bluuebunny/crossref_metadata_2025_split huggingface dataset:
Damage analysis of wind turbine blade with different stacking parameters
Authors: Zhang ZhiQiang , Qiao YinHu , Wang ShuaiShuai 
Published: June 2022

Abstract
Considering the damage and failure of wind turbine blades under gravity, centrifugal force and aerodynamic load, the influence of blade laminating parameters to the damage characteristics of wind turbine blades is studied. Different stacking schemes were designed by changing the stacking angle, stacking sequence and the ratio of ±Xn in the material. The maximum stress position of the blade was analyzed. At the same time, the failure factor of Tsai_Wu was used as the failure criterion to analyze the possibility of blade failure. The results show that the maximum stress of the blade appears at the junction of the leading edge web and the airfoil near circular airfoil and DU_35A17 airfoil; in the range of 40° ∼ 50°, as the layup angle increases, the blade Tsai_Wu failure factor shows a downward trend. On both sides of about 45°, the change trend of the Tsai_Wu failure factor is different with the increase of ±Xn thickness ratio; the Tsai_Wu failure factor of the blade material is greatly affected by the stacking angle and the thickness ratio of ±Xn.
Control strategy of controllable shunt reactors (CSR) in Zhangbei substation of Zhangbei-Xiongan UHV project
Authors: Wang Yihong , Zhang Libo , Zhang Jian , Qin Xiaohui , Yang Jingqi , Dai Qian , Qiao Zhenyu , Mao Jibing , Ma Weihua , Wang Yan 
Published: June 2022

Abstract
Based on the incremental control method of reactive power demand, this paper considers accessing the status information of low-voltage reactive power compensation devices and the reactive power exchange information of the medium-voltage side of the main transformer, so as to realize the reactive power balancing of the partition system, which is composed of the substation and half the length of substation outlets. Aiming at the actual situation of Zhangbei UHV substation interconnected with wind farms, this paper further considers the constraint of reactive power flow ride-through, so as to generate an inner-layer control strategy, which comprehensively considers the reactive power balancing of partition system and reactive power flow exchange. This inner-layer control strategy and the outer-layer control strategy of voltage boundary emergency control together constitute double-layer control strategy of controllable shunt reactors in Zhangbei UHV substation. This control strategy has passed the thematic review conference organized by the State Grid UHV Department, and has been applied to Zhangbei UHV substation.
Joint planning of distribution network and electric vehicle charging station considering extreme weather events
Authors: Liao Jie , Wang Rui , Xia Shiwei , Ren Lijun , Wang Tong 
Published: June 2022

Abstract
In order to deal with the increasing demand for electric vehicle charging and the increasingly frequent extreme weather events, this paper proposes a distribution network-electric vehicle charging station planning method considering extreme ice and snow weather conditions. Firstly, the influence mechanism of extreme ice and snow weather on distribution network line failure rate and traffic network section capacity is studied. Then the Distflow optimal power flow model is established and relaxed into a second-order cone model. Secondly, based on Wardrop user equilibrium, the distribution of mixed traffic flow between electric vehicles and non-electric vehicles is studied and the model is linearized. Finally, considering the multiple faults of the distribution network in extreme ice and snow weather, the distribution network electricity and the electric vehicle charging station are coordinated to support the key loads of the distribution network. In this paper, a planning model is established with the objective function of minimizing the annualized investment cost and the weighted operating cost under normal and extreme weather conditions, and the proposed model as a mixed-integer second-order cone problem is solved by the Yalmip toolbox. The results show that the proposed joint planning model can improve the utilization rate of equipment investment and the daily operation economy on the premise of ensuring key load supply in extreme events.
The adaptability of IEC 60909: 0-2016 to power grid with voltage levels above 400kV
Authors: Zhang Yuhong , Zhang Yantao , Han Jiahui , Wang Xueqiong , Chen Qiyu , Zhang Jian 
Published: June 2022

Abstract
The equivalent voltage source method is recommended in IEC 60909 for short-circuit current calculation, and the accuracy is verified by 400 kV and below voltage level power grids. There are 500 kV, 750 kV or 1000 kV power grids in some countries where IEC standards are applied, but there is no relevant research to verify the accuracy of the calculation method. In this paper, verification methods for IEC 60909 calculation accuracy for the three voltage level power grids are adopted. Calculation examples based on the operation and equipment parameters of the 500 kV, 750 kV and 1000 kV power grids are established. The results show that IEC 60909 short-circuit current calculation method is conservative, and the calculation accuracy meets the requirements. The research expands the application scope of this standard to all AC power grids, which is conducive to the engineering application of IEC 60909.
A Joint State Estimation Framework for Lithium-ion Batteries based on Hybrid Method
Authors: Li Qian , Miao Shuguo , Liu Shengzhong , Ma Boyang , Qi Wenyan , Jin Weijun , Cheng Ze 
Published: June 2022

Abstract
Accurate estimation of state of charge (SOC), state of health (SOH) and remaining useful life (RUL) of Lithium-ion batteries is of great importance. This paper proposes a estimation framework based on charging voltage segment and hybrid method combining with equivalent circuit model and data-driven algorithms to achieve the accurate estimation of SOC, SOH and RUL of the long life cycle of the battery. The charging voltage segment, with the merit of flexibility and available, which contains much information for battery degradation, is suitable for battery modeling and state estimation. The rising time of the optimal charging voltage segment which has the highest correlation with the present capacity is extracted as health feature (HF) to estimate the SOH with least squares support vector machine (LSSVM), and the identified resistance and capacitance parameters acquired by fitting the charging voltage segment with equivalent circuit model and estimated capacity acquired by LSSCM are used to estimate SOC with the unscented Kalman filter (UKF) algorithm in the discharge stage for this cycle; Gaussian process regression (GPR) is used to prediction the trend of HF, which are combined with established LSSVM model to estimate RUL. Experimental results show that the proposed method can estimate SOC, SOH and RUL jointly with high accuracy.
Influence of camber on aerodynamic performance of airfoil based on CFD technology
Authors: Wang ShuaiShuai , Qiao YinHu , Zhang ZhiQiang 
Published: June 2022

Abstract
In order to better understand the influence of camber on aerodynamic performance of airfoil, airfoil NACA0012, NACA2412, NACA4412 and NACA6412 were selected as research objects to conduct numerical simulation at 10m/s. According to lift coefficient, lift-drag ratio and airfoil pressure cloud diagram, the influence of camber on airfoil aerodynamic performance is obtained. The results show that the lift coefficient of airfoil increases with the increase of airfoil bending degree within a certain range of attack Angle. The lift-drag ratio of airfoil increases with the increase of its bending degree.
Research on Turn-to-Turn Insulation Test of Dry-Type Air-Core Reactor
Authors: Wang Lulu , Pei Ying , Wang Zhijun , Zhao Yishu , Song Xinxin , Zhao Jixiang , Xu Yuanyuan , Pan Zhiyuan 
Published: June 2022

Abstract
The dry-type air-core reactor insulation detection is the key component of reactive power compensation and filter device, which needs to be tested. At present, there are few researches on detection method of dry-type air-core reactor insulation. Based on the principle of pulsed voltage method and reducing test cost, the mathematical model of dry-type air-core reactor is established, the actual parameters are entered for simulation analysis. The simulation results verify the feasibility of using the pulse voltage method to detect the turn insulation between the dry-type air-core reactors, which can guide the actual dry-type air-core reactor insulation detection method.
Integrated Ni-CNT as a bifunctional catalyst for Li-O2 batteries
Authors: Cao R F , Liu J W , Liu W Q 
Published: June 2022

Abstract
Using thermal evaporation technology, Ni-CNT are grown in-situ on nickel plates as the cathode of Li-O2 batteries. This integrated electrode structure eliminates the negative impact of binders on the electrochemical performance and greatly reduces the process for preparing the lithium oxygen battery cathode. Ni-CNT exhibit excellent catalytic activity, and provide an ultrahigh discharge specific capacity of approximately 4.3 mAh cm−2 at 0.1 mA cm−2, the discharge voltage plateau is stable above 2.79 V. In addition, it exhibits a low polarization potential of only 3.34 V during charging, which is much lower than that of the commercial Ru-CNT cathode, and the cycle life of 151 cycles is much higher than that of the commercial Ru-CNT cathode even under a high specific capacity (0.3 mAh cm−2). This self-supporting structure provides abundant space for oxygen transmission and discharge products, and shows great application prospects.
Optimization of micro methanol steam reforming reactor
Authors: Zhu Ruihan , Zuo Min , He Zhenzong 
Published: June 2022

Abstract
In this paper, a micro reactor integrating hot air heating and methanol steam reforming hydrogen production (MSR) reaction is designed. Firstly, the mechanism of the reactor is studied. The Arrhenius chemical reaction rate evaluation model and simple-c algorithm are applied, the hot air is used to simulate the heat supply of engine exhaust, and the three-dimensional design simulation of the new structure reactor is carried out. The effects of the number of hot air inlet holes, parallel flow, counter flow and inlet schemes on the reactor are investigated. It is found that the conversion of methanol can reach 71.08% with the better inlet scheme of parallel flow in the two-hole condition. Then, taking the comparison of methanol conversion as the index, the correspondence between hot air and electric heating in a certain range is explored. The results of the study have implications for conducting research on the comprehensive utilization of waste heat from engines and the heat reforming for hydrogen production.
A cross-attention based image fusion Network for prediction of mild cognitive impairment
Authors: Li Jiyun , Bu Chao , Qian Chen 
Published: June 2022

Abstract
Mild cognitive impairment (MCI) is the intermediate stage in the progression of Alzheimer’s disease, where patients exhibit cognitive decline, decreasing ability to perform complex daily tasks and other symptoms that can be mistaken for normal aging, thus missing the optimal time for treatment and leading to further deterioration of the patient’s condition. Structural magnetic resonance imaging (sMRI) and positron emission tomography (PET) are commonly used to examine patients in clinical practice. Currently, the fusion of sMRI and PET based on deep learning are simply extracting features individually and then fusing the extracted features, ignoring the correlation between features of two different modalities. Therefore, this paper proposes an image fusion method based on cross-attention mechanism, which makes it possible to focus not only on the features of its own view but also on the features of the other view during feature extraction to achieve dual-attempt cross-learning. The experimental results from the Alzheimer’s Disease Neuroimaging Initiative dataset show that the images fused based on the method proposed in this paper outperform the original method in three evaluation indexes: peak signal-to-noise ratio, structural similarity and classification accuracy.
Vehicle detection in foggy weather based on an enhanced YOLO method
Authors: Li Wei 
Published: June 2022

Abstract
Vehicle detection is the key to driverless technology. For safety, driverless technology requires extremely high accuracy and real-time for vehicle detection in different situations. In this paper, we study an enhanced YOLO -based algorithm for vehicle detection in foggy weather conditions. We add a dehazing module in the YOLO model for more information restoration, which is built by the multi-scale retinex with color restoration (MSRCR). And the enhanced model is trained with the augmentation data processed MSRCR for more stable performance. We evaluate our method in the public dataset, the results show the enhanced YOLO model has better performance than conventional YOLO in vehicle detection in foggy weather.
Detection algorithm of aerial vehicle target based on improved YOLOv3
Authors: Xu Minjie , Wang Xinhua , Zhang Shuai , Wan Ru , Zhao Fukang 
Published: June 2022

Abstract
In order to solve the problems of large number, small size and low detection accuracy of vehicle targets in aerial photography, a target detection algorithm based on improved YOLOv3 is proposed in this paper. Firstly, aiming at the problem of small target information loss of road vehicles, a new detection size is added.Secondly, in order to better detect small targets, a 104x104 scale detection layer is added on the basis of the three detection layers of the traditional yolov3 network structure.The k-means + + algorithm is used to cluster the data set, and a new ground target detection candidate frame is obtained. The loss function is improved by using Focal loss function in the classification loss function and using DIoUloss function based on IoUloss improvement in the regression loss function.The improved YOLOv3 algorithm can identify the road vehicle target more accurately without the decline of speed, and reduce the miss rate. The improved algorithm is tested on Visdrone dataset, and the experimental data show that the average accuracy of the improved algorithm is 94.04%, and the average detection accuracy (mAP) is improved by 2.94%.The detection accuracy of the proposed improved YOLOv3 algorithm is better than that of YOLOv3.
UAV Aerial Photography Target Detection Algorithm Based On Improved YOLOv5
Authors: XIE Liangchen , XUE Yali , YE Jinze 
Published: June 2022

Abstract
Aiming at the characteristics of complex background and less target pixels in UAV aerial images, a UAV aerial target detection algorithm based on improved yolov5 is proposed in this paper. First, the low-level feature map with richer small target information is introduced into the feature fusion network, so a new prediction head is added. Then, the structure of the feature fusion network is improved to realize cross layer connection and assign different weights to each feature map. Finally, the loss function is optimized to further improve the detection accuracy of the model. The model is trained with VisDrone data set. The results show that the average accuracy of the improved algorithm is improved by 4.6 percentage points compared with yolov5x, and it has better detection performance for scenes with complex background and dense small targets.
Influence of inclusion defects on bending properties and failure modes of composites
Authors: Luo Ning , Xiao Shi , Wang Zhanbin , Liu Bintao 
Published: June 2022

Abstract
A comparison test was carried out between the simulated inclusion sample and the normal sample, and the test section was subjected to pure bending loading by three-point bending loading method. The influence of different inclusion positions on the bending mechanical properties of the composite was analyzed. The fracture surface of the specimen was observed macroscopically and by scanning electron microscopy, and the load transfer and failure mechanism of the specimen were studied from macroscopically and microscopically. The results show that the distance of the simulated inclusions and the position of loading surface have great influence on the bending properties of the composites. When the simulated inclusion is far from the loading surface, delamination cracking does not occur in the simulated inclusion area, and the bending property of the simulated inclusion sample is improved rather than decreased, that is, the presence of inclusion does not necessarily reduce the bending property of the composite.
Effect of Furnace Cold Annealing on Microstructure and Tensile Properties of TC18 Titanium Alloy
Authors: Zhang Yafeng , Zhang Mingyu , Pan Yizhen , Yue Xu , Tong Xiaole , Yang Mengdi 
Published: June 2022

Abstract
TC18 alloy bars were annealed at different temperatures, and then the tensile properties were tested. The effects of different furnace cooling temperatures on the microstructure and tensile properties of the alloy were analyzed by optical microscope and scanning electron microscope. The results show that after furnace cooling at different temperatures, the size, distribution and appearance of α phase in the microstructure are changed to varying degrees. With the increase of temperature, the α phase in the microstructure disappears, the elongated α phase becomes thinner, the grain boundary α phase appears, and the obvious β grain appears. The strength of the alloy increases with the increase of temperature, and the plasticity shows the opposite trend. The maximum tensile strength is 1131 MPa, the maximum yield strength is 992 MPa, the maximum elongation is 14 %, and the maximum section shrinkage is 34 %. When the temperature is in the two-phase region, the morphology is mainly dimples, and the dimple morphology is large and deep. When the heating temperature is in the single-phase region, the fracture morphology is mainly crystalline, with tearing edges and a small amount of shallow dimples distributed on the surface.
Analysis of current distribution of electrode change operation in aluminium electrolysis based on equivalent circuit computer numerical
Authors: Lv Jian , Wang Yifan 
Published: June 2022

Abstract
The development of industrial aluminium electrolytic cells towards higher series currents and a larger number of anodes, coupled with the fact that China has made more restrictions on high energy-consuming industries, has placed higher demands on the management of the aluminium electrolytic industry. In this study, a digital twin model of the electrolytic cell based on the idea of equivalent circuits was constructed using Matlab/Simulink software to simulate the electrode change operation and to study its effect on the change of current field. It is shown that the electrolysis temperature and the change of ACD caused by horizontal current have an effect on the current distribution.
Analysis of Thermal Fracture for Nonhomogeneous Materials Plate with Multiple Cracks
Authors: Sun Yiding , Zhang Zehui , Ye Ti , Zhang Yanyan 
Published: June 2022

Abstract
In this paper, the transient interaction integral method (IEIM) is established to obtain the transient thermal stress intensity factors (TSIFs) in order to study the fracture problems of nonhomogeneous materials under thermal shock loading. The transient temperature field is evaluated by using the finite difference method and the finite element method. The TSIFs of nonhomogeneous materials with multiple cracks are analysed, then the mixed-mode TSIFs of nonhomogeneous materials with different positions are discussed. The results of this study have shown that the current approach is applicable to obtain fracture parameters of nonhomogeneous materials with multiple cracks efficiently, which can be used as a significant reference for the engineering application of nonhomogeneous materials.
Experimental study on bearing capacity of a Tensairity arch
Authors: Lv Lin , Fan Zijian , Sun Haitao 
Published: June 2022

Abstract
Based on the advantages of tension-string structures and inflatable membrane structures, this paper proposes a Tensairity arch and designs and builds a model for the structure. The mechanical response of the structure under a concentrated load is studied by carrying out static tests. From three aspects of the midspan deflection deformation, the strain of upper chord member and the tension of steel cable, this paper studies the influence of the internal inflation pressure, the tension of the lower chord steel cable, and the combinations of the steel cable on the bearing capacity of the structure. The results show that increasing the inflated air pressure to a certain extent can significantly improve structural stiffness, but compared with traditional spindle-shaped Tensairity, the prestress applied during the inflation process is not conducive to enhancing the structural load-bearing capacity. Changing the stress distribution of the upper chord member by tensioning the lower chord cable is beneficial to achieve a better material performance and weaken the adverse effects caused by the inflation of the airbag. The supplementary tension of the horizontal steel cable can improve the ultimate bearing capacity of the structure, thus contributing to the safety of the structure.
Time-space Domain Elimination Method of High-Temperature Thermal Disturbance Test Error
Authors: Lou Qun , Lv Junhao , Wen Lihua , Xiao Jinyou 
Published: June 2022

Abstract
The digital image correlation (DIC) test method has been widely used in structural deformation measurement due to its non-contact and full-field. However, eliminating the effects of temperature-induced thermal disturbance is a primary challenge in high-temperature DIC measurements. In this paper, the measurement error is regarded as the superposition of zero-mean random error and non-zero mean system error, a time-space domain disturbance error elimination method is proposed to eliminate the adverse effects of thermal disturbance. Firstly, the noise images are averaged in the time domain to reduce the DIC matching error caused by zero-mean random noise. Then the noise displacement field is locally weighted quadratically smoothed in the space domain to eliminate the non-zero mean system error. The experimental results show that the proposed method can improve the high-temperature deformation measurement accuracy compared with the single-domain processing method. This paper will provide a new method for improving the measurement accuracy in DIC full-field deformation measurement under a high-temperature environment.
Displacement Analysis on Plane Stress Problems
Authors: Zhu Xuli , Ma Shanshan , Huang Haidong , Wang Xiaodong , Teng Guirong 
Published: June 2022

Abstract
The vertical z direction displacement component and its effect are not considered in the displacement analysis of the plane stress problems currently, and it may cause misunderstanding of the problems. The plane stress problems are three-dimensional problems actually because the strains are three-dimensional. The relationships among stress, strain and displacement of plane stress problems were analyzed in three-dimensional space based on the basic theory of elasticity in this paper. According to the characteristic constraints of the plane stress problems, the displacement expressions in three directions were derived. The displacement in the plane consists of the integral of the plane strain in the x-y plane and the independent function of the z-direction. Under the condition that the plane stress problem is strictly satisfied, the first stress invariant should be linearly distributed in the plane, and the displacement in the z direction is the product of the x, y related linear function and z.