bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on a Design Algorithm of Dynamic Spectrum Access Criterion
Authors: Teng Xiaoyun , Xie Jun , Dai Xuefeng
Published: October 2020

In order to improve the utilization of electromagnetic spectrum, electronic devices can sense the current spectrum occupancy status and use these spectrum resources without disturbing the communication of other authorized users. In the past research, researchers have generally ignored the randomness of the propagation channel and the uncertainty of the location of the authorized user on the spectrum perception. To this end, this paper proposes a dynamic spectral access criterion design algorithm.
Study on probability of ship impact against bridge out of control
Authors: Liu Yanli , Li Bing , Lv Jinhua
Published: October 2020

Ship collision accidents happen occasionally, many of which are caused by ship out of control. At present, there are few studies on the probability of collision of ships with bridges out of control at home and abroad, and no mature results have been formed in all aspects of the research on the accident of collision of ships with bridges, which need further study. In this paper, the influence of wind and flow is analyzed, the drift model of wind and flow is established, and the probability of collision of out of control ships with bridges is calculated, so as to provide technical support for safe navigation of ships and anti-collision design of piers
A Design of High Power Beidou L-Band Power Amplifier
Authors: Xue Xiaogang , Wang Xiaoyu , Luo Sang , Li Rui , Yang Jian
Published: October 2020

According to the optimization problem of power amplifier output power, linearity and other performance indicators, this paper proposes an improved three-level cascade overall design framework, designed by the load traction method, source traction method and power back-off method for the driver stage and final stage power. The amplifier better improves the output power and linearity of the system and the high-gain pre-stage power amplifier is designed by the small-signal S-parameter method. After the performance analysis, simulation design, physical production and testing of the cascaded power amplifier, the output power of the system is 15W. This paper implements high power, high gain, high linearity power amplifier design, and applies this result to BeiDou Navigation Satellite System (BDS).
Communication Control System of UAV Based On 5G Network
Authors: Liu Jinchang , Wu Xiaoou , Fu Ning , Pang Hui , Ma Zhonggang , Yang Jiangmin
Published: October 2020

Remote control is the traditional control mode of unmanned aerial vehicle (UAV), which limits the signal transmission distance. To accomplish ultra-long-distance UAV control, we propose a communication control system which based on 5G network to transmit UAV control signals. We develop a backstage service platform based on 5G network to connect with the communication module installed on the remote UAV. In this paper, we describe the detail of this system which realizes the normal communication control of the remote UAV and the service platform. Our experiment results show that our system has the characteristics of stability and scalability.
Automatic UAV Relay Communication System Based on Microwave Directional Antenna
Authors: Liu Jinchang , Zhang Lili , Gao Ping , Ma Jun , Xia Chuanfu , Lin Renjie
Published: October 2020

To tackle the communication problem of unmanned aerial vehicle (UAV) complex aerial operations, we propose an automatic UAV relay communication system based on microwave directional antenna. Our system is organized by the design scheme, overall structure and working process. The system has the ability to transmit information at a distance, which solves the problem of limited communication distance caused by the transmission power limitation of UAV communication system. The system can automatically switch into different communication mode according to communication network environments to improve the communication quality. In addition, it increases the mobility and enhances endurance in severe environment to meet the emergency communication covered on demand.
Parametric Design on Solving the Maximum Deformation of Traction Helical Gear on Locomotive
Authors: Ding Haichun , Lei Lei , Qin Meichao , Wang Guang
Published: October 2020

The helical gear for locomotive traction has a popular application in the locomotive transmission system due to its excellent transmission performance. The maximum amount of deformation needs to be taken into consideration when performing the tooth profile modification on helical gear. The tooth profile design and corresponding calculation process tend to be tedious since the variation of the contact ratio of gear might lead to the change of logarithm in meshing tooth. In this paper, starting from the effect of the contact ratio on the logarithm of meshing teeth, the mesh-stiffness of helical gear can be solved by cross-section deformation formula based on the similarity of helical gear and spur gear. And then the general calculation formula governing the variation on the length of contact line is derived regarding the moment when gear tooth just engages. On the basis of actual production requirements, the solution equation for inter-tooth load distribution coefficient is derived. As a result, the general mathematical model for maximum deformation of helical gear which can perform parameterized calculation is established. The theory provides a significant theoretical guide in the field of tooth profile modification on locomotive traction helical gear.
Design and Analysis of High Birefringence Photonic Crystal Fiber with Sandwich Structure
Authors: Liang Ruoyu , Zhao Haiying , Zhao Lijuan , Li Xingrong
Published: October 2020

A novel photonic crystal fiber (PCF) with sandwich structure in cross section is proposed. Then the influences of the size of air holes in cladding on the propagation properties are investigated. By adjusting the size of air holes in cladding, the proposed PCF offers an ultrahigh birefringence of 3.85 × 10-2 and a large negative dispersion of - 1000 ps·km-1·nm-1 for the optimal structure of the fiber at the wavelength of 1550nm. The nonlinear coefficient of the optimal structure can reach a large value about 50W-1 ·km-1 at the wavelength of 1550nm. The proposed PCF may have some potential applications in the fields of long-distance optical communication and polarization maintaining fiber.
Design of ACC Adaptive Cruise System Based on Ultrasonic Ranging and Internet of Vehicles
Authors: Sun Xinyu
Published: October 2020

Nowadays, with the development of society, the vehicle ownership continues to increase. Vehicle has become the third important space for people besides home and office. As an important means of transportation for daily travel, people pay more and more attention to the convenience and safety of vehicle control. However, most vehicles sold on the market today are not equipped with emergency braking or emergency avoidance systems, even if equipped with the system, its accuracy is not high enough. When an emergency situation occurs in front of the vehicle, the vehicle cannot evade or brake on its own, only the driver can take measures, which often causes unnecessary collision. An ACC adaptive cruise system using ultrasonic ranging and Internet of Vehicles can share driving information between vehicles via Bluetooth to ensure identification of the speed and accuracy of the front vehicle, and able to avoid the front vehicle without driver’s intervention, enhancing emergency response capabilities. At the same time, unlike the existing ACC adaptive cruise system, most of which can only be activated when the speed is higher than 25km/h or 30km/h. This system can work at full speed of the vehicle, automatically follow the front vehicle, and automatically brake or accelerate reverse, increasing the convenience of daily driving.
Welding Seam Detection and Tracking Based on Laser Vision for Robotic Arc Welding
Authors: Yin Ziqiang , Ma Xinqiang , Zhen Xiao , Li Wenlong , Cheng Wei
Published: October 2020

The welding robots are widely employed in the manufacturing field. In order to measure up to the developing need of automation and intelligent production, real-time welding process sensing and controlling are necessary, in which the welding seam detection and tracking is representative task. Among the kinds of sensors applied in the robotic welding process, vision sensors is one of the most widely used for automatic welding seam tracking and quality control in robotic arc welding. This paper is to present a new framework and the data process algorithm of the sensor. A novel two-step calibration approach is proposed in this paper based on the “Calibration toolbox in Matlab”, the proposed approach acquires the laser light plane by project the linear stripe on the calibration pattern plate during camera calibration process. Experiment result indicates that the fitting error of the detected 3D point data of the weld groove is less than 0.1mm. The tracking error in robotic welding process is no more than 0.2mm. Which is acceptable for robotic welding system.
Gyroscope Fault Pattern Recognition Based on Wavelet Packet Decomposition and Fuzzy Clustering
Authors: Liu Zhaozheng , Xiao Mingqing , Zhu Haizhen , Li Jianfeng
Published: October 2020

Aiming at the problem that the sensor component’s inertial navigation gyro failure symptom is not obvious in a certain aircraft flight control system, this paper proposes a fault cluster recognition method based on fuzzy clustering. First, use wavelet packet decomposition to perform three-layer wavelet packet decomposition on the gyro output data to obtain the feature extraction of the gyro fault signal; then use the fuzzy clustering method to classify the extracted fault signal to achieve gyro fault pattern recognition in the sensor assembly the goal of.
Collaborative Filtering Based on a New Matrix Factorization Algorithm
Authors: Yan Yongjie , Xie Hui
Published: October 2020

Online platforms such as Facebook, Netflix, and Amazon, provide users with information on products or services that matches their interests or backgrounds. As one of the most popular services over online platforms, recommendation system has attracted increasing research efforts recently. Among all the recommendation tasks, an important one is item recommendation over high spectral data. Existing recommendation techniques are not effective for handling users with diverse interests. In this paper, the sparsity problem of traditional recommendation algorithms, a new recommendation algorithm based on spectral clustering is proposed. The spectral clustering process can improve the efficiency of spectral clustering algorithm. Spectral clustering can be performed off-line, which will accelerate the speed of online recommendation. The experimental results on Netflix show that the new algorithm improves recommendation quality in MAE and coverage.
Fall Detection Monitoring System Based on MEMS Sensor
Authors: Wu Youyu , Xiao Yiyao , Ge Hua
Published: October 2020

In order to get timely treatment after the elderly fall, this paper proposes a wearable device to monitor the fall of the elderly. The device includes a data acquisition module, a data processing module, and a wireless communication module. With the elderly wear the device at the waist, the human body posture data will be collected by data acquisition module, and will be processed by data processing module, and combines the random forest algorithm to distinguish between daily activities and fall behaviors. When the fall occurs, the device alarms by sound and light. At the same time, the transparent cloud platform matched with the wireless communication module can monitor the position and status of the elderly in real time. When a fall occurs, the emergency contact will be notified through WeChat and email, and the real-time alarm will be realized, and the old man will get timely treatment after the fall.
The Necessity of Testing the Optical Fiber Link in the Distributed Control System
Authors: Zhang Fang , Zhang Li , Yang Jinlin
Published: October 2020

With the rise of industry 4.0 and the Internet, a large number of network optical fiber links are applied in the control system of thermal power plants. However, there are no test methods and requirements for optical fiber links in the acceptance test procedures for decentralized control system of thermal power plants. In this paper, the optical fiber medium, field bus type and so on are introduced, and the necessity and method of optical fiber link testing are discussed.
The Control Strategy Research of 4WID Vehicles Steering-by-Wire System
Authors: Wang Yao , Cheng Qingzhang , Gao Linlin , Zhang Wenjun
Published: October 2020

Once the traditional electric vehicle was refitted with distributed drive (4wid) system, the increasing of vehicle’s unsprung mass would significantly increase the steering resistance, as a result of that, the efficiency and accuracy of the original car’s steer-by-wire (SBW) system will be reduced. In order to solve this problem, taking BAIC-EV150 for example, this paper introduced a design of SBW control strategy for 4WID vehicles, and the corresponding refitting work of real vehicle were completed. The refitted vehicle adopted dual-motor, dual-controller to coordinate control the output torque, aiming at compensating the resistance moment. Simulation and experimental results show that the controller can meet the requirements of 4WID vehicle steering, and the dual-motor steering system based on fuzzy PID control is more responsive and more accurate than the single-motor steering system which under ordinary PID control.
Analysis and Application of Indoor Fire Fighting Positioning Technology Based on Inertial Navigation
Authors: Deng Jun , Zhao Jiaxiang , Wang Weifeng , Sheng Youjie
Published: October 2020

In recent years, all kinds of complex buildings have increased rapidly, and the difficulty of fire rescue has increased significantly. Therefore, it is of great significance to improve the level of fire rescue to study the precise positioning technology that can be applied to the firefighter’s room in all kinds of complex scenes. In this paper, several common indoor positioning technologies are summarized and introduced, and their positioning principles, positioning accuracy, use scenarios and other parameters are analyzed by analogy. The application of inertial navigation positioning technology in the positioning of firefighters in complex indoor environment is discussed and verified by experiments. According to the analysis results, the key technologies for the indoor positioning of firefighters are optimized. The analysis and research in this paper can provide theoretical support for improving the positioning of firefighters in the room.
A Study on Thermal Stability of Star-Sensitive Brackets Made Up of Different Material Based on Precision Measurement
Authors: Ruan Guowei , Wang Ziwen , Long Changyu , Zhang Yuhang
Published: October 2020

Aiming at the installation requirements of a certain type of spacecraft involving star sensitivity, the research and development of aluminium alloy star sensitive bracket, titanium alloy star sensitive bracket, composite material star sensitive bracket and 3D printed star sensitive bracket have been completed. The simulation study of thermal stability is given. In order to investigate the actual thermal stability performance of the star-sensitive bracket, to quantify the thermal deformation characteristics of the star-sensitive bracket under the overall temperature condition, a measurement scheme combining photogrammetry and theodolite measurement is used to conduct a thermal stability test and deformation test. The test proves the feasibility of the measurement scheme and provides some data support for the improvement of the star-sensitive support structure.
Research on Evaluation Indexes of Low-Carbon Environmental Protection Living Supply Chain
Authors: Liu Shiming
Published: October 2020

In the process of implementing a low-carbon living supply chain, the results we seek also need to be evaluated. This is a very critical step. Correct and reasonable evaluation can help us find problems and find solutions to problems. This will improve the operation of our green supply chain. Practice a low-carbon lifestyle and create a happy life.
Cone Sleeve Center Measurement Algorithm based on Multi-information Integration
Authors: Shi Bowen , Zhang Jingyu , Yang Shoubo
Published: October 2020

In order to meet the high-precision docking requirements of autonomous aerial refueling, this paper proposes a high-precision and fast positioning algorithm for the center of the cone sleeve based on two-dimensional and three-dimensional multi-information fusion. The algorithm performs target detection and tracking on the cone sleeve in the image after calibration and calibration, and adaptively selects the region of interest in the positioning area; the region of interest is calibrated based on the gray-scale constrained two-dimensional model and the three-dimensional model based on the depth gradient. The two-dimensional and three-dimensional information fusion result is back-projected and compensated to the region of interest to realize the high-precision center point position measurement of the center point. The algorithm is used in the semi-physical simulation experiment on the ABB mechanical arm to verify its feasibility, robustness, fast and high precision and other characteristics.
Research of Acoustic Emission Health Monitoring Test of Plane Welding Joint
Authors: Zhang Haibing , Wang Yongqi , Zhu Longxiang
Published: October 2020

The welding joint is the key area of Aircraft bearing structure, which is not only subjected to alternating fatigue force, but also to the impact force during takeoff and landing. In this paper, the formation model of fatigue crack is studied, and the health monitoring of aircraft welds based on optical fiber acoustic emission technology is proposed in combination with the principle of acoustic emission detection. The sensor arrangement scheme and test conclusion are given through the actual acoustic emission test of simulated damage of welding joint, which provides the basis for the health monitoring of welding joint of aircraft in service.
Design and research of computer room communication system based on electronic information technology
Authors: Luo Jiachun , Yuan Ming , Lai Zhuocheng , Sun Yong , Chen Tianyu
Published: October 2020

No new building can be built without the computer room. The computer room is just like the soul of the information system. The construction of any large-scale information system is inseparable from the support of network, host and other communication equipment. This paper studies the optimization of the whole communication system. From the five aspects of practicality and advanced nature, safety and reliability, standardization, flexibility and extensibility, and manageability, the paper introduces the principles of building the communication system of electronic information room, and forms a complete set of communication system design for electronic information room. At present, serial communication is commonly used in electronic information communication system. The communication mode is half duplex communication of fd-mac layer protocol to improve the communication throughput. It is suitable for communication in electronic information room because of its fast transmission speed and space saving.
Implementation of B2a Code Generator of Beidou-3 Satellite Based on FPGA
Authors: Zang Zhibin , Xia Chuanfu , Wu Xiaoou , Ma Jun , Fu Ning
Published: October 2020

In the satellite signal acquisition and tracking, the locally reproducible ranging code plays an important role. For the newly launched Beidou-3 satellite in China, a method for implementing the B2a signal ranging code generator in FPGA is proposed. Taking the B2a ranging code of Beidou-3 satellite as the research object, the design principle of the B2a ranging code generator is explained in detail, which includes the analysis of the key modules of the Weil code and the Gold code generator. The FPGA is modularly designed to be scalable The B2a ranging code generator module, through the reserved register initialization interface, can realize the ranging code of different PRN satellites, solving the complex problem of generating arbitrary satellite number ranging codes, for the design of Beidou No. 3 navigation receiver Certain reference significance.
Auxiliary sit-up device with adjustable motion trajectory based on conversion movement of sitting and standing
Authors: Zhou Jie , Liu Kaijie , Li Xinyu , Li Lu , Zhang Chenyu
Published: October 2020

The device takes the elderly as a service object, and proposes a device for assisting the elderly to get up and down. The device realizes a series of processes for the elderly from lying on the bed to sitting up, and then from sitting to standing. And can provide some assistance through the reverse operation of the device when the elderly need to lie down. The overall operation process of the device is simple, and it solves the problem of getting up and getting out of bed due to insufficient waist and arm strength of the elderly at present.
Design Manual of Portable Intelligent Medicine Box
Authors: Han Peisong , Jiang Keyue , Peng Yucheng
Published: October 2020

The device takes the elderly living alone with chronic diseases as the application object and provides a novel portable intelligent medicine box. The device realizes medicine storage and taking out through simple mechanism combination innovation, and realizes functions of timing reminding, light reminding, taking records and the like through the design of a control part. The device is designed by adaptive size, which can adapt to the palm size of most old people. Moreover, the operation flow is simple, the difficulty of taking medicine for the elderly living alone is reduced, and the safety of taking medicine for the elderly living alone is ensured. On the premise of complying with national standards, the device has superior performance, complete functions, low cost and high use value, and has a broad market prospect.
Optimal Design of Barrel Based on Selective Laser Melting
Authors: He Lijun , Fu Quan , Li Yi , Liu Zhangqian , Zhang Zhixiong
Published: October 2020

Selective Laser Melting (SLM) is an additive manufacturing technology based on melting layers of metal powder using powerful laser without traditional limits. SLM makes it possible to manufacture complex structures such as enclosed inner cavity and complex surface. However, most of the mechanical parts are designed according to the requirements of traditional processing technology. There is often material redundancy in these parts, which will seriously affect the speed of SLM printing and increase the cost of SLM printing. In this article, according to the actual working condition, the barrel of a grenade cartridge based on traditional process design was optimized using a method of interior lattice structure to achieve the goal of lightweight, to eliminate material redundancy as much as possible. Then the strength and printability of the optimized parts were verified.
Design and analysis of permanent magnet biased radial magnetic bearing with external rotor for vacuum tube
Authors: Wang Ying , Mei Lei
Published: October 2020

A permanent magnet biased radial magnetic bearing with external rotor for vacuum tube was introduced, and the configuration and operating principle were analyzed. The parameter design method based on the total magnetic flux was established to deduce the calculation formulas of the parameters of the permanent magnet radial magnetic bearing. The magnetic flux leakage coefficient and the magnetic resistance coefficient were considered, and the calculations were constrained to the degree of magnetic flux density unsaturation of the internal magnetic field of the soft magnetic material. Finite element software was used to execute simulation analysis and modeling of the permanent magnet biased radial magnetic bearing. The results show that the design method is reasonable and efficient, and the design magnetic bearing is compact and easy to control, which is more suitable for the liner motion with low power consumption.
The design of permanent magnet variable-frequency door-motor with one-driver dual control
Authors: Tang Xiaozhou , Ye Jian , Zhang Liping , Yao Yunfeng , Shao Peng
Published: October 2020

Aiming at the scarcity for matched high-end door-motor to domestic high-velocity elevator market, with the research on domestic and overseas elevator door-motor control technology and permanent magnet synchronization technology, a high-end door-motor system that matched with high-velocity elevator and even ultra-high-velocity elevator has been put forward. It introduced in detail about the door-motor control hardware design that used digital chips and intelligent power module as its main circuit, how to realize the door-motor operation curve with SVPWM (Space Vector Pulse Width Modulation), the orientation angle learning method of permanent magnet synchronization motor, how to work in parallel for dual-motor and how to switch the single motor as well as the overall mechanical design scheme. The actual door-motor operation curve has been surveyed through experiment and the operation curve has been analyzed. The research results indicate that the door-motor system can suffice the design requirements input and the design scheme is reasonable and reliable, which will not only significantly shorten the opening and closing time compared to the ordinary door-motor and distinctly improve the service efficiency of high-velocity elevator, but also make the operation curve of the door-motor more graceful, quieter, more stable and safer.
Predictive Control of Five-leg Inverter-Double Permanent Magnet Synchronous Motor System with Error Feedback Model
Authors: Chen Chen , Xiao Xiong , Sun Qianli , Peng Minghua , Wu Jianlei
Published: October 2020

In this paper, the five-leg inverter-dual permanent magnet synchronous motor system is taken as the research object. To solve the problem of large steady-state speed fluctuation when applying the traditional model predictive control strategy, based on the mathematical models of the five-leg inverter and the dual permanent magnet synchronous motor, the causes of the fluctuation are analyzed, and then an improved model predictive control algorithm with error feedback is proposed. The algorithm makes full use of the high-speed operation ability of modern digital processor, and introduces the prediction value of error feedback correction model, so that the rolling optimization is not only based on the model, but also makes full use of the actual value of the feedback state variables. At the same time, the second-order Euler discrete method is used to further improve the model progress. Simulation and experimental results show that the model predictive control strategy with error feedback can effectively improve the steady-state speed control performance of the system while maintaining the dynamic performance of the original system and the decoupling control effect of the two motors.
New generation single-phase charge-control intelligent electric energy meter based on remote interaction
Authors: Bao Jin , Ji Feng , Li Jun , Lu Shufeng
Published: October 2020

The single-phase charge-control smart energy meter adopts the most advanced energy meter ASIC, microprocessor materials, non-volatile memory, permanently stored information, wide-screen LCD and other advanced technologies. A set of high-accuracy, wide-load, high-sensitivity, low-power-consumption, which is used for measuring the rated frequency of single-phase power grid 50 / 60Hz, in AC active energy meters. This single-phase electricity meter integrates multiple functions in one to realize active and active measures for energy to achieve remote real-time voltage, current, neutral current, power, power factor, and the use of remote systems to achieve sales of electricity users Pre-emptive prepayment. It can flexibly set various functions: free electricity consumption, fault alarm, automatic power off, record opening, automatic meter reading.
Research and Design of an Intelligent Charging and Self-checking Car Charging Pile
Authors: Ji Feng , Bao Jin , Li Jun , Lu Shufeng
Published: October 2020

This paper develops an intelligent, efficient, stable and reliable AC charging pile system. In order to achieve the goal of stability and reliability, the power supply uses a high-frequency switching power supply. The topology design must be reasonable. The power components selected can meet the working needs of the high-frequency switching power supply. In order to realize the automatic control function of the charging pile system and achieve the requirements of intelligence, the S3C44BOX embedded microprocessor is designed as the main controller of the charging pile system to realize various functions such as charging control and communication.
Design of lossless snubber circuit for phase-shifted full-bridge converter
Authors: Ji Shengxian , Jie Guisheng , Gao Shan , Wang Hengli , Wang Ruitian , Liu Xiaohu
Published: October 2020

In the phase-shifted full-bridge circuit, the voltage spike caused by the hard turn-off of the switch tube increases the voltage stress of the switching device. Due to the existence of energy-consuming components such as resistance in the traditional absorption circuit, the efficiency is not always high. Based on the RCD snubber circuit, a low-loss absorption circuit is designed in this paper. This circuit absorbs voltage spikes through an absorption capacitor, and then slowly releases energy through an oscillating circuit consisting of current-limiting inductance, stray inductance, and absorption capacitance. The current-limiting inductance reduces the current stress of the blocking diode effectively, which can be achieved with the absorption not being affected and the power loss being reduced. Finally, the absorption effect and energy loss of the new low-loss absorption circuit and the commonly used RCD circuit were simulated and compared in PSpice software, and verified its feasibility.
Research on MPPT technology based on three-stage variable step size disturbance observation method
Authors: Hai Tao , Chen Yongjian , Shi Yu , Li Junjie , Liu Zhenyu
Published: October 2020

For the traditional disturbance observation method, it is impossible to take into account both tracking speed and steady-state accuracy with a fixed step size, so we change the step size and propose disturbance observation method based on three-stage variable step size. The specific method is to set the basic step size and the slope threshold of the P-V curve, and then scale factors according to the interval segment of the slope value of the working point, so as to realize the dynamic adjustment of the step size. Simulation experiments show that after the algorithm is improved, the tracking speed is faster when the environment changes suddenly; when the environment is stable, the power oscillation is reduced. The above has certain positive significance for improving efficiency of the photovoltaic system.
Research on Adaptive Waveform Optimization Design of Anti-jamming Radar
Authors: Zhao Zhixiang , Yuan Jiali , Li Minxing
Published: October 2020

With the rapid development of science and technology, the development of radar in China has entered a new stage, but the signal interference problem is still a bottleneck restricting the accuracy of radar detection. Based on this, this paper conducts waveform optimization design research on radar anti-interference and improved detection accuracy. Firstly, the radar is outlined, then six commonly used radar anti-jamming technologies are introduced. Then the characteristics of modern radar anti-jamming technology are analyzed. Finally, the radar waveform is optimized. Through the waveform design adaptive mechanism and simulation, we find that as the number of adaptive iterations increases, the detection probability of interest targets is increasing.
Research on Superconducting Qubit Manipulation Based on Arbitrary Waveform Generator
Authors: Wu Hengkui , Zhu Weiguo , Pang Jinhao , Cheng Zhen
Published: October 2020

Quantum computing is an emerging technology which will influence the future. Quantum computing is currently limited by the scalability of qubits, especially the qubits manipulation of superconducting computing. In this paper, a superconducting qubits manipulation method based on AWG (Arbitrary Waveform Generator) is proposed. Based on the superconducting quantum computing system, the overall scheme of qubits manipulation is presented, including overall framework, multichannel coherent arbitrary waveform generation design, quantum state reading and acquisition design, multichannel synchronization design and quick feedback transceiver design. The simulation and experiment results show that the proposed method has good scalability, high synchronization index and good signal quality, which can meet the requirements of superconducting quantum computing for qubits manipulation.
An Efficient Method for Prediction of the Flow-induced Vehicle Interior Noise
Authors: Liu Yingjie , Lu Wenbo , Zhang Qi , Wang Xing , Yin Xiang , Hou Hangsheng
Published: October 2020

Wind noise is an important attribute for vehicle interior quietness. To improve the efficiency of wind noise simulation, a method of Stochastic Noise Generation and Radiation (SNGR) is used to rebuild the flow field based on steady simulation result. For wind noise simulation, the flow field result of transient simulation is only applied to low frequency, and the result of the SNGR method is applied to middle and high frequency. Finally, correcting the SNGR result by correction coefficient and combining the two results. The experiment and simulation results have good agreement. The results shows that the hybrid method for predicting the wind noise in vehicle can not only obtain good results, but also improve computational efficiency.
Research on Solve of Heat Transfer Coefficients and Experimental of the Heavy Plate in laminar cooling process
Authors: Wang Junlin , Xie Zhi , Liu Wenhong
Published: October 2020

Heat transfer model is the premise of adjusting cooling control strategy in laminar cooling process. The accuracy of heat transfer coefficient directly affects the accuracy of the temperature model. However the accuracy of heat transfer coefficient is difficult to determine. In this paper, the model of heat transfer coefficient is solved by using chaos particle swarm optimization algorithm. The experimental system was designed and the temperature drop of the points in the plate was measured in laminar cooling process. Compared with the experimental results, the average error of the measurement points is 5.2°C, and the standard uncertainty is 1.4°C. It is proved that the calculation method of heat transfer coefficient is better than empirical formula at the same cooling condition.
Study on the Design of Passive Containment Heat Removal System
Authors: Song Jie , Liu Le , Gong Daxin , Wang Jue , Wang Xiaoxiao
Published: October 2020

The containment is the last barrier to prevent the release of radioactive material into the environment after an accident. If the pressure of the containment vessel exceeds the ultimate carrying capacity of the containment, a large amount of radioactive material leaks into the external environment after the accident. The author designs a set of passive containment cooling system based on sea shipping space constraints. The head period of cold leg double side shear fracture accident of long-term containment thermal response is analyzed in detail. The analysis results show that the loss of coolant accident occurs within 72h, the passive containment cooling system can ensure the safety of pressure, which meets the design requirements.
Research on Application of Mathematical Model in Cost Fuzzy Control
Authors: Liu Shuju
Published: October 2020

The main goal of mathematical modeling is to deal with the problems of economic and ecological environment, daily life, etc., and to extract real problems and abstract them into mathematical models, and then to obtain the solution of the model, verify the scientificity of the model, and use the answers obtained by this model. Explain real problems. Through a series of related studies, this article guides the internal work of many real-world organizations, such as saving costs, reducing wood, and improving economic efficiency.
RETRACTED: Research and Implementation of The Fault Information System FOR Relay Protection Based on Cloud Computing Technology
Authors: Wang Junlong , Wang Lei , Dong Guowei , Yuan Zehong , Zhang Jinsong , Wu Xiaojie
Published: October 2020

With the continuous development of smart grid technology, it is of great engineering application value and urgent practical demand to collect and manage more intelligently the operation and fault information of relay protection in 110kV and below substation. With the introduction of “cloud computing” technology, a cloud platform of fault information with good expansibility, high stability, loose coupling, strong reusability and convenient maintenance could be built up, which is the core of the system construction. In order to make full use of the existing data network channels and network resources in 110kV substation, a fault information system of relay protection, with its sub-station modeling and communication management, is presented based on “cloud computing” technology to realize a more efficient and convenient relay protection exchange between 110kV substation and the dispatching control center.
Application of Ant Colony Algorithm to Air Route Planning in Helicopter Submarine Searching
Authors: Li Lin , Zhou Zhiying , Han Qiang , Yu Jie , Lv Xinyi , Bi Simin
Published: October 2020

Air route planning system is the core of antisubmarine call-search mission which is carried out by an ASW helicopter, and the efficiency of mission completion is decided by the algorithm adopted. Considering actual army training and combat, this paper analyses the basic elements of responding-antisubmarine air route planning system systematically, constitutes assessment index of air route planning system, presents the constraint conditions which should be considered by the system and carries out simulation calculation by ant colony algorithm. Finally, this paper summarizes the applicable circumstances of responding-antisubmarine air route planning methods based on ant colony algorithm, which will be of great value to improve army combat and training efficiency.
A Modified RR-ALOHA Protocol for Safety Message Broadcast in VANETs
Authors: Huang Zhong , Xu Rui , Chu Chu , Wen Guangjun
Published: October 2020

MAC protocol design of VANETs is a real challenging task due to the high mobility and mobile hidden terminals (MHTs) issues. Slotted ALOHA based MAC protocols is regarded as one of the most promising solution in which hidden terminals issues are solved by broadcasting frame information (FI). However, when network topology changes rapidly, the vehicles using the same slot comes close to each other, merging collisions take place and a new round of slot reservation is required. This paper proposes a modified Reliable Reserved ALOHA (RR-ALOHA) protocol in which merging collisions are detected and an election process is employed to reduce collisions directly after one merging collision. Simulation results show that our proposal achieves better packet delivery ratio than RR-ALOHA in most scenarios.
Control strategy of doubly-fed induction wind turbine
Authors: Yao Zenghui
Published: October 2020

Based on the principles of DFIG, this paper establishes a DFIG model in a synchronously rotating dq coordinate system. For the grid-side control system, the vector control technology facing the grid voltage is used to realize the decoupling of DFIG active power and reactive power. The methods of feedforward compensation and PI control are used to control the rotor side of the DFIG. When the voltage drops above the low voltage ride-through operating standard curve, DFIG should not leave the grid. When the grid voltage drops below 0.9 times the standard unit value, DFIG should also provide reactive power to the grid to support the grid voltage. Since the reactive power that can be provided by the stator side is much greater than the reactive power on the rotor side, when the grid voltage drop is small, the stator side first provides reactive power to the grid. When the grid voltage drops more, the stator side and the rotor side share power to the grid to provide reactive power. Finally, using MATLAB/Simulink software to simulate DFIG, verify the effectiveness of the control strategy proposed in this paper, and lay a foundation for fault characteristic analysis.
Application of Extreme Value of Nonlinear Regression Function Based on RSI Expert System
Authors: Zhang Shaohe , Liu Hui , Xiao Zongna , Wang Pin
Published: October 2020

This paper defines the waveform function and its corresponding concepts and axioms. The extreme value of stock price function is obtained from 24 known regression functions by using the method of seeking the extreme value, which is proven by the Shanghai stock index rising by 458.43%, 487.83% and 133.30% respectively in three different periods. This paper optimizes the expert RSI trading system with the method of mathematical extreme value, and writes the source code of the optimization formula, which provides a graphical and intuitive tool for investors. The average annual return, average winning rate and average net interest rate of waveform increasing function samples are 67.52%, 96.88% and 84.40%, respectively. The average annual return, average winning rate and average net interest rate of waveform decreasing function samples are 22.27%, 83.33% and 26.03%, respectively.
The Application of Lagrange Relaxation on Taxi Dispatchments During Evening Rush Hours
Authors: Qu Huijie , Zhao Zhi
Published: October 2020

The city transportation status is directly related to the taxi supply arrangements during evening rush hours. The operation times, operation nature, operation requirements, vehicle resource types and quantities will have big influence on taxi drivers’ dispatchments, it is comparatively difficult to dispatch reasonably. This paper uses Lagrange Relaxation to solve the problem of taxi supply and demand during evening rush hours. NP-Hardness is the difficult point of dispatchments, thus Lagrange method is used to result an optimal solution on taxi dispatchments within reasonable calculating time, while the bottom limits of the approximate optimal solution and the approximate solution are resulted as well. This method can effectively solve the problem of the balance of taxi supply and demand during evening rush hours. Based on this, the dual problem is solved by using incremental subgradient method, while an improved strategy is proposed to rise the convergence rate.
Comprehensive Evaluation and its Application in Mathematical Modeling
Authors: Duan Luling , Ling Zhonghua
Published: October 2020

This paper first introduces the comprehensive evaluation and its purpose, five elements of comprehensive evaluation, and gives the establishment methods of the comprehensive evaluation model, including linear weighting method, nonlinear weighting method and approximate ideal point method. Secondly, the general steps of comprehensive evaluation are summarized, and the treatment methods of evaluation indexes are given: using minimizing – maximizing, centering – maximizing and interval - maximizing to achieve the consistency of index types; using vector normalization, extreme difference transformation, standard sample transformation and linear proportional transformation to standardize index types; using expert consultation and relative comparison to determine the weight of index. Finally, a comprehensive evaluation model of aircraft type is established.
Study on the application of elementary number theory in conflict algorithm
Authors: Zhao Zhi , Huang Jinde
Published: October 2020

Analyze the time complexity of the algorithm, for multiple threads to execute multiple transactions at the same time, and map the result of the remainder of the prime number to the hash address. After calculation, the formula is a convergent array. The larger the value of x, the smaller the calculated value, indicating that the algorithm can complete the task in a certain limited time. Applying the probability of random prime numbers to the design of conflict management algorithms can avoid endless waiting for each other between transactions, and also avoid the waste of computing resources caused by cancelling earlier transactions. Compared with the radical algorithm of direct termination, this algorithm gives the transaction a certain waiting and retry time, avoids the long execution of the long transaction, and guarantees the commit time of the transaction.
The Propositions and Proofs in Algebra System
Authors: Chen Shiqing
Published: October 2020

In the study, it was proved that the algebra system

(
a
+
b
p
,
⊕
,
⊙
)

=

{
a
+
b

2

|
a
,
b
∈
Z
}

is a Ring of integers and not a domain, and when

2

is extended to the prime number, the conclusion is correct. When a and b are Rational number and Real number, it proves that Algebra System

(
a
+
b
p
,
⊕
,
⊙
)

=

{
a
+
b

2

|
a
,
b
∈
Z
}

is a domain and extends

2

to

5

until p is the prime number. The conclusion is correct. Finally, the judgment method of Subdomains is used to prove that when a and b are plural, I = {a + bi|a, b ∈ Q}is a domain.
Application of Multiple Regression in Mathematical Model of Air Quality Calibration
Authors: Que Xiaohua , Li Hong
Published: October 2020

Based on the existing self-built point data, state-controlled point data and wind speed, pressure, precipitation, temperature, humidity and other data, a multivariate regression mathematical model is established in this paper to optimize the self-built point data. The model is optimized via data to find out the factors that have great influence on the data of self-built points and get more accurate regression equation model. After verification, it can be seen that the calibration degree of the model to the self-built point data is high.
Vehicle Path Tracking Maneuver Based on Model Predictive Control Theory
Authors: Xu Qijiang , Wang Jian , Zhao Wenzheng , Ding Jinchuan , Liu Xinjie
Published: October 2020

Vehicle path tracking problem has been a hot research topic in the field of automotive safety. Therefore, combined with a 3-DOF vehicle model is established. The basic idea behind the work was to identify the optimal steering angle input during a vehicle travels along a prescribed path. Based on Model Predictive Control (MPC), the steering angle input was determined as the control variable, tracking the desired path was determined as control object. By using the Model Predictive Control, the optimal control problem was converted into a secondary plan problem which was then solved by the active set method. The results show that the minimum error of lateral position for the generated path-tracking trajectory can be good indicators of successful solving of the path-tracking problem in vehicle handling inverse dynamics for MPC. The study can help drivers identify safe lane-keeping trajectories and area easily as well as evaluating performance of emergency collision-avoidance for a vehicle.