bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical study on temperature distribution of the hot-plate under induction heating
Authors: Wang Jin , Chen Xing , Sun Baoshou 
Published: September 2020

Abstract
In this paper, a novel method based on electromagnetic heating theory is introduced to achieve a stable and uniform temperature distribution on the target surface of the hot-plate. The heat process of hot-plate is divided into two stages. At first, the thin layer of S45C was coated on the surface of the hot-plate by thermal spraying. Due to skin effect, coated S45C layer can be considered as heat source in terms of the law of electromagnetic heating. Secondly, the hot-plate made of pure aluminium with a high thermal conductivity can be employed to reduce the temperature difference. Finally, the target surface temperature of the hot-plate is stabilized at specific temperature by changing the holding current.
Analysis of the mechanical coupling characteristics of a monolithic tri-axis MEMS gyroscope
Authors: Wang Yue , Chen Zhiyong , Zhou Bin , Wei Qi , Zhang Rong 
Published: September 2020

Abstract
The mechanical coupling characteristics of a monolithic tri-axis micro-electromechanical gyroscope have an important effect on the performance of the gyroscope, and the coupling is directly related to the processing error. This paper introduces the structure and principle of a monolithic tri-axis micro-electromechanical gyroscope, establishes a dynamic coupling model, and studies the mechanical coupling problem caused by beam width errors. The finite element analysis tool was used to simulate the harmonic response of the gyroscope structure with beam width error. The driving-to-sensing and sensing-to-sensing coupling characteristics, the equivalent coupling angular rate of the driving mode to each sensing mode, and the cross-coupling coefficients between the sensing modes are investigated. The coupling error under unit beam width error are obtained and can be used as a reference for the structural design of the single-chip tri-axis gyroscope and the precision requirements for processing.
Development and experimental research of a test bench for sliding friction and bending fatigue
Authors: Yan Yutao , Gao Lianqi , Liu Zhenyu , Zhang Zhao 
Published: September 2020

Abstract
In order to research the fatigue damage characteristics of components under the coupling of sliding friction and bending fatigue. A test bench of the coupling of sliding friction and bending fatigue was developed based on the analysis of the principle of bending fatigue and friction experiment. The test bench mainly includes drive module, load application module, data collection and processing module. The single sliding friction test, single bending fatigue test, coupling test of sliding friction and bending fatigue can be carried out by this test bench. The three functions of test bench were carried out by 45steel experiment. The rationality and validity of the test bench were well verified by experimental measurement. The results show that the variation of life curve of coupling of sliding friction and bending fatigue is consistent with that of standard rotary bending fatigue life curve. The fatigue life of specimens is reduced on account of the effect of sliding friction. Under the low bending load, the influence of sliding friction effect on fatigue life is more significant. The fracture has typical characteristics of fatigue striations and dimples morphology.
Design of a side-feed rectangular waveguide helical array antenna with fan-beam radiation characteristics
Authors: Wu Donghua , Liu Xiankai , Luan Jin , Jiang Fujie , Tian Yi , E Yungang 
Published: September 2020

Abstract
In the millimeter wave train-ground communication system of high-speed maglev train, train-mounted antennas are required to have the characteristics of miniaturization, wide band, circular polarization, and fan-beam radiation. A side-feed rectangular waveguide helical array antenna is designed to meet these requirements in this paper. Short axial-mode helical antenna which has compact structure and circularly polarized radiation characteristics is used as the unit antenna. To realize fan-beam radiation characteristics, this array is composed of 2×15 unit antennas. All elements are fed by a rectangular waveguide which is divided into two rectangular waveguides from the side direction of the antenna. By properly designing the length of the coupling probe in the feed system, an equal excitation amplitude distribution can be realized for all unit antennas. The radiation phase of the unit antenna can be adjusted by rotating the helix arounding its axis to realize in-phase radiation of all elements. An array antenna with a center frequency of 38.0 GHz was designed through simulation. Simulation results show that the antenna has a gain of 22.1dB, an axial ratio of 2.09dB, an elevation plane beam width of 4.4°, an azimuth plane beam width of 30.1° at 38.0GHz. In the band of 37.0-39.0GHz, the reflection coefficient of this antenna is less than -15dB, the antenna gain is greater than 21.5dB and the axial ratio is less than 2.0dB which meet the design requirements of train-mounted antenna in the millimeter wave train-ground communication system.
Low-voltage distribution network topology verification method based on Revised Pearson correlation coefficient
Authors: Lou Bing , Li Cailong , Deng Jun , Zhu Linjie , Yang Cong , Chen Wujun 
Published: September 2020

Abstract
Due to the high cost and low real-time reliability of low-voltage distribution network topology checking by manual field verification, an online verification method based on revised Pearson correlation coefficient with error expectation values and KNN algorithm is proposed. Firstly, the Pearson correlation coefficient with error expectation values is used to judge the similarity between the user’s voltage curve and the transformer substation voltage curve, then the user with incorrect household relationship is found to perform re-verification. For performing re-verification, the user sample set is generated based on the data of GIS system and the Technical Guidelines for Distribution Network Planning and Design, and the K-Nearest Neighbor (KNN) algorithm is used to find out the correct station to which area the user belongs. Finally, based on the results of the manual field verification, the correctness of the algorithm verification is judged.
Analysis and implementation of SDH protocol in 10Gbps POS signal
Authors: Wei Ying , Huang Jiawei , Ling Liuyi 
Published: September 2020

Abstract
The data transmission network based on synchronous digital Hierarchy (SDH) can fundamentally solve the problems of capacity, quality, network management, security and so on in the network transmission of IP services. POS (Packet Over SDH) technology is a way to implement IP service in SDH data transmission network. An analytical solution of SDH protocol with Stratix5 FPGA as the core is studied. According to the SDH standard defined by ITU-T, the analytical circuit of SDH protocol in 10Gbps POS signal is designed on FPGA. The circuit is divided into data receiving module, line overhead module, channel spending module and status register output module, to complete data receiving, information extraction, and output of state information and net load data. The results of functional simulation and board level test show that the scheme is accurate, efficient and consistent with the standard, which can provide some reference value for the development of SDH technology.
Design and implementation of a security system based on ADSL access technology
Authors: Zhao Qiuying , He Huiwen , Chuai Yunzhi , Huang Hui , Huang Yinan 
Published: September 2020

Abstract
Taking the network switching equipment and the microcontroller as the core, a security system based on ADSL access technology is designed with the embedded method. The structure and communication mode of the security system are studied from three aspects: network switching equipment configurations, network communication module design of uplink equipment and communication module design of ADSL access equipment. The system can establish security monitoring points on existing telephone lines, which can not only meet the security protection requirements of high bandwidth, long transmission distance and information security, but can also reach the level of several kilometres. Furthermore, it can greatly reduce construction costs and operation costs of security system, and effectively realize the logistic support ability of security system.
AC sampling method based on improved half-wave Fourier algorithm
Authors: Mu Yuzhuang , Cao Hanwen , Liu Jieyu 
Published: September 2020

Abstract
This paper analyses the hardware structure of AC sampling measurement system and the basic principle of half wave Fourier algorithm in AC sampling measurement device. The hardware structure of AC sampling system is introduced. At the same time, the half-wave Fourier algorithm is improved. The improved half-wave Fourier algorithm can eliminate the error caused by the attenuation of aperiodic components. The accuracy of AC sampling is greatly enhanced. Finally, by comparing the amplitude and phase Angle errors calculated by the algorithms, the ability of the new algorithm to eliminate errors is proved.
Faults analysis of lightning stroke-caused flashover in 220 kV double-circuit transmission lines on the same tower
Authors: Zhou Luyao , Shen Jian , Liu Haojun , Wu Min , Wang Shaohua , Zhang Jichuan 
Published: September 2020

Abstract
In this paper, four-phase simultaneous lightning stroke-caused faults have been analysed, which occurred in double-circuit transmission lines on the same tower. According to the fault patrol circumstance, lightning information data, fault recording imformation, ATP-EMTP transient simulation analysis, it can be determined that the four-phase flashover faults were caused by backflashover. The specific process was: lightning stroke top or ground line of 75# tower. The lightning current was shunted by the ground wire and the tower, and was injected into the earth through the grounding device, cause high electric potential to rise on the top of 75# tower, and backflashover overvoltage formed across the insulators of phase B and phase C, leading to insulators flashover and simultaneous trip-out.
Design of power parameter monitor system based on Android mobile phone
Authors: Xie Honghu , Shao Hangjun , Chen Qiong 
Published: September 2020

Abstract
With the continuous development of power technology, real-time and accurate monitoring of power parameters in the power grid to ensure safe and stable operation of power transmission has become a hot topic of research today. The power parameter measuring instrument can realize multifunctional detection, the overall design and the combination of hardware technology and software technology, connect the mobile phone APP and hardware through WiFi transmission, and display the transmission data in real time on the smart phone terminal. Select STM32F103 as the microprocessor, adopt software synchronous sampling method, control 16-bit high-precision AD conversion chip ADS8556 for AD sampling, and then process the data by discretization method and FFT harmonic analysis algorithm, and finally send the data to The display on the Android mobile phone can realize the measurement of single-phase AC voltage and current RMS value, active power, power factor, frequency and other power parameters, and has a harmonic analysis function. The measurement data is displayed by the smartphone terminal. Tested by a test platform composed of BD-3D multi-function calibrator, the results show that its performance indicators meet the design requirements.
Study of Coal-to-Electricity Project influences on electric distribution systems in North Hebei Province in China
Authors: Zhao Min , Li Shunxin , Qin Lihan , Lyu Xin , Chen Xiangyu , Xiao Dong , Ding Jianmin , Li Xiaorong , Liu Li , Quan Luyao 
Published: September 2020

Abstract
Coal-to-Electricity Projects are being carried on in North China in order to reduce air pollution. These projects have brought many challenges to present electric distribution networks. Therefore, this paper focuses on how the practical electric distribution systems act facing a large quantity of electric heating integration and how to improve the behaviours. Field researches are conducted covering all cities in North Hebei Province. The current problems in planning, operation and investment of the power distribution networks supporting Coal-to-Electricity Projects are founded, and the reasons are analysed. The suggestions on the above three aspects are put forward accordingly. Case study on the distribution system in Xianghe County is conducted, and the effectiveness of the proposed approaches are verified. This study may give reference on Coal-to-Electricity related electric distribution work for other places and for the future, and also guide practical planning, operation and investment of power distribution systems on special issues.
Optimized design of DC shielding fittings for ±800kV UHV converter station
Authors: Zhang Wei , Yang Guohua , Wang Wenhao , Li Junhui , Fu Jianghao , Li Yongjie , Gao Ronggang 
Published: September 2020

Abstract
This paper studies the structure of the shielding device of DC device in the UHV converter station. Through simulation analysis, the electric field distribution on the surface of the shielding device is calculated to find the factors that affect the maximum field strength and the maximum electric field of the shielding device at different opening sizes and flange radius. By optimizing the structure and using a lantern-shaped shielding device, the maximum electric field strength on the surface of the shielding device of the same size can be reduced by more than 15%. The research of this project is of guiding significance for the design of shielding devices of UHV DC engineering in high altitude areas, and of great significance for promoting the progress and development of UHV DC transmission technology.
Simultaneous measurement of target distance and azimuth in four quadrant detection
Authors: Sun He , Zhang Yanmei , Li Huan 
Published: September 2020

Abstract
Realize the synchronous solution of target azimuth information and distance information in narrow pulse laser high-speed detection process to improve the time efficiency of detection system. A high-speed analog-to-digital (A/D) sampling chip, field-programmable gate array (FPGA) and related hardware circuit are used to establish a high-speed sampling and signal processing hardware system by performing related program configuration on each chip. Related algorithms such as pulse laser ranging method and azimuth resolution method based on four-quadrant detector are applied. At the same time, the denoising method based on Gauss white noise is adopted. Related simulation experiments and measured experiments are carried out. The simulation and experimental results show that the system realizes the synchronous solution of target azimuth information and distance information during the narrow pulse laser high-speed detection process, in which the distance error is not more than 1% and the azimuth error is not more than 5% and improve resource utilization rate.
On-line charging and discharging control of lithium ion battery
Authors: Wang Hong , Huang Bin , Zhang Wenhua , Zheng Mingcai , Luo Zhijun , Yin Qiang 
Published: September 2020

Abstract
In order to use lithium battery as energy storage device in DC operating power supply system, and optimize the performances of lithium ion battery such as efficiency, etc., an on-line charging and discharging control scheme for lithium ion battery in DC operating power supply is proposed. Firstly, the internal equivalent state of lithium ion battery is estimated by the output voltage and current of lithium ion battery. Secondly, the expected charging and discharging state and current value of lithium ion battery is determined by the internal equivalent state of lithium ion battery. Finally, the output voltage of AC/DC converter is adjusted according to the internal equivalent state of lithium ion battery and the expected charging and discharging state and current value. The actual charging and discharging current of lithium ion battery is forced to tend to the expected current value, so as to optimize the performances of lithium ion battery. Theoretical analysis and case study show that the scheme is feasible.
Phased-resolved partial discharge patterns of 10 kV stator coils under different experimental conditions
Authors: Kang Ailiang , Tian Muqin , Lin Lingyan , Song Jiancheng , Li Wei , Li Lu 
Published: September 2020

Abstract
The most five common types of partial discharge (PD) activities involving 10 kV motors, namely internal discharge, slot discharge, corona discharge, surface tracking and bar-to-bar discharge, were researched in this paper. PD was induced on some 10 kV coils with modern epoxy-mica insulation system through off-line experiment under different conditions. The phased-resolved partial discharge (PRPD) patterns of different types of PDs were recorded to characterize different PDs. This research can provide a reference in off-line fault diagnosis and be useful for the PD online monitoring of high voltage motors.
Reverse logistics network design considering customer convenience and low carbon emissions
Authors: Wang Bin , Hao Hao , Li Hehuang 
Published: September 2020

Abstract
Reverse logistics planning has to consider operating cost, environmental cost and customer service convenience. Muti-objective programming is applied to establish reverse logistics network planning model. The objective function is to minimize the operating costs of reverse logistics enterprises, minimize carbon dioxide emissions and maximize customer convenience. Decision variables include whether the nodes in reverse logistics network are set up or not, and the volume of logistics transportation between nodes in each stage. Constraints include meeting customer needs, flow balance among logistics nodes in each stage, capacity limitation of facilities, etc. The application of this research model can effectively improve the efficiency and sustainable competitiveness of reverse logistics enterprises.
Design and realization of metering production plan management system
Authors: Zhao Xingwang , Wang Rui , Wang Yijie , Wang Liang 
Published: September 2020

Abstract
The metrology verification center is currently developing towards intelligent, unmanned and highly reliable. For the problem of inaccurate demand reporting of electric power company, metrology verification center heavy manual planning and low efficiency, the metrology production plan management system is developed. Firstly, metrology equipment demand forecast model is constructed by integrating all kinds of metrology equipment installation history data and policy factors. It realizes the accurate prediction of the demand for metrology equipment of electric power company and supported the metrology verification center to arrange verification production and purchase new meters. Secondly, during the production planning process, intelligent auxiliary method is used. Applying demand forecast results, through analysis and quantification of many factors that affect the preparation of plans, generates arrival plans, verification plans and distribution plans that cover the metrology verification center all production business processes. It improves planning efficiency, shortens the planning cycle and achieves overall control of production rhythm.
A rapid measurement method and device for processing quality of screw conveyor in agriculture
Authors: Niu Kang , Yang Qizhi , Xing Qing , Pang Zaixi , Lv Chengxu , Zhou Liming , Xiong Shi , Li Jia 
Published: September 2020

Abstract
To improve the possessing quality of screw conveyor in agriculture, a rapid measurement method for possessing quality of the agricultural screw conveyor is proposed, and a rapid measurement device is developed. Measurement for processing quality of three main parameters is achieved, which are the shaft axial run-out, the screw blade axial run-out, and the screw blade pitch. The screw conveyor commonly used in the grain combine harvester was measured by the developed device. The test results show that: for the shaft axial run-out, the relative error is 1.47%, and the absolute error is 0.019 mm; for the screw blade axial run-out, the relative error is 2.31%, and the absolute error is 0.038 mm; for the screw blade pitch, the relative error is 1.89%, and the absolute error is 0.066 mm. It has a positive influence on the improvement of processing quality of agricultural screw conveyor.
A framework to quantify the inter-annual variation in near-surface air temperature due to change in precipitation in snow-free regions
Authors: Yin Dongqin , Roderick Michael L 
Published: September 2020

Abstract
A negative correlation between near-surface air temperature (T
a) and precipitation (P) has long been recognized over many land regions, but a predictive quantitative relationship has not yet been established. In this study, we examine inter-annual variations in T
a with P and investigate how the T
a-P relationship varies with aridity in regions without snow coverage. The wetness index is used as a measure of aridity (defined as the ratio of mean annual P to E
o, with E
o the net radiation expressed as an equivalent depth of water), with wetness index more (less) than 1.0 used to define the wet (dry) regions. Results show that variations in T
a are independent of P in wet environments, while in dry environments the variations in T
a with P increase with aridity. We use that relationship to establish a quantitative framework to a priori predict the T
a-P relation based on aridity. The results highlight the importance of inter-annual variations in P in changing T
a in dry environments, since it has similar magnitude with the decadal global warming signals over land.
Optimal feedback control in first-passage resetting
Authors: Lunz Davin 
Published: September 2020

Abstract
We study a diffusion process on a finite interval under the influence of a controllable drift where the particle resets to the left-hand side upon reaching the right-hand side. Assigning a pay-off for being nearer the right-hand side, but a penalty for reaching it, induces an inherent trade-off. We seek the drift feedback that maximises the long-term reward. By reducing the problem to a constrained variational problem we deduce that, for a wide class of problems, the optimal feedback law is remarkably straightforward: below a threshold state exert maximum drift; beyond the threshold exert minimum drift.
A thermodynamic uncertainty relation for a system with memory
Authors: Di Terlizzi Ivan , Baiesi Marco 
Published: September 2020

Abstract
We introduce an example of thermodynamic uncertainty relation (TUR) for systems modeled by a generalised Langevin dynamics with memory, determining the motion of a micro-bead driven in a complex fluid. Contrary to TURs typically discussed in the previous years, our observables and the entropy production rate are one-time variables. The bound to the signal-to-noise ratio (SNR) of such state-dependent observables can only in some cases be mapped to the entropy production rate. For example, this is true for steady states and for a subclass of Markovian systems. In fact, the presence of memory in the system complicates the thermodynamic interpretation of the uncertainty relation.