dynamic characteristics for water-lubricated bearing is built. The lubrication theory of distributed liquid film proposed in this paper is appropriate for the situation when the film thickness is less than 10μm or contact. When the film thickness is greater than 10μm, classical lubrication theory is applicable.

Nuclear energy is a carbon-free, clean and efficient energy. It is very important in the progress of human civilization and modern development of the world, however, there are still some problems such as nuclear leak and nuclear waste. In this paper, the worlds nuclear energy utilization and nuclear power plant constructions are reviewed and plans are forecasted. The basic reason of previous nuclear power plant accidents in history is summarized. Taking 2011 Tohuku earthquake-fukushima nuclear power station accident as an example,threats to the nuclear power plant by earthquake are investigated and impacts on social, economic and ecological environment caused by nuclear power station accident are analyzed. This paper drew lessons from previous accidents and put forward a variety of countermeasures which are from both the technical and management aspects. We also appeal people all over the world to respect the nature, enjoy the nature, and to create and enjoy the new civilization of human beings.

The non-smooth surfaces on 45 steel were prepared by laser cladding with KF-300A alloy powder on the basis of the bionic non-smooth morphology of shark scales. The rib-type coatings were composed of hot-rolled steel 45 and clad layers containing hard phases such as WC/W2C. In this paper, the influence of laser power and defocusing distance on the quality of cladding layer were investigated. The microstructure of the coatings was analyzed by scanning electron microscopy, with attached energy dispersive spectroscopy microprobe, and by X-ray diffraction. SEM inspection of the samples showed that all coatings exhibited similar phases in their microstructure, but the phases presented differ in morphology, size and distribution. Dilution and interaction zone of the coatings were also discussed in this paper. The results showed that the non-smooth coatings were crack-free and had a good metallurgical bonding with 45 steel trenches with a low dilution under the optimum laser conditions (P=700 W, f =14 mm, V=3 mm/s, continuous powder feeding voltage 2.1 V, nitrogen protection).

This A new method of magnetic levitation micromotion of AC / DC hybrid driving is presented in this paper presents, and a new magnetic levitation micromotion stage has been designed, which can be realized that the motion stage translationally motions, respectively along the three directions x-axis, y-axis, z-axis, and rotates respectively around the three directionsθxθyθz, namely, the micro-motion in the six-dimensional space of freedom, as well as the micro movement of the constant height. Force analysis has been carried out on the micromotion stage, and the relationship curve between the winding current and the air gap, as well as the force of the micromotion stage, has been drawn. Finally, the stability in the open-loop state and one-dimensional micro-movement of the magnetic levitation micromotion stage have been tested. According to the simulation result of the stability ,it shows that the stability of the magnetic levitation micromotion stage can be achieved at the equilibrium position, and according to the simulation result of the one-dimensional micro-movement ,it shows that the motion range whthin 50mm along the direction of x-axis can substantially coincide with the theoretical analysis. The feasibility of the design presented in this paper of the magnetic levitation micromotion stage can be validated by the simulation result of the stability and one-dimensional micro-movement.

This paper established a transformer substation comprehensive optimal planning model considering distribution generation (DG) and different block geographic information factors (GIF), set form, volume, location of existing DG in planning area and transformer substation load-bearing capacity as constraint condition, taking construction cost of distribution transform substation and feeder and operation cost including current supply loss into account, in the meantime, regarding the influence of GIF such as land properties and so on to location and cost of construction with load demand satisfied. Furthermore, influence factors of different block information factor to construction cost were work out by means of interval analytical hierarchy process. On the basis of the established objective function, an particle swarm optimization (PSO) algorithm is proposed to solve the problem in this paper. By empirical study of certain planning area, the proposed model and algorithm are proved to be scientific and effective.

The paper deals with solutions to particular process problems in production of thin sheets of special nickel and iron-based alloys. Experiments were focused on trial operation of a new melting furnace, on hot rolling of feedstock from experimental heats and on fine-tuning hot and cold rolling processes with the aid of numerical modelling in DEFORM 3D software. The paper also gives description of results of FEM simulation of cold rolling of strips. A FEM model of the cold rolling process with front and back tension was developed. In order to describe the behaviour of nickel alloys in the FEM simulation, a specific material model was proposed. This material model combines the material data obtained from Rastegaev compression test and the results of thermodynamical calculation from JMatPro software.

This paper studies on a new type design of a real-time monitoring and fault diagnosis system of equipment. The system uses subject knowledge, such as sensor technology, neural network and embedded systems. It regards system voltage and current as the monitoring goals at the same time and shows the text of the system malfunction on the liquid crystal display. The paper introduces a new system monitoring approach combined with text, sound, light alarm to achieve the goal that the process of operating the equipment is safe, stable, balanced and low loss.

t would be a large effort to use traditional methods of calibration procedures for Web Offset Press equipments. In this paper we proposed a convenient process calibration, which will not only guarantee the product quality meeting the ISO standards, but also save financial and material resources. Firstly, the measurements for determining the best ink thickness in Web Offset Press are discussed. The chromaticity values on solid fields with corresponding combination of paper and ink required by ISO Standards were achieved. Through a optimization process for gray balance, the printed tone values were adjusted to meet the requirements of ISO Standards. Finally several standardized test targets on sampled sheets ware measured, then the ICC profiles were created. This paper proposed an innovative process calibration, therefor using methods of chromaticity measurement, characterization of Web Offset Press can be put to effect to optimize printing processes.

In the production site, making navigation bar is very important. A good navigation bar determines the style of the page and the page level of clarity. This paper introduces a method of making a horizontal navigation bar. And this paper uses the CSS + DIV corresponding effect.

To solve the bottleneck problem of defining motion trajectory of virtual role in animation creation process, this paper presents a solution of mechanical human body motion capture technology, mainly involving inertia sensing technology, Bluetooth, the design of sensor network nodes and the development of reconstruction software of human body motion model. The system uses sensor network to collect motion data of the body key joints, and the data are delivered to workstation through Bluetooth, the software on workstation uses analytical inverse kinematics algorithm to analyze the motion data. So the system has advantages of lower cost and high precision. Meanwhile, the paper also provides a solid foundation for the research of multiplayer real-time motion capture technology.

The traditional antenna is made up of metal or solid dielectric material, seawater is a new type of dielectric material for antenna. In this paper, numerical method (MoM) is used to calculate the input impedance of antenna formed by seawater, we compare its performance with traditional metal antenna while their radius and heights are changed, discuss its effect of input impedance and get the meaningful results, raise the application prospect of seawater antenna at the end of this paper.

Linear servo system is an important part of numerical control machine tool, and its performance and quality will directly decide and affect the rapidity, stability and accuracy of numerical control device. The servo system made up of linear motor can realize zero transmission between motor and worktable with various advantages as fast response, high efficiency and position tracking precision. In this paper, the permanent magnet linear synchronous motor is used as actuator, and according to the idea of space vector decoupling control, the linear servo control structure is established based on position proportion adjustment and speed IP adjustment. On such backgrounds, the paper studies the iterative learning control method so as to realize the perfect position tracking ability and robust performance of the system. Chinese Library Classification: TG659

This paper investigated the cause of the harmonic current amplification in nonlinear load in a 6kV substations power supply system. The paper proposed that reactors could be series connected in the capacitors by-pass to restrain the amplification. The result from field practice showed that this method could overcome the harmonic current amplification efficiently.

In recent years, the laser fuze has been widely used in minor caliber mortar projectiles and bombs because of its high accuracy in distance measurement, strong ability to resist electromagnetic interference, high angular resolution and good concealment. As a result, it becomes an irreversible tendency to miniaturize the high power of the laser, especially in military applications. This paper aims to study the factors on the output characteristics of the microlasers. Based on the variation of the inversion density of the particle in the resonant cavity derived from the oscillation equation of the LD-pumped passively Q-switched Cr4+:YAG/ Nd:YAG laser, this paper summarizes some key factors which have impacts on the output of LD-pumped passively Q-switched subnanosecond microlasers, including the initial transmission of the absorber, the reflection of output coupler, the length of the cavity and the radius of the pumping laser beam, and gives the conclusion of the simulation, which provides the basis for the design of the passive Q-switched micro lasers which have high power, high repetition frequency and narrow pulse width.

Based on force analysis of angular contact ball bearings, this paper proposes a generic mathematical modeling method. This paper conducts in-depth research for these aspects: all directions of the stiffness characteristics under different load conditions of angular contact ball bearings, internal contact deformation and the change of bearing parameters. This article eventually gets the variation of the bearing characteristics under different load conditions.

This paper studies the positioning method of DPM 2D barcode image. Because of the reflective problems of metal surface, the barcode image gotten will have uneven illumination, high light issues. In this paper, the homomorphic filtering method is used to enhance the image. Then the gradient projection is used to positioning the barcode region preliminary. We use an adaptive threshold method composed of Otsu method and neighborhood threshold method to solve the error segmentation problem. Finally the convex hull algorithm is applied to locate barcode region. Experiment results show that this method can effectively locate the barcode region quickly.

This paper reports the results of experimental research concerning the connection between the deck plate and the web of the longitudinal stiffeners in an orthotropic plated bridge deck on a microscopic scale. An important number of test specimens of a weld are studied with the help of a video microscope, to detect the efficiency of the root of the weld. The second part of the paper is concerned with parametric analysis of the lack of weld penetration by using accurate finite element modeling. The results demonstrate that the weld quality often required cannot always be assured, which surely has important consequence on the stresses in the weld and the fatigue resistance.