bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reliability Assessment of Distribution Network Considering Multiple Types of Cyber Disturbances
Authors: Guiping LI , Shuyuan ZHANG 
Published: August 2021

Abstract
The improvement of power grid intelligence depends on the development of communication technology. The wide application of communication technology in power grid has brought new security threats. In order to comprehensively and quantitatively evaluate the impact of external threats and cyber element failureson power supply reliability in the whole process of distribution network operation, reliability state models of different types of cyber disturbances are proposed, the impact of different types of cyber disturbance on the cyber availability is analyzed and a framework of distribution network reliability evaluation considering multiple types of cyber disturbance is constructed. Finally, the simulation test of IEEE33 bus distribution system verifies the feasibility and effectiveness of the proposed model and method.
Infrared time-sensitive weak and small target detection method based on density search and gradient decision
Authors: Liu Chuang , Yang Xiaogang , Lu Ruitao , Gao Fan 
Published: August 2021

Abstract
For detecting infrared time-sensitive weak and small targets in a complex air-ground background, it is easy to be interfered by low signal-to-noise ratio and strong noise. In this paper we proposed an infrared time-sensitive weak and small target detection method based on density search and gradient decision. First, we use adaptive wiener filtering to preprocess the infrared image to reduce noise interference; then, use the density peak search method to extract points of interest, and use the eight-directional gradient method to make decision-making judgments; finally, use the adaptive threshold segmentation method to extract true targets. The experimental results show that this method has good robustness and detection performance for single infrared time-sensitive weak and small target detection in the air-ground background.
Research on optimization of ship’s automatic berthing and unberthing control model
Authors: Zhou Hongmao , Shi Hankun , Zhu Shenchao , Wang Xuelin , Zhang Zhaolun 
Published: August 2021

Abstract
The automatic berthing and unberthing of ships is one of the very important links in the process of ship navigation. Due to the relative increase of interference from external factors such as wind, waves, currents, and the relative increase in system information, the automatic berthing and unberthing operations are more complicated. Traditional control methods have been difficult to meet the technical requirements of automatic berthing and unberthing. This research created a control model for automatic berthing and unberthing, optimized the parameters of the created control model, performed parameter identification on the ship model, and tested the established mathematical model. The test results met the requirements for automatic berthing and unberthing. It provides a good reference value for the future development of automatic berthing and berthing.
Early fault detection for power plant fans based on dynamic neural network
Authors: Zhang Guobin , Du Ronghua , Xin Xiaogang , Zhao Wei , Dang Shaojia , Zhao Song , Yun Pei 
Published: August 2021

Abstract
Early fault detection is increasingly important for the reliable and secure operation of power plant fans. In this paper, we propose an early fault detection strategy for power plant fans based on dynamic neural network. First, the nonlinear autoregressive (NARX) with exogenous inputs network is utilized to predict the behavior of fans by using normal operating data, and the discrete particle swarm optimization (DPSO) is utilized to optimize the hyper-parameters of NARX network to enhance prediction accuracy. Then, the fault alarm strategy is proposed by the prediction deviations and generalized extreme value (GEV) theory. Finally, the proposed method is applied to a forced draft (FD) fan in a coal-fired power plant. Experiment results show that the proposed model has high prediction accuracy on normal operations and produces large prediction errors when a failure occurs. Furthermore, it can detect early faults accurately and timely before the failure occurs.
Research on Yaw Error Detection of Wind Turbine Based on Particle Swarm Optimization
Authors: Zhang Xinyue , Yang Chenghu , Li Xinrui , Yan Daqiang , Li Hai 
Published: August 2021

Abstract
Yaw system is an important part of the wind turbine, one of its main functions is to automatically face the wind when the wind turbine is in normal operation, to ensure that the engine room is facing the wind direction, so that the wind turbine can make efficient use of wind energy. However, the yaw system can not guarantee the accuracy at all times, which leads to the wind deviation. Too large deviation of wind energy not only reduces the efficiency of wind turbine using wind energy, but also leads to abnormal wear of equipment parts, which is not conducive to the normal operation of the unit. In this paper, a wind turbine deviation detection algorithm based on SCADA data is proposed. The detection algorithm mainly includes wind speed segmentation, data fitting, particle swarm optimization and other key technologies. After wind field verification, the algorithm proposed in this paper can effectively detect the wind deviation of wind turbines, and help to improve the efficiency of wind turbines.
Study on Reliability Improvement of Main Steam Isolation Valve Control in Nuclear Power Plants
Authors: Gan Changxian , Wan Tian , Pan Weiwei , Liu Shengzhi , Tang Lei , Li Huahuan 
Published: August 2021

Abstract
There is a safety hazard in the interlock control logic of the second circuit main steam isolation valves of the CPR1000 nuclear power unit. During reactor power operation, any abnormal full-close limit switch signal of valves may lead to a reactor shutdown event or even a Safety Injection of nuclear reactor. In this Paper, the control strategy of the second circuit main steam isolation valves is analyzed and demonstrated, and after Probabilistic Safety Assessment(PSA), a feasible improvement plan is proposed, which effectively improves the control reliability of the second circuit system in nuclear power plants.
Research on Control Design on PMSG Based on LSTM
Authors: Wang Qi , Hu Hongbin , Yuan Shuai , Miao Lifang 
Published: August 2021

Abstract
The traditional control method of permanent magnet synchronous generator (PMSG) needs multiple rounds of tuning and test to ensure the dynamic characteristics of the PMSG to reach the standard. It is complex if there are a large number of PMSGs needs to design parameters of the control loops. In order to simplify the tuning and testing process of the control parameters of the PMSG, a data-driven based control method of a PMSG is proposed in this study. It can fit the standard dynamic characteristics by learning the inputs and outputs of the standard dynamic response curves using the long short term memory LSTM method. Subsequently, the proposed control method can be applied to multiple PMSGs, which is convenient and no staff is involved. Finally, a power system connected with a PMSG is as an example. It demonstrates that the dynamic of the PMSG adopted the proposed control method is same with that of the standard PMSG.
Research on Monitoring System of Cable Joints of Ring Network Cabinet Based on Wireless Temperature Sensor
Authors: Shang Shuning , Liang Guangsheng , Xiao Wei , Ya Hougui , Chen Shuqi , Yu Jie , Chen Zhongbin 
Published: August 2021

Abstract
In this paper, a state monitoring system for the cable joints of the ring main unit is constructed based on the passive wireless temperature sensor. Considering the sensor packaging structure and housing material, a temperature sensor that can meet the monitoring requirements of the T-shaped insulating sheath of the cable joint is designed. Based on the thermal circuit method, the real temperature value of the internal cable joint is calculated by using the outer surface temperature of the T-shaped insulating sheath to provide more accurate data for monitoring and early warning. The background monitoring software of the monitoring system is designed to realize the temperature of the T-shaped cable joint in the ring network cabinet. Online monitoring and abnormal early warning facilitate the operation and maintenance personnel to take timely measures, which can effectively improve the operation and maintenance efficiency of the ring cabinet of the distribution network and ensure the reliability of power supply.
A method of fault detection of casing lead based on CEEMDAN-LMD
Authors: Hao Chenggang , Sun Woye , Zhang Jiguo , Li Kai , Wang Xin 
Published: August 2021

Abstract
The existing regular inspection tests for the deformation faults of the bushing lead have the problem of offline detection and poor sensitivity. In order to effectively extract the high frequency components of vibration for diagnosis and analysis, a new fault diagnosis method for the transformer bushing lead is proposed. This method decomposes the time-domain waveform of the collected ultrasonic echo signal through CEEMDAN, and reconstructs its high-frequency components according to the entropy weight method to obtain a denoising signal, and then performs LMD decomposition of the denoised signal, and decomposes the denoised signal. The PF component is analyzed as the input feature component. The method of ultrasonic inspection of casing lead in this article has good adaptability, can obtain lead fault location results with high precision and good reliability, low hardware cost, and good application prospects.
Hydraulic motor constant low speed characteristics measurement study
Authors: Nie Yueyue , Niu Yuxiang , Xing Keli , Jin Xiajie 
Published: August 2021

Abstract
Due to the special characteristics of hydraulic motors, the minimum stability characteristics are often one of the important characteristics to be considered in hydraulic system applications. In this paper, based on the analysis of the hydraulic mathematical model of the axial piston hydraulic motor, the model of the axial piston motor is established by using AMESim simulation software, and its low-speed characteristic curve is output through simulation to verify the validity and reasonableness of the low-speed characteristic testing scheme of the hydraulic motor. Finally, a hydraulic motor constant low speed characteristic test system is built based on LabVIEW software, and a field verification test of the hydraulic motor constant low speed characteristic is carried out, which provides some engineering reference value for the hydraulic motor constant low speed characteristic test.
Design of defect detection system for semiconductor plastic packaging based on machine vision
Authors: Niu Zanyao 
Published: August 2021

Abstract
At present, the ability of defect detection system to detect the position of semiconductor plastic packaging defects is poor, so a defect detection system of semiconductor plastic packaging based on machine vision is designed. In terms of hardware, based on machine vision technology, the system framework is determined, the camera, lens and light source models are selected, and the detection target image acquisition parameters are determined. In terms of software, according to the target image obtained by machine vision technology, the image is preprocessed, segmented and feature extracted to identify and detect the target image and detect the semiconductor plastic packaging defects. Experimental results: compared with the system selected in this experiment, the design system can accurately detect the defects in the semiconductor plastic packaging and the location of the defects.
Changes of Urban Greenness Based on Sentinel Data and Landsat Data
Authors: Bi Xinrui 
Published: August 2021

Abstract
With the rapid growth of the global economy, environmental resources have also been severely consumed and destroyed. With the rapid growth of China’s economy, domestic environmental pollution and environmental damage have become increasingly serious. In order to understand the changes in the urban greenness of Chinese cities, the changes in the urban greenness of coastal cities in China in the past five years have been explored by using Landsat satellite remote sensing image data from multiple periods since 1973. The reason for choosing coastal cities as the research objects is that the coastal cities have relatively developed economy and have certain demonstrative significance for both themselves and the development of inland cities. This article first popularizes the domestic urban environmental conditions and knowledge of remote sensing technology, and then analyzes the process of obtaining urban greenness sentinel data and Landsat data of coastal cities from remote sensing data, and finally analyzes the urban greenness of coastal cities in the past 5 years. The increase change and the average increase change are analyzed and compared, and corresponding conclusions are given based on the analysis results.
Simulation Modeling Practice on Occupant Evacuation in a Medium-sized Supermarket
Authors: Han Tingting , Chen Dong , Chen Leiyu 
Published: August 2021

Abstract
The research mainly focused on the effect of staff density and exit conditions on total evacuation time. The results showed that with the increase of staff density, evacuation time often increases non-linearly. The function equation of evacuation time and number of occupants in case A was obtained through computer simulation. The augment of exit number or total export width can reduce the total evacuation time to improve evacuation efficiency. While, if the number of evacuees reaches to a certain value, evacuation time may increase non-linearly after being affected by the internal structure and the random distribution of occupant. Export position also has impact on total evacuation time. The results of the simulation have guiding significance on the design of building structures and personnel evacuation in emergency.
Routing in Delay-tolerant network Based on Nodes’ Sociality
Authors: Tan Long , Men Zixuan 
Published: August 2021

Abstract
To solve the problem of low ratio success delivery, long latency caused by the rapid dynamic change of network topology, limited node buffer, large amount of data transmission and large user population density in delay-tolerant network (DTN). This paper propose a routing algorithm in DTN based on nodes’ sociality. In this paper, contact history was used to determine the node link quality; Markov model was used to predict the node position based on the nodes’ movement track; according to nodes’ social similarity to divide community, then calculated node betweenness centrality. Finally, the best forwarding nodes for message transmission were determined. Besides, to increase the ratio of successful delivery, message delivery probability in the relay node’s buffer was calculated. Experimental results show that compared with traditional routing algorithm, the proposed algorithm performs better on the delivery ratio and average end-to-end delay.
Research on key Technologies of 5G Mobile Communication D2D
Authors: Jin Jin , Zhao Lipeng , Zhang Guoquan , Zhang Shenguo , Jiang Kun 
Published: August 2021

Abstract
As one of the main technologies of 5G, device-to-device (D2D) technology directly transmits data between mobile terminals in the adjacent area, and there is no need for base station relay equipment to transfer, so as to realize high data rate transmission, improve communication capacity, reduce transmission delay, and make full use of wireless spectrum resources. With the support of D2D technology, cellular wireless communication can be avoided between devices, so that wireless communication can be realized without occupying the bandwidth resources. In this paper, with the support of D2D technology, firstly, the transmission path optimization of D2D technology is realized by artificial swarm algorithm. Secondly, the simulation is carried out by MATLAB software. Finally, the path optimization of D2D communication is realized by simulation, and the test results are compared and analyzed.
Research on ocean current visualization method based on particle
Authors: Dong Yong , Huang Binghu , Wang Fuyuan , He Yawen 
Published: August 2021

Abstract
NetCDF network general data format is a common data format used to store meteorological data such as ocean current field. However, the ocean current data in NetCDF format can not be read directly on the web for dynamic visualization. To solve this problem, this paper takes the Pearl River Estuary area as the research area, adopts the sparse algorithm based on local Moran’s I index and improved point center buffer to dilute the ocean current data, converts the ocean current point data into particle data by using the vector synthesis calculation method of ocean current data, and designs specific JSON data structure for data storage. After completing the pre-processing of the visualization data of ocean current based on particles, a dynamic visualization display platform of ocean current particles is built on the Web side, and the JSON data of ocean current is read. The space-time dynamic visualization effect of ocean current data in the form of particles in the format of NetCDF is realized, and the static and intuition problem of ocean current visualization is solved.
Construction of High-standard Farmland Geographic Information System
Authors: Chen Yonghua , Chen JiaWei 
Published: August 2021

Abstract
At present, the management of high-standard farmland is only managed at the county level, and data reporting is done by the county in the form of reports, which cannot form a unified data sharing model, resulting in low efficiency in daily management. The comprehensive management system of high-standard farmland designed in the thesis can completely solve the problem of non-uniform management and provide a comprehensive management, query and statistical summary platform with unified data and intuitive image.
Remotely sensed modelling of urban spatial-environmental health across 32 major cities in China
Authors: Zhang Ping , Sun Yifu , Sun Qiangqiang , Sun Danfeng , Zhang Yongxiang , Li Hong , Li Rui 
Published: August 2021

Abstract
The timely and effective evaluation of spatially-explicit urban PM2.5 concentrations is highly important for an improved understanding of urban environmental health and sustainability in China. However, recent studies examining the spatiotemporal patterns of PM2.5 concentrations has not been comprehensively clarified due to the absence of spatial-detailed urban landscape linkage. In this study, a general non-linear model was developed to depict the non-linear relationship between spatially explicit impervious surface area (ISA) fractions and associated PM2.5 concentrations gradient changes for individual cities from multi-source satellite-based dataset. The comparative results of environmental quality across 32 major cities in China showed that the spatial pattern of urban PM2.5 concentrations is correlated with geographical orientation and socio-economic clusters—high baseline and more balanced states of PM2.5 concentrations are prevalent in North China and the Yangtze delta agglomerations. Temporally, during the period of 2000-2018, most of cities have the path dependency, whereas high concentration of PM2.5 diffused from the original east of ‘Hu-Huanyong Line’ toward some cities in north-eastern, central and western regions. In addition, our study highlights the optimizing regional economic structure and promoting urban greening construction will be of great significance in sustainable urban environmental health management.
Deep Space Exploration Strategy Based on Distant Retrograde Orbits Space Station
Authors: Zhang Yingyi , Zhang Wei 
Published: August 2021

Abstract
To improve the utilization rate of DRO, reduce the cost of human lunar and human mars exploration mission, and exploit space between earth and moon, this paper studied human lunar and mars exploration flight modes based on DRO space station. Firstly, the mission profile of human lunar and mars exploration flight mode based on DRO space station is analyzed by comparing with the direct round-trip lunar flight mode. The human lunar and mars exploration mission can be decoupled into the human space transportation mission and the lunar or mars landing mission by the DRO space station. Then, a flight mode evaluation model is established to analyze and evaluate quantitatively the advantages and disadvantages of the flight modes based on the DRO space station. The evaluation results show that the flight mode based on the DRO space station is a optimal flight mode.
Geological hazard interpretation and hazard evaluation of open pit mines based on Unmanned Aerial Vehicle images
Authors: Ma Jianxiong , Liu Jiwen , Ming Jing , Sang Xuejia 
Published: August 2021

Abstract
Over-exploitation of open-pit mines has caused extensive development of geological hazards, posing serious threats to people and buildings in the area. Based on the UAV tilt-tilt photography technology, this paper generates a real-world 3D model of the study area, taking the molybdenum mine of Songshumao in Yangjiajiaozi, Xingcheng City, Liaoning Province as an example, and combines orthophotography, high-precision DEM data and field geological survey research to establish a geohazard interpretation marker for the study area and interpret various types of geohazards such as landslides, landslides, dangerous rocks, ground cracks and unstable slopes in the study area. Based on the hierarchical analysis method combined with the geological environment characteristics, the geological hazard risk evaluation model and index system were established, and five indexes were selected, including geological hazard range, stratigraphic lithology, slope, elevation, vegetation coverage, etc. The study area was divided into high, medium and low risk zones, and the geological hazard risk zoning map was obtained to complete the geological hazard risk evaluation of the study area.
Effect of multiple extrusion on phase structure and properties of impact copolymerized polypropylene
Authors: Xiaoyan LIU , Dongbo ZHAO , Shoujun DENG , li LI , Hongyi DUAN 
Published: August 2021

Abstract
As a typical multi-component polymer, impact polypropylene copolymer (IPC) experiences the phase structure evolution during repeated processing, and the coarsening of phase domain often occurs. In this work, two IPCs with different molecular weight of rubber phase were compared systemically. The evolution of IPC phase morphology and crystallization behavior after multiple extrusion were studied through scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The materials mechanical properties were tested. Then the influence of rubber phase molecular weight on the phase morphology evolution and the properties after repeated extrusion were discussed in detail. It was found that for the IPC with low molecular weight of rubber phase, the size of rubber phase became smaller and dispersed more evenly with the increase of extrusion times; for the IPC with high molecular weight of rubber phase, the rubber phase size turned to unstable after multiple shearing. The rubber phase size had a complex effect on IPC mechanical properties.