bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on a Design Algorithm of Dynamic Spectrum Access Criterion
Authors: Teng Xiaoyun , Xie Jun , Dai Xuefeng 
Published: October 2020

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.