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The research mainly focuses on the performance of the controllable hypocenter in the low frequency band. The hybrid vibration isolation method based on the disturbance observer PID control algorithm is used to improve the excitation signal quality. Based on the analysis of the structure and working principle of vibration isolator, the physical model and mathematical model are established, and the simulation test of ZK-5VIC virtual test vibration and control system is carried out. The experimental platform of hybrid vibration isolation system with low frequency interference is set up. The experiment of excitation and acquisition of low frequency signal is carried out, which provides the theoretical basis and guarantee for the vibration isolation technology in the low frequency range below 3Hz.

1200V-15A 4H-SiC junction barrier schottky (JBS) diodes were designed and fabricated based on SiC epitaxy and device technology. By adopting the proper SBD metal,optimized structures and fabrication process, we succeeded in achieving good balance between blocking voltage and on-resistance, especially at high temperature to 200°C. Furthermore, the fabricated diode have a fast recovery time of 30ns, and its dynamic characteristics are constant at high temperature.

3.3kV and 4.5kV 4H-SiC junction barrier Schottky (JBS) diodes with floating guard rings edge termination have been fabricated. The 3.3kV device with 33μm 2.7E15 cm-3epilayer and 5.5Х5.5mm2schottky contact area has a blocking voltage (Vb) of 3.9 kV and a specificon-resistance (Ron) of 10.5 mΩ.cm2, with a forward current measured up to 50A at VF=3.0V. The 4.5kV device with 50 um 1.2E15 cm-3epilayer and 5.5Х5.5mm2schottky contact area has a blocking voltage (Vb) of 5.1 kV and a specificon-resistance (Ron) of 22.9 mΩ.cm2, with a forward current of 30A at VF=3.7V.

Results are presented for the silicon carbide (SiC) vertical channel junction field effect transistor (VJFET) fabricated based on in-house SiC epitaxial wafer suitable for power devices. We have demonstrated continuous improvement in blocking voltage, forward drain current under high temperature. The SiC VJFET device’s current density is 360 A/cm2 and current is 11 A at VG= 3 V and VD = 2 V, with related specific on-resistance 5.5 mΩ·cm2. The device exceeds 1200 V at gate bias VG = -10V. The current of the SiC VJFET device is 4 A and the reverse voltage is 1200V at the 200 °C high temperature.

Because of the limit of the optical lens’s depth, the objects of different distance usually cannot be at the same focus in the same picture, but multi-focus image fusion can obtain fusion image with all goals clear, improving the utilization rate of the image information ,which is helpful to further computer processing. According to the imaging characteristics of multi-focus image, a multi-focus image fusion algorithm based on redundant wavelet transform is proposed in this paper. For different frequency domain of redundant wavelet decomposition, the selection principle of high-frequency coefficients and low-frequency coefficients is respectively discussed .The fusion rule is that,the selection of low frequency coefficient is based on the local area energy, and the high frequency coefficient is based on local variance combining with matching threshold. As can be seen from the simulation results, the method given in the paper is a good way to retain more useful information from the source image , getting a fusion image with all goals clear.

As an emerging research issue of the tourism and electronic commerce, tourism information searching has become the focus of scholars. The foreign scholars have achieved fruitful results since 1990s, while studies on this field are more actively at home these years. The current study aims at helping the researchers better by comprehending the existing finds and recently perspective, we summarized and categorized the findings of research in recent years, and expect to present an overall and timely analysis.

In this paper we present a compound anisotropic diffusion filter algorithm to apply edge sensitive ICOV operator in NCD model. According to the correlation coefficient of the ICOV operator, we obtain effective nonlinear denoising. The experiment have validated that our algorithm have better effect in smoothing and better ability in edge preservation.

Currently,the ultrasound image has been widely used in diagnosis and treatment of clinical medicine,the results obtained by the diagnostic accuracy and reliability of the image is directly related to the effects of diagnosis and treatment.Because ultrasound images in the imaging process inevitably contaminated noise,thus the research of inhibiting ultrasound image noise is one of the important issues in domestic and international ultrasound imaging techniques.This paper studies the multi-scale analysis and wavelet thresholding two theories,put forwarda denoising algorithm about combining the Nonsubsampling contourlet transform and a new threshold function,experiments show that the new algorithm can not only good at suppressing the noise of ultrasound images,and can better retain image edge and texture details.

To seek a way non-invasive and adaptive to differentiate the normal and abnormal heart sound signals in order to provide more valuable reference method for clinical diagnosis. This paper made the largest Lyapunov exponent as the mainline. According to the unity of the whole signal in different stages, a method to study the characteristic in stage was proposed. First of all, we made phase space reconstitution to the typical seven normal and abnormal heart sound signals. Then, we calculated the largest Lyapunov exponents according to the phase space reconstitution parameters. At last, we compared and analyzed the mean values of the largest Lyapunov exponents. The mean value of the normal heart sound signal in S1 was 0.145, which was much larger than that of the abnormal signals and the mean value of the normal heart sound signal in S2 was larger than that of the abnormal ones, too. This conclusion means that there are chaotic characteristic in the heart sound signals and the degree of chaos in normal heart sounds is higher than that in the abnormal heart sound signals.

The tree-like structure is a branch of space bionic structures,belonging to the Bionic Architectural Structures. Cast-steel joints with branches are the keys to build the tree-like structures.They are used widely,and the most common joints in our projects are cast-steel joints with two、three and four branches. The cast-steel joints with two branches are planar,while the joints with three and four branches are spatial.Until now,the basic theoretical researches about the cast-steel joints with branches are also relatively scarce.This paper did researches about mechanical properties, calculation methods and structural optimization of the cast-steel joints with three branches deeply and systematically. The result shows that the bending moment has a big influence on the value of the max stress. And the three main failure modes of the cast-steel joint with three branches are yield of the main tubular along the axial direction, local buckling at the connection of the main tubular and branches, and the tearing out of the branches.

It is an urgently problem to be solved that how to test a weapon system-of-systems capabilities in a joint operational context. Firstly, based on the capability assessment of weapon system-of-systems, a procedure of weapon system-of-systems capabilities evaluation strategies design space is proposed. Secondly, supported by agent-based simulation tools, an exploratory analysis example is given which uses the fractional factorial design and stepwise regression fit. This paper makes a better try on the measures selected of the system-of-systems capabilities in the early period of weapon equipment acquisition.

Whether in the aerospace, or seismic exploration, as well as high precision operation of all trades and professions, low-frequency interference directly influences the instrument monitoring and detection precision, resulting in insufficient accuracy of the implementing agencies. The passive vibration isolation method was used by most high accuracy equipment at present, the efficiency of isolation can only achieve 60%-70%, that will have influence to the extremely precision equipment certainly. In this paper an active vibration control system was realized by using single-chip microcomputer and the PID control algorithm. System simulation model was built and experimental tests had been conducted. The interference eliminated more than 80% for 3Hz and below,can effectively improve the precision equipment to work under the low frequency interference.The system provided an effective method to suppress the low frequency interference.

For considering the losses of pre-stress in suspend-dome structures, an improved rigid cable method was proposed. The main character of this method is the temperature stress is applied to corresponding element to compensate the loss of pre-stress. The relationship between temperature and pre-stress loss is deduced, which can give the definite num of temperature needed to add on the corresponding elements. An example and engineering application are discussed. Results show that the improved rigid cable method is effective and applicable.

Machinery, especially, lead electrolysis Non-ferrous Metallurgy industry needs higher and higher temperature accuracy in manufacturing equipments by accompanying the development of the science and technology. During the process of lead electrolysis manufacturing equipment, the anode plate vertical casting system is a producing device which aims to complete the casting of the anode plate. However, simple cool system and poor cool effect and lower production efficiency of the domestic anode plate manufacturing equipment are the common short comings which exist currently. Therefore, we designed in Solidworks based on a comprehensive analysis of the mechanical structure of the mold, and obtain the time of right temperature of moving mould in a stable state, thought to verify the rationality of the design of the equipment cooling system.

An ultrasound velocimetry system based on single-chip CC2530 was designed, this combined the transit-time velocimetry and Doppler velocimetry, achieving the monitoring of wireless sensor network to the speed of the car. The Proteus software simulates the hardware circuits of the ultrasonic transmitter and receiver module. An ultrasound velocimetry system measures high-speed by the ultrasonic Doppler principle, it measures low-speed through the transit-time principle, the speedometer system was verified by the simulation technology. The design has a low complexity, low power, low cost, small error, application and so on.

According to the problems of slow weighing speed and low precision resulting from sticky foods caking in quantitative packing weighting, the mechanical structure, the circuit system and the software algorithm were designed in this paper. To improve the weighing speed and precision of sticky foods, the double-tube spiral feeding machine and a special structure of scale bucket were adopted in mechanical structure; a programmable AD8555 was used as weak signal amplifier of weighing sensor and a 32-bit microprocessor LP2134 was utilized as the core of the circuit system; the piecewise weighing method, FIR software filter and the differential algorithm are applied to send command to executive mechanism in program design.

To improve the ability of aircraft sortie generation, we propose a genetic method to model the aircraft spotting allocation optimal problem, and transform it to a constrained optimal problem. Sortie path and time from parking spot to catapult are calculated by pseudospectral method, and then the genetic algorithm is given in detail. Finally, an aircraft sortie scenario is given to prove our method. Simulation results testify our method satisfies the requirement of scheduling optimal and can help commanders on flight deck to control aircraft spot allocation.

Magnetic flocculation technology was investigated for the removal of copper and zinc ions from simulated tin smelting wastewater, and the effects of magnetic powder dosage, flocculant dosage, and pH on the removal of copper and zinc ions were estimated. The results show that the effluent quality is poor with magnetic powder, PAC and PAM separately dosed, but when magnetic powder is combined with PAC or PAM, the excellent effluent quality is obtained with the removal rate of the copper and zinc ions of more than 90% and 70% respectively. In addition, under the condition of magnetic powder dosage of 30g/L and PAC dosage of 60mg/L, pH show more significant effect on zinc ions than copper ions with pH increased from 5 to 10, and the removal rate of zinc ions increase by about 24%, while the removal rate of copper ions only increase by about 2.5%. Compared with the system with single metal ion, the coexistent ion system has excellent heavy metal removal efficiency, namely the copper ions removal rate increase by 3.42%, and the zinc ions removal rate increase by 0.46%. Moreover, magnetic flocculation technology presents the characteristics of shorter time of flocculation and sedimentation, smaller volume of the flocs and faster separation velocity.

The scheduling mechanism for cloud computing platform is described at first in this paper. Secondly the analysis of the B2C auto-negotiation process and the characteristics of its computation resource scheduling mechanism are given. Finally some computation resource scheduling strategies for B2C auto-negotiation in cloud computing platform are discussed.

The method of using efficient inert projectile with highly efficient propulsion has great potential for the rapid and efficient excavation of rocks and ore in both surface and underground. In this paper, a series of numerical experiments were performed to simulate rock fragmentation resulted from steel fiber reinforced concrete (SFRC) projectile by using hydrodynamic finite element code AUTODYN. The fully coupled method was been adopted, in which the limestone, molded using Lagrangian mesh, is coupled to SFRC projectile molded using smoothed particle hydrodynamics (SPH) method. The numerical model was verified by comparing the simulation results with the field experiment data. Furthermore, the effect factors of geometric parameters of SFRC projectile and fibers content on the muck production were also discussed. The results of this study suggest that numerical simulation could be substituted for field experiment used for performance assessment of SFRC projectile.

This paper, based on the practical engineering of the steel structure of Henan Shangpin food Co. LTD, introduces the design of a light-weight steel structure with three-span gabled frames, and discusses the solution of the large suspended loads. By taking the steel quantity as the target, the depth calculations and statistical analysis of the reasonable value of the column spacing were carried out. The results show that the large suspended loads should be imposed in the form of live load. When the column spacing is about 8m, the steel quantity is the lowest.

In order to solve the problem of siphon rainfall recorder’s hard to control automaticly and the measurement error when siphoning, we research the Automatic forecasting system based on double barrel double siphon rainfall recorder and ARM processing terminal. By using double barrel double siphon structure and weighing cell, we eliminate the rainfall error caused by siphon loss, and achieve the automatic collection of rainfall data.

This paper introduces the structure and working principle of the designed copper anode lifting platform. According to the actual working conditions and the structure of the lifting device, hydraulic system of electro-hydraulic proportional synchronous lifting device is designed and its working principle is analyzed. This paper takes the electro-hydraulic synchronization system as a research subject, whose mathematic model is established. To solve the synchronization accuracy of the hydraulic cylinder movement in the lifting process, a model reference adaptive controller is designed which is based on hyperstability theory. Both system simulation models of traditional PID control and adaptive control are established respectively in the software of Matlab/Simulink. Through the simulation result we can learn that adaptive control is batter than the PID control. Two hydraulic cylinders synchronization error is less than 0.02mm.

In this paper, introduced the structure and speed control principle which are the molding pressure roller of lead flake. Then, the co-simulation technology of AMESim and ADAMS is used to build a mechanical model of the molding pressure roller in ADAMS and build the model of hydraulic system and separation algorithm of PID controller in AMESim. Finally, according to the co-simulation model to analyse the molding pressure roller of lead flake in AMESim simulation interface. Simulation results show that the design of speed control system has good dynamic performance.

Pneumatic pump use compressed gas as power source, outputting straight reciprocating motion. It is widely applied in high pressure airless spray machine. Reversing mechanism is the core component of pneumatic pump. According to the different ways of distributing and reversing gas, pneumatic pump reversing mechanism can be divided into two major categories of pneumatic control type and mechanical type. We summarize the history of the development and the present situation of research and compare various reversing mechanisms in the realization principle, design of structure, manufacturing, vibration noise and cost of production etc. Then we put forward the direction of its research and development, providing theoretical basis for the subsequent development of high quality and efficient pneumatic pump.

Based on the theory and method of innovative design aided by patent knowledge, this paper analyzes the existing patents about pneumatic pump reversing devices and the other patents, and establishes the library of principles and structures which can achieve reversing function. As there are many shortcomings of existing pneumatic pump reversing devices such as a lot of collisions, big noise and difficult to manufacture, based on the principles and structures which can achieve reversing function, this paper proposes two new pneumatic pump reversing devices to help solve these problems. Compared with the existing pneumatic pumps, the new devices have many advantages, such as simpler structure, less collision, less noise and less cost.

The design and analysis of the large span steel latticed shell structure in site of Yuyao TianLuoshan is introduced, and some key problems are dwelled on in this paper. By the geometrical nonlinear finite element method, the nonlinear stability analysis is carried out. The buckling modal and the whole course of instability are shown by two analysis method, the eigen-buckling analysis and the geometrical nonlinear finite element method. The influence of spring support to the stability of the structure is analyzed. It is shown that the structure has good wind-resisting capacity, which is fit to the circumstance near sea with lots of typhoon. Large compressive membrane stresses arise in the structure under the condition of temperature rise, leading to a significant reduction in the stability load-carrying capacity of the structure.

With the purpose of lowering the problem to compile and maintain for GIS users, this paper will demonstrate how to implement on power GIS editing system based on ArcEngine under .net environment. With the help of the GIS and the complex science of geometry network data organization, it emphasizes the maintenance function of the electrical data to realize the analysis of the connectitvity of the whole network of the line.

This article summaries the importance of the technology of landslide monitoring, also describes main methods of landslide monitoring and new means of analysis of landslide deformation, at the same time, it briefly describes the classification of detection technology of landslide deformation and points out the prospect of engineering application of landslide monitoring technology.

The interfacial mechanical characteristics in anchorage zone of grouted bolts influence the ultimate capacity of bolts directly; a push-out test was carried out at the lab to study the interfacial mechanical characteristics in the case of bond failure happening at the grout-rock interface, leaned from some scholars to test methods for analysis of concrete microstructure instead of rocks. The commercial finite element software ANSYS method was adapted to analyze the dilatancy effect on the concrete during the grout was pushed out. Using conversion between compressive strength and tensile strength of concrete cube, the tensile strength can be calculated, as the basis for destruction of the concrete matrix.

Many sluices were damaged seriously after several decades’ use. In sluice safety level’s classification standard, there are quantitative indexes and qualitative indexes. Principal component analysis was used to evaluate the sluice. First the data were standardized, correlation matrix was got, and then confirmed principal components and weight, through this step principal components’ value and total value were received, finally sluice risk grades were determined and they could be ordered. The result is objective and reasonable, so we assess sluice easily.

This paper explains how the Lignin peroxidase and Manganese Peroxidase from Coriolus Versicolor were co-immobilized by chitosan microspheres.It studies kinetic character of the enzyme after co-immobilization.Optimum Lip and MnP activity obtained at 30-35°C for 14 hours in pH 8.4 glutaraldehyde solutions during immobilized to chitosan microspheres which prepared by coagulation in NaOH: methanol=3:2. When kept at 50°C for 6h, more than 80% of the immobilized enzyme activity remained, while the free enzymes were inactive under the same conditions. The co-immobilized enzyme can remain 70% activity after two weeks while both of the free enzymes inactive. Compared with the free enzymes, temperature and time stability of the co-immobilized enzyme was considerably improved.

The fly ash and ash of different biomass power plants are selected as research objects, of which the combustion characteristics are studied. At the heating rates of 50°C/min, at the final reaction temperature of 900°C, and under the condition of air as carrier gas, weight loss curve and weight loss rate curve are analyzed respectively. TG, DTG curves of fly ash and ash from different power plant are gained, different combustion conditions are studied, and combustion kinetic equations of different biomass fly ash and ash are established, kinetics parameters are obtained by the Coats-Redfern method. Besides, combustion condition and reburning feasibility of different biomass fly ash and ash are analyzed, which provide a theoretical support for biomass power plant operation, such as improving their fuel burn rate.

This paper makes study on the 42CrNiMo gear contact fatigue strength, applying the rapid measure method of the gear contact fatigue stress value with a few gear samples to get the estimated value of the gear fatigue limit value precisely and rapidly. And the gear fatigue life curve and fatigue damage accumulation curve are got by MATLAB simulation. Comparing with the traditional test method, this method can reduce the cost and save the time.

There have some advantages like as Good working conditions, High Security, Guaranteed production capacity and Low loss for Open pit mining, therefore the degree of opencast mining increasing. In this paper numerical simulation and limit equilibrium are used for Stability of west project of side slope which are under the conditions of Normal and Saturation. Draw slope stability results under the two conditions in order to take appropriate measures to provide appropriate post- mining safety protection.

This paper introduces the installment method of experimental machine and gears, and the definition of stress levels, based on the contact fatigue experiment of 18Cr2Ni4WA carburizing and quenching gears, the few experimental points combination method was applied. The experimental points data was obtained by failure criteria. The S-N curve is fitted according to experiment data, and the experimental points data processing method is also explained in the paper.

Pentachlorophenol (PCP), metallic oxide and ball-grinder medium steel beads are ground together in a ball-grinder under room temperature and pressure to degrade PCP. A AgNO3 standard solution was used to titrate the Cl--containing solution made from grinding product. The dechlorination rate used to show the degradation result of PCP was calculated through the amount of AgNO3 standard solution. The results show that dechlorination rate is increased with grinding time increasing, and the product shows a black hue after 2.5h grinding, which might be a sigh of elemental formation carbon; The bigger the CaO/PCP molar ratio is, the better the dechlorination rate is. With the molar ratio of 50:1,the dechlorination rate is over 90%, while 60:1 for almost 98%

The PLA/Rice straw fiber composites with various content ratios were prepared by using an internal mixer and a flatten press. The thermal properties, interface effect and mechanical performance of as-prepared PLA/Rice straw fiber composites were studied by mechanical performance measurement, TG, DSC and SEM technique. It was found that increasing the content of rice straw fiber leads to the decrease of the melting temperature while the improvement of the crystallinity of these composites. Introducing the rice straw fibers into PLA matrix does not result in any enhancement of mechanical property. However, the tensile strength of the composite increases as the content of rice straw fiber increases from 10% to 30%. The interface effect between fibers and PLA was obviously observed by SEM photo. It was thought such an issue could be improved by the addition of appropriate coupling agents into the composites.

In this study, the springback law of generatrix direction, circumferential direction of tailor welded blanks (TWBs) cylinder shallow shell impact from blank holder force, punch profile radius and sheet thickness was researched by finite element analysis, which was compared with non-welded blanks. The results show that: in the circumferential direction, with the increase of blank holder force, the trimming springback of the tailor welded blank of the thickness combination of 1.2mm and 0.8mm (TWB1208) is decreased firstly and then increased, which is larger than that of the non-welded blanks of 0.8mm and 1.2mm. With the increase of punch profile radius, the drawing and the trimming springback of TWB1208 are both increased, and after trimming, the both springback are greater than that of the non-welded blanks. With the increase of the quadratic difference of thickness, TWB1208, TWB1612 and TWB1608, the drawing springback is decreased, and the trimming springback is gradually increased. In the generatrix direction, when blank holder force is less, the distortion deformation of TWBs is serious, and after the trimming, it is decreased according to the increasing blank holder force. With the increase of punch profile radius, the distortion deformation is larger. The greater the difference of thickness is, the more serious the distortion deformation is.

Tooth contact analysis (TCA) is an effective tool for meshing analysis of the double circular arc profile spiral bevel gear (DCAPSBG), and it is the basis of loading tooth contact analysis and finite element analysis. The TCA application is developed by Visual Basic and MATLAB mixed programming method, this paper compared the results of the TCA application analysis with the results of contact area check experiment on one pair of gears with given parameters. The TCA application had been verified by real experiment, this provided an effective approach for the design of DCAPSBG.