bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Hot-Melt-Extrusion process parameters on the Feedability of Fused Deposition Modeling filaments
Authors: Liu Chuanxin , Liang Bangchao , Zhao Yangguang , Han Xiaoxiao 
Published: October 2022

Abstract
Fused deposition modelling (FDM) has shown its advantages in the field of personalized oral medicine due to its low cost, simplicity and flexible manufacturing for on- demand doses. However, most pharmaceutical-grade polymers that can be hot-melt extruded do not have the mechanical properties for high-quality FDM feedstock, and it is considered a barrier to further development of FDM pharmaceutical applications. In this paper, the impacts of Hot- Melt Extrusion (HME) process parameters on the mechanical properties of FDM filaments is explored for the brittle polymer polyvinylpyrrolidone (PVP). The results show that the feed rate greatly influences the mechanical properties of the filaments. Through the exploration of HME process parameters, the preparation method of FDM raw filaments has been further improved, and the application of brittle polymers in FDM pharmaceuticals has been broadened.
Out-of-step Splitting Control based on Network Wide Area Response Information
Authors: Zheng Chao , Chen Yijun , Li Huiling 
Published: October 2022

Abstract
Influenced by the continuous growth of renewable energy installation scale and the increasingly prominent characteristics of AC/DC hybrid structure, the disturbance behavior of large power grid is becoming more and more complex. To ensure the safety of power grid, higher requirements are put forward for the reliability, accuracy and orderliness of the out-of-step splitting control which is belonged to the third line of defense. Firstly, this paper analyzes the principle and application limitation of out-of-step splitting control of ucosφ based on local measurement information, studies the relationship and error between ucosφ and oscillation center, and the location coefficient ζ of oscillation center is defined. On this basis, the criteria of branch splitting and the control strategy of multi-branch wide area cooperative out-of-step splitting are proposed. The simulation results of AC and HVDC hybrid power grid show that the proposed strategy can adapt to the complex dynamic behavior of large power grid in which multiple generator clusters lose synchronization one after another, accurately identify the cutset corresponding to the out-of-step generator cluster, and realize the unified and orderly splitting of each branch in the cutset.
Effect of Different Current Excitation on Joule Heating of Four-Rail Electromagnetic Launcher
Authors: Zhang Pengxiang , Shu Tao , Liu Shaowei 
Published: October 2022

Abstract
Joule heat generated by current excitation during the operation of electromagnetic launcher is the main source of heat generation in electromagnetic launcher. Using the finite element method, the electromagnetic force and Joule heat generated by current excitation of different waveforms are simulated and analyzed with the help of MAXWELL software. The simulation results show that the Joule heat generated during the operation of the electromagnetic launcher can be effectively mitigated by extending the rising edge and falling edge time of the current excitation under the premise that the electromagnetic force meets the emission requirements.
Research on grid-connected photovoltaic energy storage to stabilize power fluctuations
Authors: Gao Yu , Zhou Shaodi , Kang Xingguo , Feng Xiaojing 
Published: October 2022

Abstract
Due to the instability of photovoltaic power generation, device aging and other factors, the PI parameters of the original PI controller were no longer applicable. So a grid-connected control strategy of photovoltaic energy storage with PI controller parameters optimized by an algorithm was proposed to realize the smooth suppression of photovoltaic power fluctuations. Firstly, the PI controller parameters of the energy storage control part were optimized by using the algorithm, and the optimization process was designed. Then, the second-order low-pass filter was used to distribute the photovoltaic power, and the energy control mode of the energy storage part was designed. Finally, the PI parameter effects of the optimized energy storage control part were displayed by comparing the DC bus voltage in the isolated state, and the power suppression effects under grid-connected condition were displayed by the mixed energy storage power. The rationality of the control mode of the energy storage part was verified by the SOC state diagram of the mixed energy storage. The results showed that the control strategy could effectively suppress pv power fluctuation.
Numerical simulation of Oleo-pneumatic Two-phase flow in variable shock absorber
Authors: Du Siyuan , Zhang Changming , Jia Zhiqiang , Zhou Ke 
Published: October 2022

Abstract
In the actual operation of landing gear oil-pneumatic shock absorber, there is a complex gas-liquid two-phase flow problem inside the shock absorber. In this paper, a simplified model of a metering pin variable damping orifice shock absorber is established, and the compression process of the shock absorber is simulated numerically based on CFD method combined with dynamic mesh technology to study the gas-liquid two-phase flow characteristics and the change of oil damping force. The results show that the oil flows out of the damping orifice into the nitrogen cavity in the form of turbulent jet, and the oil and gas phases are mixed and entrained, and the presence of the metering pin significantly affects the flow pattern and flow field structure of the two phases; the damping force increases continuously during the time period of 0-0.02s, and decreases slightly in the late compression period, and the different initial inflation pressures of the nitrogen cavity have little effect on the change of damping force.
Research of an intelligent fire extinguishing device for dense cable passage
Authors: Liu Sanwei , Duan Xiaoli , Huang Fuyong , Duan Jianjia , Zhang DaoYuan , Gong Liang , He Du 
Published: October 2022

Abstract
In recent years, there have been many cable (accessory) burning events in the cable channel of the company, indicating that the fire isolation measures of dense cable channel and cable intermediate joint are still not perfect, and there are still fire risks. In view of the characteristics of dense cable passage, this paper puts forward a design idea of intelligent fire extinguishing device suitable for dense cable passage. It introduces the structure of each module in detail, puts forward the function of the device and fire extinguishing principle, and expects to provide a new technology for the fire prevention and control of cable passage.
A MEMS high g acceleration sensor simulation analysis
Authors: Yang Yujun , Wang Peng , Chen Manlong , Yang Fan , Liang Yingxuan , Chen Fangfang 
Published: October 2022

Abstract
The acceleration sensor with high g value is widely used in a variety of fields, including collision impact, aerospace, and defense security and thus is a key focus in the future. The sensor with a double-ended four-beam structure is investigated in this paper via finite element simulation analysis. The measurement sensitivity of the sensor can be improved by changing the position of the cantilever beam. Furthermore, transverse interference in the X-direction and Y-direction can be eliminated in theory through the layout of piezoresistors and the Wheatstone circuit. The simulation results show that the sensor's sensitivity is 2.6μV/g while its cross-sensitivity in the X-direction and Y-direction is 0%, indicating that the sensor's performance has been substantially improved.
Online cleaning of massive data in the evaluation of the health status of wind turbines
Authors: Yuan Donghui , Han Yuan , Zhu Yuhui , Wang Yankai , Jun Rong , Qi Yongsheng , Liu Sizhe 
Published: October 2022

Abstract
The SCADA data of wind turbine contains a number of abnormal data, which seriously affects the prediction and evaluation of the health state of the turbine. Therefore, an abnormal data cleaning algorithm is proposed according to the measured wind speed - power and generator speed - power data. In this algorithm, the key SCADA parameters were selected as data cleaning objects based on the combination of the Copula function and the mutual information feature (CMI). After that, an algorithm combining the Copula function and the local outlier factor (Copula-LOF) was proposed to clean the abnormal data and filter out the abnormal data of outliers and stacking points. Finally, the actual operation data of wind turbines are used to verify the algorithm. The experimental results show that the algorithm can effectively identify all kinds of abnormal data and has a good cleaning effect on abnormal data.
Mid-long-term prediction of electrical load based on particle swarm optimization and RBF neural network
Authors: Huang Yifan , Xiong Ziwei , Zhao Yubin , Wang Wei , Xu Xingming 
Published: October 2022

Abstract
Accurate mid-long-term load forecasting is of great significance to power system planning and safe operation. Therefore, this paper proposed a mid-long-term prediction of electrical load based on PSO and RBF neural networks. Based on RBF neural network, the mid-long-term prediction model of electrical load is established, and the prediction parameters of the RBF neural network are iterated by PSO to obtain the optimal parameter value, which is the key to improving the prediction accuracy. The comparison of calculation results shows that it can improve the accuracy of mid-long-term electric load forecasting.
Five-axis toolpath planning for aero-integral blisk cavities
Authors: Shi Congcong , Zhang Xiaojian , Zhang Xu 
Published: October 2022

Abstract
Integral blisks generally made of high-temperature alloys (such as titanium alloys) are important components in aero-engines. During machining, the tool load is large and the tool wear is serious. Because trochoidal milling can maintain a small contact angle between the tool and the workpiece during the cutting process, it is widely used in the processing of complex aviation blisks. However, when the traditional U-shaped trochoidal toolpath or the maximum inscribed trochoidal toolpath is applied, there are high cutting vibration and low efficiency. Therefore, this paper proposes a new five-axis trochoidal side milling strategy, which is suitable for machining more complex three-dimensional cavities by adjusting the shape of the inscribed arc. Different from the traditional trochoidal pattern, the proposed method can generate a spatial UV parameter line-based tool path from a given complex 3D cavity and map it to the machining surface. In addition, a scheme to optimize the tool orientation of the boundary tool is proposed, so that the machine tool motion axis can run smoothly, thus the blisk can be roughened efficiently. Finally, the proposed schemes are verified by computer simulation and physical cutting experiments, and results show the validity and effectiveness.
Modeling and simulation of pure electric vehicle composite power supply
Authors: Zheng Jintang , Fu Qiye , Zhou Heng , Liu Wei 
Published: October 2022

Abstract
In order to solve the problem of high discharge current, serious heating and low service life of pure electric vehicle with single power battery system driving at high power. Design a top-level model of the composite power supply with battery and ultra-capacitor for pure electric vehicles in the simulation software ADVISOR, propose an energy management control strategy based on logic threshold control theory. Based on MATLAB/Simulink environment, set up a logic threshold limit filtering power shunt module and chose the working condition of NEDC for simulation. The results show that, compared to single battery system, a composite power system embedded in the logic threshold control strategy of filtering thought can distributes the power between the battery and the ultra-capacitor more reasonably, effectively improves the peak output power of the battery, avoiding high current charge and discharge of batteries, extends the life of the battery, and improve the vehicle's power and economy.
Simulation Research on Improved Small Signal Model of VSC Converter
Authors: Yang Jie , Li YaXin , Xiao BoYi , Ma Jun , Yi BoNian 
Published: October 2022

Abstract
Small signal model is the basis of stability analysis and control design of VSC-HVDC. In this paper, the small signal model of VSC-MTDC applies to Voltage Source Converters (VSC) in different conditions through theoretical analysis and derivation. The model of ac system can be widely used by choosing d-q synchronous reference frame flexible. Then according to voltage source converter (VSC) modulation principle, the converter model is revised through the coupling mechanism between ac and dc of converter. This article has constructed three kinds of improved small signal models applied to different conditions. By comparing of Electromagnetic transient simulation and the small-signal model simulation, the small-signal model has high accuracy.
Smart Grid Demand-side Response Model Based on Fuzzy Clustering Analysis
Authors: Li Wenwei , Wang Xiaoming , Shi Jun 
Published: October 2022

Abstract
Grid demand-side response forecasting is greatly affected by new energy generation power. Wind power generation and time are irrelevant. Wind power generation brings greater challenges to the grid, so it is necessary to study the problem of wind power generation. An improved fuzzy clustering demand-side response model based on K-means mode division is proposed, in which the number of wind speed modes of the day to be forecasted is determined according to the K-means mode division method. The historical wind speed data with high correlation coefficients are screened out by fuzzy clustering according to different wind speed modes. The experimental test analysis proves that the improved modular partition algorithm proposed in this paper can overcome the shortcomings of fuzzy clustering that can not distinguish the internal differences of data, and has higher prediction accuracy.
H
∞ Robust Frequency Control of Wind Turbine Generators and Electric Vehicles in Isolated grid
Authors: Zhu Longyang , Lin Chuanjie , Li Rong , Li Minyu , Su Xin 
Published: October 2022

Abstract
Wind turbine generators (WTGs) occupy an increasingly larger share in power system. WTGs in isolated grid lead to fluctuation in power and decrease system inertia. To reduce frequency deviation due to power fluctuation or wind speed change, model of WTGs is established based on deloading control. Considering that WTGs will have institutional wear because of frequent frequency regulation, which would short the life of WTGs, a robust frequency control strategy is proposed. WTGs and electric vehicles (EVs) are used in this control strategy. To suppress disturbances due to wind speed and uncertainty of system parameters, a H
∞ robust controller is solved using linear matrix inequality (LMI) methodology. Time-domain simulation results shows that the adopted control methodology can decrease frequency deviation during power fluctuations and wind speed changes.
Research on heat dissipation of a 1.8KW PMSM based on natural cooling and forced air cooling
Authors: Wang Yue , Tong Ningze , Guo Hailun , Chen Yong , Liu Haoran 
Published: October 2022

Abstract
With the development of high precision, high power density, miniaturization, lightweight and integration of the motor, the internal heat generation of the motor increases sharply and the effective heat dissipation space is seriously insufficient. Temperature rise caused by motor loss is the main factor to determine the motor quota. Based on the fluid-solid coupling heat transfer mechanism of Fluent, the temperature distribution characteristics of the motor under natural cooling and forced air cooling were studied in a 1.8KW permanent magnet synchronous motor, and the prototype was made for further experiments. The simulation results were close to the experimental results, and the accuracy was verified.
Simulation research on hydraulic leveling system of vehicle-mounted radar
Authors: Pan Yunping , Zhao Fangpu , Xiao Jun , Wu Ruiqi 
Published: October 2022

Abstract
In this paper, the hydraulic system of vehicle mounted radar leveling is designed. The leveling hydraulic system adopts six-point support structure and realizes high-precision leveling by means of three-pump and electromagnetic directional valve. The hydraulic system is modeled and simulated by AMESim software, and the changes of system pressure, system flow and leg displacement with time at each stage of leveling are analyzed. According to the designed hydraulic leveling system, tests are carried out under actual working conditions. By comparing the test results with the simulation results, the results show that the simulated system pressure and leveling time are 3.3% and 8.9% different from the test system pressure and leveling time respectively.
Study on surface discharge characteristics and design method of large size oil-paper insulation of electrical transformer
Authors: Zhang Shuqi , Yu Xinru , Wu Chao , Yang Lijun , Cheng Huanchao , Deng Junyu 
Published: October 2022

Abstract
When partial discharge occurs in the power transformer, the arc can further develop on the oil-paper interface between high and low potentials, and then form a path, resulting in large-area flashover. This will lead to a wide range of insulation damage, insulation failure, equipment shutdown and even large-scale economic losses. For the insulation damage caused by surface discharge of oil paper insulation, relevant scientific research institutions have carried out a large number of experimental studies. However, limited by the test conditions, the research focuses on the small-size model below 50mm, and mostly adopts the test device of uneven electric field. The research on the “large-size“ of the same scale inside the transformer is still blank. In this study, an oil-paper insulation surface discharge test platform with a large size of 50-150mm is built, the electric field conditions at the oil paper interface during the operation of transformers in engineering are simulated, and the surface discharge test of insulating paperboard is carried out by taking the same sample processing means as the engineering. Combined with the test results, a typical design optimization case of setting along surface corner ring to improve the allowable value of along surface discharge field and enhance along surface insulation margin is proposed. It lays a foundation for enriching the transformer oil-paper insulation design parameter system and improving the transformer oil paper insulation performance and operation reliability.
Electrochemical corrosion resistance of hydrophobic coatings on ZE41A magnesium alloy synthesized by hydrothermal method
Authors: Wang Dingsong , Shi Jixing , Sun Jinhao , Wang Jianxiang , Zhang Fan 
Published: October 2022

Abstract
Two kinds of hydrophobic coatings on ZE41A magnesium alloy are successfully synthesized using hydrothermal method. The surface morphologies, wettability and anti-corrosion properties of hydrophobic coatings are investigated by the method of scanning electron microscopy, X-ray diffraction and electrochemical corrosion tests. Results show that the sample treated in stearic acid ethanol solution with addition of NiSO4 exhibits a morphology possessing large numbers of fine flower-like micro/nano structures, which results in better hydrophobicity and better corrosion resistance.
Study on toughening of Fe based amorphous coatings by ultra high speed laser cladding
Authors: Zhang Jingchun , Wang Yuyue , Niu Qiang , Fan Ruijun , Wu Jianpeng 
Published: October 2022

Abstract
Fe based amorphous alloys have no defects such as grain boundaries and dislocations, with high hardness and high wear resistance. However, due to the limitation of amorphous brittleness and size effect, they have been unable to realize engineering application. Using ultra-high speed laser cladding technology to prepare Fe based amorphous powder into coating can not only give play to its excellent properties, but also avoid the limitations caused by size effect. Therefore, it has broad application prospects and is expected to become a breakthrough in the engineering application of Fe based amorphous alloy. In this paper, we make Fe52.8Cr22.4Mo18.3B2Si1.2C2.1 on 27SiMn by laser cladding, in view of the phenomenon that cracks are easy to occur in the high hardness coating, the optimization scheme of prefabricated transition layer is designed, the Fe based amorphous coating is toughened, and its wear resistance is studied. The results show that the toughening effect of Ni as the transition layer is the best, and the occurrence rate of surface micro cracks of the coating can be reduced to 35%. The microhardness of the coating is about 1200HV0.1, which is 6 times that of the substrate.
Research on Air-floating Gravity Unloading System of Large-scale Inter-mechanisms
Authors: Li Haiyue , Wang Danyu , Li Jun , Yu Haibin , Zheng Shujie , Li Guang , Tong Xuefeng , Yao Di 
Published: October 2022

Abstract
Aiming at the unloading requirements of heavy load, high stiffness and low damping of the upper mechanism during ground separation and unlocking simulation test of a certain mechanism product, a gravity unloading system based on air flotation was developed. The system can not only realize the gravity unloading of the large heavy-duty mechanism, and follow the upper mechanism to rotate at any speed, but also has small rotation resistance and stable movement. It has been verified by experiments that the air-floating gravity unloading system based on the air-floating method can realize 100% gravity unloading of products over 1 ton, and follow the upper mechanism to perform stable rotating motion, and the support deformation of the air-floating ring is better than 0.8um. The rotational resistance torque is better than 0.2Nm. To meet the unloading requirements of high stiffness and low damping of the upper mechanism, the in-depth research on the ground simulation system of the separation and unlocking between the two structures has a certain research reference value.
Effects of Process Parameters on Density of GH5188 High-temperature Alloy after Selective Laser Melting
Authors: Xu Lifeng , Chu Jiaqing , Wang Jingwen , Zhou Yan , Wang Dongsheng 
Published: October 2022

Abstract
GH5188 high-temperature alloy specimens were fabricated by selective laser melting (SLM) and influencing laws of laser power, laser velocity and laser energy density on density of specimens were researched. The results shows that along with the laser energy density increases from 73.02 J/mm3 to 88.18 J/mm3, porosity in specimens decrease and relative density increases from 98.86% to 99.75%. However, as the laser energy density increase further, the density begins to decrease continuously. The main causes that effects relatively density including: the powder is not fused at low energy density, as well as the powder splash and gasification at higher energy density. Neither inadequate nor excessive laser energy density is conducive to improvement of density of specimens. As the increase of laser velocity and laser power, density of specimens increases firstly and then decreases. The variation trend of relative density is similar with that of laser energy density and there are reasonable ranges of laser velocity and laser power. However, influencing laws of laser velocity and laser power on density of specimens are different.