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A processing method based on VFD Filter is proposed in this paper for implementing the high dynamic simulation of TT&C signal. The method adopts the store-delay way which could implement integer delay for static data and adopts the VFD filter to implement high accuracy fractional delay for the integer delay signal.The simulation and analysis results show that the proposed method not only can accurately and commendably implement high dynamic simulation for TT&C signal,but also suits for different form signal. It provides a good way for dynamic simulation in the compatible test of TT&C equipment.

In the high power industrial control network, due to the large user base, the data traffic is plodding, the data formats are inconsistent, the network data storm is difficult to monitor. A kind of high power industrial control network data monitoring and control system is designed under non-uniform formats. The network node information collector is designed, the data is collected, and the data collection result is taken as the mathematical expectation, the mathematical expectation is trained. The problem of data flow storm statistics is solved. In the system, the format conversion function is added, data storm monitoring results is taken with the format conversion, and they are stored as text format. The monitoring program reads and displays the result, the difficulties brought by the format is not unified are solved. System test results show that the system can monitor the large power industrial control network data storm, the monitoring result is precise, and it can make the formatting process fast. A size of the generated result file is 18.1%, of the original file, and can fully reflect the network data storm characteristics, the effect is perfect.

An informal landfill is an open dump that pollutes the underground environment because it lacks an impervious liner. The leakage of such a landfill is unidirectional and thus difficult to directly test. This study uses electrical imaging survey to evaluate the pollution of the underground environment of an informal landfill for municipal solid waste in Beijing. We hypothesize that every location has a specific resistivity resulting from the leachate. We use the membership function of fuzzy mathematics to quantitatively represent the pollution of the underground environment in the sanitary landfill. The results are consistent with borehole data.

Combining the energy limit theory and the ANSYS finite element simulation analysis, this paper has designed the new integrated quartz crystal resonator and has used oscillator circuits to carry on the experimental comparison on its temperature-frequency characteristic in high-low temperature chamber. The experimental results show that the curve of its temperature-frequency characteristic is cubic in the coordinate system, which is basically consistent with that of the single electrode resonator. The frequency change of each resonator on the same substrate is basically the same when they are in the same circumstance and stimulation. According these similarities, this paper can implement differential processing on output frequencies of different resonators on the same substrate, which can effectively restrain the influence that temperature imposes on frequency.

By analysing the wafer, the electrodes, etc. according to the energy limit theory and the ANSYS finite element simulation, in this paper the author has designed the integrated quartz crystal resonator and oscillator circuit, and has carried on the experimental comparison on the stability of the integrated resonators, which have different structure, different electrode material and thickness. The experimental results show that the frequency stability of quartz crystal resonator is not only related with the electrode material and thickness, but also related with the structure. Under the same condition, resonator of asymmetric structure has better frequency stability, and the stability of Au-electrode was better than others, and its magnitude could reach 10 10. With the increase of the electrode thickness, the resonator oscillator stability will be improved.

Analyzing stress distribution of the thin circular quartz wafer subjected the radial force through the ANSYS finite element simulation, as well as the theoretical simulation, this paper designed two integrated quartz resonators with different structures and carried on experiments on force-frequency characteristic of resonators. The experimental results show that the resonators force-frequency characteristic is not only closely related to adding force azimuth, but also the electrode size and position. And when force azimuths are same, integrated resonator with asymmetric structure has better force-frequency characteristic, its force-frequency conversion coefficient could achieve 551.8Hz/N after electrode was evaporated with Au.

Based on the primary factors that influence site selection for National Strategic Reserve Depots of Refined Petroleum Products, this paper establishes a comprehensive system of evaluation indexes. In accordance with the different tiers of the index system, this paper puts forward an evaluation model based on the multi-tier fuzzy evaluation method. Then the evaluation model is proved to be reasonable, effective and feasible via case analysis and calculation.

Nowadays, the operation of orchard vehicle which is used in China has the disadvantages such as single function poor automation level etc. Therefore, it can hardly adapt to the complex environment in orchard. The electric vehicle that powered by electrical drive motor can not only save energy, but also achieve the goal of controlling more conveniently and efficiently. Some electrical vehicles in China can take a variety of steering modes. However, most orchard vehicles lack of targeted terrain design. Electric four-wheel independent drive and steering vehicles have strongly strengthened this weakness. This paper uses four-wheel independent drive & four-wheel independent steering structure and completes the design of the control system. The aim is to achieve five different orchard vehicle driving modes which based on microcontroller system, real-time feedback and achieve differential speed calculating model through the multi-channel sensor in the steering modes. Thus, it can ensure the slip angle within the allowable range and driving stability. It also proposes the design & manufacturing of wireless remote control device and operation panel in order to simplify drivers operation and increase the efficiency.

A new method for measuring and identifying characteristic parameters of moving-coil geophones is proposed in this paper, where sine sweeping signal is considered as the electric excitation instead of the traditional vibrational excitation. A mathematical model of moving-coil geophone is constructed and the frequency response of 6-parameter is obtained in this paper. Using the expression as the objective function for fitting measured amplitude-frequency curve, geophones characteristic parameters are obtained. Finally, verification test is performed and the factors affecting measure accuracy are analyzed. The experimental results indicate that the presented method is suitable for production and maintenance, especially for in-situ calibration of geophones. This work provides a new way to design and manufacture portable geophone parameter testers.

In the microelectronics manufacturing domain, a linear platform plays an important role to achieve high speed, high position resolution and a long stroke. In this paper, a concept of macro/micro platform is presented by combining with a voice coil motor and a piezoelectric stack actuator. This macro/micro system was investigated by mechanical analysis, related property indices and so on. The static and modal characteristics of the macro and micro system were calculated by finite element method, and then some important conclusions were obtained. The displacement and stress distribution of macro and micro system were disclosed. The relevant change trends of displacement and stress under the different load were investigated and the first four natural vibration modes of the macro system were obtained. Finally, a structure model of macro/micro concept was designed and established by above calculation. These results provide a solid theoretical support for its application in the microelectronics manufacturing equipments.

In order to realize the effective segmentation of the rice leaf lesion, how to remove background interference and isolating single rice leaf from collected images is the basis of disease classification and recognition. The main body information of the images collected under the simple background of lighting box and field contains only single leaf, so we can use the normal way to detect the blade edge. However, because of the outside interference under the background of field, parameters can't be quantified and the treatment effect of using ordinary edge detection methods is bad. This paper takes advantage of the characteristics that phase consistency test methods that protect them from the image contrast and brightness change and have a strong ability to resist noise to realize complete extraction of the main blade edge in the rice leaf image under the complex background.

Based on rolling technology of stretch reducing mill group, by using large-scale general-purpose finite element analysis software ANSYS/LS-DYNA, a 3D thermal mechanical coupled numerical calculation of stretch reducing process, stress field, strain field, temperature field and the distribution of wall thickness were obtained, as well as the distribution of asymmetrical metal deformation when pipe passing every mill. The results of numerical simulation provide a reasonable cause for uneven wall thickness distribution, guiding the design of stretch reducing process.

In order to discuss more convenient the relationship of coating morphology and frictional wear in processing, according to the one correspondence of gray image and actual surface topography, this proposed a method of digital image processing. with binary image of different load F and serial rubbings obtained pits distribution rate T and the optimal range in wear resistance. It calculated fractal dimension D based on the Discrete Fractional Brownian Random Field, summarized the osculating relationship of D and surface topography in frictional wear.

Sustainable energy generation is becoming increasingly important. Our oceans are largely an untapped source of energy. This paper presents an innovative design method for converting the linear motion of ocean waves into electricity energy. The design principle and the construction details have been presented.

Vegetable quality safety is the current hot issue that arose government, social concern and global attention; it is also the key problem that must be solved for the present stage of implementation of agriculture and rural economy structure strategically adjust, enhancing produce competition ability. Based on the analysis of the key points of quality and safety of agricultural products on the basis of monitoring, this paper introduces vegetable quality safety supervision information facility equipped for engineering application, and takes the prospect of agricultural product quality safety supervision information tech90nology equipment.

The forming compact process of the concrete brick in vibration is simulated based on three-dimensional discrete element method (3D-DEM) where the crude granular materials of the concrete brick are simplified into two spherical particles of different sizes. There are three zones affecting compactness in vibration including porous zone, compact zone, and compact stable zone. The compactness's variation of the different heights and the above three zone are analyzed when both the amplitude and the frequency are different. By orthogonal experiment the result is showed that the average compactness is best when the amplitude is about 4 mm and the frequency is 100 Hz.

Per-Pixel lighting can greatly improve the computational efficiency because of the model has been completed the hidden and visibility judge processing. However, each pixel brightness values need to recalculate when the viewpoint changes. And per-pixel lighting will still be constrained computational efficiency in the case of greater pixel number. In this paper, a fast calculation method for view-dependent per-pixel lighting under a fixed light source is proposed, and a symmetric relationship between pixel brightness value and specular reflection was given. Finally, the brightness under the current viewpoint can calculate fastly. Experimental results show that this method has an efficient lighting calculation than the method of per-pixel lighting and hardware-accelerated lighting calculation.

This paper studied the influence of heat treatment on the pyrophyllite structure and acid-soluble properties of alumina. Qualitative tests had been performed in studying pyrophyllite crystal at different temperatures by XRD, TG-DTA, FT-IR and quantitative analysis of Al2O3. The quantitative titration method studied the dissolve characteristics of the different heat treatment samples in different acid conditions, and then a numerical simulation was done. The results showed that at temperatures below 480 °C, the pyrophyllite did not change the basic structure. 480~700 °C dehydroxylation reaction occurred, and the structure water of pyrophyllite is removed, and then turned into partial pyrophyllite. Dissolution experiments showed that after thermal activation the behavior of alumina in acid the dissolution was different, which was affected by hydrochloric acid concentration, heat activation temperature and acid leaching time. When the calcinations temperature was 700 °C, the dissolution amount of alumina was largest. These works could provide some theoretical basis for further application of pyrophyllite research.

Pyrophyllite was the cheap, environmentally friendly alumina silicate clay minerals. This paper studied optimization of conditions for extraction of acid-soluble Al2O3 from pyrophyllite. Qualitative tests had been performed in studying pyrophyllite crystal at different temperatures by using scanning electron microscopy. Dissolution experiments showed that after thermal activation the behavior of alumina in acid the dissolution was different, which was affected by hydrochloric acid concentration, heat activation temperature and acid leaching time. When the calcinations temperature was 700 °C and hydrochloric acid concentration was 25%, the dissolution amount of alumina largest. The fit results indicated that the research for the relationship between dissolution and time by Using Exponential function series Asymptotic1 model to fitting match was the best. So the above function could be used to estimate each time the dissolution of alumina from pyrophyllite in hydrochloric acid.

The standard k-ε turbulence model was used to simulate the flow of a new unsmooth surface - dimple concave surface in air and the drag reduction coefficients of both unsmooth surface and smooth surface with hemisphere of 0.4mm radius were presented. The result showed that this kind of unsmooth surface had a good drag reduction effect for flow velocity ranging from 4m/s to 48m /s. And it had the best reducing ability (7.2%) at a velocity of 24 m/s. The theory of the drag reduction was finally analyzed.

By the Markov chain trigonometric grey prediction model(TGM(1,1)) was improved. At last, the validity and applicability of the model are demonstrated by a simulation of container throughput of Fujian Province.

A modified method to measure the similarity between the generalized fuzzy numbers based on Wasserstein distance is proposed. The method is more fully considered the difference of the generalized fuzzy numbers, especially the shape difference, by Wasserstein distance. The results of comparing the eighteen sets of generalized fuzzy numbers show that the method can overcome the drawbacks of the existing methods, and calculate the similarity measure excellently.

Tension reducing is one of the important processes in the production of steel tube, especially for the production of small diameter and thin-walled tube. Tension reducing mill has wide work speed range. A series of finished tube with different diameters and wall thickness were produced from a pierced billet by changing the velocity ratio between the rack. It is important to obtain the relationship of the wall thickness variation and tension for the production of satisfied steel tube. A speed calculation model was established for a suitable tension. The setting of the initial velocity field has great effects on the convergence of iteration process or iterations, so it must strictly satisfy the velocity boundary conditions, and must not break continuity condition and approximately meet the constancy of volume.

No 460 oil-film bearing oil as the dedicated lubricant is regarded as the incompressible Newtonian fluid. To comprehensively analyze the real oil flow state, the mathematical model on velocity profiles, together with its dimensionless equations, is established, and the calculating program is developed to simulate the 3D velocity profiles and velocity gradients at different oil flow layers. The relationship between velocity profiles and the oil film pressure is discussed, and the velocity tendency is consistent with the general velocity profile of wedge cross section. The conclusions are beneficial to the further study on lubricating performances of heavy contact components and to prolong their service lives.

Based on the theory of mathematical analysis, I find the rolling disturbance can be measured. Then the mathematical model of dynamic setting AGC is gotten by recursive methods. By the mathematical model I find out the influence of model parameters on the stability and convergence rate of the control system. When the system is stable, an influence of model parameters and parameter of the control system on steel strap thickness have been obtained, which will be helpful for us to choose suitable parameters in the end.

Owning to the unreasonable structural design of the rolling mill’s pressure screw, there is severe stress concentration on the top and the root of the screw thread, which make their abrasion seriously. Therefore the service life and accuracy of the pressure screw will decrease a lot. In the article, based on analysis of the structural parameters and material parameter of the pressure screw, we get the factors which will affect the contact stress between the screw thread. By the method, the contact stress between the screw thread is well-distributed, which will helpful for the designers