bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of A Free Floating Ultrasonic Inner Spherical Detector for Pressure Pipeline
Authors: Du Xingji , Fang Xin , Tian Wei , Tang Ping , Miao Cunjian 
Published: June 2021

Abstract
Ultrasonic inspection of the corrosion and scaling in industrial pressure pipelines is necessary due to the adverse effects of defects on medium flow and heat transfer. In this paper, a free floating ultrasonic inner spherical detector has been designed to detect and locate defects in pipelines. The flange mechanical structure of ultrasonic inner detection intelligent ball meets the internal space requirements and external environmental requirements. They are connected of two parts flange type. A complete set of spherical shell structure design covering the functions of sealing and external pressure resistance is proposed and completed. One part is the inner sphere, and the other is the outer shell. Pipeline experiments show that the spherical detector can reach the exit smoothly through curved pipes, inclined pipes and vertical pipes without jamming and stable motion attitude, collects all kinds of information along the way, determines the existence of defects and achieves accurate positioning.
Application and research of patent evasion design in automatic connection device
Authors: Zhen-guo Li , Gong-chang Ren , Yue-xin Yang , Le Wang 
Published: June 2021

Abstract
The patent evasion design may reduce the value of the original patent. In order to avoid this possibility, it is necessary to analyze the development status of the patented technology while conducting the patent evasion design. Combining value analysis with patent evasion methods, a patent evasion design method based on value analysis is proposed. Firstly search related patents by identifying multi-level keywords to obtain the target patent database; then predict and analyze the maturity of the database patents to determine the core patent group; the structure/function model of the core patent is established and its value analysis is analyzed to find the low-value components as the target technology of the circumvention design; next, the contradictory points of the target patent are found through the TRIZ theoretical tool to perform the evasion design, and the new scheme is obtained and the infringement judgment is made. Finally, the method was verified by an automatic connecting device, and the result showed that the improved automatic connecting device has the advantages of simple structure and convenient operation.
Quadrotor Flight Control Based on Improved Active Disturbance Rejection Control Technology
Authors: Xiyang Wang , Mingqiu Li , Yang Yang , Hongtao Duan 
Published: June 2021

Abstract
This paper proposes a four-rotor attitude control method based on improved active disturbance rejection control. Based on the analysis of the active disturbance rejection controller from the deviation theory, it is found that the extended state observer has problems such as high steady-state error and difficulty in parameter selection. Then, an improved extended state observer was designed structurally, its stability was proved and the error was compared with the traditional extended observer, and the improved auto-disturbance rejection control was applied to the attitude control of the quad-rotor UAV. Finally, the simulation verification of the controller is carried out from various aspects of attitude tracking, height-fixing experiment, external force interference test and wind interference test, and compared with traditional ADRC, the comparison results show that its performance is better than traditional ADRC.
Research on the Design of Brake Auxiliary Device Based on the Improvement of Riding Safety
Authors: Zeng Xi , E Zheheng 
Published: June 2021

Abstract
Purpose: In order to improve the safety of the braking action of cyclists during the riding process, to meet the diversified riding needs of cyclists, and to take care of special riding groups to achieve the purpose of improving user experience. Method: Use ergonomics to guide the design of bicycle brake assist device, analyze from the perspective of ergonomics the elements and methods for achieving safe operation during bicycle braking, and complete the design of the brake assist device based on this analysis. Conclusion: It provides a new type of braking mode, reduces the difficulty of braking, improves the riding safety and comfort, and makes the product have important application value and better base on the market.
Research on feasibility verification method of pipe bending angle correction
Authors: Guo W S , Guo R , Sun H H , Wang W , Yang X 
Published: June 2021

Abstract
Certain types of rocket engine pipes can only be cut perpendicular to the axis when cutting margins. In order to verify whether the pipeline can achieve the cutting margin perpendicular to the axis by correcting the bend angle, and finally perform accurate assembly, a verification method based on SolidWorks to simulate the pipe shaping process is proposed. First, the pipe model was reconstructed by using the measurement data. Second, the lengths of the pipe segments, the angles between the line segments and the angles between adjacent surfaces were extracted. Third, the simplified pipe model and interface model were established and assembled in SolidWorks. Finally, the angle constraints of the adjacent surfaces were added, and the angle constraints of the line segments were released. According to the assembly results, the feasibility of solving the problem through shape correction was analysed. Experiments show that this method can effectively verify the feasibility of the shape of the elbow, and also provide the shape of the pipe after the correction and the angle of each elbow.
Hand Gesture Controlled Nursing Bed Using FMCW Radar
Authors: Du Fuchuan , Zhao Yue , Wang Haili , Cao Qixin 
Published: June 2021

Abstract
The nursing bed has become an important tool for medical and elder care, as a well-designed bed can prevent users from bedsores. To improve the user convenience, a user-friendly human-computer interface is also necessary. In this paper, we design a new nursing bed containing a FMCW millimeter wave radar for gesture recognition. A control system can help user frictionless back-up, integral turning over and leg raising when lying in the bed. Besides, we adopt the convolutional recurrent neural network for recognition of 6 gestures. Experiments with the nursing bed show that the control success rate of the bed reaches 93.75% and the response time achieves 1.03 s.
Research on the scheme of radio cooperative spectrum sensing for offshore ships based on trust degree in Ad Hoc network mode
Authors: Zhang Jiaming , Zhang Baihai , Chai Senchun , Cui Lingguo , Yao Fenxi 
Published: June 2021

Abstract
Radio communication is an important part of maritime communication. As the number of ships in the offshore area continues to increase, spectrum resources appear to be particularly tight. In this work, a trust-based cooperative spectrum sensing scheme in Ad Hoc network is proposed to improve the accuracy and reliability of maritime radio communications. This scheme first divides the ship nodes into different subnets according to the Ad Hoc network protocol. And after the malicious ship nodes are selected based on actual conditions, a trust-based collaborative spectrum sensing fusion method will be given, that is, a smaller trust weight is given to malicious nodes, the method will be more trustworthy to receive the spectrum occupancy information provided by ship nodes with a higher degree of trust. Simulations have been performed to illustrate the high detection probability of the proposed spectrum sensing scheme. Therefore, it is feasible and beneficial to apply the proposed spectrum sensing scheme to improve the trustworthiness of maritime radio communication.
A SlW-CPW-fed high-gain antipodal Vivaldi antenna with elliptical dielectric lens
Authors: Zhen Fajian , Li Xingguang 
Published: June 2021

Abstract
This paper proposes a Ka-band high-gain antipodal Vivaldi antenna. The antenna is designed by SIW-CPW power feed. Both ends of the radiating arm are loaded with elliptical patches, claw-shaped slots and rectangular corrugations are loaded on the patch, and elliptical lens are loaded on the front end of the radiating arm, and four rows of metal strips are loaded on the lens. The proposed antenna has overcome the shortcomings of the traditional Vivaldi antenna’s high feed loss, and better improve the antenna gain. The Ka-band antenna shows excellent radiation performance, with a peak gain of up to 12.1dBi.
Research on obstacle avoidance method of robot manipulator based on binocular vision
Authors: Zhang Xiaoyang , Guo Xiaoming , Sun Zhenyu 
Published: June 2021

Abstract
Aiming at static obstacles in indoor environment, the six-axis robot manipulator can avoid obstacles successfully through binocular stereo vision system. According to the principle of camera imaging, the camera calibration is completed by using the camera calibration toolbox of MATLAB, and then the three-dimensional coordinates of the feature points of obstacles are obtained by using the Structure from Motion (SFM) algorithm, so as to determine the location of obstacles. In the aspect of path planning, combining the characteristics of binocular visual obstacle recognition, the artificial potential field (APF) method is used to realize the obstacle avoidance. Finally, the simulation and data analysis under the Matlab development environment verify the feasibility of the algorithm in the binocular vision obstacle avoidance system.
Research and application of TRIZ theory in the field of service robots
Authors: Jiahao Feng , Gongchang Ren , Yuexin Yang , Yadong Shang 
Published: June 2021

Abstract
Service robots in China are in the rapid development, with an increasing proportion in the field of robotics, but there is still a big gap with other developed countries in the core technology, systematic innovative design theory guidance is particularly important. Therefore, FEPAM model (function-effect-process-action-mechanism model) and TRIZ (Teoriya Resheniya Izobreatatelskikh Zadatch) were integrated. First of all, through the analysis of the market demand and existing products, the working mechanism is decided. According to the mechanism, the process action process is conceived. Finally, the executive mechanism that needs to be improved is determined. By establishing the Su-field type and adopting the corresponding standard solution, the product function innovation is realized. The proposed method is applied to a delivery robot, and the problem of inconvenient man-machine operation is solved quickly. The results show that the proposed model can improve the solving speed of the Su-field model, enrich the standard solution model, and provide a new idea for the future development of Su-field model.
Water Leakage Detection Based on Variation Bayesian Neural Network Autoencoder
Authors: Feng Pengyu , Shen Yixuan , Liu Weiming 
Published: June 2021

Abstract
Water pipe leakage detection is of great significance to the protection of water resources in our country. However, the detection accuracy of water pipe vibration signals is easily affected by external noise. Existing detection technologies are difficult to reduce the influence of noise signals, and some machine learning based outlier detection models are not very robust. Variation Bayesian neural network Autoencoder (VBAE) replaces the fully connected layer network in encoder and decoder with Bayesian neural network (BNN) on the basis of Variation Autoencoder (VAE). VAE has a strong generalization ability, while BNN has an uncertainty quantification ability. VBAE combines the advantages of the two models and is very robust. Experiments have proved that, compared with other models, VBAE for water leakage detection can greatly reduce the influence of noise on the output of the model, and has a better detection effect.
Lightweight robust optimization design of mechanical claws of intelligent sanitation vehicle
Authors: Li Ran , Xu Xiang , Chen Jiawei , Chen Xinbo 
Published: June 2021

Abstract
As the dustbin grabbing device of the intelligent sanitation vehicle, the dimension errors caused by the manufacturing process should be considered in the lightweight design process of the mechanical claws. In this study, we used the mechanical claws as the carrier. The maximum deformation and the maximum equivalent stress of them were taken as the design responses and the plate thicknesses of different parts were taken as the design variables. A light-weight robust optimization design method for the mechanical claws was proposed by combining the optimal latin hypercube experimental design with high-precision Kriging approximate model and using Particle Swarm optimization (PSO) as the optimization solver. The optimization results show that this method has higher robustness than traditional deterministic methods although it has lower lightweight requirements. The final structural design of this study has higher advantages in preventing the fluctuation of uncertain parameters.
Rolling Element Bearing Fault Diagnosis for Complex Equipment based on MFMD and BP Neural Network
Authors: Liu Junfeng , Yu Xiang 
Published: June 2021

Abstract
A new fault feature extraction method for rolling element bearing is put forward in this paper based on modified Fourier mode decomposition (MFMD) and multi-scale permutation entropy, and the fault pattern recognition is studied by combining BP neural network. First, introduce frequency band entropy (FBE) to optimize the boundary frequency search and effective modal component selection of Fourier decomposition. Then, use MFMD to adaptively decompose the original vibration signal to several Fourier intrinsic mode functions (FIMFs) and select effective FIMFs. Next, use multi-scale permutation entropy to quantify the fault features. Finally, input the fault feature vector into the BP neural network for fault diagnosis model training and testing. The method proposed in this paper is applied to the rolling element bearing simulation data and the public bearing fault test data set of Case Western Reserve University to verify the feasibility of the method. The results show that the method proposed in this paper has a high identification accuracy for different types of faults, reaching over 98%. The feasibility and superiority of the rolling element bearing fault diagnosis method based on MFMD and BP neural network are verified, and technical support is provided for the health state assessment of rolling element bearings.
Automatic detection of COVID-19 chest X-ray based on Convolution Neural Network
Authors: Ye Qing , Tan ZeXian 
Published: June 2021

Abstract
Currently, chest X-rays, as one of the auxiliary diagnostic methods for COVID-19, play an important role in the detection of COVID-19. In this paper, we propose an automatic detection method of COVID-19 chest X-ray based on Convolution Neural Network. In this method, we first get an image of the chest by X-ray, and then we preprocess the chest X-rays, and then send the preprocessed X-ray images to the convolutional neural network for feature extraction and classification, and finally we were able to diagnose whether COVID-19 or not. We test the three types of models (Inception V3, ResNet and DenseNet) under different layers, and finally propose the automatic detection method of COVID-19 chest X-ray. After a large number of experiments, the highest accuracy rate of COVID-19 detection is 98.059%. Compared with other studies in the same period, our accuracy rate is higher, and it is very fast. This indicates that our proposed method can be used as an auxiliary detection for COVID-19.
Analysis of Contact force optimization for a hybrid manipulator
Authors: Canguo Zhang , Shaolei Wang , Yi Lu , Xiaoyu Ni , Chunhua Zhu 
Published: June 2021

Abstract
A novel hybrid manipulator is designed. Based on the fact that the sum of the external force vector for the object is zero, the criterion of the stability of the object is derived. The formula for calculating contact force of fingers was deduced by matrix theory. The maximum frictional force was taken as boundary condition, then the contact force of fingers was optimized. The advanced CAD software was used to simulate the process of grasping the object. The stability of the object at a certain time was verified. Finally, the contact force between fingers and objects was optimized. It provides a theoretical basis for the application of the hybrid manipulator.
A study on the wear allowance of a railway vehicle hydraulic damper
Authors: Wang Wenlin , Huang Bao , Zhou Zirong , Du Jianming 
Published: June 2021

Abstract
Railway vehicle hydraulic dampers are usually subject to wear-induced premature failures, so it is meaningful to evaluate the wear allowance of the hydraulic damper. Mathematical modelling of damping characteristics of a railway vehicle hydraulic damper under wear conditions is carried out, the model describes the functions of main damping characteristics indices vs. inner tube wear M1
and rod wear M2
. Simulation is then performed using the model, and indicates that increase of M1
would lead to significant drop of the maximum extension damping force, fading of the damping coefficient and significant rising of the damping force asymmetry rate, but the maximum compression damping force keeps to be constant, while increase of M2 would lead to significant drop of almost all of the indices except for the asymmetry rate. A wear allowance line for the damper is finally obtained when both of M1 and M2 work in real situations, the area enclosed by the wear allowance line and two axles is a safe area, any dot with a combination of M1 and M2 outside the safe area means the damper has exceeded its wear allowance and should be maintained or replaced. The mathematical model and the wear allowance line obtained in this work can be used for health status evaluation and design optimization of railway hydraulic dampers.
DEKA VII Multipoint Fuel Injector Characteristics Study
Authors: Li Fu , Weidong Xiang 
Published: June 2021

Abstract
A saturated injector driver is a power transistor driver circuit that turns fully on, and electrically saturates for the entire duration of the injector pulse width. This type of driver is better used with injectors having high resistance coils (12~16 Ohm). The advantage of this type of injector driver is that electrically generated heat is dissipated through the injector and not through the power transistor of the driver circuit. The circuitry is simplified compared to a peakand-hold type driver (which requires heat sinks to dissipate the electrical load).
Research on double tower dryer based on air brake system of rail vehicle
Authors: Xu BuDu , Zhang Xuan , Zhang ShiXi , Li QingXuan , Zhu XiaoYu 
Published: June 2021

Abstract
as we all know, in the air brake system of rail vehicles, the air usually contains moisture. In order to solve this problem, the common air dryer can effectively dry the compressed air and thoroughly remove the moisture of the braking system. At present, the dryer used in vehicles has many disadvantages in logic control. The efficiency, service life and air resistance of the dryer do not meet the goal of smaller volume and higher parameter index, so a more excellent dryer is urgently needed.
A new path of energy saving and emission reduction based on the choice of matching engine oil for tor traditional energy vehicles
Authors: Changming Xia , Leping Bu , Qi Zhou , Shengliang Wang , Yanhong Guo 
Published: June 2021

Abstract
Comparative test research for the same and different models with matching type oil has been carried outunder same and different conditions. The results show that the parameters such as idle speed, load calculation value, absolute position of throttle, injection pulse width and fuel repair value of all the tested engines are reduced to different degrees by using the matching type oil. Energy consumption, emissions and other indicators of vehicles with matching type of oil have been improved after long-term tracking, especially large diesel vehicles.
Reliability analysis of the optimized carrying door frame based on six-sigma
Authors: Chen Di , Wang Yunxia , Liu Ruilong , Zhang Jun , Qiu Longjing 
Published: June 2021

Abstract
The door frame is a key component of the track door system. This paper uses the Six-sigma Analysis module in the finite element software ANSYS Workbench to analyze the reliability of the door frame, and regards its geometric dimensions and materials as random variables. Test design, Latin hypercube sampling, and Monte Carlo simulation calculations respectively obtained the reliability values of static strength and static stiffness of the door frame. The reliability values were analyzed to verify the rationality of the design.
Research on Integrated Pneumatic Control Valve Based on Frame Control Brake System of Rail Vehicle
Authors: Xu BuDu , Zhang Xuan , Zhang ShiXi , Li QingXuan , Zhu XiaoYu 
Published: June 2021

Abstract
This product is used in the frame control system of railway vehicles. It integrates remote function, anti-skid function and communication function, and highly modularizes the common braking, emergency braking and anti-skid protection functions of railway vehicles.
Effect of cooling methods on mechanical and corrosion properties of Inconel 625 during solution treatment
Authors: Li L , Liu X Y , Wang X , Wu M 
Published: June 2021

Abstract
Inconel 625 alloy is a nickel-based deformation superalloy which is widely used in aviation, ocean engineering, chemical engineering and other important fields. In recent years, with the continuous expansion in application field of Inconel 625 alloy, the requirements of mechanical properties, corrosion resistance and other comprehensive properties of the alloy are constantly improved. In this paper, hardness tester, tensile machine, electrochemical workstation, optical microscope, scanning electron microscope and other equipment are used to study Inconel 625 alloy, and the microstructure evolution law and mechanical properties and corrosion properties of the alloy under different heat treatment conditions are studied. The experimental results show that the as-cast Inconel 625 alloy is mainly composed of austenite which is displayed high hardness and poor corrosion resistance. Heat treatment is a common way for tunning the comprehensive properties of Inconel 625 alloy. After 1090°C heat treatment, different cooling method were used to tune the corrosion resistance of Inconel 625 alloy. The cooling rate has a great influence on the microstructure and properties of the alloy. After water cooling, the precipitation of Nb carbide at the grain boundary is retained, which improves the corrosion performance of the alloy. After air cooling or furnace cooling, chromium carbide precipitates in the alloy again, which leads to the decrease of corrosion properties of the alloy. The special treatment can effectively improve the corrosion resistance of the alloy, and improve the plasticity of the material without reducing the strength. This paper provides an effective basis for optimizing the heat treatment process of Inconel 625 alloy in production to improve the comprehensive properties of the material.
Optimal Design of Lifting Mechanism of Linkage Hydraulic Lifting Dam Based on MATLAB
Authors: Chen Yuanlong , Cheng Zhuangzhuang , Huang Zhendong 
Published: June 2021

Abstract
The muti-link lifting mechanism in hydraulic dam was briefly introduced. The optimization model of the lifting mechanism is established, and the stroke of the hydraulic cylinder is taken as the optimization objective. The genetic algorithm and fmincon function in MATLAB are used to optimize the connecting rod parameters. The results show that the genetic algorithm can obtain the optimal value in a small number of iterations, but it takes a long time; while the fmincon function can obtain the optimal value in a short time under suitable initial value conditions, but the number of iterations is more. It provides a basis for further research on the multi-link lifting mechanism.