bluuebunny/crossref_metadata_2025_split huggingface dataset:
BP Neural Network for the Signal Recognition of Micro-Energy Devices
Authors: Zhang Chuting , Wang Haopeng , Zeng Huaiwang , Chen Guo , Kang Wei , Zhang Bin 
Published: January 2021

Abstract
The recognition of electrical energy generated by different micro-energy devices is a key step for effective energy management in the integrated microsystems. In this paper, we present an improved Backpropagation Neural Network (BPNN) model in conjunction with principle component analysis (PCA) and Levenberg-Marquadt (LM) algorithm. The open-circuit voltage curves containing the noise characteristics from three different types of micro-energy device including radio frequency energy harvester (RFEH), solar cell (SOR), vibration energy harvester (VEH) are used as input vector for classification model training and validation. The classifier of our model achieves a recognition accuracy of 100%, 91.8%, 83.1% for RFEH, SOR and VEH, respectively. These results indicate that our model is valid for energy recognition for these micro-energy devices and may further apply for hybrid energy management in smart systems such as wireless sensor networks (WSN).
Joint Network Smoke Recognition based on Channel Attention Mechanism
Authors: Jin Shanju , Zhao Tongzhou , An Xiaoyun 
Published: January 2021

Abstract
Aiming at the problems that traditional fire smoke recognition methods in a low recognition accuracy, a fusion network based on VGG16 is proposed, which use channel attention mechanism and contain Dense Blocks network to extract smoke features. To avoid the loss of smoke features, channel attention mechanism in backbone network is automatically to learn the importance of feature in this network. The experiment results show that the accuracy of this network is 3.0% higher than VGG16 neural network, and which is effective and feasible in smoke recognition tasks.
Research on OCT Image Diagnosis Algorithm for Diabetes
Authors: Liu Yunxiang , Chen Jian 
Published: January 2021

Abstract
Non-proliferative diabetic retinopathy (NPDR) is an early stage of diabetic retinopathy. Effective testing can stop the disease from developing. In this paper, a 7-layer convolutional neural network after migration learning based on MATLAB R2017a, was used to perform image recognition on the full-eye OCT images of normal and NPDR at various stages. The full-eye OCT images for the testing set and training set were obtained from an open source database at duke university. A total of 120 images were obtained by optical coherence tomography. There were four types of images, including 30 OCT images of normal, NPDR type 1, NPDR type 2 and NPDR type 3. We labeled 120 full-eye OCT images numerically and divided them into a training set and a testing set, 60 each. The first 15 pictures of each category are used as the training set, and the last 15 pictures are used as the testing set. Four images were randomly selected from the 60 testing set images to determine which of the four categories the extracted full-eye OCT images were. Finally, the accuracy of the convolutional neural network after transfer learning reaches the expected effect.
Application of combined gas chromatography and dielectric spectroscopy in SF6 gas insulated high voltage converter transformer bushing insulation performance
Authors: Gong Lin , Zhang Shiling 
Published: January 2021

Abstract
High voltage converter transformer bushing is widely used in the outlet part of high-end converter transformer, and its operation safety and stability directly determine the operation effect of converter transformer. The bushing of SF6 gas insulated high voltage converter transformer is a typical multi-media insulation structure. The air end of the bushing includes SF6 gas insulation medium, and the bushing tail is in contact with transformer oil. The bushing body is generally epoxy impregnated paper composite insulation structure. For the complex insulation system, the running state of converter transformer bushing should be monitored in real time. For gas phase insulation, gas chromatography is generally used to dynamically analyze the composition of SF6 gas; for epoxy impregnated paper solid insulation, dielectric spectrum technology is generally used to analyze its wide frequency domain dielectric characteristics. Therefore, the combination of gas chromatography and dielectric spectroscopy technology can effectively characterize the insulation performance of SF6 gas insulated high-voltage converter bushing. In view of this, this paper first gives the basic theory of frequency domain dielectric spectroscopy technology and gas chromatography technology, and further analyzes the current carrying and heating conditions of the central conductor of high-voltage converter bushing under overload and short-circuit conditions. The dielectric spectrum characteristics of the converter bushing core under different temperature conditions are obtained by experiment, and the Cole-Cole model is used for fitting analysis. The decomposition characteristics of SF6 insulation gas in epoxy resin composite insulator under overload and short-circuit conditions are analyzed experimentally, and the variation curve of SF6 characteristic decomposition gas with time is obtained. Combined with the above relationship between gas chromatography and dielectric spectrum, an operational evaluation strategy for the performance of SF6 gas insulated high voltage converter bushing is proposed. In this paper, for the first time, the internal insulation performance of high-voltage converter bushing is comprehensively evaluated by gas chromatography and dielectric spectrum analysis technology for the first time, which has certain theoretical and practical application value for the operation, maintenance and overhaul of converter bushing.
Study of Power System Oscillation with Wind Power Equipping Frequency Regulation
Authors: Yang Lei , Huang Wei , Wu Chen , Li Shengnan , Chen Yixuan , Kang Hongkai 
Published: January 2021

Abstract
As more and more countries and regions stipulate that wind farms need to have frequency regulation, especially in the power grid with high proportion of wind power. It’s very clear that frequency regulation can improve the frequency dynamic of power system, but the influence of frequency regulation on power system oscillation is uncertain. This paper focuses on this influence and presents a linearized model to analyze the participation of the factors. In the end, a case system named four machine two area system is applied in the simulation to verify the validity of the model.
Interoperability Analysis of Compensation Topologies for Inductive Power Transfer System
Authors: Gao Feng , Deng Junjun , Luo Zhiwei , Zhao Zhigang , He Gang , Zhao Hongzhi 
Published: January 2021

Abstract
This paper aims to discuss the interoperability of compensation topologies for the inductive power transfer system. Based on the common practice of the compensation design, three possible cases which may happen are analyzed, including LCC-S, S-LCC, and LCC-P compensation topologies. In order to evaluate the performance of these three topologies, an analysis method is proposed to investigate the electrical characteristics. The output voltage, current and power of the different topologies affected by variations of the coupling coefficient and the ratio of secondary inductance to primary inductance are analyzed to evaluate their performances. Further simulation models are built to compare the output performance of different compensation topologies.
Aerothermodynamics Response of Hypersonic Flow over a Blunt Cone under Distributed Rough Element
Authors: Tang Xiaojun , Zhang He , Yu Juan , Tang Caiyan , Li Haixia 
Published: January 2021

Abstract
A direct numerical simulation method is used to simulate the hypersonic blunt cone flow field under the condition of smooth wall and distributed rough element. The effects of smooth wall and distributed rough element on hypersonic flow field and wall are compared and analyzed, and the aerothermodynamic response characteristics of hypersonic flow field to distributed rough element are studied. The results show that the effect of the distributed rough element on the hypersonic flow field and boundary layer is significantly higher than that of the smooth wall. The friction coefficient of the wall is directly proportional to the velocity gradient of the flow direction in the boundary layer, while the velocity gradient of the flow direction is inversely proportional to the thickness of the boundary layer. The heat flux density of the wall increases at the front edge of the rough element to promote the heating, and decreases at the second half of the rough element to inhibit the heating.
B-spline Function Modeling of Electric Heating Flow Regulating Valve
Authors: Zhang Xingchao , Yang Chengzhi 
Published: January 2021

Abstract
In this paper we propose a modeling approach of electric heating flow regulating valve with B-spline function and recursive least squares method. And by means of the analysis of the structure and working principle of electric heating flow regulating valve, its correctness is validated with MATLAB simulation. The results indicate that this modeling method can realize the minimum error approximation of real working state of electric heating flow regulating valve.
Construction of digital twin ecosystem for coal-fired generating units
Authors: Yan Xiufeng 
Published: January 2021

Abstract
With the development of big data, cloud computing, Internet of things, digital twin and other technologies, the deep integration of these technologies with the energy industry is becoming the demand of production management progress, intelligent power generation has become the trend of development in energy industry.. This article gives an overview of the digital twin ecosystem of coal-fired generating units. The construction of the digital twin ecosystem is carried out from the overall architecture, and it is given a detailed introduction to DCS interface architecture, communication architecture. The digital twin ecosystem can realize real-time twins, predicting twins, simulating twins, and state evaluation, monitoring and early warning, fault diagnosis, optimization guidance, three-dimensional visualization and other functions, which can provide a predictable and visualized big data monitoring platform for real-time monitoring of the entire process of power plant operation, transparency of operation management, and timely discovery of equipment status.
Research on test method of elevator wire rope under special environment
Authors: Xue Zhaoling , Chang Xiaoqing , Feng Shuangchang , Fang Liang , Liu Yuming 
Published: January 2021

Abstract
In order to analyze the influence of different special environment on the fatigue performance of elevator wire rope, this paper refers to the existing bending fatigue test method of wire rope, and other standard to simulate different environment conditions, a test method of elevator wire rope in special environment is presented in order to study the fatigue life and scrap condition of elevator wire rope in special environment.
Construction of the training mode system of electric power skilled personnel in Tibetan areas
Authors: Liu Ruihua , Zhu Kang , Wen Hairong , Yang Li , Xi Chuan 
Published: January 2021

Abstract
This paper analyzes the characteristics of the electric power personnel training mode in Tibet, and divides the system into five main subsystems: training support subsystem, training quality assurance subsystem, teaching and training subsystem, training management subsystem and training target subsystem. It defines and preliminarily divides the five subsystems and their subordinate elements Analysis.
Research on Intelligent Monitoring and Early Warning of Electric Power Safety Based on Artificial Intelligence Technology
Authors: Liu Yu , Wang Zuowei , Pan Yingli , Zuo Yue 
Published: January 2021

Abstract
In recent years, with the continuous improvement of the national economic development level, the scale of urban construction in China is also gradually expanding. Therefore, since the monitoring system plays an important role in various industries, the establishment of an intelligent automatic management system can determine the unstable factors in the monitoring management and improve the safety performance of the monitoring system, so that the normal operation of the monitoring platform can be maintained. The establishment and function of the intelligent monitoring and early warning system are analyzed and studied in the paper, which combines traditional video monitoring equipment and data acquisition equipment into one, and launches a monitoring and early warning solution.
Parameters optimization of release force under top-excited in stuck pipe
Authors: Zheng Zhibin , Chen Jingkai , Zhang Yanting 
Published: January 2021

Abstract
Stuck drilling accident is one of the most frequent accidents in the drilling process. The operation time of release drilling is also one of the most time-consuming operations in workover process. In recent years, the technique of release, by drilling string resonance, has been introduced into the drilling field, greatly reducing working hours and improving efficiency. In this paper, the release force’s sensitivity analysis is introduced to optimize the design parameters of the device and the working parameters of the release process. First, the pipe vibration behavior under the surface vibration agitator’s action is analyzed, and the natural frequencies are obtianed analytically. Second, based on Rayleigh damping and specific boundary conditions, the damping effect equation of drilling fluid is derived under drill string vibration. Finally, the influence of structural parameters, environmental parameters, and working parameters on the clamping force is obtained. This paper casts carry through the theoretical interpretation of the release force’s sensitivity analysis by stuck release mechanism and is of significance to optimize the stuck release operations.
Study on microscale flow characteristics of electrorheological Fluids
Authors: Zhu Shisha , Lei Xianhua 
Published: January 2021

Abstract
Electrorheological fluid is a kind of intelligent material whose rheological properties change rapidly and reversibly under the action of external electric field, It has a broad prospect in practical engineering application. It is found in the research progress of electrorheological fluids. The time scale and space scale of the electrorheological effect are very small, and the flow process has some micro-scale flow characteristics. In this paper, the dynamics of dielectric particles in electrorheological fluids under static and dynamic coupling fields is numerically simulated by dissipative particle dynamics method. The influence of surface force under static field on the submicrostructure of Electrorheological fluid and the influence of electroviscosity under dynamic coupled field on the flow rate of Electrorheological fluid are also studied.
The solution of oil leakage on the joint surface of the combustion chamber casing and the rear jacket
Authors: Zeng Xianghu , Xu Ying , Zhang Yue , Xu Zhanghuan 
Published: January 2021

Abstract
In order to solve the problem of oil leakage at the flange bolted connection of the casing of combustion chamber, an implementation solution was proposed in this paper. Firstly, a simplified flange bolted connection finite element model was established in ANSYS based on the actual size of the casing. Then, the deformation of the flange joint surface under two different forms of load was analyzed. Finally, according to calculation results, the suggestion of adding gasket was proposed to improve sealing performance of casing, and the sealing effect of gaskets of different thicknesses is also studied. This article provided a reference for improving the oil leakage problem of the casing flange bolted connection.
Research on automatic correction method of spiral bevel gear error reversal based on single chip microcomputer
Authors: Xu Hang , Tian Jiule 
Published: January 2021

Abstract
Because the traditional error correction of spiral bevel gears is based on the experience of technicians to manually adjust the parameters of production equipment and machine tools, the error range of gears in production is difficult to control, which affects the pass rate of gear production. Aiming at the above problems, the automatic correction method of spiral bevel gear error reversal based on single chip microcomputer is studied. On the basis of setting up the machining parameter model of spiral bevel gear, the gear data is measured and controlled by single chip microcomputer. After processing the measured gear data, the parameter error of the machine tool is reversed. The experimental results show that the error correction method based on single chip microcomputer can reduce the error and improve the pass rate of gear.
Research on chip removal mechanism of pulse fluid negative pressure in deep hole machining
Authors: Zhang Xiao , Dong Zhen , Zhang Zhi Bing , Yao Fang Ping 
Published: January 2021

Abstract
The processes of deep hole parts is prone to chip blocking due to its large length-to-diameter-ratios. Aiming at this problem, this paper designs a pulse negative pressure chip removal device based on a negative pressure chip removal system, which realizes the supply of pulsed chip removal fluid, and establishes the pulse fluid mathematical model of the device, and analyzes the effect of pulse supply fluid on the effect of chip removal. The simulation test of its chip removal effect is carried out by the Fluent software, and the results show that the pulsed oil supply device can make the chip produce relaxing combined suction force in the chip drain channel and alleviate the occurrence of chip blocking phenomenon.
Simulation of transverse movement of tugboat without wind and waves
Authors: Wang Xiang , Zhu Yuzhu 
Published: January 2021

Abstract
The operation of berthing and unberthing large liquefied gas vessels, the operation of offshore berthing and unberthing rescue, the positioning of drilling platforms and other projects all require the assistance of Azimuth Stern Drive(ASD) tugboats. Traversing maneuver is one of the most important maneuvers of ASD tugboat. The process of traversing is unstable, complicated and easy to be interfered by the outside world. It is prone to tail flick and other dangerous situations. On the basis of previous studies, this paper uses the “Liangang 21” tugboat to carry out simulation experiments, realizes the tug’s lateral movement control, and gives the relationship between the engine speed, propeller deflection angle and lateral movement. It is of great practical significance to the actual operation of the ASD tugboat and to improving the safety of offshore operations.
Research on Lightweight Design and Finite Element Analysis of a 9 Meter Bus Body Frame
Authors: Yao Chunge , Yang Mengjie 
Published: January 2021

Abstract
The finite element model of a 10 meter bus body frame is built in Hypermesh software. The static force and modes of bus body frame under four typical working conditions are calculated by Nastran solver. The simulation of results show that the strength, stiffness, low natural frequency and vibration mode of bus body frame satisfy design requirement, and have enough potential reserve. Under the premise of ensuring the strength, stiffness and modal characteristics of bus body, the bus structure and dimensional parameters of parts are optimized to realize the lightweight design of bus body frame. The weight reduction rate of the optimized body frame is 10.57%, which verifies the feasibility of the optimized scheme.
Flight design and dynamics analysis of a new water-air UAV
Authors: Zhang Yan , Chen Xu , Zhou Jie 
Published: January 2021

Abstract
In the field of UAV research, water-air amphibious is an important direction. If water-air amphibious is realized, the UAV will no longer be restricted by the space field, and can realize various functions in the three domains of water, land and air more flexibly and freely to complete various flight and exploration missions. Therefore, this paper designs the model and flight algorithm of a new type of water-air amphibious variable wing UAV, and verifies the dynamic analysis of the relevant flight components of the UAV.
Mechanical structure design of a modularized vertebral detection and therapy instrument
Authors: Yang Yuxin , Lin Sheng 
Published: January 2021

Abstract
Compared with traditional hands-free massage therapy, vertebral detection and therapy instrument has shown good performance in improving therapeutic effect and safety. At present, foreign vertebral detection and therapy instrument have complete functions. However the cost of the instrument is expensive. Domestic vertebral detection and therapy instruments are cheaper, but the function of detecting muscle hardness is lack. In this paper, the mechanical system of a modularized vertebral detection and therapy instrument is designed. The mechanical part of the instrument is composed of three separable working modules. It has the function of detection and treatment with low cost. The modular design of the instrument solves the problem of overheating during operation, and makes it show some advantages in maintainability, expansibility and other aspects.
Research on Model Structure of SDN Based on QoS Strategy
Authors: Ren Jiyuan , Song Yang , Wang Zhe , Liu Fuyang 
Published: January 2021

Abstract
The network candidate routing data stream is restricted to reroute the data stream of same origin and same destination, which brings great limitation to the application of the algorithm. This paper proposes a multi-objective optimization oriented rerouting algorithm for congested data streams. The algorithm detects and aggregates data streams on congested links, and reroutes the detected data streams. When there is no data stream, the data streams are arranged from large to small in the congested links, and the appropriate number of data streams are selected as candidate data streams, and small streams are aggregated by source and destination addresses. In order to determine the maximum network traffic and the optimal routing of candidate data streams, multi-objective optimization is introduced to jointly optimize the network load data stream maximization and network load balancing. Finally, a non dominated genetic algorithm with elite strategy is designed to solve the multi-objective optimization problem.
Diagnosis and treatment of an abnormal vibration caused by oil whirl
Authors: Ma Lyuzhou 
Published: January 2021

Abstract
During normal operation of a 680MW unit, the vibration of No.1 bearing frequently fluctuated greatly, which caused the unit to trip. Through the test and analysis of the vibration data, it was diagnosed that the cause of vibration was oil whirl caused by insufficient bearing stability. By optimizing the installation data of bearing and adjusting shafting center, adopting special method to strengthen the stiffness of No.1 bearing, the stability of bearing bush was improved. After vibration treatment, the vibration of No.1 bearing returned to normal value.