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Ultrasonic guided wave phased array technology is widely used in the damage detection of isotropic media, and its multi-mode problem leads to the complexity of signal processing, which affects the final imaging accuracy. In this paper, a single mode separation algorithm is constructed in the frequency wave number domain.. The single mode is stripped together with the phased array imaging method. Finally, the data fusion method is used to achieve the superposition of different modes. Firstly, according to the simulation results, the appropriate excitation frequency is selected to generate multi-mode Lamb wave, and the rectangular array is used to collect the signal in space-time domain. 3-D Fourier transform is used to transform the time-space domain signal into frequency wavenumber domain, and a 3-D window function is constructed to separate the A 0 and S 0 modal damage reflection waves. The signal is restored to space-time domain by three-dimensional inverse Fourier transform. Then, the CSM (Common Source Method) imaging algorithm in time domain and frequency wavenumber domain of phased array is combined to realize the damage imaging of single mode. Finally, the superposition results of two different modes are achieved by data fusion method. The results show that the result of modal superposition is better than that of the single mode imaging.

Interdigital transducer (IDT), it is widely used in structural health monitoring of large-scale projects, due to its excellent designability. However, for the implementation of structural health monitoring of large-scale complex projects, the existing conventional piezoelectric transducers have some shortcomings, such as poor flexibility, poor mechanical and electrical performance, while the flexible transducer based on polyvinylidene fluoride (PVDF) is difficult to achieve efficient actuating performance. Based on the multi-physical coupling theory, the electrode width, electrode spacing, substrate size and other parameters of IDT was optimized by piezoelectric module. The orientation and the interval of IDT was determined, so as to realize the excellent electromechanical conversion efficiency. Firstly, the annular Dielectric Elastomer Interdigital Transducer (DE-IDT) model with different electrode width, electrode spacing, substrate thickness and substrate size is constructed. Under the piezoelectric plate, the strain of different electrode width, electrode spacing, substrate thickness and substrate size is analyzed. According to the strain, the piezoelectric effect is judged, and the optimal size of DE-IDT is obtained on the basis. The azimuth and distance of DE-IDT are simulated to obtain the optimal actuating distance. The circular DE-IDT has good omnidirectional characteristics and the optimal electrode width, electrode spacing, substrate thickness and substrate size are determined.

In order to improve the recommendation accuracy in collaborative filtering, this paper introduces deep learning into the recommendation algorithm, and proposes a personalized recommendation model and algorithm under the deep learning mode. Firstly, the advantages and disadvantages of common algorithms are analyzed; then, the deep learning mode is constructed, and the deep learning is integrated into the recommendation algorithm step by step; finally, the simulation data are verified by cosine similarity and probability based recommendation method, and the results show that the two methods get almost the same score, and get better recommendation results, which can effectively improve the recommendation progress and quality.

Due to the difficulty of trigger automatic emotion processing, the automatic emotion regulation of anger and fear is unclear and to explore. Using a priming procedure and ERP analysis, the current study investigated the time course of automatic emotion regulation and difference between anger and fear. 46 participants were required to finish a word matching task to activate the processing of emotion regulation unconsciously, then to complete angry and fearful facial expression identify task. Subjective self-reports and ERP results verified that: (1) priming procedure could effectively evoke automatic emotion regulation; (2) N170, EPN and LPP components analysis supported that the automatic emotion regulation started at the early stage, continued to the middle stage, and dissolved at the late stage of emotion processing; (3) anger and fear are two difference emotions with same automatic emotion regulation mechanism but distinct emotion processing.

A robust control method for super-maneuver flight based on the adaptive observer has been designed in this paper to solve the uncertainty of aerodynamic parameter, external disturbance and model error. The discontinuous projection adaptive law is adopted in the fast and slow loops to online estimate the uncertainty of aerodynamic parameter. The external disturbance and model error are observed and compensated by the adaptive observer which designed by applying the adaptive law in the general observer, and then Lyapunov function is selected to analyze the stability of whole system to obtain final control signal. The digital simulation of super-maneuver flight proves that the controller can effectively resist interference caused by the uncertainty of aerodynamic parameter, external disturbance and model error, and enhance the robustness of the system.

For the problem that the airdrop of inner equipment coupled with the crosswind affects the flight safety and completion of the airdrop mission, a novel controller based on the L1 adaptive control was designed. State feedback control signals were produced by the optimal control and the matched reference model was determined. On this basis, we transformed the system nonlinearity into the matched and unmatched uncertainty of L1 control system. Combing with the outer loop PID control for lateral deviation, we completed the lateral flight control system. Simulation results show that the controllers have strong robustness and suppress the undesirable high frequency dynamics with high adaptive gain.

Growth environment and physiological indices of tropical flower is an important parameter to measure crop growth, while the conventional method has its own limitations. The design combines machine vision and Wifi / 3G technology to achieve a physiological detection system based on Internet of Things through a wireless sensor network environment information collection crop growth, growth of information and video images are processed through the video capture crop, thereby obtaining the measured target data, preliminary tests showed rationality and practicality of the system.

In this paper, the working principle and system components of ultrasonic flowmeter are briefly introduced In accordance with ultrasonic flowmeter applicated in YuLin gas field, comparing the transmission error of upper and lower streams measurement on this basis, the pre-Operation measurement error and actual flow test/ calibration are explored and analyzed, and for the better use of ultrasonic flowmeter, authors put forward their understanding and recommendations.

Based the experiment of gas-liquid two-phase flow in horizontal pipes, a lot of datas of pressure, pressure difference were analyzed statistically, obtained and summarized the characteristics of probability density function (PSD) and power spectral density function (PDF) on three flow regime: stratified flow, slug flow, annular flow. And compared characteristics of PSD and PDF on pressure, pressure difference signal of differential flow regime. It found that PSD and PDF can be used for flow pattern identification, then provides a new reference method for flow pattern identification.

By using the H.ň.Mаккавеев Method, Return Period Method, Bankfull Discharge Method and the Effective Sediment Transport Discharge Method to the hydrological data of Ba River, the bed-building discharge has been calculated and made as flow conditions of river model experiment. Finally, it was applied to the model experiment about Ba River and the results was compared with the one of balance riverbed from the normal river model experiment made by Northwest Water Conservancy Science Research Institute in 2001. The result shows that 6 years working life of the reservoir of Ba-river No.B rubber dam being regime channel is agreed with that of the prototype. It indicates furthermore that the bed-building discharge used in this river model experiment is correct, and the H.ň.Mаккавеев Method, Return Period Method, the LuoMinxun formula of Bankfull Discharge Method has a better applicability to calculate bed-building discharge for Ba River.

Routine dehydration can't be satisfied the practical demand because of the heavier, the higher salinity and the more seriously demulsification of oil. The factors affecting the desalting and dewatering during the ultrasonic pretreatment of crude oil were investigated, including electric field strength, ultrasonic frequency, field temperature, the settlement time, pulse time and working mode, etc. The contrasting results show that sound intensity, radiation time and frequency are the main factors, and the secondary factors are test temperature, working mode and settlement time. Some reasonable operation parameters for ultrasonic demulsification of heavy oil dehydration are determined. The process and technical parameters for the application of heavy oil dehydration by ultrasonic demulsification are provided.

Liquid holdup is one of the important parameters in the calculation of multiphase flow, annular flow is a common flow regime in the condensating natural gas pipeline. In this paper, based the momentum equation, combined with pig experimental data of gas-liquid two-phase annular flow in large-scale loop, calculated the theoretical liquid holdup. The calculated theoretical data and experimental date were compared and analyzed, the results showed that theory and experiment had a good agreement, thus the experimental and theoretical calculation methods on liquid holdup of gas-liquid two-phase annular flow phase were established.

In this paper, the reason of horizontal angle gross error occurring in a connecting traverse was discussed firstly. The relationships of coordinates between forward and backward direction calculation were derived and analyzed. Furthermore the utility of the method is investigated using the results of an example. Finally some suggestions to avoid gross error were proposed.

Theoretical backing of the similarity laws obtained from the dual dimensionless parameters of the bed-form classification diagram is given by solving the equations of similarity conditions that are obtained from the 1-dimensional equation of motion, the continuity equation, the bed deformation equation, and the formula of bed-load transport. Furthermore, a distorted model experiment was conducted to predict the bed variation during a flood in the Chubetsu River (a tributary of the Ishikari fiver in Hokkaido, Japan). The usefulness of the similarity laws of a distorted model was ascertained, and it was found that the maximum scour depth occurs during a recession of the flood hydrograph.

Though the conventional C-arm fluoroscope is used in bone surgeries for decades, two outstanding disadvantages remain. One is that it is not well adapted to the image-guided orthopaedic surgery procedures. Another is exposure of patients and surgeons in the radiation environment are harmful. At present, computer aided surgical navigation system is more and more used in surgery, but it is only connected to MRI ( magnetic resonance imaging ) or CT (computerised tomography ). This research addresses these issues. Using the C-arm and binocular spatial position system to navigate, with the help of the computer, is studied in our laboratory. The new system is called CASNC (Computer Aided Surgical Navigation system based on C-arm). As a special example, the position of determining distal interlocking of tibia or femoral intramedullary nail using the CASNC system is also a main point in this research. The position of the C-arm and patient are detected at the same time when a preoperative patient X-ray fluoroscope was taken, and transfer them to the computer. Then the system has to establish a correlation between preoperative image data and intraoperative patientpsilas position and surgical tools. At last, the deviation of the spatial position of the hole on the nail and surgical tools are shown on the monitor, and it illustrates correct position and orientation. This system not only can maximise the advantages of the conventional C-arm and accuracy of drilling, but also reduce surgeon and stuff in the operating theatre, especially patients suffering the X-ray radiation exposure.