bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bubble wall velocities in local equilibrium
Authors: Ai Wen-Yuan , Garbrecht Björn , Tamarit Carlos 
Published: March 2022

Abstract
It is commonly expected that a friction force on the bubble
wall in a first-order phase transition can only arise from a
departure from thermal equilibrium in the plasma. Recently however,
it was argued that an effective friction, scaling as γ2

w

(with γ
w
being the Lorentz factor for the bubble wall
velocity), persists in local equilibrium. This was derived assuming
constant plasma temperature and velocity throughout the wall. On the
other hand, it is known that, at the leading order in derivatives,
the plasma in local equilibrium only contributes a correction to the
zero-temperature potential in the equation of motion of the
background scalar field. For a constant plasma temperature, the
equation of motion is then completely analogous to the vacuum case,
the only change being a modified potential, and thus no friction
should appear. We resolve these apparent contradictions in the
calculations and their interpretation and show that the recently
proposed effective friction in local equilibrium originates from
inhomogeneous temperature distributions, such that the
γ2

w
-scaling of the effective force is violated. Further, we
propose a new matching condition for the hydrodynamic quantities in
the plasma valid in local equilibrium and tied to local entropy
conservation. With this added constraint, bubble velocities in local
equilibrium can be determined once the parameters in the equation of
state are fixed, where we use the bag equation in order to
illustrate this point. We find that there is a critical value of the
transition strength αcrit such that bubble walls run
away for α>αcrit.
The nuclear symmetry energy from relativistic Brueckner-Hartree-Fock model *
Authors: Wang Chencan , Hu Jinniu , Zhang Ying , Shen Hong 
Published: March 2022

Abstract
The microscopic mechanisms of the symmetry energy in nuclear matter are investigated in the framework of the relativistic Brueckner-Hartree-Fock (RBHF) model with a high-precision realistic nuclear potential, pvCDBonn A. The kinetic energy and potential contributions to symmetry energy are decomposed. They are explicitly expressed by the nucleon self-energies, which are obtained through projecting the G-matrices from the RBHF model into the terms of Lorentz covariants. The nuclear medium effects on the nucleon self-energy and nucleon-nucleon interaction in symmetry energy are discussed by comparing the results from the RBHF model and those from Hartree-Fock and relativistic Hartree-Fock models. It is found that the nucleon self-energy including the nuclear medium effect on the single-nucleon wave function provides a largely positive contribution to the symmetry energy, while the nuclear medium effect on the nucleon-nucleon interaction, i.e., the effective G-matrices provides a negative contribution. The tensor force plays an essential role in the symmetry energy around the density. The scalar and vector covariant amplitudes of nucleon-nucleon interaction dominate the potential component of the symmetry energy. Furthermore, the isoscalar and isovector terms in the optical potential are extracted from the RBHF model. The isoscalar part is consistent with the results from the analysis of global optical potential, while the isovector one has obvious differences at higher incident energy due to the relativistic effect.
A Common Envelope Jets Supernova (CEJSN) Impostor Scenario for Fast Blue Optical Transients
Authors: Soker Noam 
Published: March 2022

Abstract
I propose a new scenario, the polar common envelope jets supernova (CEJSN) impostor scenario, to account for AT2018cow-like fast blue optical transients (FBOTs). The polar CEJSN impostor scenario evolves through four main phases. (1) A red supergiant (RSG) star expands to tidally interact with a neutron star (NS) companion (or a black hole). The interaction increases the RSG mass loss rate to form a circumstellar matter (CSM) halo to r ≃ 0.1 pc. (2) Shortly before the onset of a common envelope evolution (CEE) and about a year before explosion the NS accretes mass from the RSG envelope and launches jets that inflate two opposite lobes in the CSM within ≈100 au. (3) The NS-RSG system enters a CEE phase during which the system ejects most of the envelope mass in a dense equatorial outflow. (4) At the termination of the CEE the leftover envelope forms a circumbinary disk around the NS-core system. The NS accretes mass from the circumbinary disk and launches energetic jets that, when colliding with the fronts of the CSM lobes, power an FBOT event. The low mass of the jets-lobes interaction zones and their large distance, of about 100 au, from the center account for the fast transient. In the future the core collapses to form a second NS. In the far future the two NSs might merge. I suggest that FBOTs and similar fast transients are CEJSN impostors which compose a large fraction of the progenitors of NS-NS merger binaries.
Joint Control Strategy of Microgrid Inverter Based on Optimal Control and Residual Dynamic Compensation
Authors: Hu Changbin , Liu Chao , Luo Shanna , Yan Heming 
Published: March 2022

Abstract
With the continuous development of microgrid, the inverter under traditional PID control is difficult to meet the power quality requirements of microgrid. In order to improve the anti-interference ability and transient response speed of the output voltage of Isolated AC microgrid inverter, a dynamic compensation control structure combining linear quadratic optimal control and disturbance residual generator is proposed in this paper. Firstly, the quadratic optimal controller is established based on the inverter model. Secondly, the residual generator is established to observe the residual value of the disturbed system. Then, the dynamic compensation controller is designed according to the superposition principle, and a control signal opposite to the influence caused by the disturbance is output at the output of the controller. The disturbance signals can cancel each other without knowing the specific disturbance form. Finally, the experiments of load switching, three-phase imbalance and nonlinear load are designed on MATLAB/Simulink simulation software to verify the effectiveness of the control strategy proposed in this paper.
Dynamic Compensation Control Strategy for DC Converter Based on Linear Optimal Quadratic
Authors: Hu Changbin , Wang Huiru , Luo Shanna , Huang Yufei 
Published: March 2022

Abstract
Aiming at the problem of DC bus voltage fluctuation, a DC-DC converter control method combining LQR (Linear Optimal Quadratic) and dynamic compensation control is proposed. Firstly, the state space model of DC-DC converter is established. Secondly, according to the following characteristics of LQR controller, the error of the controlled output is introduced into the integral control as an extended state to eliminate the output tracking error. Then, in order to suppress the voltage fluctuation caused by load switching of DC-DC converter during power grid operation, a dynamic compensation structure based on disturbance observer is designed through robust coprime decomposition and Euler parameterization theory. The structure compensates directly at the input of the current loop, and the compensation controller Q(s) is calculated by model matching. Finally, the simulation is carried out by Matlab / Simulink. The results show that without changing the structural parameters of the original system, the new control architecture can effectively suppress the DC bus voltage fluctuation caused by load theft and power fluctuation, and enhance the anti-interference performance and dynamic performance of the system.
Energy Saving Control of Integrated Energy Multi-Energy Complementary Coupling Space Heating System Based on Fuzzy Theory
Authors: Hu Changbin , Zhao Xinyu , Luo Shanna , Lu Xiaojun 
Published: March 2022

Abstract
Because the traditional solar-ground source heat pump heating system uses temperature difference controllers to control most, it causes the problem of large energy consumption of the equipment. In order to improve such problems, the complexity of the space heating control system is considered comprehensively, and the fuzzy strategy is used to improve the previous control system. TRNSYS was used to build a heating system simulation model, MATLAB was used to build a solar heating system fuzzy controller model, and the two models were coupled to jointly simulate the internal temperature change and energy consumption of the space under the same environmental conditions and different controllers. Experiments show that under the design conditions, the solar collector is greatly affected by the light, the temperature of the hot water storage tank is controlled between 58°C and 65°C. Using the traditional temperature difference controller, the system COP (Coefficient Of Performance) is low and the energy consumption is large, and the economic benefits are not high; the use of the fuzzy controller can increase the system COP by 6.1%, reduce the energy consumption by 22.85%, and save 8.71 yuan in the daily economic benefits of the system.
Research on BIM model lightweighting methods and IoT technology application in the context of WebGL
Authors: Yuan Yuhe , Yang Jing , Shao Ruping , Mao Jiahuan , Zhang Chengwei 
Published: March 2022

Abstract
In view of the fact that most of the existing building information modeling (BIM) platforms are based on the Client/Server (C/S) mode of client-side applications, which brings about problems such as weak data interoperability, poor model semantic integrity and bad user-friendliness, this paper proposed an IFC-JSON and IFC-glTF model file format conversion process based on WebGL and an improved Draco algorithm that can further lighten glTF files. The experimental results showed that this option can effectively reduce data redundancy, then combined IoT (Internet of Things) as well as sensor technology in project practice to collect and transmit building-related O&M data, and finally visualised the equipment status of the building on the Web based on WebGL technology, providing a new application way for the combination of BIM technology and IOT technology in the browser/server mode.
Computing offloading method with low power consumption constraint for smart grid
Authors: Wu Yuebin , Lu Pengcheng , Bu Xiande , Liu Shidong , Zhong Cheng , Liu Chuan 
Published: March 2022

Abstract
With the development of the Power Internet of Things, power transmission and transformation business have a wide range of operation, large regional differences, a wide variety of equipment and other problems, making the access and deployment of mass sensors with low power consumption crucial. In order to realize the cloud-side collaborative computing of the Internet of Things, it is necessary to build a low-power information acquisition and transmission network, and realize the low-power deployment of the low-power sensor network and equipment. The embedded node device can be used as the basis of low-power transmission network to realize low-power transmission of cloud-side collaborative computing information, combined with the existing low-power transmission and transformation equipment.
Intelligent computing and analysis of breakdown voltage of rod-rod long air gap
Authors: Yao Xiuyuan , Yang Bingxue , Geng Jianghai , Su Yu , Yu Hua , Yang Guohua , Wang Xinwei 
Published: March 2022

Abstract
The discharge characteristics of air gap is one of the important factors to determine the insulation level which is crucial for electrical engineering construction. In order to calculate the 50% breakdown voltage of rod-rod air gap under different meteorological conditions and different gap distances, we take the positive standard switching impulse test data of rod-rod air gap under different meteorological conditions as samples. Based on training set, a breakdown voltage prediction model of rod-rod air gap under different meteorological conditions was established by cuckoo search optimized weighted support vector regression (CS-ω-SVR). The results show that the average absolute percentage error of the test set is 3.6%, which verifies the validity of this computing method. The method can provide reference for the computation of air gap breakdown voltage under different altitudes and extreme meteorological conditions.
Reinforcement Learning Optimized Intelligent Electricity Dispatching System
Authors: Xiao Xinhang 
Published: March 2022

Abstract
With the rapid development of artificial intelligence, new changes are coming to all walks of life including traditional manufacturing industry, bio-pharmaceutical industry, electric-power industry, etc.. For electric-power industry, many machine learning algorithms have been used to achieve intelligent dispatch of electricity, intelligent electricity equipment fault diagnosis and more optimized customer management, among which the automation of power network is one of the most important issue ensuring safe operation of electricity grid. In the recent years, intelligent dispatch method based on big data analysis has been used in intellectual scheduling of electricity and has got significant promotion. However, the intelligent dispatch on big data analysis needs tremendous history data that is sometime not that easy to get. Moreover, once a small probability event happens, the big data based intelligent dispatch method may lose efficacy, thus in this paper we proposed a new intelligent dispatch model based on the reinforcement learning that is more robust, safer and with higher efficiency. Finally, according to the empirical study result, our model outperforms the traditional methods, where the average economic benefit in the test area increases more than 25%, fluctuation of distribution is more stable than before and the carbon emission decreases about 30%.
Numerical study of RC slabs under two-point contact explosion load
Authors: Yuan Xinjing , Song Jian 
Published: March 2022

Abstract
As an important bearing component of bridge, bridge deck is the key to bridge passage. In this paper, a solid model of reinforced concrete slab is established in LS-DYNA software, and the parameters are designed as the amount of explosive and the distance between explosives. The numerical simulation of two-point explosion test is carried out, and the damage mechanism and dynamic response of reinforced concrete slab under two-point explosion load are proposed. The results show that there is a phenomenon of energy accumulation in two-point contact explosion. At the same charge, the failure characteristics and dynamic response of RC slabs are related to the distance between the blast points. When the distance is small (30cm), the stress wave encounters and superposition strengthens between the blast points. When the spacing is large (60cm), the stress waves do not meet between the burst points, but reach the back burst surface and the side of the plate at the same time, and the damage is serious near the side of the plate, and the peak acceleration is small.
Experimental study on head loss coefficients of tailrace surge tank for Baihetan hydropower station
Authors: Sun Hongliang , Yang Fei , Cai Fulin , Chen Yimin , Xu Jianrong 
Published: March 2022

Abstract
The scale and hydraulic inertia of the tailrace surge tank of Baihetan hydropower station are huge. Its resistance characteristics are directly related to the accuracy of the calculation results of the hydraulic transient process, the stability of the unit operation, the economy and safety of the project. The influence of split ratio, cross-sectional area of the restricted orifice and unit operation on the head loss coefficient of Baihetan surge tank was studied by model experiment method. The results show that the head loss coefficient increases with the increase of split ratio and decreases with the increase of the cross-sectional area of the restricted orifice. Under the diffluence condition, the head loss coefficient of the restricted orifice in double unit operation is obviously larger than that in single unit operation. Under the confluence condition, the head loss coefficients of the restricted orifice in single and double unit operation are the same. The deviation will be large when using the recommended value in the specification, the experimental results are more reasonable. The research conclusions will provide technical support for the design and operation of Baihetan hydropower station as well as reference for similar projects.
Design and Simulation of LLC Resonant Converter for Hydrogen Production Based on Proton Exchange Membrane Electrolysis
Authors: Zhang Haifeng , Fan Zerui , Zhou Jinghua , Shen Ze 
Published: March 2022

Abstract
This paper studies the relationship between the parameters in LLC resonant circuit based on the fundamental wave analysis method, analyzes the gain curve and the soft-switching conditions of the power tube, gives the selection method of the parameters k and Q and calculates the resonant component parameters. In this paper, a closed-loop frequency modulation control method is used to control the DC output voltage of the resonant converter. At the same time, mathematical modeling and analysis are carried out for the electrochemical model and thermal model of the proton exchange membrane (PEM) hydrogen production electrolyzer, and the Simulink simulation tool is used to complete the joint simulation of the PEM electrolysis model and the LLC resonant converter. The simulation results fully reflect the actual control process.
Analysis for Gas in Transformer Oil based on improved GM (1, N) Grey
Authors: Zhu QiFei , Lv ZhaoPeng , Liu LiPeng , Zhang Jing , Lou Gao , Tian XingJun 
Published: March 2022

Abstract
Based on the traditional gray GM (1, N) model, with seven kinds of gas fusion in transformer oil predicted, the actual detection times for the gas is less, the sequence accuracy is greatly reduced with an large error, and it will not conform to the standard judgment for the smooth curve. Therefore, an adaptive regression algorithm is proposed to revise each calculation result of its GM model to modify the model error. Through simulation, the sequence curves of the N data by error correction are obviously closer with a greater correlation degree. The improved gray prediction model can effectively improve the accuracy of traditional GM (1, N).
Research and Demonstration of Intelligent Multi-Physical Quantity Integration Sensor for Transmission Lines
Authors: Wei Liang , Li Yongcheng , Cui Zhimei , Wang Baoshi , Huang Guanlang , Wang Zhiming , Wei Jie 
Published: March 2022

Abstract
The digital grid requires sensors to be widely deployed, safe, and reliable. At present, the single functional sensors suffered from redundant sensing system, repeated construction and low utilization rate. Therefore, this paper researched the multi-physical quantity integration sensor for a quad-bundle spacer on 500kV transmission lines. The sensor was composed of self-supplying rings and the monitoring host. Based on the non-contact current measurement technology, energy supply technology, intelligent sensing technology, low power consumption technology, reliability design technology, and other advanced technologies, this paper designed the hardware, software, and protective structure of the sensor, which can monitor the current and temperature of bubbles, channel side image and infrared image on transmission lines, ambient temperature, humidity, and air pressure. Finally, the multi-physical quantity integration sensors have been used on transmission lines in China Southern Power Grid, and the functions were verified. The sensors promote the automation, information, and digitization of monitoring transmission lines.
Finite Element Analysis and Optimization of the Planar Steel Tubular K-Joints
Authors: Chen Ying , Yang Qingtao , Wang Dongchen 
Published: March 2022

Abstract
Planar steel tubular K-joints feature various geometric forms and intricate load states, whose bearing capacity is influenced by a number of factors. To address the problems above, a research on the bearing capacity of common planar K-joints in practical engineering projects was conducted. Based on numerical simulation, nonlinear finite element analysis on four kinds of planar K-joints was carried out in ANSYS. The bearing capacity and failure modes of those K-joints were figured out. The bearing capacity of each combination was compared. The results provided by finite element analysis was compared with those derived from codes. The design of K-joints was optimized, thereby improving the bearing capacity and satisfy requirements of engineering projects.
Low power optimization method for contactless micro intelligent voltage sensor communication network
Authors: Sun Hongdi , Chen Renze , Zhou Ke , Wang Xiaoming 
Published: March 2022

Abstract
Aiming at the problems of high power consumption and low success rate in contactless micro voltage sensor communication network, a low power consumption optimization method of contactless micro voltage sensor communication network is proposed. By calculating the average power consumption of micro voltage sensor nodes in the communication network area, the energy balance degree of micro voltage sensor nodes is obtained. When the micro voltage sensor nodes meet the sleep probability of communication network area coverage factor, the power consumption of voltage sensor communication network is calculated. By defining the information entropy of communication network data set, the conditional entropy of data feature classification of communication network is obtained, and the high-power data is eliminated by using the validity kernel function of data features. Combined with the low-power optimization algorithm of micro voltage sensor communication network, the low-power optimization of micro voltage sensor communication network is realized. The experimental results show that the optimization method in this paper can not only reduce the power consumption of data transmission in contactless micro voltage sensor communication network, but also improve the success rate of data transmission, and has better optimization effect.
The CMS HGCAL silicon region architecture specification and optimisation
Authors: Noy M. 
Published: March 2022

AbstractAn overview of the electronics readout/trigger architecture for the CMS HGCAL will be given. To respond to physics performance requirements, data rates, trigger-primitive generation and radiation tolerance has been extremely challenging. Each HGCAL endcap includes ∼300 m2of active silicon in 50 layers, with a largely inhomogenous layout with limited commonality between layers. An agile, python-based counting scheme was implemented that creates tables of component counts. These are subsequently incorporated in the architecture specifications document and costbook, providing critical input to the mechanical design and integration optimisation.