bluuebunny/crossref_metadata_2025_split huggingface dataset:
The hidden hierarchy of far-right digital guerrilla warfare
Authors: Cesarino Letícia , Nardelli Pedro H. J. 
Published: June 2021

AbstractThe polarizing tendency of politically leaned social media is usually claimed to be spontaneous, or a by-product of underlying platform algorithms. This contribution revisits both claims by articulating the digital world of social media and rules derived from capitalist accumulation in the post-Fordist age, from a transdisciplinary perspective articulating the human and exact sciences. Behind claims of individual freedom, there is a rigid pyramidal hierarchy of power heavily using military techniques developed in the late years of the cold war, namely Russia Reflexive Control and the Boyd’s decision cycle in the USA. This hierarchy is not the old-style “command-and-control” from Fordist times, but an “emergent” one, whereby individual agents respond to informational stimuli, coordinated to move as a swarm. Such a post-Fordist organizational structure resembles guerrilla warfare. In this new world, it is the far right who plays the revolutionaries by deploying avant-garde guerrilla methods, while the so-called left paradoxically appears as conservatives defending the existing structure of exploitation. Although the tactical goal is unclear, the strategic objective of far-right guerrillas is to hold on to power and benefit particular groups to accumulate more capital. We draw examples from the Brazilian far right to support our claims.
Time-like hypersurfaces of prescribed mean extrinsic curvature
Authors: Friedrich Helmut 
Published: June 2021

Abstract
The results on the initial boundary value problem for Einstein’s vacuum field equation obtained in Friedrich and Nagy Commun. Math. Phys.
201 619–655 rely on an unusual gauge. One of the defining gauge source functions represents the mean extrinsic curvature of the time-like leaves of a foliation that includes the boundary and covers a neighbourhood of it. The others steer the development of a frame field and coordinates on the leaves. In general their combined action is needed to control in the context of the reduced field equations the evolution of the leaves. In this article are derived the hyperbolic equations implicit in that gauge. It is shown that the latter are independent of the Einstein equations and well defined on arbitrary space-times. The analysis simplifies if boundary conditions with constant mean extrinsic curvature are stipulated. It simplifies further if the boundary is required to be totally geodesic.
Generalised gravitational wave burst generation with generative adversarial networks
Authors: McGinn J , Messenger C , Williams M J , Heng I S 
Published: June 2021

Abstract
We introduce the use of conditional generative adversarial networks (CGANs) for generalised gravitational wave (GW) burst generation in the time domain. Generative adversarial networks are generative machine learning models that produce new data based on the features of the training data set. We condition the network on five classes of time-series signals that are often used to characterise GW burst searches: sine-Gaussian, ringdown, white noise burst, Gaussian pulse and binary black hole merger. We show that the model can replicate the features of these standard signal classes and, in addition, produce generalised burst signals through interpolation and class mixing. We also present an example application where a convolutional neural network (CNN) classifier is trained on burst signals generated by our CGAN. We show that a CNN classifier trained only on the standard five signal classes has a poorer detection efficiency than a CNN classifier trained on a population of generalised burst signals drawn from the combined signal class space.
MICROSCOPE satellite and its drag-free and attitude control system
Authors: Robert Alain , Cipolla Valerio , Prieur Pascal , Touboul Pierre , Métris Gilles , Rodrigues Manuel , André Yves , Bergé Joel , Boulanger Damien , Chhun Ratana , Christophe Bruno , Guidotti Pierre-Yves , Hardy Emilie , Lebat Vincent , Lienart Thomas , Liorzou Françoise , Pouilloux Benjamin 
Published: June 2021

Abstract
This paper focuses on the description of the design and performance of the MICROSCOPE satellite and its drag-free and attitude control system. The satellite is derived from CNES’ Myriade platform family, albeit with significant upgrades dictated by the unprecedented MICROSCOPE’s mission requirements. The 300 kg drag-free microsatellite has completed its 2 years flight with higher-than-expected performances. Its passive thermal concept allowed for temperature variations smaller than 1 μK at the frequency of the equivalence principle test f
EP. The propulsion system provided a six-axis continuous and very low noise thrust from zero to some hundreds of micronewtons. Finally, the performance of its DFACS (aimed at compensating the disturbing forces and torques applied to the satellite) is the finest ever achieved in low Earth orbit, with residual accelerations along the three axes lower than 10−12 m s−2 at f
EP over 8 days.
2D spatially resolved O atom density profiles in an atmospheric pressure plasma jet: from the active plasma volume to the effluent
Authors: Steuer David , Korolov Ihor , Chur Sascha , Schulze Julian , Schulz-von der Gathen Volker , Golda Judith , Böke Marc 
Published: June 2021

Abstract
Two-dimensional spatially resolved absolute atomic oxygen densities are measured within an atmospheric pressure micro plasma jet and in its effluent. The plasma is operated in helium with an admixture of 0.5% of oxygen at 13.56 MHz and with a power of 1 W. Absolute atomic oxygen densities are obtained using two photon absorption laser induced fluorescence spectroscopy. The results are interpreted based on measurements of the electron dynamics by phase resolved optical emission spectroscopy in combination with a simple model that balances the production of atomic oxygen with its losses due to chemical reactions and diffusion. Within the discharge, the atomic oxygen density builds up with a rise time of 600 µs along the gas flow and reaches a plateau of 8 × 1015 cm−3. In the effluent, the density decays exponentially with a decay time of 180 µs (corresponding to a decay length of 3 mm at a gas flow of 1.0 slm). It is found that both, the species formation behavior and the maximum distance between the jet nozzle and substrates for possible oxygen treatments of surfaces can be controlled by adjusting the gas flow.
Universal route for the emergence of exceptional points in PT-symmetric metamaterials with unfolding spectral symmetries
Authors: Fang Yanghao , Kottos Tsampikos , Thevamaran Ramathasan 
Published: June 2021

Abstract
We introduce a class of parity-time symmetric elastodynamic metamaterials (Ed-MetaMater) whose Hermitian counterpart exhibits unfolding (fractal) spectral symmetries. Our study reveals a scale-free formation of exceptional points in those Ed-MetaMaters whose density is dictated by the fractal dimension of their Hermitian spectra. We demonstrate this scale-free EP-formation in a quasi-periodic Aubry-Harper Ed-MetaMater, a geometric H-tree-fractal Ed-MetaMater, and an aperiodic Fibonacci Ed-MetaMater—each having a specific fractal spectrum—using finite element models and establish a universal route for EP-formation via a coupled mode theory model with controllable fractal spectrum. This universality may enable the rational design of novel Ed-MetaMater for hypersensitive sensing and elastic wave control.
Revisiting 129Xe electric dipole moment measurements applying a new global phase fitting approach
Authors: Liu Tianhao , Rolfs Katharina , Fan Isaac , Haude Sophia , Kilian Wolfgang , Li Liyi , Schnabel Allard , Voigt Jens , Trahms Lutz 
Published: June 2021

Abstract
By measuring the spin precession frequencies of polarized 129Xe and 3He, a new upper limit on the 129Xe atomic electric dipole moment (EDM)

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was reported in Sachdev et al (2019 Phys. Rev. Lett.
123, 143003). Here, we propose a new evaluation method based on global phase fitting (GPF) for analyzing the continuous phase development of the 3He–129Xe comagnetometer signal. The Cramer–Rao lower bound on the 129Xe EDM for the GPF method is theoretically derived and shows the potential benefit of our new approach. The robustness of the GPF method is verified with Monte-Carlo studies. By optimizing the analysis parameters and adding data that could not be analyzed with the former method, we obtain a result of

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in an unblinded analysis. For the systematic uncertainty analyses, we adopted all methods from the aforementioned PRL publication except the comagnetometer phase drift, which can be omitted using the GPF method. The updated null result can be interpreted as a new upper limit of

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at the 95% C.L.
Can scale-dependent cosmology alleviate the H0 tension?
Authors: Alvarez Pedro D. , Koch Benjamin , Laporte Cristobal , Rincón Ángel 
Published: June 2021

Abstract
Scale-dependence is a common feature to all effective models of quantum gravity. In this paper, a cosmological model based on the scale-dependent scenario of gravity is presented. It is argued that such models, where the scale-dependence appears as a correction to the classical ΛCDM evolution, have the potential of addressing the tensions between early and late time measurements of H0. After defining criteria to parametrize this tension, we perform a numerical scan over the parameter space of the scale-dependent model, subject to these criteria. In this analysis, it is found that, indeed, the tension can be released.
Intelligent Drying Rack System based on Internet of Things
Authors: Xing Xiao , Zhang Chong , Gu Jieming , Zhang Yixin , Lv Xinrun , Zhuo Zihan 
Published: June 2021

Abstract
With the innovation and development of science and technology, the convenience and intelligence of home life has become a trend. This intelligent drying rack system based on the Internet of Things uses the OneNET cloud platform as the information port, and selects the STM32F103C8T6 single-chip microcomputer as the main control chip to read, judge and output the execution signal from the signal collected by the sensor. The smart drying rack can be operated manually and remotely through the touch screen, related hardware circuits and mobile phone APP, which can control the extension and recycling of the clothes drying rod, and the automatic drying and storage of clothes. It is convenient to use and improves the intelligent level of the drying rack. The problem that the drying rack cannot dry the wet clothes and needs to be stored manually is solved.
Simulation Research on the Post-arc Dielectric Recovery Characteristics of Multi-break Vacuum Circuit Breakers
Authors: Ai Shaogui , Fan Yiping , Ni Hui , Huang Yongning , Gong Yujie , Wang Zhenxing 
Published: June 2021

Abstract
The dielectric recovery characteristics are very important for the successful interruption of the vacuum circuit breaker. In order to explore the influence of the post-arc dielectric recovery characteristics of the multi-break vacuum circuit breaker on its breaking, this article establishes a simulation model of the multi-break vacuum circuit breaker and a 750kV short line fault simulation circuit in MATLAB. By adjusting the dielectric recovery characteristics of different breaks, the critical dielectric recovery rate (The minimum dielectric recovery rate of the break when the circuit breaker does not break down) under different conditions is finally obtained. In addition, the influence of the equalizing capacitor on the critical recovery rate is also explored. It is found that the smaller the grading capacitance, the greater the voltage of the break, and the greater the critical dielectric recovery rate.
Convenient Power Supply Scheme Design for Remote Areas
Authors: Gong P , Hu P T , Zhu Y Q , Xia R H 
Published: June 2021

Abstract
At present, there are still a large number of people worldwide without electricity in remote villages. Electricity supply is one of the important conditions restricting the development of remote areas. In order to solve the power supply problem in these remote areas, this paper proposes a convenient power supply scheme. It adopts modular, flexibly configurable independent power supply based on renewable energy power generation technology, and is equipped with a backup power generation device based on human or animal power to ensure a certain degree of power supply reliability. Use easy-to-implement power supply equipment configuration and installation methods to achieve convenient layout of the power supply system. The above power supply scheme was evaluated in terms of technical feasibility, economy and social significance. Introduction
Design of real time system to measure the voltage signal in high voltage power supply
Authors: Li Zelin , Pan Gaofeng 
Published: June 2021

Abstract
The output voltage signals should be measured in real-time, and it is sent to a control system for feedback control and protection in the high-voltage power supply with high-voltage, strong magnetic field, or strong power condition. In order to obtain a stable output voltage and a rapid response of the protection in the high-voltage power supply system, the measurement of the voltage signal needs to meet three requirements: response in real-time, accurate, and high isolation. Using the voltage-to-frequency (V/F) converter AD650 to transmit the analog signals as frequency form through the digital optical fiber is the best mode to measuring the signals with high precision, real-time, long-distance, and high isolation. The composition and principle of the real-time voltage measuring device are described in this paper. The design of the hardware and the parameters are analyzed and discussed in detail. The experimental results show that the circuit structure based on the AD650 chip is simple. The optical fiber transmission can achieve high isolation and high accuracy (better than 0.1%). The low response time (under 30us) can meet the requirements of the real-time voltage signal measurement system. The signal will not be affected by the high electromagnetic field in the transmission process. The measurement system has been applied in the high voltage power supply with excellent linearity and high isolation.
Impact of Phase Locked Loop on Commutation Failure in LCC-HVDC
Authors: Tang Peiyuan , Yuan Xiaoming , Lu Jun 
Published: June 2021

Abstract
Besides the DC faults, AC faults and faults in converter, the dynamic process of control system has its influence on commutation failure. As an important element in LCC-HVDC control system, PLL provides the reference phase of receiving end power system for valve control system. When there is a difference between the real phase of receiving end power system and the output from PLL, control system cannot adjust extinction angle accurately. In this paper, the function of PLL in HVDC control system and the characteristic of PLL’s tracking process are analysed. Then the influence of the phase error caused by PLL’s tracking process on the extinction angle is discussed. At last, a detailed LCC-HVDC model is used to prove the impact of PLL’s dynamic process on commutation failure and test the influence of PLL with different parameters on commutation failure.
Current Measurement for Curved Conductor based on 3-D Coreless TMR Sensor Array
Authors: Guo Chunxian , Chen Lin , Zhang Huaiqing 
Published: June 2021

Abstract
Magnetic sensor arrays have been widely used in current measurement due to their advantages of small size, low power consumption, high sensitivity, wide bandwidth, and large dynamic range. However, researches in recent years all assume that the conductor is long-straight, while in actual engineering the conductor is usually curved. And the error introduced by curvature has not been searched until now. In this paper, a correction method based on circular 3D magnetic sensors array is proposed. The simulation results show theoretically that the method can greatly reduce the error. 3-D tunnel magnetoresistance (TMR) chip is selected as the magnetic sensors of the circular array in laboratory experiment, and the experiment errors can be reduced to around 1%. The simulation and experiment results verify that the correction method can improve the accuracy of the current measurement.
An arc contacts life assessment method based on dynamic resistance measurement and bp neural network
Authors: Chen Bangfa , Chen Xianxi , Diao Muxin , Xiao Guangyu , Yan Jing , Wang Zhenxing 
Published: June 2021

Abstract
Arc contacts ablation of high voltage SF6 circuit breaker will cause potential problems for safe operation of the grid. In view of the difficulty of predicting arc contacts life by existing methods, an arc contacts life assessment method based on dynamic contact resistance and BP neural network is proposed. The dynamic contact resistance-travel curve is obtained from the high-current ablation experiments, from which the data characterizing the arc contacts state is extracted as samples to train the neural model. The model is optimized by k-fold cross-validation method, which is finally validated by experimental results. The results show that the arc contacts life prediction value agrees well with the experimental value, which means that the BP neural network can effectively predict the arc contacts life and provide a basis for decision making for arc contacts overhaul and replacement.
Simulation and analysis on peak load regulation of office and living parks
Authors: Jin Feng , Kang Li , Liang Jishen 
Published: June 2021

Abstract
With the rapid economic development and the rapid increase in human living demand, the load power is constantly increasing, and the range of change is also increasing substantially. The peak-valley difference of daily load is increasing, which brings challenges to the peak-shaving of the power grid. The microgrid can not only supply sufficient power to the load, but also track part load changes, and has good economic benefits. Due to both of the variety of load types and the capacities of loads, the problem of peak shaving in the microgrid has also emerged. Using “source load” peak shaving to relieve peak shaving pressure is a good approach. This paper takes the minimum load fluctuation rate as the objective function, and uses the improved particle swarm optimization algorithm to simulate the peak load regulation in office and living parks. The results show that the “source load” peak shaving can make the load curve smoother. It is effective for “source load” to participate in peak shaving.
The Impact of Voltage Stability Constraint L-Index on Power System Optimization Base on Interior Point Algorithm by Considering the Integration of Renewable Energy
Authors: Nou Pheakna , Zhang Yiyi , Yang Yude 
Published: June 2021

Abstract
Renewable energy (RE) generation including wind and solar farms has experienced significant growth due to the challenge of climate and energy crisis. High penetration of RE affects system stability and generation cost optimization. In this paper, voltage stability L-index is proposed as the constraint of the primal-dual interior point method for optimal power flow by considering the integration of wind and photovoltaic cell power on system. L-index is used in this study to indicate the voltage security while renewable energy is prefixed into power system to build a new (REL-OPF) formulation that can consider the voltage stability margin and generation cost of the power grid. Weibull and Beta probability density functions are applied to determine the outputs of wind and photovoltaic power generation respectively. This model has the advantage that there is no need to calculate the critical point and could obtain the demanded voltage security level by adjusting the upper limits of indicator L constraints. The optimal solution can concurrently satisfy both the voltage security and the economical demand for power systems. The overall problem is simulated under coding written in MATLAB environment. The results obtained from regulating the upper limit of voltage stability constraint on IEEE30-bus has shown that the attention of RE generations into the system leads the fuel cost objective to decrease randomly as well as enlarge the distance of stability to a critical point with faster convergence.
Harmonic analysis of AC drive double PWM back to back network side
Authors: Dong Yijun , Yang Kai , Wang Jizhong 
Published: June 2021

Abstract
Aiming at the problem of harmonic pollution in the control system of large-scale steel rolling equipment in metallurgical plant, the mechanism of harmonic generation in AC-AC frequency conversion and AC-DC-AC variable-frequency speed regulation system is analyzed, and a double PWM back-to-back AC speed regulation system is proposed. This system can not only realize the regeneration energy of frequency converter, but also reduce the harmonic wave, and greatly improve the power factor of the system. Finally, through MATLAB simulation, the harmonic of AC-AC frequency conversion and AC-DC-AC variable-frequency speed regulation system is analyzed, and compared with PWM back-to-back AC speed regulation system, the superiority, effectiveness and feasibility of PWM back-to-back AC speed regulation system design for large-scale AC drive device control are proved.
Offline Measurement of Induction Motor Rotor Time Constant Based on Least Squares Algorithm
Authors: Cai Meidong , Zhao Yun , Nie Yaping , Liao Zhengbin , Wang Zefei 
Published: June 2021

Abstract
In order to solve the problems of disturbance and error accumulation in the traditional off-line strategy of rotor time constant, this paper optimizes the off-line measurement method of rotor time constant of induction motor. The off-line measurement method of rotor time constant based on recursive least squares (RLS) algorithm is analyzed in detail. Through the static characteristics of induction motor, the mathematical model of induction motor is simplified, and then the linear model of RLS algorithm is derived. The simulation results show that the rotor time constant measured by the least square method is more stable than that measured by the conventional method, which proves the practicability of the off-line measurement method. Finally, the error analysis of the main factors affecting the off-line measurement results of the rotor time constant based on the least square algorithm is given.
Loss Study of Dual Stator Low Speed High Torque Synchronous Motor with Hybrid Rotor
Authors: Fu Zongkun , Zhang Fengge , Zhang Zhaoyu , Jin Shi 
Published: June 2021

Abstract
Low speed and high torque machines are widely used in industrial production, oilfield mining, wind power generation, etc. Low speed high torque motors have large internal space, in order to make full use of internal space this paper proposes a dual stator low speed high torque synchronous motor. The rotor adopts a surface-mounted permanent magnet rotor structure on one side, and a spliced reluctance rotor structure on the other side. A magnetic ring is added in the middle to make permanent magnet and magnetic resistance independent of each other. The motor has a special structure, and the loss distribution is different from that of a normal motor. The loss will affect the performance of the motor. This paper establishes the iron loss model considering the effects of alternating magnetic field, rotating magnetic field, and harmonics. Considering the influence of temperature on copper loss. Then establish a mathematical model of core loss and copper loss. Then studying the motor iron loss and copper loss distribution characteristics. Finally, the results are compared with the finite element method (FEM) to verify the effectiveness of the loss calculation in the paper.