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The mechanism of cable crosstalk involving what and how does the factors affect the level of crosstalk is introduced in detail. A transmission line model for predicting crosstalk between power cable and the other wires nearby with common reference ground based on multiconductor transmission theory (MTL) is developed. Crosstalk among circuit configurations when the victim cables with load terminations are different types is analyzed and simulated. Models where the types of the victim lines are shielded coaxial cable, shielded twisted pair and unshielded twisted pair are simulated. It is found that the shielding can provide an attenuation of about 50dB than the unshielded cables. In addition, the condition of multi-cable coupling is simulated and some thoughts are brought out to inspire more detailed study. Finally, some measures are suggested to suppress the crosstalk between cables according to the two-type of coupling mechanism (inductive coupling and capacitive coupling).

By examining the compressive and flexural strength of composite and using scanning electron microscopy (SEM), we analyzed the influence of sodium hydroxide on the properties of FGD gypsum and slag composite materials and discussed the influence of sodium hydroxide on the setting time and mechanical strength of the composite materials and presented the action mechanism of sodium hydroxide as a stimulator. The results show that when the content of sodium hydroxide was percent of 0.25, the maximal strength of FGD gypsum-slag composite materials was reached.

When larger scale of small hydropower and wind power exist in power system, the traditional reserve capacity algorithm is no longer applicable at the same time of reducing the carbon emission. Aiming at the volatility and non-regulatory of small hydropower and wind power, considering the forecast error of small hydropower, wind power and load,the unit outage rate and other factors, combined with the actual operation parameters of one regional power system in Southwest of China, the wind-hydro – thermal power coordinated operation of multiple objective function optimization calculation model of reserve capacity is established. Using the weighted coefficient method of unified objective method, it transforms the multi-objective optimization problem into a single objective optimization one. Applying the exterior penalty function method, the constrained optimization problem is changed into a non-constrained optimization one. The improved particle swarm optimization algorithm is got by introducing the particle concentration cognition into traditional particle swarm optimization algorithm. The simulation results verify the validity of the model. To Compare them under different strategies, this method can get less fuel expenses of thermal power units in the case of lower loss of load probability (LOLP).With the small hydropower and wind power output size to optimize the spinning reserve capacity. The model and the algorithm are helpful for drawing up optimization strategies of the reserve capacity in those regions in which larger scale small hydropower and wind power exists.

As the development of the slurry pipeline transportation system complexity and intelligent,it is more difficult to establish the reliability of the system.This pape take advantage of the descriptions of dynamic systems of stochastic failure petri net,applying in the field of slurry pipeline transport system reliability analysis.At same time,with the combination of Markov theory, it established the model of the hydraulic system reliability analysis.The feasibility and availability of the method is proved through an example of hydraulic system of slurry pipeline transportation.

This paper begins with analyzing the hazard of system harmonics and proposing the effectiveness of active power filter (APF) in harmonic wave inhibition. Against the background of single-phase parallel type of APF, its working principle is introduced and its mathematical model is built. Next, analyzed in details is the single-phase parallel type of APF double loop control system based on outer voltage loop and inner current loop, with the specific design procedure of PI control parameters of outer voltage loop and inner current loop presented. Finally, through MATLAB simulation, the designed system control parameters undergo verification. The simulation result indicates such single-phase parallel type of APF based on the double loop PI controller with outer voltage loop and inner current loop can ensure stability of the DC bus voltage and make effective compensation for harmonics over the mid-and low-frequency bands.

In order to solve the difficult problem in lung CT image segmentation, the segmentation method based on Mixture Active Contour Model is proposed and the learning algorithm is presented. It gets the prior information of lung CT image segmentation through Gaussian Mixture Model, couples the penalty term and edge detection of the level set function. Experimental results illustrate the effectiveness of the method based on MACM in solving lung CT image segmentation.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. For the SUAV model of nonlinear coupling characteristics, based on the establishment of the UAV attitude model, this paper designed an attitude ADRC decoupling controller. The simulation showed this ADRC decoupling controller had strong robustness and immunity, and solved the channels coupling between the pitch and roll.

Based on the sub-mini dual ducted UAV dynamics analysis of Newton, and according to the characteristics of the hovering and variable posture mechanism, this paper combined methods of mechanism analysis with system identification to get the attitude model of under actuated sub-mini dual ducted UAV, which contained input variable, output variable and some unknown parameters. Then the subspace method used the real flying data to identify above the attitude model. Finally，the correctness of the identification model was verified.

Recently, the UAV has become the research focus at home and abroad. this paper puts forward a unconventional type: double ducted tilting Subminiature UAV system (SUAV) , and carries out the research of the control system for this SUAV. Since SUAV flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

Since Small Unmanned Helicopter flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

In this work, a general expression of the thermo-acoustic (TA) emission from nanocrystalline porous silicon (nc-PS) is derived by using a fully thermally-mechanically coupled multilayer TA model. This expression takes thermal, mechanical, and geometry properties of every layer in a multilayer structure, as well as the thermal contact resistances between layers into consideration and hence agrees well with the experimental results. Therefore, many fundamental problems in thermally induced ultrasonic emission from nanoporous silicon can be studied.

A period-doubling bifurcation may occur when the estimation error of the rotor time constant exists in an indirect field-oriented control (IFOC) of induction motor drives. Then chaos oscillations appear under some parameter values which are usually tested by the Largest Lyapunov exponents. In this paper, we apply the modified 0-1 method to detect chaos phenomenon instead, and design a controller to suppress chaos in the IFOC system. Simulation results indicate that the proper parameter region of the controller can be obtained with this method, and with the adaptive controller the system can quit from the chaotic state into the stable state effectively and robustly. The 0-1 method identifies chaotic behaviors directly through the time series without constructing phase space. Therefore, the proposed method is not affected by the complexity of the system and is not sensitive to noises.

In order to solve function approximation, a mathematic model of Rational Function Functional Networks (RFFN) based on approximation was proposed and the learning algorithm for function approximation was presented. This algorithm used the lease square method thought and constructed auxiliary function by Lagrange multiplier method, and the parameters of the rational function functional networks were determined by solving a system of linear equations. Results illustrate the effectiveness of the rational function functional networks in solving approximation problems of the function with a pole.

In this paper, the ultrasonic infrared thermography (UIT) technique was applied to detect the composites damage. The frictional heating and thermal conductivity at the location of crack of the composites under ultrasonic excitation was simulated by finite element method (FEM). The excitation parameters including time, amplitude and frequency were studied. The composite involving delamination was detected by the ultrasonic generator. The results show that the UIT can identify the contacting interface-type damages at the surface or subsurface of composites rapidly, for example, delamination, fatigue crack et al.The excitation time, amplitude and frequency are impotent detection parameters. It can be seen accurately and intuitively of location of the damage, and there is no uniform heating problems from the experiment. Suitable coupling material can improve testing quality and eliminate “standing wave” effectively.

Defects in the specimen of missile engine shell was detected by thermal wave image technology in this paper. In order to gain intuitionistic and accurate space structure image of the detected object, subtracting background and high-frequency emphasized filtering method were used to enhance the image quality. Then the defect was segmented from the background using particle swarm fuzzy clustering algorithm, while the defect size and depth were identified quantitatively. On this basis, 3D reconstruction of the defect by thermal wave image was recognized by Volume Rendering method. The results show that the precision of the defect quantitative identification is higher, and 3D reconstruction result is well, which help us to observe the location and size of defects intuitionisticly.