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The factors that influence environmentally-friendly powder rubber powdering are introduced. Types and dosage of isolation agent, types and dosage of coagulant, environmental antioxidant, condensation temperature, stirring speed on the effect of powder rubber are examined. Thus a simple method to prepare environmental powder rubber is provided.As a physical variation of traditional bulk rubber, powder rubber can change the situations that high energy consumption and high labor intensity of the former. And it also can make the mixing process become continuous, automated, energy-saving and so on. In recent years, with the progress of rubber processing industry, the demand of powder rubber increases rapidly. And there is a intense requirement of supplying environmentally-friendly powder rubber[1-3]. So it is very important to do this experiment.

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.

Theresistance of slurry pipelinetransportation has greatly impact on slurry transportation system. In order toimprove transportation efficiency,energy utilization rate,taking theappropriate drag reduction technology has a very important significance.Thispaper presents drag reduction technologies for slurry transportationapplications,including micro-bubble drag reduction technology and vibrationdrag reduction technology.

It is very important to recycle and deal with them effectively for environment protection resources saving. In this paper, on the basis of relevant knowledge of classified recycling, we combine the situation of our surveying actually, establish electronic information platform which is suitable waste electronics. More important being, we design a recovery bins can be classified recycling battery. What’s more, according to the waste electronics recycling system, we put forward to increase the recovery rate and the better classified recycling.

In view of the fact that the complex control of car moving device, its small application range, the difficulty to reach the accurate location of vehicles and so on, therefor a new design and research for a car moving device of remote control is proposed; The Mecanum wheel is chosen to achieve the omnidirectional movement, so that the vehicle can reach the predetermined position quickly. The electro-hydraulic push rod is used to realize the automatic lifting ,and it is also convenient and efficient; In addition, AT89C52 microcontroller which cost less but can meet the requirements realize the control.

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. Neural network which has a strong learning ability, is able to learn from the sample and can adapt to changing learning condition. Thus, the neural network can be used to simulate the learning process of operator, and operating characteristics information of objects can be excavated from the measured data, and accordingly change the parameters of the controller and decoupling network. This paper presents a attitude control algorithm of the dual-ducted SUAV which combine ADRC algorithms with neural network decoupling control algorithm, to design a SUAV decoupling controller. The simulation results showed that the attitude control channels between the pitch and roll were independently of each other, indicating a good solution to decouple the coupling between the pitch and roll channels based on neural network algorithm.

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.

Chaos is extremely sensitive to initial conditions, which makes the system with even smaller initial amount of changes can eventually evolve into a very different result. In an indirect field-oriented control of induction motor drive when estimated errors exist, within a certain range of parameters the system may evolve into chaotic motion through period-doubling bifurcation. In this paper an adaptive controller for synchronizing two indirect field-oriented induction motor drives under chaotic state is presented. Simulation results show that with the state-error feedback controller, synchronous state may be achieved rapidly and robustly.

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.

Objective To compare the biomechanical properties of two lag screws proximal femoral nail(PFN) when they are placed in different points of the neck of femur in the treatment of intertrochanteric fracture of femur. Method Three pairs of fresh femora of adults aging from 55 to 65 are taken. They are made into AO type A1.1 intertrochanteric fracture. Fracture specimens are fixed by PFN. The mechanical testing machine loads the fracture model at a speed of 0.5mm/s. The stress distribution of the fracture broken ends, the opening angle of the fracture broken ends, and the relationship between load and displacement are recorded respectively. Result The stress change of the group inferior of the small trochanter is smaller than that of the group superior. The opening angle of the fracture of the group inferior is smaller than that of the group superior. The displacement of the top of the femoral head of the group inferior is smaller than that of the group superior. Conclusion The performance of the group inferior is better than that of the group superior. Thus it can be concluded that when two lag screws of PFN were placed in the middle and below 1/3 part of femoral neck, the biomechanical properties are better, the structure is relatively more stable, and the stress bearing is more reasonable.

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 order to solve the impact of environment on reasonable production capacity of large mine, analyzed the main factors of environmental pollution affecting the coal mines, illustrated the coordination and interaction of various subsystems of the industry ecosystem in chart and used the environmental quality assessment to determine the mine environment grading and partition, determine the reasonable capacity of the large mines within the bearing capacity of the environment, present environmental protection measures in different areas.

Low-energy ion implantation is a new mutation source, which has the characteristic of light damage, high mutation rate, and a broad spectrum mutation. In order to obtain industrial strain with high L-(+)-lactic acid yield, the original strain Lactobacillus casei CICC6028 was mutated by nitrogen ion beam implantation. It was found that the original strain had a higher positive mutation rate when the output power was 10keV and the dose of N+ implantation was 50×2.6×1013 ions/cm2. The mutant N-2 was obtained for many times screening and its yield of L-(+)-lactic acid was 136 g/L which was improved by 38.8% compared with the original strain whose yield of L-(+)-lactic acid was 98g/L as the cultivation time was 120h. The initial screening methods were also studied in this work but it was found that the transparent halos method was unavailable, so the initial screening was performed by shake flask fermentation. HPLC chromatogram was used to analyse the purity of L-(+)-lactic acid that was produced by the mutant strain N-2, and the result indicated the main production of N-2 was L-(+)-lactic acid and there was no other acid almost.

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.

The paper studied on parameters of ion implantation into lipid producing strain Rhodotorula glutinis and lipid extration technology. It was found that the strain had a higher positive mutation rate when the output power was 10keV and the dose of N+ implantation was 80×2.6×1013 ions/cm2. Then a high-yield mutant strain D30 was obtained and it’s lipid yield which was 3.10 g/L increased by 33.05% than that of the original. Additionally, statistically-based experimental designs were applied for the optimization of lipid extraction by acid-heating coupling ultrasonic technique. By a Plackett-Burman design, it was found that three factors, treatment time of HCl (p=0.036) , ultrasonic time (p=0.0105) and rate of extracting solution (VCHCl3:VCH3OH) (p=0.0105), had significant effect on lipid extraction. Subsequently, these significant factors were optimized using response surface methodology (RSM), and the optimized parameters of lipid extraction were as follows: 34 min for treatment time of HCl, 7.5 min for ultrasonic treating time, 1.9:1 for rate of extracting solution (VCHCl3:VCH3OH). Finally the fermentation characteristic of high-yield mutation strain D30 was studied, when fermentation time was 10 d, it’s lipid yield increased to 7.81 g/L

Experiments on adiabatic temperature rise are systematically carried out in this paper, the characteristics of adiabatic temperature rise of concrete with different mineral admixtures are compared. The influence of binder amount, water-binder ratio, placing temperature and superplasticizer is also studied. The results reflect that binder is the main factor affecting adiabatic temperature rise, mineral admixtures such as fly ash can significantly reduce the rate and amount of heat development, large quantity substitution of slag in concrete can relieve the concentrative heat liberation, the retarded superplasticizer can prolong the exothermic process effectively and high placing temperature has adverse effect on temperature control of mass concrete.

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.

With ion implantation, a high xylanase-producing strainAspergillus nigerBU99 was selected. Different late acting carbon sources (wheat bran, wheat straw, corncob and bagasse) had an effect on enzymatic production. Additionally, it was found that fast acting carbon sources (lactose, galactose, sucrose, glucose and maltose) put into the media affected on xylanase production too. Severe catabolic repression was observed in the media with lactose, but other sugars (galactose, sucrose, glucose and maltose) could increase the production of xylanase compared with the control. The production of xylanase was improved too when corncob flour was hydrolyzed by α-amylase, cellulase or/and glucoamylase. Additionally, it was found that the production of xylanase would be almost higher at 60h when the media contained glucose or were hydrolyzed by enzymes.

An explicit dynamic Galerkin meshfree formulation under the updated Lagrangian framework is presented to simulate large deformation damage and failure process in geomaterials. The failure initiation and development are characterized by the pressure sensitive Drucker-Prager plasticity coupled with the isotropic energy-based damage theory. A stabilized conforming nodal integration based on non-local gradient smoothing is employed to improve the computational efficiency and to regularize the material instability arising from strain localization. The capability of the proposed methodology to model the evolution of dynamic failure in geomaterials is demonstrated through a numerical example.