bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on dynamic current sharing method of parallel connected IGBT modules for NPC three level converters
Authors: Peng Xi , Yin Sheng , Zou Yingqin 
Published: December 2021

Abstract
The parallel connection of IGBTs has been being applied in high power neutral point clamped (NPC) three level converters. This paper investigates the impact of gate parameters (gate resistor and capacitance) on dynamic current imbalance of parallel connected IGBT for NPC three level converter. A gate parameters calculation method is proposed in the paper, and the delay time and collector current difference can be analysed quantitatively. Experimental results have shown the effectiveness of the method.
Design of Smoke Alarm Disperser Based on Single-chip Microcomputer
Authors: Wang Yang , Han Lichun , Zhao Yonghui , Xue Yuquan , Wang Liming 
Published: December 2021

Abstract
With the rapid development of society and economy, various laboratories have become more complete in number and equipment, but subsequent laboratory accidents frequently occur. Therefore, it is imperative to construct a laboratory safety management system to ensure the safety of laboratory personnel and complete equipment. This article intends to design a smoke alarm, which mainly includes measuring the sensitivity of the smoke sensor to the concentration of smoke in the air, and the linear change of the sensor converting the corresponding analog signal into a digital signal. By designing the fan speed to be controlled by the change of smoke density, the speed of the motor is adjusted. And the alarm module can sound an alarm when the smoke concentration is certain, and at the same time, it can automatically cancel the alarm when the smoke concentration decreases. Finally, a simulation experiment is designed to simulate the effect of the sound alarm of the smoke alarm disperser on the dispersal of smoke under different working environments.
A design of laser array harp based on multi-dimensional wavelet transform and audio signal reconstruction
Authors: Liu Bin , Ren Yan 
Published: December 2021

Abstract
This paper introduces a design scheme of laser array harp based on multi-dimensional wavelet transform and audio signal reconstruction. The green light beams from multiple high-power lasers simulate harp strings, use photoresistors as the signal receiving end, and use a signal conditioning system composed of analog circuits and LM393 comparators to collect and adjust the resistance signal of the laser sensor[1], and finally it is adjusted to a level signal that can be recognized by the CPU. After receiving the signal, the CPU core board analyzes the string signal, and sends control commands to the audio processing system through the industrial bus according to the analyzed digital signal. After receiving the control command, the audio processing system uses the audio signal reconstruction technology composed of multi-dimensional wavelet packets, deep learning and other algorithms to simulate the audio signals of various string music, so as to achieve the purposes of using the lasers as virtual strings and imitating musical instruments for musical performance.[2]
Research on 5G positioning technology for urban canyon
Authors: Xiong Xin , Liu Shumin 
Published: December 2021

Abstract
Aiming at the problem of poor positioning accuracy of GNSS for urban canyon environment, this paper proposes a TDOA/AOA combined positioning technology based on 5G.Firstly, the AOA estimation algorithm based on conventional beam forming is compared with that based on MUSIC algorithm. Then, the weighted matrix is smoothed forward and backward.Finally, according to the measurement data of AOA and TDOA, Chan and Taylor combined localization algorithm is used to obtain the estimated location of the user.
GAN Image Generation and Detection Technology Based on Fractal Dimension
Authors: Guo Yuheng 
Published: December 2021

Abstract
With the development of modern technology today, image analysis technology has become an important research direction in the computer field. Computer image processing technology is a cross and fusion involving multiple disciplines, which includes multiple research directions such as physics, chemistry, and computer science. Starting from the fractal dimension, this article studies the image generation and detection technology. The purpose of the research topic in this article is to have a deep understanding of image generation technology so as to master image processing methods proficiently. The methods used in this article include case analysis, data, comparison, and experimental methods, etc., and carry out related researches on image generation detection technology and fractal dimension. The experimental results show that the algorithm accuracy of GAN in the detection technology of computer-generated images is higher than other algorithms, and the improvement space is about 0.06.
Comparative analysis of dynamic state recognition between permutation entropy and weighted permutation entropy
Authors: Luo Wenxiang , Wan Li , Liu Hui 
Published: December 2021

Abstract
Permutation entropy (PE) and weighted permutation entropy (WPE) are indexes of the complex system. In this paper, the nonlinear sequence of two chaotic states is simulated by Logistic mapping, and the effectiveness of the PE and WPE algorithms in chaotic state recognition is compared and analyzed with different sliding step sizes. The results show that the value of WPE changes more obviously than PE in different chaotic states, and the recognition effect of WPE is better than PE in dynamic states, which can provide theoretical support for further analyzing the complexity characteristics of actual data.
Ship classification based on random forest using static information from AIS data
Authors: Wang Yitao , Yang Lei , Song Xin , Li Xuan 
Published: December 2021

Abstract
With the wide use of automatic identification system (AIS), a large amount of ship-related data has been provided for marine transportation analysis. Generally, AIS reports the type information of ships, but there are still many ships with type unknown in AIS data. It is necessary to develop algorithms which can identify ship type from AIS data. In this paper, we employ random forest to classify ships according to the static information from AIS messages. Moreover, the importance of static features is discussed, which explains the reason why some classes of ships are misclassified. The method of this paper is proved to be effective in ship classification using static information.
Research on intelligent early warning system of rail transit line trip based on pscada
Authors: Zhang Yuqing , Zhang Xiaohong 
Published: December 2021

Abstract
In this paper, an intelligent early warning scheme for rail transit line trip based on PSCADA system is proposed. The scheme takes into account the defects of low prediction accuracy and real-time prediction caused by the lack of power data in the traditional line trip prediction method. At the same time, a large number of power data generated by PSCADA system in the long-term application process are ignored in the field of rail transit[1]. Based on this situation, the prediction data set is constructed by combining the historical power data collected by PSCADA system in rail transit and the lightning weather data in traditional prediction methods. On this basis, the lightgbm machine learning intelligent algorithm is used to compare the similar support vector machine (SVM) and logistic regression algorithm to obtain a model with good prediction effect. In practical application, the real-time data set is constructed by using the real-time power data and real-time weather data collected by PSCADA system to predict, and an intelligent early warning system with the dual advantages of real-time and high accuracy is obtained.
Finger joint angle estimation based on sEMG signals by Attention-MLP
Authors: Yu Zhebin , Wang Hui , Yu Wenlong 
Published: December 2021

Abstract
sEMG(Surface electromyography) signal was widely applied in human-machine interactive field, especially in robotic arm control. In this paper, we built the Attention-MLP (Multilayer Perceptron) model to implement a type of continuous joint angle estimation method based on sEMG for six grasp movements, we tested this model on Ninapro dataset and the average Pearson correlation coefficient (CC) and the average root mean square error (RMSE) of the proposed Attention-MLP method achieved 0.812±0.02 and 10.51±1.98; the average CC and RMSE of this method are better than Sparse Pseudo-input Gaussian processes (SPGP), its average CC and RMSE are 12.14±2.30 and 0.727±0.07. Compared with the traditional method SPGP, our model performed better on continuously estimation of ten main hand joint angles under 6 grip movements.
Identifying important nodes from content-associated heterogeneous graph by LeaderRank
Authors: Dai Yulong , Shen Qiyou , Xu Xiangqian , Yang Jun 
Published: December 2021

Abstract
Most real-world systems consist of a large number of interacting entities of many types. However, most of the current researches on systems are based on the assumption that the type of node or link in the network is unique. In other words, the network is homogeneous, containing the same type of nodes and links. Based on this assumption, differential information between nodes and edges is ignored. This paper firstly introduces the research background, challenges and significance of this research. Secondly, the basic concepts of the model are introduced. Thirdly, a novel type-sensitive LeaderRank algorithm is proposed and combined with distance rule to solve the importance ranking problem of content-associated heterogeneous graph nodes. Finally, the writer influence data set is used for experimental analysis to further prove the validity of the model.
A simplified algorithm for 3D mesh model considering the influence of edge features
Authors: Lv Rumeng , Chen Xiaobing , Zhang Bingying 
Published: December 2021

Abstract
Aiming at the problem that most of the existing grid simplification algorithms for 3D models can not deal with a large number of boundary or non-popular grid models, this paper proposes a grid simplification algorithm for 3D models based on traditional algorithms. The algorithm mainly studies the geometric features of the model, considering the calculation methods and characteristics of edge shrinkage, and introduces the edge feature factors on the basis of the traditional algorithm, that is, the triangular area and side length factors of local area are introduced in the calculation of folding cost. In addition, the gaussian curvature characteristics of the 3D model are also included. Experimental results show that the proposed algorithm can keep the detail features of the mesh model well, and greatly reflect the quality and effect of mesh simplification after simplification.
Discussion on Remote Monitoring and Fault Analysis Technology of Mechanical Manufacturing Equipment
Authors: Guo Pengyu 
Published: December 2021

Abstract
Due to the interference of external factors, it is essential to adopt scientific and reasonable remote monitoring methods in mechanical manufacturing. Remote monitoring can ensure the efficiency of abnormal data acquisition, identify faults, improve equipment efficiency, save maintenance time, prolong service life, improve efficiency, and ensure the service life of machine production equipment. Therefore, it is necessary for the subordinate departments to effectively combine the actual situation and introduce some advanced technologies to effectively identify the remote controller and faults and ensure the regular and stable operation of the machine.
Rolling bearing fault diagnosis based on MEEMD sample entropy and SSA-SVM
Authors: Li Xuguang , Fu Liyou 
Published: December 2021

Abstract
The penalty parameter (c) and kernel parameter (g) contained in Support Vector Machine (SVM) cannot be adaptively selected according to actual samples, which results in low classification accuracy and slow convergence speed. A novel sparrow search algorithm was used to optimize the parameters of SVM classifier. Firstly, an improved ensemble empirical mode decomposition (MEEMD) method was used to decompose non-stationary and nonlinear vibration signals, and the eigenmode function (IMF) was obtained by removing abnormal signals from the original signals through permutation entropy, and the sample entropy was extracted. Finally, a fault diagnosis model based on SSA-SVM is constructed, and the high recognition rate and effectiveness of this method are proved by simulation and experimental data analysis.
Dual Fano Resonances Induced by Rectangle-based Plasmonic Resonator for Refractive Index Nano-sensor
Authors: Zhang Yang 
Published: December 2021

Abstract
A tunable dual Fano-like plasmonic structure consisting of metal-insulator-metal (MIM), baffle and a rectangular cavity containing two identical rectangular metal blocks is obtained. Numerical simulation results show that there are dual Fano resonances in the transmission spectrum of the structure, which can be tuned by changing the geometric parameters of the structure. In addition, due to the apparent asymmetry of the Fano resonances, the system was developed as an effective refractive index sensor (RIS) with a sensitivity of 853 nm/RIU and figure of merit (FOM) of 1631. It is considered that this structure has important application value in high integrated photonic circuit.
Research on position offset compensation of underwater manipulator
Authors: Ren Shanbin , Zhang Hui , Li Kai , Cheng Yujun , Liu Xin , Duan Derong 
Published: December 2021

Abstract
A compensation method for end position offset of underwater manipulator is presented in this paper. Firstly, the end deformation of the underwater manipulator is obtained by ANSYS analysis, and then the end position offset equation is obtained by MATLAB curve fitting. Finally, the equation is added to the kinematic model of the underwater manipulator, which improves the accuracy of the kinematic model of the underwater manipulator and lays a foundation for the accurate position control of the underwater manipulator.
Short-term wind power prediction based on hybrid variational mode decomposition and least squares support vector machine optimized by improved salp swarm algorithm model
Authors: Su Zhongde , Lu Huacai 
Published: December 2021

Abstract
To improve the accuracy of wind power prediction, a short-term wind power prediction model based on variational mode decomposition (VMD) and improved salp swarm algorithm (ISSA) optimized least squares support vector machine (LSSVM) is proposed. In the model, the variational modal decomposition is used to decompose the wind power sequence into multiple eigenmode components with limited bandwidth. The improved salp swarm algorithm is employed to tune the regularization parameter and kernel parameter in LSSVM. The proposed wind power prediction strategy using mean one-hour historical wind power data collected from a wind farm located in zhejiang, China. Compared with other prediction models illustrate the better prediction performance of VMD-ISSA-LSSVM.
Numerical research on thermal stress of steam cooler tube sheet mechanical structure
Authors: Wu Jun , Zheng Zhaoli , Li Yong , Pang Jie , Ke Zhiwu , Zhang Nan 
Published: December 2021

Abstract
Steam cooler is one of the most important mechanical equipment in thermal power generation system and nuclear power generation system. The steam cooler bears a huge temperature gradient load when the working conditions are switched. In order to analyze the thermal stress of steam cooler tube sheet with high temperature load under harsh working conditions, the thermal-structural coupling analysis model of steam cooler tube sheet is constructed with finite element method. The results show that the stress concentration exists at the position connection between heat exchanger tube and cylinder. The maximum stress is located at the outermost heat exchanger tube with the peak stress of 320MPa. The heat exchanger tube layout alone cause higher stress. This situation should be avoided in the design of heat exchanger tube sheet. Furthermore, the strength and safety of the steam cooler tube sheet are evaluated with the stress linearization method. The steam cooler tube sheet design meets the safety requirements of structural strength under high temperature load.
Experimental Research on Rubber Compatibility of Drive Train oils used in Construction Machinery
Authors: An Haizhen , Liu Min , Zhen Penghou , Chen Li 
Published: December 2021

Abstract
The compatibility of oil and rubber in the drive train system of construction machinery plays an important role in the safe and reliable operation of the system. In order to investigate the rubber compatibility of drive train system oil of construction machinery, the changes of rubber sheet volume and hardness before and after immersion of standard fluororubber (FKM2) and hydrogenated nitrile rubber (HNBR1) with 9 kinds of drive train system oil were tested. The results show that FKM2 has good rubber compatibility with drive train oil, and HNBR1 is only compatible with some drive train oil; The volume change rate and hardness change range of FKM2 are smaller than those of HNBR1.
Dynamics modelling and analysis of a large-load swinging platform
Authors: Li Meng , Han Xianguo , Geng Ruihai 
Published: December 2021

Abstract
Swing platform is widely used to simulate the motion attitude of vehicles, ships and aircraft while carrying large loads. Aiming at the excessive driving force and output power of the driving parts caused by the large load swing platform, a new swing platform which can bear the large load was established. The swing platform is equipped with four spring branch chains between the moving platform and the static platform of the 6-UPS parallel mechanism, so as to offset the gravity of the large load and the inertia force of the large load in the process of motion, and the driving force of each branch chain is reduced. In this paper, the structure of the swing platform is introduced, and the dynamics of the swing platform is modeled using the Newton-Euler dynamics equation. Finally, the driving force of each branch chain of the swing platform is obtained by simulation of the dynamics of the swing platform. The simulation results show that the swing platform with four spring branch chains can effectively reduce the driving force of each branch chain compared with the traditional 6-UPS parallel mechanism swing platform.
Inspection method of combine assembly quality based on optimized VMD
Authors: Xuan Menghui , Zhao Sixia , Liu Mengnan , Xu Liyou , Chen Xiaoliang 
Published: December 2021

Abstract
Aiming at the problems of low assembly accuracy and difficult to detect assembly quality of combine, a method of combine assembly quality detection based on sparrow search algorithm (SSA) optimized variational mode decomposition (VMD) and particle swarm optimization (PSO) optimized least squares support vector machine (LSSVM) was proposed, Firstly, the sparrow search algorithm is used to obtain the optimal VMD decomposition modal parameter K and penalty factor α, then the combined vibration signal of combine harvester is decomposed into intrinsic modal components of different center frequencies by using the best parameter combination [K, α]. Finally, the feature vector is used as the input of LSSVM classifier to classify different fault features. The analysis results show that the classification accuracy of SSA-VMD joint feature extraction method is 99.5%, which is 17.5% and 9.5% higher than ensemble empirical mode decomposition (EEMD) and fixed parameter VMD, which verifies the superiority of this method in the detection of combine assembly quality.
Characteristics Analysis of Fluid-Structure Coupling Vibration of spray bar for High gap sprayer
Authors: Xing Mingming , Jia Yanli , He Caifeng , Wang Weijia , Li Yunjie , Geng Huiwen , Cheng Rui , Gong Wendi , Liu Xin 
Published: December 2021

Abstract
With the progressive improvement of the level of mechanization of agricultural production, the high-gap rod sprayer has gradually become an important component of agricultural production equipment. The stability of spray rod has an important influence on the life and operation quality of spray rod. Therefore, considering the stability of the spray rod of high gap sprayer, a fluid-solid coupling vibration simulation model of the spray rod of high gap sprayer is established in this paper. The influence of inlet velocity, inlet pressure, fluid density and fluid viscosity on the flow rate and dynamic pressure in the pipe was analyzed by fluent. The results show that the exit velocity increases with the increase of the inlet velocity, but when the velocity reaches a certain value, backflow occurs. With the increase of inlet pressure, the dynamic pressure increases, and the local energy loss and the energy loss along the path also increase. The velocity and dynamic pressure decrease with increasing density.
Numerical Analysis of Erosion Wear of Water with Particles in Elbows
Authors: Li Chaojie , Mao Yanqin , Wang Xiaoyue , Zhan Zhixing , Cai Liang 
Published: December 2021

Abstract
In this paper, the numerical analysis of erosion wear of water with particles in elbow is carried out based on fluent. The influence of different inlet velocity and bending angle on pipeline erosion, and the distribution of pressure field and velocity field in the pipeline are studied. The main conclusions are as follows: the erosion of elbow section is more serious than that of inlet section and outlet section of pipeline. With the increase of inlet velocity, the maximum erosion rate of elbow section gradually increases, and the maximum velocity and maximum pressure inside the elbow section also increase. When other conditions are certain, different bending angles make the elbow receive different erosion effects. When the bending angle is larger, the pipeline erosion rate is relatively more uniform. Study on erosion helps to reduce the impact of fluid on the wall and improve the safety and reliability of engineering.
Rotor Position Recognition Technology of Permanent Magnet Linear Synchronous Motor Based on Sliding Mode Observer
Authors: Wang Ruihao , Pan Xiaowei , Wang Qihui , Huo Junling , Wu Hongxing 
Published: December 2021

Abstract
Position sensorless control system of permanent magnet linear synchronous motor has some advantages: simple structure, easy maintenance, high efficiency, good speed performance, etc. This paper designed a position sensorless control system of permanent magnet linear synchronous motor based on sliding mode observer, namely taking advantage of a sensorless algorithm to estimate the pole position and speed. Firstly, the principle of sliding mode control and basic conditions which need to achieve are analyzed. And then, a sliding mode observer of the permanent magnet linear synchronous motor sensorless control system is designed. The related simulation model is built to study the effect of sliding mode observer for rotor position accuracy. The simulation model is implemented to build models of permanent magnet linear synchronous motor vector control system based on sliding mode observer and simulate the control performance of position sensorless control. In the last part, the feasibility of the design scheme is verified by analysis of simulation results.