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Induction motor (IM) is a complex controlled object that is difficult to drive and control. In this paper, direct torque control strategy (DTC) is adopted to drive IM. In order to overcome drawbacks of the bad low speed performance of DTC system, Tornambe control (TC) is used to replace the traditional speed regulator to improve system performance. The results show that TC strategy overcomes the disadvantage of the low speed performance declined and improves the response speed of DTC system, and effectively solves the contradiction between the system response speed and overshoot.

In order to monitor the operating status of the circuit breaker, designed a multi-signal processing system based on the labview. The system acquisite multiple signals synchronous, and combined with MATLAB. Signal feature is extracted with time domain eigenvalues, EEMD decomposition, wavelet decomposition, and finally sent into ELM. The results demonstrate: that the system can achieve the accurate judgment of the operation state of the circuit breaker.

Aim at the disadvantages of traditional circuit breaker mechanical characteristic parameters test. Get the motion pictures of insulation connecting rod through high-speed camera, using the finite difference method to quickly screen out the motion pictures, and selecting punctuation area as a template for learning, using non-uniform sampling have a template matching, obtain the center coordinates of matching results, time interval is known every frame. Through coordinate changes over time we can obtain mechanical parameters of the circuit breaker accurately, fast, conveniently. Lab VIEW programs achieve the above process automatically.

Pulse width modulation (PWM) technology based on rotating coordinate transform is a new type of rectifier control method. Through the electromagnetic transient process of the analysis of the rectifier circuit we can verify the accuracy of this control method. Therefore, this paper first analyzed electromagnetic transient process of the rectifier circuit. By changing the phase and amplitude of voltage to realize the active and reactive power decoupling control independently. Than,it built the simulation model of rectifier circuit with the electromagnetic transient analysis software PSCAD. This cricuit is controlled by PWM based on double closed-loop vector. The simulation and analysis of the circuit are performed on the basis of the model. The simulation results can reflect the electromagnetic transient process of the circuit accurately,so as to verify the correctness of the proposed control method to control the rectifier circuit.

Aimed at the analysis of the ion changes of the North east block in Lamadian oilfield asp flooding field in different period, we puts forward a new and more effective anti-scale agent combined with actual situation on site and the design method of the drug concentration. By combining the extraction liquid ion anti-scale indoor simulation experiment, the changes of different scale anti-scale agent dosing concentration during the period of experience formula. And the north east block in Lamadian oil field, the application of asp flooding experiment, achieved good anti-scaling effect, because of the scale pump inspection cycle to achieve an average of 300 days or more.

According to the gypsum mine goaf disaster formation mechanism and failure characteristics, wireless monitoring system of gypsum mine goaf was designed successfully by using virtual instrument technology, modern sensor technology, wireless transmission technology and the LabVIEW programming language. By using high-precision sensors to acquire dynamical data of monitoring projects, combined with wireless transmission technology to realize the automatic wireless real-time telemetry, using the graphical programming language LabVIEW to develop a software with friendly interface and convenient operation, the monitoring system can timely reflect the dynamic changes of the goaf and forecast the potential safety hazard, to ensure the safety in production of gypsum mine.

Deep foundation pit engineer is characterized with high risk, and it is important to have a study on the risk management of deep foundation pit engineering. Risk Measurement, Risk Assessment and Risk Control of Deep Foundation Pit Engineering is very necessary. There is a need to establish a set of operational foundation pit engineering risk management system to comprehensively and accurately identify and measure the risks of deep foundation pit engineering; and conduct risk control on the basis of risk analysis. Using engineering testing technology, establishes a monitoring based deep foundation pit engineering risk management mode.

The sliding mode control (SMC) design is discussed for a class of time-varying delay systems which is delay-range-dependent and rate-range-dependent. A novel time-varying nonlinear sliding surface is employed. The choice of nonlinear sliding surface is to change the state matrix of sliding mode system, which can combine the advantages of different conventional linear sliding surfaces. Thus the better transient qualities of system states, i.e., quicker response and smaller overshoot, can be achieved. The sufficient conditions ensuring the asymptotic stability of sliding mode are derived in terms of linear matrix inequalities. The algorithms deciding unknown parameters of the nonlinear sliding surface and the corresponding sliding mode controller are also presented. Finally, A numerical example is given to illustrate the effectiveness of the result here.

To fault diagnosis of diesel engine, put forward a fault diagnosis of diesel engine based on EEMD difference energy spectrum of singular value and RBF. Nonstationary original acceleration vibration signal of kinds of diesel engine’s working condition is separated to several IMF and structure a Hankel matrix by the IMF for singular value decomposition, then de-noise and reconstruction one IMF on the basis of the theory of singular value difference spectrum, and use the reconstructed IMF’s energy which include fault information as the income of RBF. This method can judge the kinds of diesel engine’s working condition and fault types accurately in the experiment.

This paper introduces a transformer automatic test system based on virtual instrument (LabVIEW) and PCI hardware platform, and being Improved separately from hardware and software section. use remote control functions to achieve relay testing automatic commutation function and remote automatic control; Increase the voltage and the current automatic locking feature in the empty / load test, and not only improve the security and accuracy of the test system, but also greatly improve the automation of the test system.

Plastic deformation resistance is a basic parameter of mechanics parameters in press work theory and technology. In this paper, the influencing factors of deformation resistance are analyzed and the model of deformation resistance is established. The deformation resistance can be calculated by program with Lagrange interpolation method. This result provides evidence for calculating mechanics parameters and designing metalworking equipment.

Aiming to meet the demand for real-time monitoring and adjustment in modern tailings management process, and solving the problems the development of technological innovations bring about ,this paper comes up with the establishment of this system for tailings based on LabVIEW. Utilizing the LabVIEW software platform, the ACCESS database and SQL language development technology, the paper is able to design various functional modules to optimize monitoring accuracy, data processing efficiency, and costs. The system can play a pivotal role in acquiring real-time change of the indicators, updating and sharing of the relevant data, which can finally assure the operation of tailings.

The management of old goaf is always the emphasis and difficulty in our mining industry. And the filling method is a important means for managing the old goaf. Taking a certain old goaf in ZiBo as an example, the article in detail introduced the process of old goaf management, proposed methods of regulating the quality of filling materials, constructing a new downhole water filter wall and controlling concentration of solution value in 53% to 55%, to strengthen the quality of concentration of solution. Based on this, the strength of filling body is 0.6Mpa more than the designed requirement, which can bring the good experience for similar researches.

Taking the mining subsidence as research object, a real-time monitoring scheme was designed. On this basis, a virtual instrument monitoring system based on LabVIEW was constructed. The data acquisition instrument collect real-time data through monitoring of subsidence and subsidence slope deformation by this system in range of mining influence, then control and transform it. After this, the data was transmitted to the computer terminal through wireless transmission equipment, and monitoring will be got after analysis and prediction by computer terminal. This result can provide mining of this area with real-time advice and guidance, to reduce the harms brought by mining subsidence and unnecessary economic losses.

This paper approaches the rules of curvature mode and curvature mode difference about a simply supported beam. On the basis of the theory of curvature mode, through numerical simulation analysis of simply supported beam on four conditions, the result of simply supported beam with curvature mode and curvature mode difference were obtained. The results show that for the damaged beam information with numerical simulation, the curvature mode and curvature mode difference index calculated by difference method at the unit length unevenly is with strong noise, which can even submerge the beam damage information, and for different damage index of the beam, damage information from curvature mode difference curve is stronger and effected by unit length weaker than those from curvature mode curve, and damage information from curvature mode curve and curvature mode difference curve decrease with the increasing mode order.

Large Eddy Simulation (LES) based on the least square meshless method was proposed in the present paper to simulate the classical turbulent flow around a stationary 2D circular cylinder. The subgrid scale model of Smagorinsky-Lily was employed to close the Navier-Stokes equations filtered by Favre filter. The Reynolds number is 3900 which means that the flow is subcritical and the wake is fully turbulent but the cylinder boundary is still laminar. Results obtained in this paper were evaluated by comparison with published experimental results and other numerical results. The results obtained in the present work show better agreement with the experimental values than other two-dimensional LES results .

Using modal analysis to train and bridges and piers for dynamics analysis, we got a theoretical solution. Using wireless sensor network architecture monitoring system for Bridges and piers of the acceleration and the settlement monitoring, in considering static load loading situation, through contrast train before and after the settlement of piers the quantity change and Bridges and piers acceleration size, draw piers vertical stiffness of the bridge vibration impact is not significant. Study of the bridge piers and transverse vibration characteristics, it is concluded that the piers lateral stiffness is far less than that of the vertical stiffness, piers and bridges in transverse have larger dynamic response to produce.

Curved girder bridge can adapt to the complex needs of road, so it applies more and more. Because prestressed curved girder bridge is spatial structure, its deformation under load, prestress etc is very complicated. If ill-considered, it will cause accidents as cracking of beam body, too large transverse displacement and bearing disengaging etc. In this paper, by analysis of engineering examples, using ANSYS finite element analysis software modeling and calculating, we get the deformation law of small and medium span curved girder bridge under deadweight and prestress, and the law has guiding significance and practical value on design.

This paper takes Nanhu project of Tangshan City under the soil condition of foundation pit excavation as an example. A model is established to research on the mechanical behavior effect of around composite foundation of CFG under soil lateral displacement by using ANSYS finite element software. The model analyzes the distribution law of horizontal displacement, stress of pile, soil between piles of CFG composite foundation under soil lateral displacement. Put forward a calculation formula of pile displacement by considering excavation depth, excavation distance.

This paper presents an automatic inspection robot for insulators installed on 500kV power transmission lines. In order to detect the poor insulators automatically, the robot’s behaviors are analyzed, and a behavior control model based on Finite State Machine (FSM) is established. Moreover, an exception handling method is proposed based on sensors and timers. The results of experiments in the laboratory prove that the control methods mentioned above are correct and valid. Experiments on a 500kV transmission live line show that the inspection robot can not only automatically move along the double insulator strings with variable intervals, but also reliably handle the abnormal conditions including slipping, power shortage, deadlocking, sensor abnormity, and probe loosening.

Tianjin biomass energy utilization situation is surveyed and the result shows there have five kinds of use pattern in Tianjin biomass energy utilization: household biogas, livestock and poultry farm biogas project, straw biogas project for centralized supply, straw gasification for centralized supply, and biomass thermal utilization. Then the using scale, advantages and problems of these five kinds of use pattern are described. Finally, this paper analyzes the biomass energy utilization strategy in Tianjin, respectively from the perspective of biomass project construction and management, energy comprehensive utilization, new countryside planning and construction.

Room-and-pillar mining method plays a dominant role in gypsum mines, which owns a low resource recovery ratio and has left many gobs leading a series of safety production problems to mining enterprises. To get an utmost resource recovery and avoid gob collapse, a secondary utilization scheme has been made by feasibility analysis and theoretical calculation. In this scheme, theoretical calculation about the occurrence conditions of mining damage has been done, and the deep research direction of the mining damage mechanism in gob-effect gypsum mines has been pointed out. This research and its train of thought could provide the gob-effect gypsum mines with reference that would increase ore recovery ratio and prevent mining damage.

For the multi-channel data acquisition system, crosstalk significantly affects the sample accuracy. Through analyzing the mode of multiplexer and the sampling timing sequence, we demonstrated that crosstalk effect mainly results from the switch of multiplexer for the low- frequency multi-channel data acquisition system. A new crosstalk testing method based on phase-shift rectangular waveform for the multi-channel data acquisition system was proposed. The phase-shift rectangular waveform was designed. Experiments were conducted to test crosstalk effect of the multi-channel data acquisition system. The experimental results were demonstrated that the proposed approach based on the phase-shift rectangular waveform exhibits a distinct feature in effective channel crosstalk testing, compared with waveforms of other types. Thus, the proposed method is effective to detect crosstalk of the multi-channel data acquisition system.

Turbocharger is an effective technique to achieve higher thermal efficiency reduced emissions. And hybrid turbocharger is proven to be a promising technique to eliminate the well-known 'turbo-lag' effect of the turbocharger. In this paper, a global optimization of hybrid turbocharger technique with variable geometry turbine and exhaust gas recirculation was carried out. The diesel engine was modeled by GT-SUITE software, which is a 1D simulation environment. Moreover, a dynamic programming based optimizer, which was developed in Simulink, was integrated with the diesel engine model. Simulations results show that the optimized parameters can improve the engine fuel economy significantly under Chinese typical urban driving cycle.

Shock and vibration response is a particularly important signal to characterize the system state. This paper analyzes the reason of fault generated high speed machine, vibration response mechanism and its frequency characteristic. According to the measured vibration signals, done time and frequency domain features analysis, wavelet packet analysis and frequency domain energy analysis, put forward a kind of fault comprehensive diagnosis method with accurate and rapid identification characteristics, can adapt to the complex vibration response signal with interference and low signal to noise ratio.

Based on the theory of ANN (Artificial Neural Network),The paper raised the method of construction control, and introduced the common forecasting method. According to the characteristic of ANN itself and the complexity of factors which influence the elevation, the paper analysed the influence aspects of ANN. On the promise of bridge construction precision, the paper raised section measure、elasticity model、temperature、delay of construction and cantilever for neural network’s input vector in bridge construction process. With the help of Graphical User Interface, built ANN, made the forecast function in the bridge construction into reality. Introduce the theory of Artificial Neural Network(ANN) into long span prestressed concrete continuous rigid-frame bridge construction control.

A new topology of shunt active power filter with two-leg three-level clamped capacitor in the main circuit is presented, and the operation principle and control scheme are introduced. The adopted device is operated as a controllable current source to eliminate current harmonics. The new hysteretic current comparison control scheme is used to track the command current and to balance the neutral-point voltage. Meanwhile the redundant operating states in the adopted inverter can be selected to compensate the clamped capacitor voltage to achieve the dynamic balance of the capacity voltage. Simulation results show that the shunt active power filter can effectively eliminate harmonics of the nonlinear loads.

With the changes of learning psychology and information technology, CSCL tools should also keep up with the times and meet the growing needs of learners. The appearance of RIA can make up the deficiencies of Web-based CSCL tools at present. With the use of RIA, the next generation tools could be realized with high interactivity and richer user interfaces. Silverlight is one of mainstream technologies of RIA, and it has the advantages of better user interfaces, high development efficiency, newer way of communication, and so on, which other RIA technologies could not reach. In order to facilitate collaborative knowledge construction of learners, the paper design and develop a Web-based CSCL tool which has the function of real-time interactivity with words or graphics.

Work out control measures for pillar upward mining of left-over coal, in view of coal floor movement, this paper analyzes theoretical foundation and mechanical properties of mechanical model on coal floor movement of rock strata between coal seams in pillar upward mining of left-over coal and presents a simplified corresponding mechanical condition. Taking into the relation between layer movement and time consideration, the PTh model is used to show its rheological properties. By using a two-dimension model, mechanical model of coal floor movement is set up and both ends of cantilever beam are fixed. Finally, subsiding partial differential equation is induced at different districts in pillar upward mining of left-over coal. After solving the equation, prediction model about law of coal floor movement at different districts is gotten in pillar upward mining of left-over coal, which provides a theory basis for further study on upward mining.

The damage of the printed wring assembly (PWA) was treated as one of the main factors of the failure of electronic equipment. Thus the PWA must be studied and investigated. As the important prerequisite of the study, the dynamic characteristics of the PWA were determined in this paper. Here the dynamic characteristics of the PWA were modeled and analyzed by finite element analysis (FEA) method firstly, and then the experimental modal analysis (EMA) method was also used to study the dynamic characteristics of the PWA. The results obtained from above two methods were compared with each other, and good correlation was shown. So the correctness and accuracy of the FEA model was verified. On the base of that, the Z-axis (the normal of the board) of the PWA was determined as the main direction to be excited; subsequently the main modes in that direction were also determined. Furthermore the principle described as the components crossed by bend lines are detrimental to solder joint survival was used to prognosticate the packages which may be damaged.

In the research of CSCL (Computer Supported Collaborative Learning), interaction behavior analysis is an important part. In order to effectively analyze the learning interaction and find ways to promote collarative learning, it is necessary to establish a classified framework on micro-level for interaction behavior. This paper proposed the concept of micro-interaction firstly, then in view of text-based interaction is still the most important form of interaction, establishment of classification framework for the micro-interaction lauguage behavior. This article also describes the determination of the classification framework and development process, and finally discusses the value of its in CSCL system through an example．

To prevent and control fire and explosion disasters, the premixed methane-air explosion was performed under restricted condition. In the experiment, the high speed schlieren photography system was used to record the flame characteristics and propagation mechanism. At the same time the ion current probe was used to reveal the inner flame structure characteristics. Based on the images of High Speed Schlieren Photography, the flame acceleration and flame structure were discussed in detail. In addition, the flow field characteristic of explosion flame was disclosed clearly. The microscopic evolving process of laminar-turbulent transition was accomplished in the period of flame structure change. As an alternative observation and detect technique, the high speed schlieren photograph system was used to capture flame front microstructure dynamic process precisely. Based on burning chemical and explosive dynamics, the optical measure method can record flame dynamic behavior visually, which further helps to disclose flame microstructure characteristic and the inner dynamic mechanism.

Fast multipole boundary element method (FM-BEM) is applied in three-dimensional elastic contact problem, but the singular integral influence calculation efficient. How to solve singular integral is become an important problem for improving FM-BEM. In this paper, Taylor series expansion and Laplace transformation were introduced; it can be used to improve the singular integral. After Laplace transformation, the singular integral is written as exponential series form, which can be suit for fast multipole method. It is not only solving singularity, but also suit fast calculation. This method improves the calculation time and calculation accurate of FM-BEM.