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Because of the advantage on energy saving and environmental sustainable development, the ground source heat pump (GSHP) system has received the widespread attention and application in recent years.However,the difference between cooling load in summer and heating load in winter is obvious in most areas of our country,so it can cause the heat accumulation around ground heat exchanger,which will result in degradation of system performance and increment of system operating costs.To solve the problem of thermal imbalance,it is necessary to research the soil temperature field around the buried pipes in the process of system operation.This paper begins with a review of the studies about the ground source heat pump systems.This is followed by a review of various methods of enhancing the performance of heat pumps based on the thermal imbalance.And then,this paper shows some studies about ground source heat pump systems based on the groundwater seepage.

In this paper, the basis function of TDCS system (Transform Domain Communication System) is used to design cognitive radar transmitter waveform. Based on the noise environment, the waveform can be adjusted adaptively. Then after clipping to reduce the PAPR (Peak to Average Power Ratio) of radar echo signal, the obtained signal is used as the next launch of the radar signal. The cognitive radar transmitter requires a nonlinear waveform to improve the efficiency of radar transmitter power amplifier, so reducing the PAPR of signal is essential. This paper presents the gray complementary sequence is applied to TDCS communication systems, and then it needs to reduce PAPR of signals by clipping. Proven, PAPR of the transmitted signal is maintained at about 3.25dB, and the signal has a low probability of intercept, high anti-interference ability and distant target detection range.

CFD is the abbreviation of the computational fluid dynamics, which is widely used in engineering fluid simulation. Based on two-dimensional N-S equation and k-e turbulence model, this paper uses FLUENT software, finite volume method and SIMPLEC algorithm to do numerical simulation and analysis on flow field in centrifugal fan. In order to improve the efficiency and accuracy of calculation, this paper uses AutoCAD to establish the two-dimensional model of fan, and uses the structured triangular mesh to divide grid. Encrypting the blade can improve the precision and also save the computer memory. Through the calculation we get the internal flow field velocity and pressure distribution in the wind turbine, and get the power level cloud of internal noise in fan. It provides the technical reference for the optimization design of wind turbine.

This paper contains the results of research, carried out with financial support from the Ministry of Education and Science of the Russian Federation (contract ID RFMEFI57914X0026). For the ground source heat pump (GSHP) used as a heating system in regions with cold climate the thermal effects of ground moisture freezing-melting processes can make an essential long-term impact on GSHP performance. However, widely known models of heat transfer inside and outside GSHP borehole do not take into account such effects. In this paper we propose a method of engineering estimation of freezing-melting latent heat in the frame of modified cylindrical source model. The key feature of the method is the definition of effective thermal conductivity of ground to "convert" the latent heat of phase transition into equivalent heat flux from outer ground. The method is validated by laboratory measurements of ground thermal conductivity during the freezing-melting process.

The paper investigates the Multi-FPGA systems structure, including interconnect and configuration structure of the systems. After analyzing several common FPGA systems interconnection structure, we present its features. The paper analyses the feasibility and technical advantages for FPGA systems to use in digital array radar receiver design, and discusses their specific implementation, and designs a set of IF receiver with twenty reception elements.

With the improvement of computer hardware and software performance, digital multimedia technology has been applied to various fields. The visual effect of ceramic art image is affected mainly by the brightness, texture and color, in which the image defects will affect the visual effect of the ceramic product. This paper designs the digital processing system of a new ceramic art image processing, the system can repair defects in ceramic art image. In order to verify the validity and reliability of digital processing system, the lead-free perovskite structure BZT based ceramics is prepared in this paper, and the use of electron microscope and digital camera take the ceramic products processing image with artistic defects, and then using VB programming digital image processing technology carries out color re coating for the ceramic, the ceramic products electron microscopy images after restoration will be obtained by the image boundary restructuring, which provides a new computer method for the processing art of the ceramic products.

With the development of modern aviation technology, the structure of aircraft engine as the heart of the plane is more and more complicated. The problem of people’s concern is how to monitor engine condition and realize the fast fault diagnosis of engine. In this paper, the method of support vector machine (SVM) combing evidence theory decides whether a signal is a fault signal on the base of researching the engine vibration mechanism and the characteristics of rotor fault vibration signals. This method avoids the defects giving the single information though the traditional method which is unable to predict the tendency of the engine safety. Evidence theory meets weaker conditions than Bayesian probability theory. It can express "uncertain" and "unknown" directly. Therefore the paper makes information fusion in combination with evidence theory in different measuring points and different working conditions of engine. This method not only can identify small sample and nonlinear system, but also fuse information which gets more evidence samples effectively. At the same time, the posterior probability diagnosis results can predict the development trend of the fault accurately. Output in the form of probability can deepen the cognition about the present situation of the engine and better observe the safety of the trend of engine simultaneously. It can facilitate the management and protection in time.

In this paper sustainable analysis is performed due to the increasing demand for fuel efficiency. Current research focuses on high strength-light weight components in automobile which lead to the development of advance material parts with improved performance. A specific class of advanced material which has gained a lot of attention due for its potential is aluminium based metal matrix composites (Al-MMCs). Al-MMCs have some prospects for several applications in automobile parts. The analysis in this paper is a part of product development which plays a crucial role in determining a product's environmental impact. The objective was accomplished and thus to identify the potential of Al-MMCs rake disc for replacement of the conventional cast iron brake disc. The result indicated that the Al-MMCs have the potential to substitute the cast iron brake disc.

This paper presents the speed performance of an induction motor by using a vector control. The control scheme used is an indirect vector control for define speed command. The main focus of this research is to observe on the dynamic speed performance of the induction motor when the command speed is given to the motor. In this study, the system of indirect vector control will be built by using Matlab Simulink. In fact, the expression of exciting flux linkage and electromagnetic torque are used to create a simple embedded system which to find out the effects of flux weakening in motor while, the gain of the speed controller is 100. The result shows that the vector control method will cause immediate the motor speed response with a small electromagnetic torque ripple. Furthermore, the output mechanical torque starts to decrease when the motor speed above the base speed to maintain a constant output power operation. This paper contributes a new algorithm to analysis the system when the speed motor is higher than a base speed.

This paper analyzes and studies the definition of the voltage transformer secondary load, examines the practical purposes of the measured values of the voltage transformer secondary load, and presents a variety of testing methods to analyze and compare the differences. This paper gives the test methods of the voltage transformer secondary load when the connection of the voltage transformer is the Y / Y in a three-phase three-wire power supply system, filling the blank of this type of test method in the industry. When other units within the industry carry out such work, the conclusions of this paper are available for reference, and the conclusions of this paper can be referred when drafting relevant regulations in the future.

There is a large potential in the heat loss from the urban wastewater. In all kinds of low-grade heat sources, urban wastewater is gradually widely used because of its advantages such as huge quantities, small variation of temperature, warm in winter and cool in summer, etc. By integrating a heat pump to utilize this heat, the wastewater source heat pump (WWSHP), which is a new water reuse and treatment strategy to tackle the water problems of China and to realize the sustainable development, recovers the heat of wastewater. The WWSHP air conditioning system as residential application can reduce the need of energy systems based on fossil fuel for cooling, heating, and hot water's supply purposes. The system's working principle, classification and the wastewater's characteristic parameters were discussed in this paper. And the scheme of using WWSHP system for central air-conditioning compared with other refrigerating and heating equipments was analyzed in detail. The investigation into COP (Coefficient of Performance) and PER (Primary Energy Ratio) was shown in this paper. Among the four kinds of common air conditioning units, when the loads are same respectively, the WWSHP has the most significant energy-saving effect. Furthermore, mechanism of heat transfer enhancement for falling-film evaporation and condensation surface of tubes packed with wire-mesh is also studied in detail. Theoretical simulation will be carried out for the heat transfer process and the flow of falling-film outside horizontal tubes. Improvement of controlling parameters influenced the evaporation and condensation performance, and then led to an increase in the refrigerating quantity and the COP. Consequently, this WWSHP system has its theoretical significance and promising engineering application potentials for the residential refrigerating and air-conditioning system using low-temperature waste heat source.

The paper makes the simulation and analysis to the power harmonic which is produced by the AC drive device of the hot strip mill in the background of the metallurgical industry. Aiming at the line-side effects of AC-AC frequency conversion and AC-DC-AC frequency conversion control system harmonic, the paper makes the MATLAB simulation and analysis in three circumstances, such as the load parameters, the inductance value changes of transformer primary side and secondary side, and adding reactor etc., and defines the functions and value ranges of the line reactor. The simulation results can provide a design basis for the harmonic control and the power supply system when the system uses the variable frequency devices, and then improves the power supply quality of the large drag device.

This paper demonstrates how to use CAD Software (Pro/ENGINEER in our case) to generate a cam profile. This cam will be used in a five bar linkage for which the input elements are synchronized through a cam-follower mechanism. The cam profile is generated so that the five bar mechanism produces a certain curve. The paper presents the synthesis method after which a simulation is executed to verify the results.

The complex geographical environment put forward grand challenge to most current detecting robot on the problem of communication control and moving obstacle avoidance.This paper proposed a crawler robot for complex environment detecting.Information acquisition was achieved by Labview programming,the collected sensor information was debugged by fusing and displaying in the Labview interface , in order to realize the stability of the system.The positioning part adopted wireless location technology of ZigBee networks,which can support a large number of network nodes, fast, and reliable security etc.In addition, the upper part of the robot body was equipped with camera and mechanical arm to achieve target capture, carrying something and other tasks. According to the situation of accident, remote control terminal through wireless control function can control the further action of the robot. Through experimental tests, this paper proposes this kind of detection robot had great advantages in detection, search and rescue, it can complete the search under complex and dangerous environment.

This paper contains the results of research, carried out with financial support from the Ministry of Education and Science of the Russian Federation (contract ID RFMEFI57914X0026). For the ground source heat pump (GSHP) used as a heating system in regions with cold climate the thermal effects of ground moisture freezing-melting processes can make an essential long-term impact on GSHP performance. However, widely known models of heat transfer inside and outside GSHP borehole do not take into account such effects. In this paper, we propose a method of engineering estimation of freezing-melting latent heat in the frame of modified cylindrical source model. The key feature of the method is the definition of effective thermal conductivity of ground to "convert" the latent heat of phase transition into equivalent heat flux from outer ground. The method is validated by laboratory measurements of ground thermal conductivity during the freezing-melting process.

Quantitative measured values for absorption of copper and its alloys are jet unknown in the temperature range between 30 °C and 500 °C which has to be passed before material melts in the initial phase of laser beam welding. Thus this paper investigates temperature and wavelength dependent absorption for VIS and IR wavelengths. For this purpose specimens of copper and copper alloys are heated up and reflected laser light from the surface is measured by using an Ulbricht sphere in combination with a photodiode. During welding processes inert gases are in use to reduce oxidation. Hence the influence of shielding gases on the absorption will also be taken into account during the heating process of the specimens. Consequently this paper provides results for the temperature dependent absorption of copper and copper alloys for different wavelengths at atmospheric conditions and argon shielding.

The water droplet erosion protection of the rotor blades has been an important issue for a long time, regardless of the design. The aim of this paper is to present a aerodynamic design method for decrease risk of water droplet erosion in wet steam turbine, as well as to present the comparison between then five diffrent bow stator blades. This paper also presents numerical investigation of three dimensional wet steam flows in a stage. This stage has long transonic blades designed using recent aerodynamic and mechanical design methods. The results show that, the one of the five diffrent bow stator blades decrease rist of water droplet erosion of rotaional blades, and the change of the efficiency is small.

According to the structural characteristic of LNG cryogenic storage tank concrete prestressed wall and heat transfer theory, the paper obtain the calculation formula of the temperature field distribution, emphasis studying the heat flux distribution along the radial and axial and node temperature distribution of the section nodes for a 160,000 m3 capacity LNG cryogenic tank by ABAQUS. The paper also establish a set of method which is suitable for the temperature field analysis, proof the feasibility of finite element analysis technique in the analysis of the LNG cryogenic storage tank, and have a certain reference for the prestressed concrete walls and insulation layer design of the large LNG storage tank.

This paper proposes a solar-air compound source heat pump system, for the rural residential area of Hebei and independent villas. The system can realize heating in winter and refrigerating in summer, and demand of heat water. This paper simulates and analyzes the winter heating situation of this system. The entire heating season, heat collecting efficiency of the solar collector is 0.45 in average, and solar guarantee rate is 46%. Solar-air compound source heat pump system average COP is 4.5 in the heating season, increased by 26% than the air source heat pump system run separately , and the fluctuation range is small. Throughout the heating season, the contribution of solar collectors is 59%, the contribution of air source heat pump is 41%.

The paper presents new methods and procedures to measure the characteristics of laser beams and their transmission through optical systems. The paper describes the work procedures and equipments used to measure the characteristics of laser beams and their transmission through optical systems. Using these working procedures, experimental measurement for the characteristics of the beam for a 1.54 µm laser rangefinder and the transmission of a 633 nm laser beam through laser protection glasses were made.

This paper presents the results of an investigation on the effect of air filter elements on the performance of spark ignition (SI) engine. Three different types of material; paper, cotton and foam were tested as filtering element in the air filter before the mixing process with fuel in the carburettor. In the experiment, a four-stroke single-cylinder engine was coupled to a 20 kW generator dynamometer to measure engine performance parameters; engine torque, engine power (B.P), brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) at various engine speeds with maximum engine load. The results show correlation between engine performance and the qualities of filtered air as a function of type of air filter element/material used.

This paper present a procedure to detect wear or corrosion in structural elements based on frequency changes. Several methods to damage assessment are known, but these are mainly addressed to open cracks without considering the loss of mass. Since the mass decrease is a phenomenon associated with numerous corrosion mechanisms, the idea of this paper was to establish the influence of mass changes upon the natural frequencies of beam and to use it as a baseline in damage detection methods. Consequently, the research was conducted in two steps; first we analyzed the beam dynamics for a segment with reduced volumetric mass density but maintaining the global beam rigidity, succeeding to find the correlation between the frequency changes in the transversal vibration modes and mass loss in form of a mathematical relation. Afterwards, this relation was incorporated in the relation who predicts the frequency decreases due to stiffness diminish, in order to fit it for wear and corrosion assessment. The method’s robustness and reliability was proved by FEM simulations as well as by experiments.

In this paper, voltage fluctuation and stability analysis of critical buses was performed using multiple indexes to power system with wind farm connected. Considering the intermittency and randomness of wind speed, this paper constructed three voltage fluctuation indexes according to the characteristic of voltage random distribution. Bus voltage stability index was also calculated with the help of PV and QV curves in the paper. The simulation analysis performed in the DIgSILENT/PowerFactory basing on three machines nine nodes system with double-fed wind farm was carried out to reveal the impacts of wind generation uncertainty on voltage fluctuation and stability.

Transformer is one of the most important equipment in power system, and accurate condition assessment for transformer is the key for condition based maintenance (CBM). So the study of condition assessment is particularly important. In this paper, the function, role and steps of condition assessment, research status, existing problems and future directions are analyzed and summarized. And this paper can be a reference for transformer’s condition assessment.

The formability of tailor welded blanks is significantly reduced compared with the homogeneous blanks. This phenomenon is caused by the fact that there is a severe change in the material property sideways the welding line. Within 2-3 mm, in case of laser welding maybe less, there is a gradient of mechanical characteristics of materials. The research work presented in this paper deals with numerical simulation regarding forming of a cylindrical shaped part made from tailored blanks (TWBs), having the welding line situated symmetrical with respect to the part geometry. Due to dissimilar parent materials of the TWBs, it is difficult to anticipate the maximal depth of the formed part. The presented research is trying to determine the maximal depth of the TWBs part based on the maximal depth of the parts obtained from each parent material partly. To simulate the forming process of the cylindrical part the academically version of the Dynaform 5.8.1 software have been used. The obtained results are presented in the final part of this paper work.

Independent dedicated ventilation system is an advanced air conditioning system developed in last few years. There is little research on the design of the system at present. This paper establishes control equation of flow and temperature field based on the energy transmission theory and simulates heat pipe independent dedicated ventilation system using special flow field numerical simulation software. In pretreatment process of FLUENT, this paper uses unstructured six prisms and parallelepiped grid and encrypts grid which makes the result of calculation is more accurate. The simulation uses residual of 10-5 high precision to calculate, and obtains the residual convergence curve. Curve analysis shows that the calculation is very reliable and stable. In post-treatment process, it uses FLUENT results processing module, obtains the temperature flow pattern of heat exchanger independent dedicated ventilation system. We take one of the root canal for analysis. The result shows that the temperature in both sides of the tube is higher, and the temperature through the tube and close to the wall part is lower. It is coincide with the actual working condition of tube ventilation and heat dissipation outside the pipe. This result proves the accuracy of the numerical simulation and provides the reliable theory basis for the design of heat pipe heat exchanger independent dedicated ventilation system.

The present paper is a continuation of a larger study of the authors, which consists of an analysis on the performances of several production systems. In this paper it is analyzed the influences of the method of managing the flows, the method of production programing and the clients demand on performance indicators of a multiproduct assembly line supplied on stock. The assembly line is designed to produce two types of similar products and is made of 5 workstations with mainly manual activities, which are supplied with parts on a stock based method. The performance indicators chosen for analysis were: average work in process, cost per unit, systems reactivity to client demand and throughput. The values of these indicators were obtained by simulating the assembly lines functioning in different experimental conditions, determined of the variation of above mentioned variables, by using ARENA software. The obtained results were interpreted and structured, in a manner to help the process managers to take adequate decisions considering the wanted objectives.

The objective of this paper is to design a linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) controllers for an active anti-roll bar system. The use of an active anti-roll bar will be analysed from two different perspectives in vehicle ride comfort and handling performances. This paper proposed the basic vehicle dynamic modelling with four degree of freedom (DOF) on half car model and are described that show, why and how it is possible to control the handling and ride comfort of the car, with the external forces also control strategies on the front anti-roll bar. By simulation analysis, the design model is validity and the performance under control of linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) controller are achieved. Both two controllers are modeled in MATLAB/SIMULINK environment. It has to be determined which control strategy delivers better performance with respect to roll angle and the roll rate of half vehicle body. The result shows, however, that LQG produced better response compared to a LQR strategy.

According to the relay protection rules, 110kV bus and 220kV bus and above, should be installed special bus protection. This paper do a separate research on bus coupler charging protection from the aspects of bus protection principle and logic of action. It was pointed out that the necessity of blocking differential protection in the process of coupling charging and the new problem of blocking differential protection. This paper puts forward improved bus charging protection after research the processing methods of different relay protection manufacturers, and it improves the reliability of bus coupler charging protection

The paper describes the crack initiation in the layers which were applied by laser surface cladding. The paper investigates the influence of the chemical composition of layer materials and welding technology on the tendency of the crack formation. Proposed method can dramatically reduce the formation of surface cracks in the applied layers.

The use of laser engraving equipment for marking on certain products the expiry date, the bar code as well as customizing them, represents an efficient and non-polluting method. This method is very challenging from the technological point of view and with a lot of process variables that demand research. The current paper tackles the quality of the laser engraved glass in CO2 environment, as a function of the following parameters: the lasers power and the lasers pulse length. Based on the experimental results a quality system is being proposed which relies on the visual examination of the craters, of the top area of the crater and the quantity of excess material surrounding them. The research method used in the current paper is the experiment and the comparative analysis of the experimental results.

Aiming at the demand for timelines, effectiveness and retroactivity in the complex product assembly, this paper puts forward a kind of barcode-based material flow control technology. This technology regards the idea of complete kit as guide which, on one hand, puts forward a closed loop control mechanism including rapidly kitting pallet preparation, field scan confirmation and retrospective statistical distribution service-oriented material flow control. On the other hand, this paper puts forward a material complete kit which forms a complete set technology of assembly planning driven. This paper realized the dispatch of correct material in the correct time and in the correct way. This paper forms a process-oriented material trace statistics technology and solves the classification statistical issues of material status and location. Finally, this paper develops a prototype system and then the effectiveness of the technology was verified.

The existing dynamical systems of wireless capsule endoscopy are studied and analyzed. Based on the shortcomings presented in paper, a novel driving method is proposed. That is driving the wireless capsule endoscopy with three-dimensional orthotropic magnetic field outside the human body, and the resultant magnetic field can be obtained and adjusted through the electric current flowing in three coils orthogonal to each other. This paper focuses on the analysis of complex moving mode of wireless capsule endoscopy, and the result is very important to the design of drive and control circuit.

The paper presents the research results regarding the determination of the calculus relations necessary to simulate the free piston’s movement from the single regime thermo-hydraulic generators. The thermo-hydraulic generator is the main part of the single regime running thermal engines (absolute novelty-pioneer invention), that transforms the thermal energy obtained by burning the fuel (gasoline, diesel fuel, unconventional fuels), in hydrostatic energy. The hydrostatic energy produced by the generator is stored in a hydro-pneumatic accumulator. In the paper are presented the variation functions of the forces acting on the piston in one engine cycle and the variation functions of the kinematic parameters (speeds and accelerations). Because the thermo-hydraulic generator is an absolute novelty, the mathematical model for the piston’s movement developed by the authors is an original one, but is based on classical equations that describe the phenomena that take place in the system.

This paper proposes a convenient and safe method for removing extra matters on overhead lines by distantly irradiating the extra matters with high-energy laser beam. Theoretical study and field experiments on the feasibility of this method were carried out according to the thermal properties of the main components of overhead lines and common extra matters on them. Results show that infrared laser is a better choice to be used to remove the extra matters than ultraviolet and visible laser lights. Experimental results also indicate that there is a large feasible scope of laser power density in which common extra matters can be efficiently removed while the conductors and grounding lines get no harm. Moreover, preliminary design of the laser removing system is given in this paper for practical application.

In the paper analysis of surface topography influence on emissivity of metals was shown. This was performed for infrared band comprising wavelength region of 7.5 13 micrometers. Appropriate characterization and description of object emissivity has a crucial influence on accuracy of IR system for remote temperature measurement, e.g. IR thermography or pyrometry. These properties depend on many factors, including surface topography of material, where especially cavities play a very important role. In references so far emissivity are discussed mainly as influence of type of material (metal, dielectric), its temperature, wavelength or direction of emission. In the paper characterizing emissivity of construction materials in connection with 3D surface topography.

The present paper is part of a larger study of the authors, which consists in the analysis of performances of several production systems. The researches presented in this paper analyze the influence of the method of production flow management, the method of launching in production and the size of demand from the client on several performance indicators of a multiproduct assembly line supplied on stock. The assembly line is multiproduct type (are assembled 2 types of products that resemble as configuration and technology) and it has 5 workstations with mainly manual activities, that are supplied with parts using a synchronous method. The performance indicators considered were: average work in process, cost per unit, systems reactivity to client demand and throughput, their values being obtained by simulating the functioning of the assembly line in different experimental conditions, determined by the variation of the above mentioned parameters, using ARENA software. The synthesis of the results and their interpretation allow the process managers to take adequate decisions depending on targeted objectives.

A very important factor for the hydrostatic guideways is given by the presence of the restrictor on the supply circuit, whose hydraulic resistance may have important effects on the lubricant film behaviour and implicitly, on the static and dynamic stiffness of the system. This paper presents a new method of experimental research regarding the hydrostatic guideway stiffness, depending on the hydraulic resistances values which supply each pocket. During the experiments which approach the influence of the hydraulic resistances values of the restrictors on the hydrostatic guideway stiffness, a centered constant loads of 20, 50 and 100 [daN] was used. The experiments were carried out on an experimental setup composed of an open hydrostatic guideway, having the pocket dimensions of 150x88 [m, supplied with liquid under pressure through means of a pack of adjustable restrictors. The obtained experimental results are presented in both tabular and graphical form and constitute an experimental database which can be used by the machine tools designers and manufacturers. The paper contains recommendations regarding the usage of hydraulic resistances values depending on the machine tool type and size. Also, from the obtained results, recommendations can be made with regard to the type of restrictors to be used, so that the lubricant filtration grade is comprised between admissible values.

In order to optimized the power cable layout design in tunnel, and improved the operation ability of the cable line, this paper analyzed the cable rating and the short-circuit force under different arrangements. 220kV cable circuit was simulated in the tunnel with conditions of the flat and the trefoil arrangements. The temperature and the rating of the 220kV cable under the condition of the two arrangements were calculated in this paper. The short circuit force peak value and its direction of the cable line under short circuit current of 50kA under the condition of the two arrangements were simulated in this paper. The results show that, the cable rating in flat arrangement is better than in trefoil formation. The value and the direction of the short circuit force in tunnel are better in flat arrangement than in trefoil formation. So it is suggested that the flat arrangement is preferred when conditions permit.

A specific problem of the wind turbines refers to the difference between the low rotation speed of the wind turbine rotor and the high rotation speed needed for the electrical generator. Usually, the adaptation between the speed of the turbine rotor and the electrical generator speed is achieved by means of a speed increaser. A recent alternative relates to the use of coaxial counter-rotating wind turbines, which can achieve higher power and improve the conversion efficiency of the wind energy into electrical energy (up to 25%) with a reduced cost of approx. 20-30% compared to similar single rotor turbines. Conceptually, the counter-rotating wind turbine systems can integrate a particular generator wherein the rotor is coupled to a row of blades and the stator with another row of blades, or a commonly generator, coupled to a differential planetary gear, that allows the summation of the blades motions.The paper describes and analyzes kinematic and dynamic aspects of a system consisting of two coaxial counter-rotating turbines and a generator, interconnected by a planetary gear with two inputs (the two turbines) and an output (the generator). The algorithm is based on the property of the differential planetary gear of adding two input motions into one output motion. The kinematic and dynamic parameters of the planetary gear are established in the paper, and a case study is further presented: a small wind turbine equipped with a transmission enabling input speed multiplication.

Imaging quality not only is one of the important criteria for the quality of imaging system, but also is the emphasis of designing a high-quality imaging system. For digital image processing, there are many methods of image restoration for images with noise pollution. The paper tries restoring the fundamental reason making imaging quality degraded, which is image error of lens. While reducing the design requirements of traditional optical system, the paper tries erasing aberration of optical image system, which can achieve good imaging quality.

Firstly, this paper introduces the development of new materials, new technology and new manufacture in power industry of China, energy-saving, low noise and smart distribution transformers are widely used in countryside power grid reconstruction. In this paper, application status and development trend of different types of distribution transformers were introduced and compared in terms of new material and new structure, such as oil-immersed distribution transformer, amorphous core transformer(AMT), dry-type transformer, SF6 insulated distribution transformer, composite transformer and other types of distribution transformers. The development of distribution transformer is mainly based on energy saving, miniaturization, wound core and amorphous alloy nowadays, but the class-H dry-type transformer and tridimensional toroidal-core amorphous alloy transformer are the future direction of development. The technology application of smart distribution grid, power electronics technology and dynamic reactive power compensation technique will also affect the safety and economic operation of distribution transformer.

The purpose of this paper is to present the study of internal structure for investment casting Fused Deposition Modeling (FDM) , and compare it between open and closed ceramic cube . This research aims to introduce a new internal structure for investment casting FDM pattern. With modeling 3D-thermal condition with mechanical finite element analysis on cube ceramic shell open and closed type (during burnout stage) have been computed. As numerical observation the deformation stress for cube square 90° and hollow models with two variants cube open and closed have been evaluated by put the temperature at model. Model was be imposed until 700 °C. Several investigations indicate the probability of better performance for influencing factor drainage ability for each model. However the main scope of the paper is to compare the performance of model during burnout stage ( the deformation on ceramic shell ) . Therefore, a more analytical and practical approach will be good for future research for other mentioned factors. A new generation of internal structure (or a new build style) for investment casting FDM patterns is presented here. The significant reduction of critical loadings on ceramic shell will ensure investment casting foundries for using FDM patterns, which are by square 90° and hollow models.

It is high difficult to control the underwater welding because of the effect of water and the leak proofness of the weld devices which is a troubling problem. In this paper, a DSP-based automatic seam tracking system for underwater welding is designed. This system has the advantages of simple hardware structure, low-cost, rich function software, friendly human-machine interface, and easily realizing. And the work of this paper can be used for further research in underwater welding seam automatic tracking.

This paper investigates the dynamic characteristics of 600MW turbo-generator stator core, including the bending modes, the torsional modes, the elliptical modes, the axial modes and the triangular modes. The magnetic pull formula under the steady-state condition is firstly deduced, based on which the pulsating characters and the core deformation due to the pull excitation are analyzed. Then, the finite element (FE) model of the stator core is set up and imported into ANSYS Workbench to calculate the natural frequencies and the vibration modes. Finally, the calculation is verified via comparing with the experimental data in the published papers. It is shown that the first natural frequency is much larger than the excited working frequency, which means the stator core is in a safe operation condition. The calculation proposed in this paper accords well with the experimental data obtained by other researchers.

This paper relates to a high reliable communication method for the terminal of a networked and distributed power supply system. Terminal refers to the realization of two-way communication between high voltage source of distributed power supply and laden multiple electrical appliances. Due to the characteristics of long distance, complex electromagnetic environment and small amount of communication information between the voltage source and the electrical appliance, this paper designs a new kind of high reliable communication method along with high-voltage transmission, narrow-banded and single-ended synchronous [1,2,8]. Under the condition of satisfying the communication capacity and reliability, this method has been successfully applied to the city network and LED street lamp management system with the advantage of simple circuit design and inexpensive manufacturing cost.

In the paper a lift calculation of a two-dimensional airfoil with a plain flap and Krueger flap is investigated. Numerical-analytical method (NAM) is used to predict the flow field around this combination. In order to calculate the complex velocity in the flow field, the complex variable function theory is employed. NAM based on the joint application of conformal mapping and the discrete vortex method (DVM). The paper presents a brief description of the NAM and some results of the lift calculations of the airfoil with the plain flap and Kruger flap. Comparison of the calculation results with the theoretical data of other authors showed a good agreement.

Basing on the fact that requirements for shift quality in automatic transmissions have been increasing rapidly necessitates the establishment of a suitable shifting control strategy in order to facilitate smoothness of different processes, this paper introduces a simulation model of an 8-speed automatic transmission for front-drive vehicles with respect to detailed shifting strategies and relative parameters. The transmitted torque of the oncoming shift elements before synchronization point can be reduced by an impact function in order to damp the impact and thus make the gear shifting process more smooth. This paper makes a systematic introduction of the structure of 8AT, theoretical basis of control strategy, the establishment of the simulation model and the comparison between test results and simulation results. The conclusion shows that with an accurate dynamic model, simulation results and test results are neighborhood data, the simulation model can be used to help realizing the ultimate goal of better shift quality with higher efficiency, lower shift loads and improved shifting comfort.

This paper studies the attack method in the condition of the torpedo noise covering the target noise with the help of calculation azimuth guidance. To verify the effectiveness of the scheme, the paper does simulation calculation. The simulation results demonstrated that the effect is good and the scheme haves usage value.

The paper introduces the technical features of the railway track inspection cars of different countries and the development review of China’s technology of railway track inspection, and make a brief comparison of the advantage and disadvantage between the chord measurement and Inertial method. The paper also introduce the integrated detection system, which consists of a laser visual detection system, laser radar scanning technology, infrared thermal imaging technology , radar technology and communication detection system. With the implementation of the railway transport, enhanced efforts should be exerted to the comprehensive checking of the track. The development orientation and application of subway inspection equipment is put forward. To develop new portable track inspection cars which can detect the railway tracks and tunnels and the quality of the transmission channel of the train control information, the strength of wireless mobile communication system and track’s electromagnetic environment at the same time.