Abstract:To solve the problem of high-speed data transmission to a computer through LVDS interface during high-speed data acquisition. Using Xilinx Artix-7 series model XC7A35T FPGA as the main control chip, and based on USB3.0 interface chip design from LVDS to USB3.0 high-speed data transmission interface. LVDS transceiver built-in FPGA is used to receive LVDS data and write it to USB3.0 control transmission chip after caching by DDR3 to complete high-speed data transmission from LVDS interface to USB3.0 interface. After the data transmission test, the system can transmit the data received by the LVDS interface to the upper computer of computer through USB3.0. In the actual transmission process, the rate is kept at 250MB/s, which has the characteristics of simple hardware design and fast transmission speed.

Abstract:In order to improve the accuracy of power consumption measurement error monitoring of intelligent metering device, a power consumption measurement error monitoring system of intelligent metering device based on data acquisition and return is designed. The system is divided into hardware design and software design. The hardware part consists of two parts: the sub station and the master station. The main station subsystem is the main station error monitoring machine, which mainly includes the main station working machine, peripheral equipment and other information equipment. The substation terminal is composed of power acquisition module, CT switching module and Pt switching module. Its main function is to realize the collection of power and energy meter information data of primary equipment. The software is mainly composed of communication network and database. The main station subsystem and the sub station subsystem realize the data information interaction during the data collection and return through the communication network, and set up the database server in the local terminal equipment and the measurement center respectively. The simulation results show that: the system performance indicators meet the requirements of power grid electricity metering regulations, can replace the manual field monitoring equipment, the error monitoring results are accurate and reliable, and the application effect is good.

Abstract:The purpose of this research was to change the problem of large quantification errors of the detected electric energy in the conventional technology and easy failure of AC charging piles. The method adopted was to design an AC charging pile error verification method with image recognition and constructed a new type of AC charging pile Error verification device, through the sudden change amount of the image difference, the electrical power change of the checked charging pile was detected, the residual selection similarity algorithm was used to compare the difference T(n) between the two frames, and the difference between the current frame f(n) and the previous frame f(n-1)was calculated. Value and the change of the graphic difference value between the previous frame f(n-1) and the previous frame f(n-2)was also calculated. The result was that through the above design, the verification error of the AC charging pile was reduced, and the average error was less than 5%. Therefore, the scheme of this study improved the verification accuracy.

Abstract:In order to solve the problem that the partition results obtained by using fuzzy clustering algorithm cannot be verified effectively in the modular design of the mechanical structure of cigarette vending machine, this paper proposes a method to verify the rationality of fuzzy clustering results based on kinematics and dynamics simulation data. Firstly, the original fuzzy clustering matrix is established according to the function, geometry and physical correlation of each part, and the original matrix is transformed into the fuzzy similarity matrix by the included Angle cosine formula. Then, the fuzzy equal-order matrices is obtained by using the transitive closure algorithm, and the dynamic clustering tree is formed by taking different thresholds from the fuzzy equal-order matrices. Finally, Adams software is used to simulate the kinematics and dynamics of the core module after fuzzy clustering, and the simulation results are used to judge whether the fuzzy clustering results are reasonable or not. The experiment shows that the fuzzy clustering results can be judged effectively by using the method presented in this paper.

Abstract:Drilog logging while drilling system is developed by CNOOC Oilfield Services Co., Ltd. (COSL) during the 12th Five Year Plan period. Due to the special high temperature and high pressure environment and the special connection mode between the instruments, a single-core bus is needed for the interconnection between the instruments. The single-core bus is used not only for power supply, but also for signal transmission. The mechanical drill collar shell of the instrument is connected as the system ground to realize the power supply and signal multiplexing. This paper focuses on the influence of the key device parameters of the single core tbus (tool bus) bus on the bus carrying capacity. It analyzes and studies the design and selection method of the key device parameters. A physical interface of power supply and signal coupling is designed. Through field experiments and 300 well tests, the results show that the physical interface design can effectively reduce the waveform distortion of the bus signal and improve the load capacity of the bus system.

Abstract:Aiming at the problem that the current fabric automatic opener can’t accurately identify the opener guide line under the complex fabric texture background, this paper designs a fabric texture feature classification system based on GoogleNet network of transfer learning and residual network of nontransfer learning. In this paper, the sample data set is divided into seven texture characteristics, such as dense pattern, a total of 1543 images, randomly selected 80% of the images as the training set, the remaining 20% of the images as the test set. Two different convolutional neural networks achieve 100% recognition accuracy in the existing data set, and in the subsequent system test, 300 samples are added, and the final recognition accuracy of the system reaches 98%. The experimental results show that the application of googlenet network and residual network to the analysis and classification of fabric texture characteristics is feasible, and the system based on this algorithm has practical value.

Abstract:Aiming at the problem of large commutation torque ripple of brushless direct current motor (BLDCM) under six-pulse drive mode, a torque ripple suppression algorithm based on finite set model predictive control (FCS-MPC) is designed. Firstly, the characteristics of non-commutation current are predicted. Then, the value function is used to select the best switch state of driving circuit to suppress the ripple of the non-commutation current. The experimental results show that, when using the torque ripple suppression algorithm designed in this paper, the torque ripple deviation ratio of BLDCM is 4.04% at high speed and 0.88% at low speed, which means that the algorithm designed in this paper has good commutation torque ripple suppression effect whether the motor is running at high speed or low speed.

Abstract:Aiming at the problem of low positioning accuracy of mixed sound source, a non iterative algorithm to complete cross spectral matrix is proposed, which uses the Hermitian characteristics of the cross-spectrum matrix without iteration and improves the computational efficiency without sacrificing positioning accuracy. This method first establishes a sparse model, and converts the source localization problem into a compressed sensing problem by constructing a redundant impulse response (RIR) matrix as a compressed sensing measurement matrix. Then, according to the spatial sparse correlation of multiple source direction vectors, a projection operator is introduced, and the root mean square error of azimuth is kept within 5% under the framework of compressed sensing. The simulation results in the uniform circular array (UCA) environment show that the algorithm has better estimation performance than the traditional algorithm.

Abstract:When multiple intelligent sensor nodes form a network, it will monitor the physical environment in detail and is widely used. However, the sensor powered by battery is irreplaceable. In order to use the battery energy efficiently and monitor the environment effectively for a long time, a partition stable routing protocol (psrp) based on heterogeneous network is designed. The protocol divides the network into three areas according to the energy of the nodes. The nodes in area 0 communicate directly with the base station, and the nodes in area 1 and 2 use cluster mechanism for data transmission. The selection of cluster head mainly considers the residual energy of nodes and the distance from the base station. The farther cluster heads use relay nodes to forward data to cluster heads. Finally, different evaluation schemes (such as location change of base station and variable energy of nodes) are used to evaluate psrp. The results show that the proposed protocol can efficiently utilize the energy of nodes, reduce the average energy consumption and increase the stability period of the network.

Abstract:Vehicle logo classification is one of the methods of vehicle recognition. Vehicle logo classification is widely used in the safety protection of government buildings, campus, roads and other places. Aiming at the vehicle logo classification, a Pin-SVM based on large margin distribution (LMD-Pin-SVM) is proposed. Firstly, the margin distribution is expressed with margin mean and margin variance. Then introducing the optimal margin distribution into Pin-SVM and the linear LMD-Pin-SVM is built. In addition, the linear LMD-Pin-SVM is extended to the nonlinear case with kernel trick. And the nonlinear LMD-Pin-SVM is applied to vehicle recognition. All experiments show that the proposed method is superior to the state-of-the-art methods in generalization performance. Our LMD-Pin-SVM can effectively suppress the adverse effects of noise on the classification model and improve the classification accuracy of different vehicle logo images.

Abstract:In the power system with wind farms, the uncertain parameters that affect the economic operation of the system often have the characteristics of random fluctuation, which is easy to cause information loss in the process of power flow optimization. In this paper, the wind speed and load of wind farm are taken as the research object, and the probability box theory is used to describe the uncertainty of wind farm parameters. Firstly, the probability box model of wind and load is established by using the drift interval of distribution function. Then the probability box equal reliability discretization is introduced into the optimization model with the minimum generation cost as the objective function, and the optimal power flow model based on probability box theory is constructed. Finally, the interior point method is used to solve the model to obtain the optimal power flow calculation results, and the effectiveness of the proposed method is verified by comparing with the Monte Carlo method. The calculation results of IEEE30 bus system show that the probability box method can not only describe the uncertainty of the system more comprehensively and solve the optimal power flow problem effectively, but also shorten the calculation time and make the operation more simple and effective.

Abstract:The mass flow controllers currently used generally have lag in response, which leads to lag control in the mass flow controller control, which leads to the failure of the calibration of the oil gas concentration detection alarm system verification and calibration device due to the inaccurate concentration of the prepared gas. Aiming at the problem of inaccurate gas concentration caused by the slow change of the controlled gas flow rate of the verification and calibration device of the oil and gas concentration detection and alarm system, this paper designs a verification and calibration of the oil and gas concentration detection and alarm system based on a mass flow controller with a first-order and pure lag model. The device adds a control lag compensation controller to the original mass flow controller model. Its function is to free the gas control from the lag interference, so that it can quickly and stably reach the specified accuracy. We first use Simulink simulation to simulate the first-order mass flow controller with pure hysteresis model to verify its functionality and performance. The result is that the flow error is 0.89%. Finally, we used the designed mass flow controller with the first-order plus pure lag model for actual testing, and the measured flow error was 0.56%. The results show that the mass flow controller based on the first-order plus pure delay model can reduce the influence of control delay.

Abstract:There is a risk of radiation exposure in the signal acquisition process of PET images. Under the premise of ensuring the image quality, it is necessary to reduce the tracer dosage as much as possible. But this will cause artifacts in the PET image and lower signal-to-noise ratio. We propose a conditional generative adversarial network (cGAN) based on multi-scale contextual information fusion, which is used to optimize PET image reconstruction to improve the image quality of PET images. By redesigning the skip connection of encoder-decoder network as generator, we proposes a skip connection based on multi-scale context information fusion, which enables the decoder to obtain richer semantic features from the encoder during the decoding process. We adopt the strategy of making the generator network learn the noise distribution of low-dose PET images, which reduces the learning difficulty of the network. The proposed network is evaluated in the low-dose PET dataset. The peak signal-to-noise ratio was 29.948 ± 4.062, the structural similarity index was 0.926 ± 0.030, and the normalized root mean square error was 0.395 ± 0.211. Compared with the traditional denoising algorithm Non-Local Mean (NLM) and block-matching 3D (BM3D) and two deep learning methods RED-CNN and cGAN (U-Net is the generator), the proposed network is superior to the above four methods.

Abstract:Aimed at solving the problem about obtaining pose information and calculating the theoretical center of solder joints for BGA images with missing solder joints in the task of BGA chip visual inspection，an improved point pattern matching algorithm was proposed after analyzing the deficiency of the existing point pattern matching algorithm. The algorithm establishes a solder joint distribution matrix model base on the arrangement of BGA solder joints, and uses the metric space to expand the grid, maps it to the image space through affine transformation, uses the grid as a clue to determine the matching relationship, and finally uses the point set registration to complete accurate calculation，get the pose information and the theoretical center of the solder joint. Through simulation experiments, it is proved that the method can adapt to the situation of missing solder joints. The position error is 1.6% and the accuracy is improved by 26.4% compared with the traditional method.

Abstract:Due to the different shapes of inner holes of many precision instrument parts, a fast template matching method based on the improved regular edges is proposed, aiming at the quality inspection for inner holes of regular edge parts. By performing mathematical morphology and least squares edge fitting on the acquired part image, the region of interest (ROI) containing only inner holes of parts is extracted, and finally the matching detection of modeling on inner holes of parts is completed. By verifying the accuracy and speed of the proposed algorithm, experiment shows that this algorithm can meet the industrial inspection requirements of parts, the accuracy is 8.9% higher than that of the traditional template detection algorithm, and the detection time is 0.72S faster than the traditional template detection algorithm.

Abstract:Aiming at the problem that the binocular ranging technology has a large error in long-range ranging applications, this paper proposes a long-range binocular ranging method based on perspective transformation. First use the camera's internal and external parameters obtained from the calibration to perform stereo calibration on the distorted image. Use template matching to obtain the world coordinates of the four pairs of feature points and the distance of the selected baseline. The triangulation method calculates the distance between the target object and the camera. The experimental results show that when the object to be measured is 10m or more away from the camera, the traditional binocular ranging method has a large measurement error or even cannot be measured, and the perspective transformation method proposed in this paper measures when the object is 45m away from the camera. The error can still be guaranteed between 3% -5%, and the accuracy is high. Therefore, this method can effectively solve the problem of large error of binocular ranging technology in long-range ranging applications, and has certain practicability.

Abstract:Aiming at the blind spot of on-line fault monitoring of photoelectric tracking equipment, the cable signal transmission fault detection method is studied. In this paper, the cable detection is based on the principle of impedance mismatch at the fault location, and on the basis of the reflection method, a design with strong anti-interference and no communication influence and good correlation with the test signal, using the signal generator and the data acquisition system to inject the signal and collect the reflected signal, and eliminating the cross term caused by the signal superposition of the collected signal, and finally determining the cable fault location and fault type by the correlation analysis of test signal and the collected signal , and obtaining the fault unit of the equipment. Verifying the detection performance, stability and engineering practicability of this method by comparing performance with the spread spectrum time domain reflectance method.

Abstract:Si3N4 acts as both passivation isolation layer and infrared absorber layer in infrared thermopiles, and its thin film etching is crucial in the MEMS process. The RIE-10NR reactive ion etcher was used to etch the silicon nitride film by varying the oxygen flow rate, RF power, and chamber pressure using SF6 as the main etching gas. The etching rate and etching uniformity were characterized by step meter and confocal microscope. The experiments showed that the etching rate of silicon nitride reached 509 nm/min with a non-uniformity of 2.4 % under the conditions of 50 sccm SF6 flow rate, 10 sccm O2 flow rate, 11 Pa chamber pressure and 250 W RF power, and the etching rate of polysilicon reached 94.5 nm/min with a selection ratio of 5.39:1 under the same conditions.

Abstract:In order to reduce the impact of external vibrations and shocks on the output accuracy of the micro inertial measurement unit (MIMU), combining the requirements of MEMS sensor support and multi-degree-of-freedom vibration reduction theory, a suitable damper placement method was selected and a MIMU rubber vibration damping system was designed. The MIMU structure has the characteristics of light weight and small volume, and has sufficient rigidity to ensure the stability of the structure, and the setting of the rubber shock absorber effectively reduces the vibration coupling. In order to accurately describe the rubber properties, the Mooney-Rivlion constitutive model is used to simulate the rubber material, and the parameters of the vibration-damping rubber material are determined according to the empirical formula. The actual shape finite element model of the vibration reduction system was established, and the dynamic characteristics analysis was carried out. It is obtained that the first 10 natural frequencies of the system were far away from the external excitation. Considering the large deformation of rubber, the deformation Angle of the circuit board in the vibration damping system is taken as the evaluation criterion in the transient response analysis. The results show that the deformation Angle of the circuit board is 0.06°, which meets the design standard, and has a good vibration reduction effect compared with the MIMU without vibration reduction.

Abstract:Aiming at the problem of mixed assembly of parts in the production process of enterprises, the background separation algorithm based on Gaussian mixture model is designed to achieve stable and flexible background separation effect. The feature extraction algorithm based on gray level, similar shape and simple contour is used to achieve effective and stable feature data extraction effect. The multi-layer neural network algorithm based on XML data storage is used to realize the background separation effect The effect of dynamic change of item type. Through the image separation, extraction, recognition, to achieve the effect of classification, the results show that the system can not only achieve the stable and intelligent classification and recognition effect of industrial environment, but also ensure more than 99% of the high classification accuracy at the same time, quickly complete the classification task, and provide a simple and effective solution for the demand of market diversification.

Abstract:Aiming at the accidental abnormal operation of Beidou in an underwater vehicle, an independent real-time monitoring system of Beidou status is designed, which continuously measures and calculates the relevant parameters of the current Beidou status of the vehicle, and carries out temporary intervention control according to the relevant judgment criteria, so as to improve the efficiency of Beidou communication and positioning, so as to improve the navigation performance of the vehicle Safety and reliability. In the design of the system, the internal structure and working environment of the vehicle are fully considered. On the basis of considering the original bus protocol, control conditions and control flow and other related requirements, the commonly used large-size and high-power components such as isolation and switch are abandoned, and the small-size and low-power integrated design scheme is adopted to realize the real-time monitoring function of the Beidou state of an underwater vehicle. The monitoring system has passed the environmental test and electromagnetic compatibility test, and carried a certain type of underwater vehicle in a domestic water area to complete the actual navigation test. The test results show that the monitoring system can intervene in the control when the Beidou of the vehicle is abnormal, and improve the navigation safety and reliability of the vehicle.

Abstract:An automatic unloading device for docking drones is designed based on an intelligent logistics system for drones. Compared to the large assembly lines and complex robotic unloading devices under existing technology, the mechanism is characterised by a simple structure, easy disassembly and reliable operation. According to the work requirements of the force analysis of the mechanism, ADAMS to establish automatic unloading device virtual prototype model and its dynamics and kinematics simulation, to derive the trajectory of the cabin components and movement parameters, according to the characteristics of its movement to its design, to provide a basis for its final design, laying the theoretical foundation for the automated design of the UAV intelligent logistics system.

Abstract:In order to solve the problems of low sensitivity and narrow linear range of fluorescence immunoassay, an immune analyzer based on immunochromatography assay and time-resolved fluorescence microparticles was designed. In the system, the detection object is the fluorescent reagent card, the marker of which is the time-resolved fluorescence microparticles. The excitation light is monochromatic LED (340 nm). The fluorescence emitted by the fluorescence microparticles on the T line and C line of the reagent card is detected by photodiode. The concentration of the measured substance can be calculated using the fluorescence value together with the standard concentration curve. The results show that the immune analyzer shows up good linearity in the range of 0.5~200mg/mL, with linear correlation coefficient R2=0.9988. The precision of the immune analyzer is also pretty good since the instrument CV is generally less than 1%, and the inter-instrument CV is no more than 2.5%. The merit of simple operation and fast detection allows the immune analyzer to be applied in a wide range of fields, such as the POCT, drug detection, food safety detection and so on.

Abstract:This paper designs a multi-axis manipulator control system for automatic sampling analyzer. The system is mainly composed of microcontroller, three-axis manipulator, positioning sensor, liquid crystal display, communication module and other parts.The microcontroller can control the movement of the manipulator by receiving the instruction of the host computer.The manipulator module adopts a control strategy of multi-axis cooperative movement, which can correct the control parameters in real time and optimize the motion trajectory to ensure the precision, stability and speed of the manipulator's moving process.For some community hospitals and other basic medical institutions, considering its economic, demand and other factors, it is of great significance to develop a small automatic sample adding analyzer with high precision, high stability and low cost. After the experimental test of the system, the multi-axis manipulator control system designed in this paper can meet the requirements of equipment testing in small and medium-sized hospitals.

Abstract:The most basic part of FAIMS system is the high field asymmetric RF power supply, which provides voltage difference for the effective separation of ions in the migration region. In this paper, the principle of half bridge inverter is used to generate RF square wave. A three leg square wave generator is designed to reduce the current flowing through the high voltage DC power supply. So the power of the system is reduced effectively. Considering the complexity of FAIMS chip and the portability of the instrument, the differential RF mode is improved, which effectively reduces the input requirements of FAIMS for the high voltage DC power supply and is beneficial to the high voltage DC power supply. It is beneficial to simplify the high-voltage DC power supply and reduce the power consumption, which is conducive to the miniaturization of FAIMS. Combined with automatic scanning of compensation voltage, the optimized high field asymmetric rectangular waveform RF power supply is developed. Through experimental comparison, it meets the requirements of FAIMS migration area.

Abstract:a novel coronavirus pneumonia monitoring system was designed for monitoring the temperature of the COVID-19 with a centralized isolation population. It also applies to scenes requiring continuous monitoring of body temperature and common use.The design was based on MCU,the temperature acquisition module collected the wrist surface temperature and the external environment temperature respectively, compensated the influence of the environment temperature on the wrist temperature by the least square fitting method, and then transmited to the mobile phone through the Bluetooth module. The mobile terminal could display the body temperature value in real time. When the temperature was abnormal, it could display the abnormal reminder and view the historical temperature data. After testing, the measurement error of the system is less than 0.1 ℃, and it has good stability, high real-time performance, good visual effect and easy function expansion.

Abstract:In order to realize the intelligent control and system self-test of automatic weather station, a wireless communication system with self-test function is designed. The system uses RS232 serial port communication and GPRS wireless communication to connect a variety of meteorological signals to the automatic weather station through the bus interface. The ground equipment collects the element signals of the weather station according to the communication protocol. After completing various operations, the collected meteorological data is transmitted to the upper layer for terminal processing. The system measures the main meteorological elements through five self inspection measuring points, and the results are as follows: the five measured values of temperature are - 2.5OC, 12.2OC, 23.3OC, 28.6OCand 33.4OCrespectively, and the maximum error is 1.2%; the five measured values of humidity are 10.0%, 20.0%, 30.0%, 40.0% and 50.0%, and the error is 0; the five measured values of rainfall are 0.2mm, 0.3mm, 0.4mm, 0.5mm and 1mm respectively, and the error is 0; the five measured values of wind speed are 0 The measured values are 1.9m/s, 3.1m/s, 4.2m/s, 5.3m/s and 7.4 m/s respectively, and the maximum error is 4.5%, and the above measurement errors meet the requirements of meteorological observation specifications. The results show that the system can transmit the collected meteorological data to the upper layer for terminal processing, and realize the self-test function. When the equipment fault is found in the self-test, it will automatically alarm and remind, and push it to the business management personnel in real time, so as to shorten the fault response time, realize the intelligent control of the weather station, and improve the observation quality of the business data of the automatic weather station.

Abstract:Interwire crosstalk is easy to occur due to numerous cables and long and narrow wiring space of EMU.By introducing the wiring situation under the vehicle and combining with the theory of crosstalk, a shielding protection scheme to reduce the crosstalk between cables is designed.In the CST cable studio, the cable simulation model was established under two different working conditions of M car and T car, and the crosstalk current and voltage in the sensor cable were obtained.Through simulation waveform comparison, the current and voltage after the installation of shielding are significantly reduced compared with the crosstalk before the installation of shielding, which conforms to the error range of the normal operation of the equipment, and verifies the effectiveness of the scheme.At the same time, it has certain engineering reference value to the layout and wiring of other types of electric locomotives.

Abstract:A Source Meter has been designed, which is based on ARM Cortex-M4. The output of voltage and current source is implemented by the AD5422, and the output accuracy is 5 digits in the range of 0-10V and 0-20mA,the error is within 0.02%.. The measurement functions of voltage, current, and resistance are realized by LTC2440, and the measurement accuracy reaches six and a half digits,the voltage measurement error is less than 0.003%. The measurement of the signal is sampled by ADC, which is amplified by strobe, the sliding mean filter method has been used to filter the sampling disturbance, and the least square method is used to calibrate the data. The measurement and output data are displayed on the LCD. The digital source meter has low cost, high digital integration and easy operation, which is suitable for being widely used in the undergraduate teaching experiment of electronic information.

Abstract:In view of the difficulty of water quality monitoring and regulation in aquaculture industry, a water quality monitoring unmanned vehicle system is designed and developed by using NB-IOT technology, which can realize autonomous cruise collection of water quality and real-time monitoring and regulation of water quality in the cloud platform. The integrated navigation of digital compass, BD-GPS and IMU is used to realize the autonomous cruise and motion data acquisition of the unmanned vehicle. During the navigation, the water quality data is collected by pH, turbidity and dissolved oxygen sensors, and then the water quality and motion data are uploaded to the OneNET cloud platform through NB-IOT module. Taking dissolved oxygen regulation as an example, the water quality regulation node is designed to receive the cloud platform instructions to control the aerator, so as to achieve dissolved oxygen regulation. The experimental results show that the system can achieve the design goals and requirements well. In the cloud platform, the system can observe the water quality and movement information in real time, and issue instructions to control the aerator to adjust the dissolved oxygen content. After 25 minutes of remote opening, the dissolved oxygen content increases by 0.11mg/L. The system inspects 9 target points of a pond with an area of about 1 hectare, the average time is within 5 minutes, and shows good performance.