bluuebunny/crossref_metadata_2025 huggingface dataset:
Millimetre wave antenna for biomedical applications-a review
Authors: Mohan Nadar Akila P , Indhumathi K
Published: May 2023

Terahertz represents the portion of electromagnetic wave between the microwave and IR region. Recent research has been focused on the application of Terahertz waves in biomedical applications such as cancer detection. The current diagnostic methods in cancer treatment involve imaging to MRI and biopsy. Due to the low photon energy that terahertz possess, there are no health threats caused in contrast to traditional methods. Cancer cells can be detected by monitoring the blood supply to the affected tissues and water level in the local tissues. This can be diagnosed using Terahertz imaging. THz radiation can be generated and detected using various commercialized systems. On analysis of various literatures, it is observed that Meta material antennas will be the suitable candidate to enhance the existing terahertz spectroscopy techniques since it has better focusing capabilities. This paper reviews the various implementation techniques of an antenna in THz range. The design and properties of the antenna are also investigated.
Research and Implementation of USV by Adaptive Collision Avoidance Algorithm in Mixed Scenarios
Authors: Hu Pei Lin , Xiao Jin Chao , Xiong Jun Feng , Liu Jin Qing
Published: May 2023

During the mission of the USV (Unmanned Surface Vehicle), there may be some static or dynamic obstacles on the pre-planned track that are not displayed on the ground station. To avoid these obstacles in time, a model of DCPA (distance to the closest point of approach) between the USV and the obstacle is proposed, which is used to plan the speed of the USV, and adaptively accelerate and decelerate can safely avoid dynamic obstacles. We solved the problem of target unreachable and heading change optimization by planning the heading at IAPF (improved artificial potential field) in the process of sailing, which can effectively avoid static obstacles and respond to collision avoidance in emergencies. The collision avoidance planning outputs a set of behavior vectors (speed, heading), and hands it over to the USV controller to control the navigation of the USV. In this study, an adaptive speed and heading planning method is used to improve the collision avoidance ability of the USV in the mixed scene of dynamic and static obstacles. Through multiple launching experiments, the actual collision avoidance effect of the method is verified, and the safety and reliability of the USV application requirements are met.
PID parameter tuning based on improved particle swarm optimization algorithm
Authors: Shi Peidong , Jianchuan  , Xianyu
Published: May 2023

To address the shortcomings of the particle swarm algorithm in solving the PID controller parameter optimization problem in the late stage, an improved particle swarm algorithm is proposed for solving the problem. The particle swarm algorithm is optimized by introducing a nonlinear decreasing inertia weight adjustment strategy so that the pre-flight speed of the particles does not drop too fast, thus balancing the global search ability of the particles with the local search ability and avoiding falling into a local optimum. Simulation experiments were conducted in Matlab/Simulink using the standard PSO, ZN formula method, and the improved PSO, respectively. The results show that the improved algorithm enhances the stability, convergence speed, and search accuracy of the PID parameters with better performance indicators.
Automatic cloud detection method for optical remote sensing images combining channel attention mechanism and multi-feature fusion
Authors: Tan Shuyang , Zhang Jiaxing , Yang Jiaxin , Zhang Zheng
Published: May 2023

Cloud detection is a crucial step in remote sensing image pre-processing, but there are still issues such as cloud miss detection and false detection. Therefore, this work suggests a multi-feature fusion and channel attention mechanism combined approach for automatically recognizing clouds. Based on DeepLabV3+, to make the feature extraction faster and more accurate, a lightweight network structure MobileNetV2 is used as the backbone network. To effectively distinguish snow and clouds, channel attention is added to the low-level semantic information, which makes the network more able to focus on essential features. Meantime, mid-level semantic features are added to the decoder module to make use of more abundant features, thus reducing the false detection of mist. Experimental findings on the GF1 WHU dataset demonstrate that the method’s detection accuracy is improved by 2.1% when compared to DeepLabV3+, and it performs well in the cloud detection job of optical remote sensing images.
Surface Mounted Production Line Capacity Prediction Based on Data Driven
Authors: Zha Shanshan , Shao Hao , Zou Wenzhong , Li Luyang , Chu Yiqun
Published: May 2023

Capacity prediction of surface mount production lines is important for improving productivity, dynamic production scheduling, and optimizing production structure. An integrated mutual information-cuckoo search-extreme learning machine (MI-CS-ELM) prediction model is proposed for the impact of nonlinear and high-dimensional features of surface-mounted production lines on capacity. Firstly, the features affecting the production capacity are ranked based on the mutual information method, and the predictive input data set is reconstructed. Secondly, the input parameters of the prediction model are adjusted by the cuckoo search algorithm and the capacity prediction model is built based on an extreme limit learning machine. Finally, the rationality of the proposed method is verified by an example to guide capacity planning and production scheduling optimization.
Research on the stress intensity factor of crack on the finite width plate with edge damage based on the finite element method
Authors: Yuan Hong , Zhang Hao
Published: May 2023

In aircraft structure maintenance, when we remove edge cracks of some structures, such as aircraft skin, or frame edges, the removal depth and radius affect the stress intensity factor of the crack tip, thereby affecting the service life of the structure. In this paper, we use the finite element method to calculate the crack stress intensity factor of the finite width plate and compare it with the engineering analysis method, which proves the effectiveness of the finite element method. We further research the influence of the crack stress intensity factor with different edge damage depths and radii of the finite width plate, which will provide a reference for aircraft structure edge damage tolerance analysis in engineering.
Design and Research of Robot Image Perception System Based on Artificial Intelligence
Authors: Guo Lina , Cheng Kun , Jia Lianqin
Published: May 2023

In recent years, with the rapid development of science and technology, the performance and functions of traditional robots have gradually failed to meet people’s needs for production and life, and the development of robots has gradually become intelligent and networked. Among them, as the core technology of mobile robot positioning and navigation, environment perception technology has always been the focus and hot research issue in the field of robotics. This paper mainly studies the design of a robot image perception system based on artificial intelligence. In this paper, a tetrahedral robot image-sensing system based on a panoramic camera is proposed and designed, and a U-net convolutional image semantic segmentation network is designed.
Path Avoidance System of Intelligent Robot Based on Computer Vision
Authors: Ren Hongfei
Published: May 2023

At present, obstacle avoidance technology is widely used in the military field, scientific detection, traffic control, industrial manufacturing, medical service, and many other fields, and various machines with autonomous navigation and obstacle avoidance capabilities have been used to varying degrees, thus replacing some human daily production activities and bringing many conveniences to people’s lives. The key to autonomous obstacle avoidance is to obtain the direction information of the obstacle in its direction of advance in real time, which is also the precondition of obstacle avoidance system in obstacle avoidance path planning. In this paper, an intelligent robot path avoidance system is designed based on computer vision (CV) theory. The binocular vision ranging experiment verifies that the system has a less ranging error and can effectively detect the location of obstacles within a certain range, and the success rate of intelligent robot avoidance of obstacles reaches more than 96%, achieving a good avoidance effect.
3D Reconstruction Method of Carbon Fiber Reinforced Plastics Components Based on Pre-calibration Measurement Pose
Authors: Zhang Jianhui , Wang Tianao , Chen Suming , Yue Shan , Wang Guolei
Published: May 2023

According to the surface reflection characteristics of carbon fiber reinforced plastics and the geometric characteristics of aircraft panel parts, a robot automatic measurement system based on line laser scanning is designed. The selection criteria of measurement pose and the pre-calibration method of measurement pose based on a laser tracker are given. A 3D reconstruction method of global stitching of large-scale parts based on pre-calibration measurement pose is proposed, Finally, the correctness and effectiveness of the proposed method are verified by measuring typical samples with a prototype system.
Simulation Study on Safe Distance between Crane Boom and High-Voltage Line Based on Electric Field Intensity
Authors: Luo Xi , Yin Mengqi , Xu Ce , Tang Guanrong
Published: May 2023

Aiming at the safety accident caused by the close distance between the crane arm and the high-voltage line when the crane is working near the high-voltage transmission line, this paper proposes a simulation model of the electric field intensity distribution of the high-voltage transmission line. First, through the simplification and equivalent treatment of the high-voltage line, the simulation modeling, and analysis of the electric field around the high-voltage line are carried out. Then, the theory of solving the electric field intensity of any point around the high-voltage line based on the charge simulation method is deduced, and the conclusion that the electric field intensity at the equal distance of the high-voltage line is approximately equal is obtained. Furthermore, the influence of the crane on the electric field strength of a high-voltage line is analyzed, and the linear correction function of electric field strength is obtained. Based on the research in this paper, the field strength sensor can be used to obtain the value of the electric field strength, calculate the distance between the crane and the high-voltage line, and make a safety warning response. The simulation results verify the feasibility and effectiveness of the proposed model and method.
Rerouting planning of suborbital debris hazard zone based on reinforcement learning DDPG
Authors: Chen Wantong , Cheng Zhiye
Published: May 2023

Aiming at the debris hazard area caused by the explosion and disintegration of the suborbital vehicle, the plane convex hull divide and conquer method is used to process the physical boundary which is in accordance with the air traffic control rules. On this basis, a new method of civil aircraft rerouting planning based on reinforcement learning DDPG algorithm is proposed. According to the state-action space DDPG algorithm, the reward function is optimized to achieve the effect of reasonable routing. With the increase in training times, the reward curve gradually becomes stable and converges in a certain time step, which verifies the effectiveness of the route change planning method.
A Mobile Design of an Inverter Circuit based on Arduino and SIMULINK
Authors: Chen Wanbo
Published: May 2023

Nowadays, with the development of electric engineering, the majority of current civilian sources are portable, such as the battery. However, most of them are only able to output DC without a power inverter, so a power inverter must be applied. To realize the reduction of the volume of the inverter, this solution is based on the combination of MCU (microprogrammed Control Unit) and traditional inverter circuit, because of the limitations of the breadboard. The rationale is that by changing the state of thyristors with a certain frequency by input pulses from an MCU, the current direction flow is changed through the inductor. In this way, alternating currents are created. This design is first verified in SIMULINK, where the chosen MCU for physical construction is the Arduino series.
Diode-Pumped Intracavity OPO KTP/YAG:Nd3+ laser for Cr2+:ZnSe pumping
Authors: Smirnov I V , Zverev P G , Sirotkin A A
Published: May 2023

Electro-optically Q-switched side-pumped diode-pumped KTP/YAG:Nd3+ nanosecond laser system with an intracavity collinear optical parametric oscillation was proposed as a pump source for Cr2+:ZnSe laser. Energy parameters of Cr2+:ZnSe laser were investigated with respect to the wavelength of the pump laser. Under optimal conditions, pumping with laser pulses with an energy of 10.5 mJ and a duration of 7.2 ns at a wavelength of 1950 nm allowed to obtain 3.2 ns pulses at a wavelength of 2494 nm with slope optical-to-optical conversion efficiency of 5.5%.
High efficiency in-band pumped Tm- and Ho-doped 2-μm solid-state lasers
Authors: Antipov O.L.
Published: May 2023

The expansion of laser sources operating at 2-3 μm is motivated in large by strong absorption in atmospheric gases, liquid water, and plastics, critical for applications in remote sensing, soft and hard tissue surgery, and materials processing. 2-μm novel solid-state lasers based on Tm3+-doped ceramics (Lu2O3 or Y2O3) or YAP crystals in-band pumped by a fiber laser at 1670 nm are presented in this report. CW, actively or passively Q-switch operations of the Tm3+-doped lasers are described. The Tm3+ laser characteristics are compared with parameters of an in-band fiber-laser-pumped Ho3+:YAG laser. The 2-μm output of the lasers are used to pump the Cr2+-doped ZnSe or CdSe crystals. The lasers based on the Tm3+:Lu2O3 ceramics and the Tm3+:YAP crystal are also used as pump sources for mid-IR optical parametric oscillators (OPOs) or second-harmonic generators (SHGs). The high-efficiency oscillations are obtained at 3.8-4.1 μm in the OPOs based on a fun-out PPMg:LN; the SHGs provided the repetitively-pulsed radiations at 970-983 nm.
Condensate States of Atomic Bose-Fermi Gas Mixtures
Authors: Bolech C. J. , Clayton Peacock J. , Ljepoja Aleksandar
Published: May 2023

We report on the different types of condensates possible in two-component atomic gas mixtures in one dimension involving both bosons and fermions. When the interactions are attractive, we show there is a rich variety of coherent ground-state phases that vary with their intrinsic and relative strength. We avoid any artifacts of lattice discretization by developing a novel implementation of a continuous matrix-product-state ansatz for mixtures that we first show to systematically converge towards exact results for the Lai-Yang-model integrable case.
Research on Intelligent Identification of Magnetizing Inrush Current based on Empirical Modal Decomposition
Authors: Duan Pan , He Ya , Zhang Lianfang , Shi Yingqiao , Yu Yuxin , Wan Haibo
Published: May 2023

The accurate identification of the converter transformer magnetizing inrush current can ensure the safety of the operation of the UHV DC transmission system. In the differential protection of the converter transformer, it is extremely hard to distinguish between the excitation inrush current generated when the transformer is closed and the Fault current due to internal fault, which leads to frequent misoperation of the transformer protection to the extent that the transformer access fails. This paper proposes a current identification model based on empirical modal decomposition (EMD) and probabilistic neural network (PNN) algorithm with particle swarm (PSO) optimization. The EMD algorithm decomposes the current waveform, and the eigenmode functions (IMFs) of the three highest correlation bars are selected. The energy, cliffs, and standard deviation of the IMFs are extracted as the original waveform eigenvectors.
Research on power balance control method of microgrid energy storage unit
Authors: Fu Yongjun , Guo Xiaoyu , Jiang Chaopeng , Yu Hao , Liu Yujia
Published: May 2023

In the isolated island operation of microgrids, affected by the different equivalent circuit impedance between distributed generators, the traditional droop control cannot evenly divide the reactive power borne by distributed generators according to the different line impedance. Therefore, firstly, the reasons affecting power sharing are analyzed, and then an improved droop control method based on traditional droop control is proposed; that is, the time change rate of voltage is used as the droop variable, and a voltage recovery mechanism is added to the reactive droop controller, in order to adjust the reciprocal of voltage to zero in the steady state, so as to stabilize the voltage. Aiming at the problem that the droop controller cannot always realize the equal distribution of reactive power, a voltage compensation link suitable for improved droop control is designed and added to eliminate the line impedance difference between distributed generators and improve the accuracy of reactive power distribution. Finally, the effectiveness and feasibility of the proposed control strategy are verified by building a “wind light storage load” microgrid simulation model on the MATLAB / Simulink platform.
Time Interval Analysis on Calculation of Temperature Rise Rate of Lithium-ion Battery Thermal Runaway
Authors: Shi Xuewei , Dong Wenqi , Gao Fei , Guan Yibiao , Liu Jialiang , Yang Junfeng , Yang Tian , Liu Shiyang
Published: May 2023

The battery temperature rise rate is an important monitoring parameter to judge the safety state of the lithium-ion battery. However, there is little research on how to calculate the value of battery temperature rise rate, and there is a big difference in the temperature rise of battery calculated at different intervals, which affects the accurate judgment of the battery safety state. Therefore, in this paper, the temperature change of the battery surface during the thermal runaway process at the 0.5C rate is studied, four different temperature rise calculation intervals, such as 1s, 10s, 30s, and 60s, are set, and four different curves of temperature rise versus time of the battery are obtained. The value of the temperature rise inflection point before the thermal runaway of the battery obtained at different temperature rise calculation intervals is analyzed, and it is considered that the temperature rise data obtained at the temperature rise interval of the 30s under the experimental conditions set in this paper can be used as an effective monitoring parameter for the thermal runaway of the battery.
Research on collaborative control and optimization of energy storage units under the high proportion of wind power infiltration
Authors: Jiang Zhiwen , Li Donghui , Lu Guanming
Published: May 2023

With the growing maturity of technology and strong support for national policies, the proportion of new energy power generation systems represented by wind power in the power network is increasing. Under the high proportion of wind power penetration in the power network, the power generation burden of thermal power generation unit is greatly reduced, and the running costs of the electricity grid system can be reduced while obtaining environmental value benefits. However, the stochastic and uncertain output of wind power poses a challenge to grid dispatch under a high proportion of wind power penetration. The energy storage power system responds quickly and can provide certain heat reserves and virtual rotational inertia for the power network, and the wind power generation system can effectively smooth the wind power output and reduce the wind power curtailment rate. This paper proposes an optimal allocation method that takes into account the operating cost of the energy storage plant, the operating cost of the thermal power generation group, the cost of wind turbine abandonment, the branch capacity constraint and the standby capacity constraint. A four-unit 14-node model is built to simulate the cooperative control of energy storage under the penetration of a high proportion of wind power in summer and winter, and verified the effectiveness of the strategy.
Power system stability margin prediction based on gradient lifting decision tree
Authors: Jiang Jiang , Huang Minglei , Ling Huaming , Wang Dapeng
Published: May 2023

The voltage is unstable due to the influence of load demand and other factors. In order to ensure the stable operation of the power system, this paper proposes a method of power system stability margin prediction based on a gradient lifting decision tree. On this basis, the stable sampling of power grid is established by using data mining method and solved. On this basis, combined with the stability simulation curve of the power grid, the operation characteristics of the power grid are analyzed, and the stability of the power grid is analyzed using the CNN model and the gradient lifting decision tree. The proposed method has better prediction accuracy and efficiency of power system stability margin, and can improve reference for ensuring the stable operation.
Cause analysis of doubly-fed wind turbine faults
Authors: Zhang Xiuqi , Li Yong , Liu Yu
Published: May 2023

Doubly-fed wind turbine is the mainstream model at present. This paper first introduces the working principle of a doubly-fed wind power generation system, counts the fault frequency and fault duration of a doubly-fed wind turbine, and makes an in-depth analysis of the fault data in the recent two years. Then it summarizes the fault components and fault types of doubly-fed wind turbines, and on this basis, analyzes the causes of the faults, which can be used as a reference for wind farms to formulate fault prevention schemes for doubly-fed wind turbines.
Operation and Maintenance Technology of Relay Protection Equipment Based on Digital Twin Technology
Authors: Tan Qian , Li Yiquan , Wang Feng , Wu Ziliang , Zhu Jia , Suo Jianglei , Liu Wei
Published: May 2023

With the scale of the power grid is becoming larger and larger. The corresponding operation and maintenance work of the distribution network is becoming increasingly intelligent, which also puts forward corresponding requirements for the reliability of safe and stable operation of the power grid. The condition assessment of relay protection applies the scientific concept of condition-based maintenance to the actual work site, which is of great significance. To judge the operation status of the equipment and provide a scientific basis for maintenance, in this paper, based on the application of digital twin technology in microgrid operation and maintenance, the method of calculating reliability probability density by function is applied to solve the problems of fuzziness, gray, and randomness of the relay protection status index. The invention can evaluate the state of the relay protection of the power system and can timely and accurately put forward the corresponding relay protection inspection and maintenance scheme, thereby improving the maintenance efficiency of the relay protection and further strengthening the power supply reliability of the power system. It can ensure the security and stability of the power system and reduce the reliable power consumption of the majority of power users.
Online Monitoring Method of Urban Cable Insulation Status Based on Grey-Markov Error Back-stepping Model
Authors: Luo Wei , Wang Jinfeng , Wei Cunliang , Li Xin , Yao Yao , Li Lingyong , Chen Fang , Li Zhihua , Luo Haibo
Published: May 2023

In order to monitor the resistance state of urban cables online and obtain the cable line insulation state accurately, an online monitoring method of urban cable insulation state based on the grey-Markov error back-stepping model is proposed, and an online monitoring system of urban cable insulation is designed. The insulation state of cables is calculated by combining the fuzzy membership function and evidence synthesis algorithm, and the grey theory is applied to predict the online monitoring data of the cable insulation state and calculate the relative error between the predicted value and the original data. Based on this relative error, a Markov error model is used to project the error between the gray predicted value and the original data at a certain time in the future, and an accurate prediction of the insulation status is obtained by back-stepping the error formula. The implementation path of online monitoring of the insulation status of urban cables is proposed using a high-performance embedded processor combined with the method proposed in this paper. The experimental findings suggest that the monitoring system can monitor the ground insulation resistance and equivalent capacitance of cable lines online, and the measurement error is within 3%.
Analysis of the Influence of Harmonics on Energy Efficiency of Typical Equipment in Distribution Network
Authors: Shen Zilun , Zheng Zhiyao , Fu Yu , Yin Zhongdong
Published: May 2023

With the continuous development of power systems, the number of non-linear loads is increasing. When harmonics flow through wires, transformers, filters, and other devices, additional harmonic losses will be generated, which will cause power loss and safety problems such as equipment overheating. However, there are few studies on loss in complex power quality environments. Considering the influence of skin effect when harmonics flow through the conductor, this paper studies the distribution of current density, explores the influence of conductor material, radius, and frequency of the current flowing through the metal on the current distribution, and proposes a calculation method of conductor harmonic resistance considering the influence of skin effect. Furthermore, the electrical energy consumption of typical devices in the distribution network is considered. Based on the theoretical calculation model, a simulation platform was established to carry out the equipment loss measurement experiment under each harmonic current, and the mutual verification between the theoretical calculation model and the experimental measurement was realized.
Research on the Construction Model of Hydrogen-Electric Integrated Energy Stations in Typical Climate Regions of China
Authors: Ren Jiayi , Li Yan , Wang Qingshan , Zhang Qun , Fan Zikai
Published: May 2023

The hydrogen-electric integrated energy station will play an important role in the new power system with renewable energy as the main body. This paper establishes an optimization model for the system configuration of a hydrogen-electricity integrated energy station, further explores the differences in optimal configuration and operation modes of different station construction modes with different basic conditions in different places, and discusses the reasons. The research shows that the economy of the grid-connected mode is the best, and the economy of the off-grid mode is the worst. The local electricity price policy, wind and solar resource endowment, and stability will significantly impact the integrated energy station. At the same time, in the regions where the wind and solar resources fluctuate greatly from month to month, hydrogen can play the role of long-term energy storage.
Grid Peak Load Shaving Method Considering EV Charging Uncertainty Based on Interval Optimization
Authors: Zhao Yuming , Wang Tao , Ma Mingyu , Zhao Wenmeng , Wang Qing , Mao Tian , Liu Zijun
Published: May 2023

With the rapid development of electric vehicles, more and more electric vehicles are entering people’s lives. However, the large-scale access of electric vehicles to the grid brings harm to the stability of grid operation, and the problem of how to guide the staggered charging of electric vehicles needs to be solved. In this paper, we consider the travel characteristics and charging characteristics of three different types of EVs: private cars, buses, and cabs, and set up a time-of-use tariff to guide EV users to charge reasonably, thus reducing the impact of charging load on the grid by cutting peaks and filling valleys. Since the charging load of EVs is an interval value, this paper introduces interval optimization theory, establishes an optimistic model and a pessimistic model, calculates the upper and lower bound of the interval respectively, and finds out the interval value of grid load after peak and valley reduction.
Development of Double Channel Transformer Voiceprint Detection System Based on MEMS Digital Silicon Microphone
Authors: Lv Xuebin , Xu Mingkai , Wang Siyuan , Wang Ning , Wang Shuying , Wang Wenyu , Jiang Mingshun , Zhang Faye
Published: May 2023

Aiming for on-line monitoring of typical mechanical faults of transformer, a two-channel MEMS digital silicon wheat voice print detection system is developed, which consists of two channel MEMS digital silicon wheat array, the host of sound acquisition system and the upper computer software with the function of displaying real-time waveform and spectrum analysis. The device can operate reliably in complex environments by adjusting the array spacing, improving the power quality, and adjusting the network protocol. Further, different test environments were built to test the resolution performance of the equipment to the center frequency of the sound source at different distances and angles of the sound source. The results show that the system can realize the resolution of the center frequency of different sound source distance and Angle, and still has a good center frequency resolution performance in the case of environmental noise. At the same time, the system has strong stability, environmental adaptability, easy installation and non-contact detection characteristics, can be used for real-time detection and diagnosis of transformer faults.
Optimization of Control Parameters for Grid-forming Energy Storage Systems Based on Sensitivity Analysis
Authors: Li Xu-dong , Li Hua , Sun Jin , Luo Lan
Published: May 2023

In recent years, the penetration rate of installed new energy generation has been increasing, the inertia of the system has been reduced, the damping has been weakened, and the anti-disturbance ability has been reduced, resulting in possible frequency oscillation of the system after disturbance, which brings potential problems to the safe and steady operation of power system. For this problem, a grid-forming control strategy of energy storage converter is proposed, based on virtual synchronization technology, to coordinate the parameter of virtual inertia and virtual damping. The simulation of a typical study case verifies the frequency control ability under different parameters and confirms the effectiveness of the parameter optimization.
Experimental study on enhancing heavy oil recovery by mobility control oil displacement agent
Authors: Zhang Yanyu , Teng Zhiyi , Ban Xiaochun , Sun Xiaofei , Luo Zhaowen , Wang Xiyan
Published: May 2023

The suitable concentration of mobility-controlled oil displacement agent was selected through laboratory experiments, and the development mechanism of mobility-controlled oil displacement agent in the water flooding process was studied. The results show that when the concentration of mobility control oil displacement agent is 0.15 %, the viscosity reduction effect is the best. Fluid injection pressure can be reduced by mobility controlled oil displacement agent. The mobility control oil displacement agent can improve the oil displacement efficiency, and the recovery rate of Tuha heavy oil is increased from 36.58 % to 65.13 %. The mobility control oil displacement agent has a strong effect of solubilization and viscosity reduction at low shear rate of the formation, and has a viscosity increase for water, so it can improve the development effect.
Power Performance Analysis of Large Capacity DC Electric Arc Furnace
Authors: Xia Zhehua
Published: May 2023

With the development of iron and steel smelting technology, the application proportion of DC electric arc furnaces will gradually increase in the future. In this paper, the Simulink model is built with reference to the 130-ton DC electric arc furnace produced by ABB ZHONG Shan Transformer Company Limited. In the model, the power performances of the large-capacity DC electric arc furnace are explored by adjusting the trigger angle, DC side arc resistance, and DC reactor values. From the result of the simulation, the power performances of the DC electric arc furnace are mainly affected by the rectifier trigger angle and DC side arc resistance.
Power Quality Problems of the Electrified Railway and Its Control Methods
Authors: Zong Ruixue
Published: May 2023

In developing the railway industry, the electrified railway plays a significant role in improving the national economy. However, the electric railway power supply system will be affected by power quality problems such as negative sequence, harmonic, and voltage fluctuation in actual operation, which will affect the operation efficiency of the electric railway power supply system. Therefore, it is meaningful to take economic and effectual governance measures against the power quality problems of electrified railways and reduce various indicators to the range allowed by a national standard. This paper summarizes and sorts out the main problems and their causes of current electrified railway power quality and several existing mainstream power quality governance schemes. It analyzes their advantages and disadvantages and finally looks forward to the directions that can be optimized and improved in the future study of electrified railway power quality problems in combination with social reality. It has a specific guiding effect on future research on electrified railway power quality.
Research on Human Behavior Feature Recognition and Intelligent Early Warning Methods in Safety Supervision Scene Video based on Yolov7
Authors: Cao Wanwan , Li Longyue , Gong Shuai , Dong Xiaoling
Published: May 2023

With the continuous improvement of infrastructure construction in China, the construction of various supporting power facilities is constantly followed up. A large number of ultra-high voltage or high-voltage power facilities, such as high-voltage transmission towers, transformers, or substations, are gradually emerging in populated areas, farmland, or fishponds where people still pass by sometimes. In such circumstances, people who do not have the qualification to contact power facilities at times approach, contact, or even climb these dangerous high-voltage transmission and distribution facilities illegally for various reasons, which not only poses a huge hidden peril or even threat to the safety of people’s lives and property but also cause a huge negative impact on the smooth operation of power infrastructure. To solve this intractable problem, this topic proposes a pedestrian detection and recognition algorithm, which can accurately distinguish between ordinary pedestrians and power grid maintenance inspectors based on YOLOv7, providing a reliable method for timely detection and early warning of pedestrians who may contact power facilities.
A Physical Topology Identification Method for Low-voltage Distribution Areas Meter Box
Authors: Wang Qiang , Mao Hao Fei , Luo Yu , Zhang Meng , Li Liang , Hong Qingbin
Published: May 2023

This paper put forward a method on the premise of not changing the hardware circuit of the HPLC communication unit of the online electrical meter. In the HPLC communication unit of the electrical meter, the electrical meter address is modulated to the electric-power line through a high-speed carrier signal by the method of on-off keying. In the intelligent molded case circuit breaker of the meter box, after the new-type instrument transformer is used to extract the signal, the optimization algorithm is adopted to extract the electrical meter address to achieve physical topology identification of the meter box, forming a physical topographic map of low-voltage distribution area at the meter box level, which has the characteristics of low cost and high identification rate. This method is particularly suitable for the situation where HPLC communication units have been used in large quantities. Based on the current meter box operating method, it can effectively achieve the physical topology identification for the low-voltage distribution area, improve the physical topology identification rate for the meter box and reduce the identification cost.
Analysis of Influence of Digitization Process on the Error Characteristics of FOCT
Authors: Li Binbin , Zhang Xiaohang , Huang Jie
Published: May 2023

All-fiber optical current transformers have a large dynamic range and fast response speed, which can meet the test requirements of complex electrical signals for a high proportion of new energy grid-connected operations. At present, the main problems are that the key components are easily affected by the complex environment of the substation, and the error stability is poor. In this paper, by analyzing the structure of all-fiber optical current transformers, the signal transmission process and closed-loop system model are established. Based on the method of numerical simulation, the influence of the digital conversion process and digital transmission process on the measurement accuracy of FOCT is analyzed, and the corresponding improvement strategy is proposed to improve the stability of the measurement error of all-fiber optical current transformers.
Research on Intelligent Frequency Regulation Capability Evaluation Technology for Coal-Fired Units Based on Autonomous Controllable PLC
Authors: Sun Yuanming , Zhang Tengyu , Zhao Xin , Sun Zhonghua , Nie Zhe
Published: May 2023

The generation frequency of grid-connected units determines the power supply reliability of the grid and primary frequency regulation, as the first guarantee to stabilize the grid frequency is affected by the category of generating units and operation mode and lacks systematic real-time optimization and monitoring means. This paper takes a 300MW sub-critical heating unit as the research object, and researches, and analyzes three aspects of signal homologation, multi-dimensional optimization, and intelligent decision-making to establish the evaluation model of the primary frequency regulation capability of the unit. The evaluation accuracy of the assessment model reaches 83%, develops the control platform based on autonomous controllable PLC, realizes intelligent dynamic control and the replacement of traditional optimization technology means, also improves the qualification rate of primary frequency regulation by about 23.2%.
Simulation of Influence of Load Model and Parameters on Frequency and Voltage Stability of Yunnan Power Grid
Authors: Deng Han , Wu Shuijun , Yue Qing , Sun Shiyun , Zhou Zichao , Xu Tao , Zhu Bo
Published: May 2023

After fully asynchronous networking with Yunnan Power Grid and China Southern Power Grid, a multi-DC sending-end grid with a relatively weak grid structure and low load level, has prominent frequency and voltage stability, which makes Yunnan Power Grid have complex security and stability problems. Therefore, beginning with the load model and its variable, in this study, the effects of four static load models and four dynamic load models are compared with regard to the frequency and voltage stability of the Yunnan power grid’s asynchronous interconnection system. It simulates and analyzes how load model parameters affect the frequency and voltage stability of the transmitting end power grid of the asynchronous interconnection system while Puqiao DC is experiencing unipolar and bipolar blocking faults.
Research on Insulator Defect Detection System Based on Edge Intelligence
Authors: Hu Xuekai , Luo Peng , Wang Wenrui , Jiang Yi , Zhou Xueqing
Published: May 2023

The paper aims at the problems of the high occupancy rate of communication resources and heavy server load caused by the image data taken during the inspection of the substation and sent to the remote server for processing. An edge intelligent inspection data processing architecture is constructed, and an insulator defect detection model based on transfer learning and YOLO v5 is proposed. The model can meet the training of a small sample network model in the case of scarcity of power equipment defect data. The proposed algorithm is compared with typical target detection algorithms, and the experimental results show that the proposed algorithm has an excellent performance in model recognition accuracy and recall rate. The trained insulator defect detection model is further deployed on the developed edge intelligent terminal for testing, and its image processing speed can meet the image processing requirements for intelligent inspection of substations. The system has good application value.
Optimization of Preparation Conditions and Purity Analysis of Ammonium Ferrous Sulfate
Authors: Liu Hongmei , Chen Ronghua , Huang Wei , Qian Hongmin
Published: May 2023

The preparation of ammonium ferrous sulfate is a typical comprehensive experiment in inorganic chemistry in universities, and is also an important part of the chemistry laboratory technology project of the National Vocational Skills Competition. The synthesis method is constantly improving. The traditional preparation experiment of ammonium ferrous sulfate was studied by reduction and green modification, and the purity of the product was analyzed by spectrophotometry. The results show that the optimal experimental conditions are as follows: the raw material of reduced iron powder with fine particle size and uniform particle size is selected, the optimum molar ratio of iron raw material to dilute sulfuric acid is 1:1.2, and the product yield and purity obtained by evaporative crystallization in water bath are higher.
Study on Process Parameters of Aluminium Alloy Oscillating Laser Double-wire Additive Manufacturing
Authors: Liu Miaohua , Long Jiangqi
Published: May 2023

To improve the deposition efficiency and forming quality of laser fuse additive manufacturing, this paper combines the advantages of oscillating laser and double-wire additive manufacturing to realize oscillating laser double-wire additive manufacturing. The feasibility of the scheme is verified through experiments, and a corresponding three-dimensional simulation model is established. Through the comparison of experiment and simulation, the forming fit is good and the accuracy of the model is verified. Finally, the forming effects under different laser oscillating frequencies and oscillating amplitudes are studied through the simulation model. The results show that the appropriate oscillating amplitude can preheat the substrate and improve wettability. The laser oscillating frequency is inversely proportional to the forming width, and a high oscillating frequency can improve the forming effect.
Study on surface fabrication and drag reduction performance of the bionic fish-scale composite structure
Authors: Wu Xueting , Wang Yonghua , Xu Jinkai , Yu Huadong
Published: May 2023

It has been researched that the surface structure of many organisms has unique resistance reduction properties and it is important to replicate the morphological features of the biological body surface on the material surface. So, a method for creating a biomimetic fish-scale surface using a laser is proposed by observing the laminar arrangement features of three common fish scales on the body surface, and a composite structure of bionic fish scale macrostructure and different microstructures of bionic fish scale were machined on on aluminium alloy surfaces. The surface morphology and elemental composition were characterized before the resistance reduction test. The results indicate that both the biomimetic fish-scale macrostructure and composite structure have an obvious effect of reduced drag, among which, maximum resistance reduction can be achieved 44.02% at a flow rate of 0.6 m/s for the bionic carp fish scale composite structure.
Nonlinear compression behavior research of molded pulp material
Authors: Li Zhihang , Tang Junjie , Mao Kuanmin , Song Hao
Published: May 2023

The molded pulp material is a popular environmentally friendly material, and many countries are strengthening its application in packaging. This paper aims at the molded pulp material’s mechanical properties. A compression test, which fits the actual work conditions is applied. And then use the standard linear solid (SLS) model to analyze the properties. The results show that the mechanical properties of molded pulp material are significantly different between the surface plane and the side plane, due to the layered distribution of the fibers. In the SLS model curve fitting results, the stiffness of the parallel spring element under edge plane load is significantly greater than that under surface plane load. This indicates long-term stable loads are more suitable for materials designed with loads parallel to the surface, the dynamic vibration energy needs to be designed on the material’s surface.
Study on the Preparation Method of Fluorescent Rock Thin Sections Made from Non-fluorescent Materials
Authors: Wang Guojun
Published: May 2023

Canadian gum, epoxy resin, and emery are used in the production of general rock thin section materials. These materials have fluorescence, so it is not possible to make fluorescent thin sections. The use of other colloids or transparency is not good, because the use of abrasive emery will also lead to the specimen having fluorescence, which cannot be selected. At present, 502 is usually used to make fluorescent sheet adhesive in China, but the colloid is soluble in water and the colloid is not impact-resistant. During sample preparation, it cannot be used for a long time by water grinding, only dry grinding or oil grinding. The samples of water grinding are susceptible to moisture and scratches, so the rock sheet cannot be preserved for a long time, which seriously affects the efficiency and quality of production. In recent years, the team has come up with a variety of materials and methods to make fluorescent rock-thin sections through repeated trials and achieved good results.
Application and Study of Epoxy Resin AB Adhesive in the Preparation of Rock Thin Section
Authors: Qiu Bihan , Han Tong , Liu Yang
Published: May 2023

Common rock thin section making and identification technology is widely used in reservoir property research of oil and gas exploration and development, and in basic analysis such as rock and mineral identification. It is also used to identify and describe tiny rock particles, fossils, fractures, and structures. The preparation of qualified rock-thin sections is critical to the accuracy of identification results. Through the research on each link affecting the production process and materials of ordinary rock slices and continuous experimental optimization and comparison, epoxy resin AB glue is used as bonding colloid material, for it is colorless, transparent, insoluble in water, impact resistant, and firmly bonded to tiny rock particles.
Analysis of Worm Deformation Behavior of GH2132 Superalloy
Authors: Wang Huizhen , Kou Ming , Yang Yong , Xiong Hua , Guo Shuo , Zhai Yuewen , Zhou Leyu , Zhang Zibo
Published: May 2023

GH2132 superalloy performances excellent properties, such as the good rupture strength and yield strength below 923K, the fine processing plasticity and the good welding properties. The warm working behavior of GH2132 superalloy at 673 K – 773K is investigated by a thermal simulator in this paper. The results show that the worm working effects at the center of specimen is the most significant compared with other positions. The deformation temperature and strain rate is the key parameters significantly affecting the warm working behavior. The increase of the temperature enhances the recovery softening effect, which reduces the stress and the work hardening effect slightly. The deformation heat is significant with the increasing strain rate, which results in the work hardening behavior does not change markedly. This study provides an important reference for the worm forming of GH2132 superalloy.