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Experimental data reveal that dry filters utilizing filter papers tend to change their operational characteristics whilst in service. When the airflow stream in the filter is constant, the pressure losses, and hence energy losses, will increase. On the other hand, when a constant pressure head is maintained to induce the flow, the flow rate of the flowing medium will decrease. A possible solution is a filter made from several filtering layers, their density varying along the dusted air flow path. Basing on the theory of filtration, the density of filter layers shall be chosen such that the amount of particulate matter settling on individual filter layers should be identical. The paper summaries the results of experimental testing of five-layered filters. Of particular interest is the distribution of collected dust mass along the airflow path in the filter in relation to the layer density.

In poor coverage area of high-speed railway, the frequent handoff will increase the dropped-call rate. An approach to improving the quality of wireless communication is adding a relay between two base stations. Paper is about analyzing the dropped-call caused by handoff in this scene. This paper proposed a model for dropped-call probability through analyzing the handoff probability, same frequency interference and ping-pong handoff. Based on the simulation and comparison of the dropped-call model, we found that putting a relay between the base stations can significantly improve the dropped-call problem, and the peek rate of dropped-call decreased by an order of magnitude.

Golf has become an increasingly popular sport. Determination of motion parameters of golfball can give quantitative suggestion for players. This paper introduces the principles of determinationbased on Doppler radar. The parameters of golf motion to be measured include velocity, angle, spinangular velocity and position. A golf realtime tracking system is designed with one transmitting antennaand three receiving antennas in this paper. Simulations validate the feasibility and high accuracyof this system. This system makes referential significance for golf realtime tracking system.

Critical clearing time is to determine the time point of the collapse of the power system when the power system occur transient stability by a huge of failure. So that the one is an important data on protection system in power system. Therefore as an electrical engineer must to look on mostly the point of one to analyze and design in the power. In this paper, through the protection relay and breaker analysis of operation to know the team of protection relay how to complete the automatic monitoring and isolated the fault-equipment in power system. To study and analyze the swing equation and equal area criterion, we found out the relation of critical clearing time is changed with power factor and frequency. The critical clearing time was verified a non-constant value which is changed with the power factor and; if the load power factor is high, the critical clearing time is high but the frequency is high, the critical clearing time is low with system swing in the transient stability. This paper will be verify below each paragraph.

The low conductivity material such as cancellous bone, cortical bone tissue and soft tissue is the mainly content in the spine. And the improvements on distinguishing the low conductivity material can make a contribution to the spinal fixation surgery process, and protect the patient from spine incident trauma injury during internal fixation prosthetics with implanting pedicle screws. As a result the low conductivity material detection is of great importance in biomedicine study. According to the magnetic property difference of different low conductivity material, an eddy current detection method based on GMR sensor which is proposed in this paper. Compared with coil sensor in traditional non-contact detecting system, GMR sensors have advantages of higher sensitivity, higher precision, better linearity and better stability. Based on this methods, this paper introduces a low conductivity material detection probe. Several experiments indicate that this detection method can detect the low conductivity material NaCl solution with conductivity of 0.128 S/m, whose electrical conductivity matches that of biological tissue. This results lay a solid foundation on the biological tissue detection research.

With the rapid development of information technology and deeply evolution of air-to-ground combat mode, the combat between air targets and netted radar will be an important component of future warfare. Design and development of netted radar training system is historically inevitable. This paper aims to design and develop networking radar training simulator system. We have studied and designed the system structure and function. With deeply analysis of the key model of the system, the training simulator was implemented by object-oriented technology. This paper mainly introduces the overall design of netted radar training simulator and the simulation method to realize the key models.

In this paper, a new method using wavelet packet energy spectrum to identify transformer inrush and internal fault current was proposed. Wavelet packet transform respectively decomposed inrush and fault current, then calculated the energy of each frequency band of decomposed signal. Finally, the conclusion showed that the energy of internal fault in high frequency band is much less than that of inrush. The difference was quantified and it could be observed intuitively. Through extensive simulations, this paper proves that the method in terms of identifying transformer inrush is accurate and effective.

In this paper ,the method of the fluorescence lifetime (FL) in fluorescence optical fiber temperature sensor is used to measure the temperature. During the fluorescence information processing , because of existence of the system noise interference, measurement reliability of fluorescence lifetime has been greatly affected, thereby reducing the temperature measurement precision. This paper presents an improved wavelet threshold de-noising method to signal processing, which improves the signal-to-noise ratio and increases the measurement of fluorescence lifetime precision, reduce the error of temperature measurements at the same time. The experimental results demonstrate that this method is effective.

This paper describes the construction of remote online access to PLC Laboratory based on Internet .The Laboratory apply industrial communication modules, relay on the powerful ommunications capabilities of Siemens PLC , transfer data by the Internet. The PLC of the Laboratory can be accessed by remote PC. The remote PC possible upload and download PLC program, online diagnosis, online monitoring, etc; and directly observed action of PLC by video, determine equipment movement is whether correct or error. The paper introduces the network topology, various functions and data security communication method of the system.

Robotic remote operation has become a new research hotspot in many fields, experiments on remote operated manipulator doing surgeries for the patients have been carried out in medical science. This paper takes the manipulator of four degrees of freedom capturing the target object as the study background and comes up with a new method of remote control for a robotic arm based on an electromagnetic tracking system which serves as the signal acquisition device. Thus the arm movement can be the input of the robot arm control loop and guides the motion of the robot arm. Firstly, the paper builds the kinematics model of the experimental robotic arm. Secondly, based on the analysis of human arm structure, the paper proposes an appropriate experimental program. Finally, experiments on remote operation have been carried out, the results of which prove the effectiveness of the method above.

Steady-state magnetic field superconducting magnet power adopted double-inverse-star thyristor rectifier solutions, it is a typical non-linear load which will bring great reactive power impact and harmonic pollution at runtime. In this paper, according to the scheme of scientific facility chain-type high voltage active power filter (APF), a three-grade voltage balance control of capacitor method was proposed. Considering the non-linear characteristics of APF, we using fractional order PI controller instead of ordinary PI controller. The solution of fractional order calculus is realized based on the improved Oustaloup algorithm. Finally, the working effect of fractional order PI controller and ordinary PI controller are comparative analysis through simulation and experimental results, the results show that the DC voltage balance control strategy used in this paper is correct, and has a certain reference value.

With the development of mobile communication, D2D (Device-to-Device technology) has become a research hotpot. In this paper, we first derive the channel capacity of an n-hop link and get the formula of spectrum efficiency. And then to maximize the spectrum efficiency, we focus the algorithm of selecting the best relay for data transmission in a D2D cluster of cellular network. The algorithm proposed in this paper is an improvement of the greedy algorithm. This algorithm solves the problem that the greedy algorithm would be invalid in the case of having a big hole in the topology. At last, we could see a significant gain in terms of spectrum efficiency by using the new relay selection algorithm.

The topic of this paper is the short review of current state-of-the-art in the field of material models of concrete and its utilization for numerical analysis of concrete and prestressed concrete structures. The problem of compiling constitutive relations for numerical simulation of concrete structures is not yet closed. It is caused by different behavior of concrete in tension and compression. Due to formation and development of cracks it is necessary to describe material model of concrete in tension as precisely as possible. The paper aims to create a brief historical overview in this field and then aims to create a short summary of current approaches that were published in conference contributions and in journals during recent years.

This paper presents an experimental investigation of heated tool welding of polypropylene matrix composite. The goals of this paper are to investigate the issues of local changes of welding strength that depends on heating time. For experimental procedure, specimens were injection molded as ISO tensile test specimens and matrix was reinforced by organic and inorganic materials. In addition, welding of specimens was carried out by non-contact heated tool butt welding process. Within the range of the weld process parameters were investigated, the highest weld strength dependent on heating time was achieved of the order of 94% to the base strength of the material. And then these specimen’s maximum welding strengths and energy at break point properties that were depend on heating time have been compared.

This paper briefly recommends the conception and syntax construction of the expert system language – CLIPS. Aim at fault happening mode, the paper build up fault analysis model of certain self-propelled gun servo system with CLIPS, compiled knowledge base and reasoning engine, realized embedded programming of CLIPS, and illuminated the application of CLIPS in fault diagnosis of self-propelled gun servo system.

This paper carries on the simulation and optimization of hydraulic system, which focuses on the high energy consumption problem of large-scale blow molding machines. According to the characteristics of long work period and great fluctuation of flow demand, the paper designs the oil supplying system that can match the actuators’ hydraulic energy demand, introduces the working process of each component in the system, and analyzes the key technology of hydraulic system as well. The design and research avoids the shortcomings such as more components, complex debugging, discontinuous control and unstable operation, substantially reduces the installed capacity of variable pump and driving motor, and in the meantime, solves the impact problem of actuators effectively, which can make hydraulic system high efficiency, energy saving and run steadily.

At present, digital printing technology develops rapidly, but in terms of color reproduction, digital proofing and the traditional mechanical proofing are different, it’s difficult to determine the color reduction according to the dot size, mainly manifested in the difference between the display color and the actual digital output color. In this paper, through analyzing the differences with color management technology, to keep consistency between the original display color and digital proof color as the goal. Through the study, mainly provides solutions for color consistency of digital proofing for paper packing.

Aiming at the relatively complicated methods of zero-line detection of artillery, and the limiting of high requirements for target range measurement or the field of calibrating artillery of combat troops, this paper presents the method that laser alignment is applied to complete zero-line detection of artillery. This paper introduces the basic principles and methods of the method, and conduct theoretical analysis, modeling and calculation and determination of related parameters based on the optical principles of laser. This method can be used to complete zero-line detection of artillery in small venue, and provide convenient conditions for the detection for aiming line of artillery, the method is especially suitable for limiting of the field of calibrating artillery of combat troops, and calibrating artillery before shooting in a relatively harsh climatic conditions.

This paper proposes a stator flux estimation method for induction motor based on Prescribed Convergence Law algorithm. A stator flux observer is designed and applied for direct torque control (DTC) of induction motor. The observer tracks stator current and its differential with Prescribed Convergence Law algorithm of second order sliding mode in order to estimate rotor flux, and then estimate stator flux using the relationship between stator flux and rotor flux. This paper takes the differential of estimated flux error as disturbance and divides the MIMO (Multiple Input Multiple Output) observer model into two separate SISO (single input single output) systems, which simplifies the stability analysis. The observer is applied to DTC of induction motor and achieves a good control effect. Simulation experiment results validate the proposed method.

Based on the State Grid Unified Application Platform as the carrier, this paper proposed an extensible access control policy. For a long time, the combination of electric power enterprise internal environment and traditional access control are very inadequate. The traditional access control model on the current unified platform access and control permissions interaction problems is almost blank. Therefore, this paper puts forward an improved access control model. The model has solves some key problems of access control in State Grid Unified Application Platform , such as specific role division, interaction between roles, permissions delivery, senior role inherited permissions unlimited scale-up, and permissions linkage.

A control strategy and implement method for the no-load cutting-in of double-fed induction generator in power system are introduced. The paper analyze the basal principle of DFIG under no-load condition, and build the correspondent mathematical model. Then according to the model, the paper propose a control strategy on the basis of magnetic flux linkage vector orientation control. Using simulation software set up a simulation model. The result of simulation showed that: the no-load grid connection control strategy can effectively keep the stator voltage track the time-varing grid voltage. At the interconnection instant, the impulse current is almost zero, thus the soft cutting-in of DFIG is well realized.

The paper deals with the improvement of quality control system harmonic drive with servo applying the method of compensation torque oscillations. The method consists of applying the rejection block. Post documents the oscillatory nature of the system servo-harmonic transmission. Described the reduction block connected to this system suppresses the oscillation of torque, speed and position of the harmonic drive output shaft thereby improving the quality of the regulatory process.The papers solves the problem of torque oscillations of the system which consist of servomotor and harmonic drive. Described rejection filter connected to the input of the system damps oscillations and increases the quality of control.

Recently, Multi-bit flip-flop usage has shown its advantage in dynamic power saving in nowadays commercial electronic design. This paper present a more comprehensive comparison of chip-level synthesis result by using single-bit flip-flop and multi-bit flip-flop standard cell and except for analyzing the power and area benefit from replacement under the maximum speed, this paper give a compromise solution to solve that using multi-bit flip-flop cannot run as the fastest as single-bit with even large area. The trade-off between a multi-bit flip-flop cell driving strength and its area when designing multi-bit standard cell that will greatly influence synthesis result as speed arise are also mentioned. Finally, this research about MBFF further usage improvements may be helpful for designers to know how to take full advantage of multi-bit flip-flops to bring about the wanted benefit.

In the view of the traditional purely mechanical regulator’s disadvantage, this paper proposed a new type intelligent gas pressure regulator. Its advantage is the ability to achieve accurate output pressure, remote control and centralized management. It can resist the disturbance of inlet pressure and flow rate changes. In this paper, we introduce the regulator’s structure, working principle, mathematics model and simulation model. According to the simulation result, it can basically meet the working demand.

Sliding mode control systems provide robust and simple means for controlling linear and nonlinear plants whose parameters may vary within known boundaries. The existence of an ideal sliding mode requires fast switching, which induces chattering in the system, may excite high frequency plant dynamics and consequently affect the stability of the system. This paper proposes a new simple sliding mode controller based on second order reachability law. The reachability condition in this paper is based not only on the first derivative of the switching function but also on its second derivative. The proposed controller alleviates chattering, guarantees zero steady state error, and offers smooth transients for the system states. To demonstrate the validity of the proposed controller, a second order system is used as a workbench example. The simulation results of the workbench example using MATLAB illustrate the feasibility and efficacy of the proposed controller.

As a new type of vertical take-off and landing unmanned aerial vehicles, four-rotor unmanned aircraft has strong load capacity, simple structure, flexible operation Characteristics, so it is the preferred method of execution the air, and is widely used in military and civil field. Based on four-rotor aircraft structure and movement theory, this paper designs the aircaft control system based on ARM. Based on upper machine, the design of PID control algorithm was tested in this paper. From the results, the stability of the controller is good, and its speed control is superior to the single closed-loop.

Bridge health monitoring has become an important means of transportation for bridge management, and the bridge strain is an important health detection index of bridge. In order to simplify the wiring complexity of test site, this paper aims to research a wireless bridge strain acquisition system based on Wheatstone bridge. The instrument can realize accurate acquisition of bridge strain data, then collects and transmits data remotely to the monitoring data processing system of PC through WIFI. This paper will make a detailed introduction of the system through two aspects of hardware and software.

This paper brings forward a new DFS algorithm in the unmanned aerial vehicle (UAV) platform communications relay system and gives the disposition processing. As a material application example, the paper simulates the algorithm. Compared to other algorithm, the result of simulation indicates that the new algorithm has these characteristics such as fast finding interference and steady changing frequency. The algorithm can satisfy request of system in complex communications environment and ensure Quality of Service (QoS) of system.

This paper analyzes the micro-mechanism of interaction between femtosecond laser and one dimension material. It gets the figure of temperature change with time by calculating the Two Temperature Equation(TTE) in the process of the laser ablation. And it presents the surface characters of metal material. Additionally, the plasma is generated when the temperature of ion subsystem is far higher than the melting point of copper metal. The paper can give the laser ablation threshold by the numerical calculation. It will help the researchers ensuring the laser fluence for preparing the copper film better.

Aiming at problems of lack of theoretical research and existing resources, etc., in equipment’s combat resilience design for the chinese military, a new kind of equipment’s combat resilience design theory-TRIZ contradiction maters are used to describe the technical conflict in practical problem, the conflict resolving matrix is used to analysis problem, and the principle to solve the contradiction is given at last. This theory is strongly to solve the contradiction problem. For these reasons, the equipment’s combat resilience design process is proposed in this paper, and then taking the battlefield maintenance of radar phased array antenna as an example, this paper analyses the improvement design method to introduce the design of phased array antenna by using the TRIZ conflict matrix. The results show that, TRIZ conflict matrix can effectively guide the equipment’s combat resilience design, and can indicate the direction for the equipment’s combat resilience design to improve design efficiency.

In the absence of cooling measures, the chip temperature of high power LED rises rapidly. When the junction temperature exceeds the maximum allowable temperature, the high power LED will be damaged due to overheating. In the design of high power LED lamps, the main work is to the temperature design. Using a good linear relationship characteristic of the semiconductor devices between the LED junction voltage and junction temperature, this paper measured the high-power LED working voltage, working current, temperature of the incubator and heat sink. Adopting the method of electrical parameters, the paper measure the temperature resistor of high power LED. The high-power LED temperature resistance measuring instrument is designed and made. The temperature resistance from the LED wafer to the heat sink is measured fast and accurately, and the error is less than 5%.

In laser induced thermal crack propagation (LITP) cutting brittle materials, according to the laser absorption ability, materials are divided into the body absorption and surface absorption. This paper indicates the fracture mechanism of LITP cutting surface absorption brittle materials. The crack extension appears in the lower surface firstly in this stress distribution state, then the crack extends to the upper surface and the laser scanning direction with the LITP cutting. The stress field of cutting ZrO2 ceramic is studied by finite element software ANSYS. The crack propagation process of cutting silicon wafer is studied by finite element software ABAQUS. According to the fracture mechanism, the curve cutting the ZrO2 ceramic experiments and the cooling lower surface cutting the silicon wafer experiments are carried out in this paper. Optical microscope and laser scan confocal microscope (LSCM) photographs of the curve path the ZrO2 ceramic and separation surface cutting the silicon wafer are obtained to examine the cutting quality. The quality of the curve path is very good. The quality of the separation surface in cutting the silicon wafer with the cooling lower surface is better than conventional environment.

Pipe fracture and compensator tear may happen when directly buried pipes with large diameter, high temperature and pressure adopt preheated installation. Combined with engineering, this paper analyzes theoretically the fracture accident on DN1200 return water pipe during the period of cold operation and analyzes various factors which cause the pipeline fracture, when adopt open ditch electric preheating. By the numerical simulation, the size of influence factors on fracture was obtained, and the conclusion that the tensile stress is greater than the compressive stress was also obtained, where the preheating temperature was defined by means of “intercycle temperature”. It is worth nothing, the buried pipeline will emerge vertical bending under the main impact of soil and transportation loads. The vertical bending is related to pipe base, and the value of curving stress will be very big if the pipe base is mishandled. The coupling effect of curving stress and the temperature tensile stress can lead the pipeline to fracture, such as the disposable compensator place, the pipeline welding place, corners, the pipe wall flaw place and so on. This paper proposed the effective preventive measure which may reduce the occurrence probability of pipeline fracture during temperature drop process.

The following paper proposes a new system based on the direct transformation of a small-size jet engine thrust into torque. The paper determines the performance indices both of the design of the system transforming the jet thrust into rotary motion and the power generation.

This paper studies the different calcination temperature on the properties of titanium gypsum physical effects, and the mechanism of the effects are discussed in this paper. Research has shown that with the increase of calcination temperature, the mechanical properties of titanium gypsum present a trend of after rising first down. When the calcination temperature is 180 °C, titanium gypsum calcined product mainly for the half water gypsum phase, the mechanical strength of samples of titanium gypsum achieve maximum at this time, The mechanical properties of titanium gypsum samples: 2h flexural strength was 0.94MPa, 2h compressive strength was 1.87MPa, absolutely dry flexural strength was 1.54 MPa and absolutely dry compressive strength was 2.52 MPa.

Aiming at the radar vertical detection coverage limitation given by manufacturing factories, this paper put forwards a new characterization method of radar’s air surveillance coverage: it is the projection distance of furthest detection point for different RCS targets at different altitudes, which can directly show radar’s quick response to the attack action launched by fighter. Then this paper gives the calculating method of coverage characterization method, and calculates radar detection coverage of typical medium-low altitude search. The result shows that the detection ability to penetration fighter is weak for high altitude and below 300m altitude, especially for the high altitude penetration stealth fighter.

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.

Carbon dioxide CO2could corrode the oil well cement paste matrix under agreeable moisture and pressure condition in deep oil wells, which could decrease the compressive strength and damage the annular seal reliability of cement paste matrix. The problem of oil well cement paste matrix corrosion by CO2was researched in the paper for obtain the feasible corrosion prevention technical measures. The microstructure and compressive strength of corroded cement paste matrix were examined by scanning electron microscopeSEMand strength test instrument etc. under different corrosion conditions. The mechanism and effect law of corrosion on oil well cement paste matrix by CO2were analyzed. And the suitable method to protect CO2corrosion in deep oil wells was explored. The results show that the corrosion mechanism of cement paste matrix by CO2was that the wetting phase CO2could generate chemical reaction with original hydration products produced from cement hydration, which CaCO3were developed and the original composition and microstructure of cement paste matrix were destroyed. The compressive strength of corrosion cement paste matrix always was lower than that of un-corrosion cement paste matrix. The compressive strength of corrosion cement paste matrix decreased with increase of curing temperature and differential pressure. The corroded degree of cement paste matrix was intimately related with the compositions of cement slurry. Developing and design anti-corrosive cement slurry should base on effectively improving the compact degree and original strength of cement paste matrix. The compounding additive R designed in the paper could effectively improve the anti-corrosive ability of cement slurry.

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.

JG590 steel is one of high strength, low alloy and high toughness engineering machinery steels, and its tensile strength is not less than 590MPa. The fatigue failure is one of the main forms of the welding structure failure. This paper studies the influence of the ultrasonic treatment on welded joint fatigue performance. Through the experiments, the paper compares the fatigue performance on as-welded welding joint with the performance on ultrasonic impact treatment welding joint. The results show that the ultrasonic treatment reduces the stress concentration factor by improving the geometry of the toe of weld’ area. It transforms the welding residual tensile stress on the surface of the welded joint into compressive stress, and makes the surface of the toe of weld’ area hardening. The fatigue strength of welded joint is increased by 114%, and the fatigue life increased by 133~184 times.

This paper welds a layer of austenitic stainless steel (SS316L) on specimen of low carbon steel (C15) with a cylindrical surface using MIG Technology in the experiment. The sample was upsetting experiment, cracks and material forming observation respectively using embossing punch, no lubrication flat punch and lubrication flat punch under the condition of 750 °C, 900 °C and 1050 °C. The paper research on forming mechanism of the specimen under laboratory conditions based on the experimental results, the axial symmetry theory model and Numerical Simulation.