bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Design of Industrial Park Environment Monitoring System Based on NB-IoT
Authors: Chen Zilong , Zang Chunhua , Wang Wenlong , Tang Xubo 
Published: January 2021

Abstract
This paper describes a distributed industrial park monitoring system based on NB-IoT technology. The system uses the STM32 to control the sensors work, and uses the NB-IoT communication module to realize the remote data transmission between the monitor terminal and the network server. This design is different from the traditional monitoring system based on the wide area Internet of Things, and has the advantages of low cost, low power consumption and wide coverage area.
Chaos Analysis of the Output Game Between Multi-role Enterprises in Supply Chain
Authors: Guanhui Wang 
Published: January 2021

Abstract
Based on an analysis on a variety of game models in the supply chain, this paper proposes a multi-enterprise output game model under the circumstances of information asymmetry. This paper compares two types of models from the aspects of function selection, hypothesis parameters and modeling basis, and analyzes the influence of producer's output adjustment speed parameters on the whole supply chain.
Video emotion recognition based on Convolutional Neural Networks
Authors: Li Chen , Shi Yuliang , Yi Xianjin 
Published: January 2021

Abstract
The existing video sentiment analysis methods only obtain features from the spatial and temporal signals of the video for sentiment classification, and cannot solve the difficulty of not knowing which emotion contributes the most to the entire video sentiment analysis in the video sentiment analysis. To solve this problem, a neural network with video frame weight vector is proposed. First, the video frame feature is obtained through the reel neural network, and then the weight vector layer is used to calculate the weight of the feature, and finally the frame feature with weight is put into the LSTM Training to obtain a video sentiment analysis model. We verified on the BAUM-1s data set. The results show that this method is better than existing methods in accuracy.
Research on phishing webpage detection technology based on CNN-BiLSTM algorithm
Authors: Zhang Qiao , Bu Youjun , Chen Bo , Zhang Surong , Lu Xiangyu 
Published: January 2021

Abstract
The rapid development of the Internet has also brought opportunities for some illegal elements. Network attackers steal sensitive information from victims through phishing webpages to obtain economic benefits. Currently, the commonly used detection methods for phishing webpages, based on blacklist detection and webpage content feature detection, have the problems of being unable to detect newly emerging phishing webpages or requiring manual extraction of webpage features. Therefore, researchers have used Convolution Neural Network (CNN) to detect phishing webpages by automatically extracting URL features. However, its method has some limitations: (1) The memory is limited when the URL is transformed into the feature matrix, and the embedding vector of new words cannot be obtained or the effective information of sensitive words is lost; (2) the long-distance dependent feature of the URL cannot be obtained. In response to the above challenges, we proposes a phishing detection method based on CNN and Bi-directional Long Short-Term Memory (Bi-LSTM) based on existing work: based on sensitive word segmentation-- comprehensively using two existing URL segmentation methods before converting URL into eigenvector matrix; adding Bi-LSTM on the basis of convolutional neural network to obtain URL long-distance dependent features. Experimental results show that this method can achieve high accuracy, recall rate and F1 value.
WeChat Official Account Analysis of Music Users
Authors: Chen Gen-Fang 
Published: January 2021

Abstract
The purpose of this study is to explore the user's attention to music knowledge in our media era. The data of this study come from a WeChat official account called "learning music", which has more than ten thousand official account users. Time correlation analysis and statistical analysis were used to evaluate the data. The results are as follows: the official account of music information is mainly concerned with new users. The new attention of the daily users is relatively stable, and the daily users' use of official account numbers and reading pictures and text information are relatively random. The proportion of male to female users is close to the official account number. Compared with the proportion of the population, the female users' attention to music information is relatively high. The majority of users in simplified Chinese are concerned, which is related to the location of official account. Android system and apple system are the main terminals used by users.
Research on ADN “source-grid-load” coordinated operation index system
Authors: Liao Zheng , Li Xiaotian 
Published: January 2021

Abstract
With the large-scale access of distributed generation (DG), problems such as harmonic pollution and increased access point voltage have been brought to the operation of the distribution network. The active distribution network (ADN) integrates a wealth of controllable resources to promote network optimization and green energy consumption. At present, the research on the “source-network-load” coordinated operation index system focuses on a certain direction, and does not consider the multi-dimensional influencing factors. Based on this, this paper starts the research, from the perspective of safety, economy, environment and coordination. In four aspects, the PCA algorithm is used to determine the evaluation index, and the AHP model is used to establish the evaluation system, and the calculation method of each index is explained and calculated to deepen the understanding of the evaluation system established in this article.
Dynamic Security Assessment Method of Power System Based on Improved XGBoost
Authors: Ren Jihong 
Published: January 2021

Abstract
With the deployment of wide-area measurement systems (WAMS) equipment, dynamic security assessment (DSA) based on artificial intelligence (AI) has more and more advantages. For the power system, the number of transient stable cases is much larger than that of unstable cases, which leads to insufficient learning of unstable cases and affects the evaluation effect of the model. In addition, during the stability assessment process of the power system, the misjudgment cost of unstable case is much higher than that of stable case. Based on the above two points, we proposed a DSA method of power system based on improved XGBoost. The proposed method introduces the weight adjustment factor into the loss function to balance the quantity variance of two type cases and the difference of misjudgment cost, which greatly reduces the misjudgment rate of unstable samples. The test results on IEEE 16-machine 68-bus test system and IEEE 50-machine 145-bus test system show that the proposed method can have higher recognition of the unstable samples and can be applied to DSA.
Numerical simulation and experimental analysis of vibration characteristics of heterogeneous sheet structure with adhesive
Authors: Genglin Tang , Peng Qian , Wenfeng Zhu , Yuanhui Li 
Published: January 2021

Abstract
The use of steel-aluminum heterogeneous sheets and its adhesive-coated hemming process for cover parts helps to realize the lightweight of the car body, and its vibration characteristics greatly affect the NVH characteristics of the vehicle. Traditional cover parts vibration characteristics research ignores the influence of adhesives. Facing the higher performance of lightweight cover parts systems, it is necessary to establish a “sandwich”; multi-material structure model consisting of aluminum outer sheet-ductile structural adhesive layer-steel inner sheet. Based on the typical straight edge-flat surface unit structure of cover parts, this paper established a calculation model for the vibration characteristics of steel-aluminum heterogeneous sheet adhesive structure, and the effect of adhesive thickness is quantified through experimental verification. The results show that the natural frequencies of the finite element calculation model and the experimental model are highly consistent in the first two modes, and the first two natural frequencies become larger as the thickness of the adhesive increases. The shell element of finite element calculation model based on the laminated sheet vibration theory can effectively simulate the calculation of the first two modes of the steel-aluminum heterogeneous sheet adhesive structure.
Research on RF antenna for detecting corona discharge of electrical equipment
Authors: Zhang Bin , Hei Guoyu 
Published: January 2021

Abstract
In power systems, corona discharge often occurs, which is a common phenomenon. If it occurs in electrical equipment, then hidden dangersexist, such as poor contact between metal fittings of insulators and electrical equipment, insulation performance degradation due to equipment agingand strand breakage of transmission lines. These dangers may lead to further serious accidents. So, it is very important to detect and eliminate the hidden dangers. Because corona discharge will radiate radio frequency (RF) electromagnetic waves to the surrounding space, the detection of corona discharge can be realized by detecting RF electromagnetic waves. In this study, two miniaturized antennasare designed to detect corona discharge in electrical equipment. These antennasare rectangular spiral antennaand Hilbert antenna. Through simulation and comparison, it is found that Hilbert antenna unit is the best and the final structure is the 6 order Hilbert antenna. The final size of this antenna is 100 mm*100 mm*1.6 mm, which is portable and lightweight.
Household smart cat litter box
Authors: Wang Lihao 
Published: January 2021

Abstract
With the change and development of the times, more and more young people live alone in the cities, and with the pressure of work, they are often lack of company. Cats are docile in nature, like keeping neat and tidy, and don’t need too much time with their owners, so keeping pet cats is more convenient for most of people. Therefore, pet cats are very popular among young people, more and more young people start to keep pet cats as companions. In addition, with the improvement of people’s living standards, the average family can also afford to raise a cat. Whether as a companion to a child or a member of the family, pet cats are also very popular in ordinary families.
According to the surveys, most families now have some pets. But obviously it’s a problem for these families to deal with the excrement of the cats. Because of the heavy smell, every time shoveling the feces will cause a lot of trouble to people. What’s worse, the smell of feces will evaporate in the air, causing air pollution. In order to solve the above problems, we designed a smart litter box that can separate and completely seal the cat feces. It solves the problem of the difficulty in handling cat feces and the heavy smell of cat feces, and can maximize the utilization of household space. Through the fully automated function and effective human-computer interaction function of this litter box, people can greatly save the time and energy spent in processing cat feces.
Research on the Design of Sound Insulation Performance of Isolating-sound and decoupled tile Based on Local Resonance Membrane Material
Authors: Li Zongji , Zong Fangyong , Zhang Jian 
Published: January 2021

Abstract
In order to enhance the acoustic stealth performance of the underwater vehicle, we combine the resonance sound absorption and vibration suppression performance of the sound-absorption coating and the low frequency sound insulation performance of the local resonance membrane material, a new type of isolating-sound and decoupled tile with low-frequency sound insulation, sound absorption and vibration suppression performance is designed, and an acoustic enclosure composed of isolating-sound and decoupled tile is established. Research shows: the isolating-sound and decoupled tile cell has good sub-wavelength sound insulation ability, and the average sound insulation in the 100-1000Hz frequency band is 47dB. The acoustic enclosure composed of it can effectively isolate the reverberation sound field in the enclosure. Compared with the acoustic enclosure composed of Alberich sound-absorption coating, the average sound insulation has been increased by about 19dB.
A Detection Method of Dense Harmonics/Inter-harmonics Based on Improved All-phase Time-shifting Method and ZoomFFT
Authors: Zhang Qing , Cai Xingyue , Li Wenbo , Liu Zhaorui , Meng Xueqing 
Published: January 2021

Abstract
Aiming at the complex situation of intensive harmonics/inter-harmonics in power signals, this paper proposes an analysis method based on improved all phase time shift phase difference method and ZoomFFT. Firstly, the Hankel matrix of the input signal is constructed, and the TLS-ESPRIT algorithm is used to obtain the frequency components in the signal. The relationship between the peak spectral line and the frequency offset in the all phase time shift method is derived. The amplitude information of the input signal is calculated. The phase information of the input signal is obtained by analyzing the “phase invariant” characteristic of the all phase FFT spectrum. The frequency interval of adjacent frequencies is used to judge whether there is density. If there are intensive harmonics/inter-harmonics, TLS-ESPRIT method is used to calculate the center frequency of the dense spectrum and construct a complex analytic band-pass filter to improve the ZoomFFT method to extract the frequency and amplitude information of the signal at the dense spectrum; If there is no intensive harmonic/inter-harmonic, the improved all phase time shift method is used to extract the parameters of the input signal. Simulation results show that the proposed algorithm can effectively and accurately extract the frequency, amplitude and phase parameters of dense harmonics/inter-harmonics under the conditions of multiple dense spectrum, fluctuation of fundamental frequency and noise interference.
A low stray inductance laminated busbar for series-parallel capacitors
Authors: Yannan GUO , Peng SUN , Yumeng CAI , Zhibin ZHAO 
Published: January 2021

Abstract
In the dynamic characteristics test circuit for high-voltage and high-power power electronic devices, the laminated busbar is the main connecting component. The stray inductance of the laminated busbar is one of the key factors that affect the accuracy of the dynamic characteristics. Therefore, a low stray inductance laminated busbar for series-parallel capacitors is proposed, from the perspective of reducing self inductance and increasing mutual inductance. Through finite element simulation, the result of extracting the stray inductance of the laminated busbar is 4.16nH. Compared with the most basic laminated busbar, this stray inductance is very small.
Simulation Analysis on The Influence of Temperature and Stress in The Plastic Processing of Crystal Germanium
Authors: Bi Jiao long , Shi Guang feng , Shi Guo quan , Gao Ji yu 
Published: January 2021

Abstract
Crystal germanium has the characteristics of high hardness and brittle quality. It is a common material for infrared optical parts. In order to explore the mechanical properties of germanium crystals in plastic processing and the influence of temperature on cutting, FEM software was used to conduct micro cutting simulation on the ultra-precision turning process of germanium crystals, and the cutting force, temperature and cutting energy in the cutting process were analyzed. The results show that the main cutting force and cutting resistance decrease with the increasing of the temperature. By calculating the unit cutting force and the unit cutting resistance, the change of cutting energy is reflected indirectly. By means of normalization of cutting force, the specific gravity of stress and temperature to the cutting process at different temperatures is obtained.
Design and analysis of retractable structure of new quadrotor landing gear
Authors: Xin Huang Bing 
Published: January 2021

Abstract
With the development of equipment level, the requirements for the compact-ness and light-weight of UAV become more and more stringent. In order to solve the problems such as the weight and large volume of the landing gear of the existing four-rotor aircraft, this paper developed a new four-rotor unmanned helicopter landing gear retractable structure based on the existing landing gear. The release process and retractation of retractable structure of the new landing gear are described, and its motion form and attitude are introduced in detail. In this paper, the stress of high strength flexible rope during landing gear releasing and re-tracting is analyzed, and the mathematical model is established. Adams software is used to simulate and analyze the force state of the landing gear leg when the rope is pulling at a constant speed. The results of the dynamic simulation and mathematical model are consistent, that is, the maximum force when retracted to 90° is about 30N (for a single wing). Finally, the finite element simulation software Ansys Workbench was used to carry out strength checking and deformation analysis of the wing, and the rationality of the designed me-chanical structure was verified. The research results of this paper provide a certain basis for the development of landing gear of four-rotor unmanned helicopter.
Effects of physical parameters and time-delay coefficients on the amplitude and frequency bandwidth of saturation controller for a nonlinear beam vibration
Authors: Dai Han , Zhao Yanying 
Published: January 2021

Abstract
This paper is focused on the effects of the physical parameters for saturation control bandwidth and the time-delay coefficient for the saturation control stability. The approximate analytical solutions are obtained when the primary external resonance and 1:2 internal resonance occur simultaneously. The effects of amplitude of excitation, nonlinear feedback coefficients and nonlinear coefficients on saturation control are investigated. It is shown that nonlinear feedback coefficients can enlarge the effective saturation control bandwidth and enhance the dynamic vibration absorber’s suppression. Two nonlinear coefficients enhance the system’s nonlinear phenomenon and remain the same saturation control regions. For the time-delay coefficient, the system begins to appear unstable saturation control regions with only a little time-delay. The increasing time-delay coefficients can enlarge the unstable saturation control regions, it should be avoided.
Effect of the stator tooth thickness on flow characteristics of high shear mixer
Authors: Kwon Cholu , Kim Kwangchol , Pak Unsong 
Published: January 2021

Abstract
Due to the complexity of flow field in high shear mixer, it is very difficult to measure the flow field in full three-dimensional. CFD simulation has become a powerful means in mixer research. In this study, large eddy simulation (LES) was used to simulate the single-phase flow field of a pilot scale in-line high shear mixer with ultra-fine teeth. The research results show that with the increase of the stator tooth thickness, the turbulence intensity and eddy current intensity around the outermost stator increase slightly, and the shear rate area with a larger value change slightly. This means that the stator tooth thickness has a slight effect on the flow field. These results provide important guidance for the design and optimization of high shear mixer structure.
Quantitative research on the contribution of demand-side response to the promotion of renewable energy consumption
Authors: Xiang Meng , Ji Guangya , Zou Yanhui , Dong Zichao , Shao Zhu , Tang Xingzhu 
Published: January 2021

Abstract
Current demand side resources gradually become an important part of promoting renewable energy given, using price, taxes, subsidies and other economic mechanism, encourage users to change electricity behavior, complete with the maximization of expected load curve fitting, to achieve the peak cut, or peak adjustment, to maximize the utilization of renewable energy power generation. Based on the reasonable classification and definition of user types and demand-side resources, this paper constructs a grid load influence degree model of compatible demand-side resources, and quantitatively studies the contribution degree of demand-side response to promoting renewable energy consumption.
An Adaptive Predictive Control Method Based on State-space Model
Authors: Luo Xiaosuo 
Published: January 2021

Abstract
An adaptive state-space model predictive control strategy is proposed for complex industrial processes with nonlinear, time-varying and constrained characteristics. The state-space model obtained by on-line identification algorithm is used as the system model, and the indirect form is used to design the adaptive predictive controller. The controller includes quadratic programming solution to the constraint problem. The effectiveness of the proposed control strategy is verified by the simulation experiment of 2-CSTR process control.
Research on Coordinated Control Strategy of Energy Storage Participating in Primary Frequency Regulation Considering Frequency Deviation Change Rate
Authors: Yang Bo , Weng Liguo , Li Yuelong , Zhang Yanghui , Zhou Chen 
Published: January 2021

Abstract
In order to further improve the performance of primary frequency modulation (PFM) by battery energy storage, a new control strategy is proposed. By analysing the characteristics of virtual inertia response and virtual droop control, the artificial dead zone of energy storage participating in frequency modulation is set based on virtual inertial control to make it respond quickly and improve the characteristics of energy storage to suppress frequency deviation change rate; In this paper, the remaining energy and load disturbance of the energy storage battery are taken as the double inputs, and the fuzzy control strategy is used to derive the function relationship between the virtual droop coefficient and the two inputs to ensure that the charging and discharging power of the energy storage battery is suitable for the actual needs. The load change rate is used to predict the load change at the next moment. Based on this, the coefficients of virtual inertia control and virtual droop control are determined, and the output coefficients of both are optimized to achieve the optimal frequency regulation effect. Three evaluation indexes are proposed to evaluate the control strategy in this paper. Finally, the simulation model is established in MATLAB/Simulink and the case study is carried out in a regional power grid. The proposed strategy can effectively improve the primary frequency regulation of power grid and has positive significance for maintaining energy storage battery.
Study on connection quality of assembled cam after hydraulic expanding
Authors: Lin SONG , Lianfa YANG 
Published: January 2021

Abstract
The cam is an important part of engine exhaust opening and closing. The assembled cam has completely replaced the traditional integrated cam. In this paper, several common methods for assembly effect detection of assembled cam are summarized, and five methods are analyzed and commented from the aspects of measurement form, data form, destructivity, usage scenario and economy. To measure the contact area and residual stress of the fitting surface with the assembled cam, a suitable method is selected, and the research direction is determined.