bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fault properties identification scheme for hybrid MTDC system based on LCC signal injection and distributed parameter line model
Authors: Junjie Hou , Guobing Song , Yanfang Fan 
Published: July 2023

AbstractA fault properties identification scheme for a hybrid multi‐terminal DC (MTDC) system is proposed to improve the power supply reliability in the system recovery stage. Firstly, a current signal injection strategy based on line commutated converter (LCC) is proposed using the fault control capability. Secondly, the difference between the calculated value (CV) and the measured value (MV) of the current signal under permanent and temporary faults is analyzed for the distributed parameter line model. By introducing the dynamic time warping (DWT) algorithm to represent the difference between CV and MV, a fault properties identification scheme for permanent fault identification is constructed. Finally, the proposed scheme for permanent fault location with the distributed parameter model is obtained by introducing the trust region reflection (TRR) algorithm. The simulation results show that the proposed fault properties identification scheme has the function of permanent fault identification and location. The proposed scheme fully considers the effects of fault impedance, sampling rate, noise, and data loss. It can be applied to high voltage DC long‐distance transmission lines with LCC.
Hybrid railway vehicle trajectory optimisation using a non‐convex function and evolutionary hybrid forecast algorithm
Authors: Din Tajud , Tian Zhongbei , Bukhari Syed Muhammad Ali Mansur , Hillmansen Stuart , Roberts Clive 
Published: July 2023

AbstractThis paper introduces a novel optimisation algorithm for hybrid railway vehicles, combining a non‐linear programming solver with the highly efficient “Mayfly Algorithm” to address a non‐convex optimisation problem. The primary objective is to generate efficient trajectories that enable effective power distribution, optimal energy consumption, and economical use of multiple onboard power sources. By reducing unnecessary load stress on power sources during peak time, the algorithm contributes to lower maintenance costs, reduced downtime, and extended operational life of these sources. The algorithm's design considers various operational parameters, such as power demand, regenerative braking, velocity and additional power requirements, enabling it to optimise the energy consumption profile throughout the journey. Its adaptability to the unique characteristics of hybrid railway vehicles allows for efficient energy management by leveraging its hybrid powertrain capabilities.
Analytical prediction and analysis of the detent force with the feedback harmonics for the direct drive motion system
Authors: Yang Xiaojun , Shi Anyu , Xuan Jianlin , Yang Zhaohui 
Published: July 2023

AbstractIn the direct drive motion system, there are obvious feedback harmonics caused by the various disturbances, which have important influence on the thrust characteristics of the permanent magnet synchronous linear motor (PMSLM). This paper presents the influence of the feedback harmonics on the detent force for the direct drive motion system. Firstly, the Maxwell's equation and the Schwarz–Christoffel (SC) mapping‐based method are used to accurately establish the magnetic field model in the air‐gap considering the slotting effect and end effect. Then, based on the control model of the motion system, the drive current caused by the feedback harmonics are calculated considering the non‐linearity of the drive circuit. The detent force of PMSLM is analytically represented and analyzed. Finally, the validity of the theoretical analysis is verified by the finite‐element method (FEM) and experiments. The results shown that the feedback harmonics will be coupled with the detent force and intensify the couplings among different sources of the thrust harmonics, which will lead to new coupled thrust harmonics, deteriorating the dynamic precision of the direct drive motion system.
An aerial targets grouping method based on relation network
Authors: Liang Futai , Zhou Yan , Dong Jialong , Chen Xin , Tang Xiao 
Published: July 2023

AbstractAerial targets grouping is an important content of air battlefield situation awareness, and intelligent aerial targets grouping is an urgent need for intelligent air combat. Traditional aerial targets grouping methods have problems such as difficulty extracting air target features, difficulty designing formation similarity measures, and lack of data samples. To solve the above problems, this paper proposes a relational network based aerial targets grouping method to achieve end‐to‐end grouping under small sample conditions. Firstly, an adaptive clustering algorithm is proposed to preliminarily cluster the aerial targets in the air battlefield situation to obtain the group to be tested. Then, a representation of aerial target groups is designed, which unifies the multi‐dimensional features of the group's temporal, spatial, and attribute. Next, based on this representation, combining 3D convolutional neural networks (3DCNN) and long short‐term memory (LSTM), a neural network structure that can automatically extract multi‐dimensional features of groups is designed. After that, the relation module is used to learn the distance metric between groups. After training the relation network, the type of group to be tested can be identified, thereby achieving the goal of grouping. A dataset of 30 types of aerial target group patterns was established through simulation. The ablation experiments were conducted to verify the performance of each module, and the experimental results showed that the designed feature extraction module can effectively extract temporal sample features, while the designed relationship module performs better in extracting temporal sample information. By comparing several typical traditional aerial target grouping methods, the proposed method improves the grouping accuracy by 11.2% to 13.4%, achieving an accuracy of 91.1% in the 5‐way 1‐shot task and 95.6% in the 5‐way 5‐shot task.
Comparison of the Arterial PaCO2 Values and ETCO2 Values Measured with Sidestream Capnography in Patients with a Prediagnosis of COPD Exacerbation
Authors: İşat Gökhan , Cimilli Öztürk Tuba , Ecmel Onur Özge , Özdemir Serdar , Ünal Akoğlu Ebru , Tokgöz Akyıl Fatma , Kuzu Okur Hacer 
Published: July 2023

Abstract
Background Aim of this study is to investigate whether end-tidal carbon dioxide (ETCO2) values can be used instead of partial pressure of carbon dioxide (PaCO2) values in guiding treatment, and determining treatment benefits in patients that received a pre-diagnosis of chronic obstructive pulmonary disease (COPD) exacerbation at the emergency department.
Methods This observational prospective study was conducted with patients who presented to the emergency department with the complaint of shortness of breath and were diagnosed with COPD exacerbation. ETCO2 was measured with the sidestream method during blood gas analysis in patients with indications for this analysis. Measurements were repeated at hour 1 after treatment.
Results The study included a total of 121 cases. There was a positive correlation between the PaCO2 and ETCO2 values measured before and after treatment (r = 0.736, p < 0.01 and r = 0.883, p < 0.01, respectively). High ETCO2 values were accompanied by high PaCO2 values. When the measurements before and after treatment were evaluated using the Bland–Altman method, most of the result were within the limits of agreement (−4.9 and +31.4/− 2.6 and +9.4), with mean differences being calculated as 13.2 and 8.4, respectively.
Conclusions Although ETCO2 and PaCO2 were statistically consistent according to the results of our study, due to the high averages of differences between these two parameters, the ETCO2 value has limited clinical use in COPD cases compared to PaCO2. However, high ETCO2 values may indicate that noninvasive mechanical ventilation should be included in the treatment of COPD cases without waiting for the results of blood gas analysis, and they can also be when needed for inpatient treatment.
Ukrainian refugees struggling to integrate into Czech school social networks
Authors: Lintner Tomáš , Diviák Tomáš , Šeďová Klára , Hlado Petr 
Published: July 2023

AbstractWe provide a brief insight into the integration of Ukrainian refugees in school social networks in the Czech Republic following the mass migration caused by the Russian invasion of Ukraine. Our sample contains twelve classrooms with a total of 266 students in grades 5 to 9; 21.05% of the students were of Ukrainian origin. We employed multiplex exponential random graph modelling to assess the level to which Ukrainian refugees were integrated within peer networks, capturing both friendship and exclusion ties. We then employed a meta-analytical procedure to aggregate the results from the individual classrooms and a meta-regression to study the relationship between classroom ethnic composition and the level of integration of Ukrainian refugees. We found social networks to be formed heavily along ethnic lines with strong ethnic homophily in friendship ties and a propensity of the Ukrainian students to both send and receive fewer friendship ties than their Czech classmates. We found no evidence that the Ukrainian students sent or received more exclusion ties than their Czech classmates, suggesting that the Ukrainian students did not face explicit rejection from classmates; rather, we saw a tendency of the Ukrainian students to be neglected. Our findings stand in contrast to reports from school headmasters who asserted that the social integration of Ukrainian students was seamless. We further found a higher proportion of Ukrainian students in classrooms to be related to stronger homophilic behaviour and a lower tendency of Ukrainian students to make friends. Our results therefore imply that increased classroom diversity may negatively influence the integration of refugees in social networks.
Bandgap narrowing in zincblende III–V semiconductors: Finite-temperature full random-phase approximation and general analytical model
Authors: Schenk A. 
Published: July 2023

The bandgap narrowing (BGN) in zincblende III–V semiconductors is calculated in a finite-temperature full Random-Phase Approximation (RPA) formalism based on an isotropic dispersion model. The cases of n-type and p-type quasi-neutral regions and the case of a neutral electron–hole plasma are elaborated for the technologically important materials GaAs, AlAs, InAs, GaP, InP, GaSb, InSb, zb-GaN, zb-InN, Al0.3Ga0.7As GaAs0.5Sb0.5, InP0.69Sb0.31, InAs0.4P0.6, InAs0.4Sb0.6, In0.52Al0.48As In0.49Ga0.51P, In0.53Ga0.47As In0.5Ga0.5Sb, and zb-Ga0.5In0.5N (60 cases). In quasi-neutral regions, the correlation energy of the interaction between carriers and ionized dopants adds two terms to the total BGN. At low temperatures, inefficient screening makes the hole term dominant in n-type materials with a large ratio of the valence band to the conduction band (CB) density-of-states. The inclusion of the CB nonparabolicity is decisive here, as it prevents a diverging BGN at high concentrations. For all 60 cases, the BGN is evaluated in the temperature range from 0 to 500 K. A strong temperature dependence over the whole density range is observed in all direct n-type materials. Otherwise, the temperature dependence quickly ceases with increasing density. An analytical model of BGN without material-dependent free fit parameters is derived and compared with the full-RPA results.
From crushes to squishes
Authors: Fine Julia Coombs 
Published: July 2023

AbstractPrevious research on language, sexuality, and affect has focused primarily on the presence rather than the absence of desire. This analysis investigates the linguistic manifestations of non-desire on two subreddits:r/AskRedditandr/Asexual. Contrasting asexual redditors’ responses to threads such asWhen and how did you realize you were asexual?with straight, allosexual redditors’ responses to a thread titledStraight redditors, when did you realize you were straight?, I find that allosexual and asexual redditors’ responses differ in agency and emotionality. While straight allosexual redditors attribute their lack of homosexual desire to factors other than themselves, asexual redditors attribute their lack of allosexual desire to their own identity. Additionally, asexual redditors frame their realizations of their asexuality as processual and emotional, usingfeelandfeltmore often than straight allosexual redditors’ responses. These results expose the importance of emotionality – including lack of desire – as a resource for asexual identity construction.
Research on Thermal Insulation Characteristics of Thermal Barrier Coating Materials Based on Human-Machine-Environment Engineering
Authors: Wang Cuicui , Hou Qingqing , Wei Zhenbiao 
Published: July 2023

Abstract
Aiming at the problem that automotive human-machine-environment engineering research the temperature in the vehicle is too high to restrict the working efficiency of personnel and the comprehensive performance of the vehicle. This paper expounds the essence of human-machine-environment engineering research, analyzes the current research status of thermal barrier coating materials, compares and analyzes the thermal insulation performance of thermal barrier coating materials at various stages, and verifies the thermal insulation characteristics of thermal barrier coating materials through experiments, which provides a theoretical reference for the research of human-machine-environment engineering in the automotive field.
Study on the effect of high temperature heat treatment of H2 on the pore structure of activated carbon
Authors: Tao Hongbo , Song Shuai 
Published: July 2023

Abstract
As a high-quality adsorbent, activated carbon is widely used in air purification, natural gas storage, sewage treatment, gas enrichment, and separation, etc. The pore microstructure of activated carbon directly affects the adsorption capacity. In this paper, the altered in the microstructure of activated charcoal before and after high-temperature treatment were investigated by high-temperature thermal treatment of activated charcoal at 600°C and 700°C under an H2 atmosphere. The results of low-temperature (77 K) nitrogen adsorption showed that after high-temperature H2 heat treatment, the pores of activated carbon would be ablated and the pore structure would be significantly changed. The specific surface area, micropore specific surface area, total pore volume, and micropore pore volume all increased, and the degree of enhancement was proportional to the temperature of the heat treatment. The pore size distribution of activated charcoal before and after heat treatment was analyzed by density functional theory, and it was concluded that the pore volume of activated carbon mesopores (2-4 nm) increased significantly after high-temperature heat treatment, which could effectively improve the adsorption and separation capacity of activated carbon in larger molecular systems.
Study on Adsorption Behavior of Sustained-release Polycarboxylate ether Molecules using Molecular Dynamics Simulation
Authors: Lin Xiaochen 
Published: July 2023

Abstract
At present, many experimental studies have focused on the mechanism of performance of sustained-release polycarboxylate ether (PCE), but research on it from a microscopic perspective is still lacking. In this study, molecular dynamics simulation was used to conduct theoretical calculations on the molecular conformation and adsorption behavior of slow-release polycarboxylate ether molecules on the surface of cement lattices, trying to explore the mechanism of slow-release PCE molecules from a microscopic perspective. There are three groups of research design models, which are PCE molecules with ester groups with different degrees of ester group hydrolysis. The three groups of models are used to simulate the adsorption of C3S on the surface of cement particles at three temperatures of 274, 298, and 318 K, and the various parameters of the analysis model. The interpretation of the simulation results shows that the temperature factor and the hydrolysis degree of the ester group will affect the adsorption behavior of the slow-release PCE molecules in different degrees and different aspects.
Molecule Dynamics Simulation of the Effects of Temperature and Vacancy Defects on the Eutectic Sensitivity of CL-20_TNT
Authors: Chen Qing-ci , Chen Fang 
Published: July 2023

Abstract
For contemporary applications, CL-20’s energy density is the highest of any explosive, but it has a very high susceptibility and very low stability. Eutectic techniques can successfully lower CL-20’s susceptibility. However, the eutectic susceptibility can be significantly impacted by the high temperature and many flaws found in its manufacture. By removing CL-20 molecules in Materials Studio (MS) using a molecular dynamics approach, a CL-20/TNT eutectic model with various vacancy concentrations was created in this study. Equilibrium state simulations of the model were run at various temperatures to determine the corresponding kinetic parameters. The susceptibility of CL-20/TNT eutectic-containing vacancy defects is found to increase with the increase in defect concentration and with the increase in temperature, which guides the study of CL-20’s stability and the reduction of susceptibility methods in engineering preparation. Cohesive energy density and binding energy are used at the molecular level as the evaluation criteria of the susceptibility at the macroscopic level.
Parameters Analysis on Flexural Strength of Sisal Fibre Reinforced Mortar: the Effect of Fiber Length
Authors: Huang Jun , Qiu Shichun , Zhang Qianzheng , Fang Kai 
Published: July 2023

Abstract
Sisal fibre is an environmentally degradable material, with a higher tensile strength, it is often used to improve the mechanical properties of cement-based composites. To investigate the influence of sisal fibre size on the mechanical strength of mortar, first, the sisal fibre fraction was kept constant (0.13 wt.%), several different lengths (0 to 40 mm) of sisal fibre were mixed into the mortar matrix, the flexural test results showed that the optimum sisal fibre length was 30 mm. Second, the regression analysis was conducted to further research the influence of sisal fibre length on the flexural strength at varied curing ages (7, 14, and 28 days), and the related shape and scalar parameters to predict the flexural strength of composites were attained. Finally, with the fitting parameters, the corresponding probability density functions were determined. From the fitting results, it showed that the lnln(1/p) was linearly correlated to the ln(fb), and the sisal fibre length may increase the scatter of the experimental data.
Study on Synthesis and Performance of Methyl Diphenyl Urea Stabilizer
Authors: Xia Ping , Jiang Xiabing , Cheng Xiulian , Ma Li , Chang Shengquan , Wang Fei , Zhao Yuanyu , Qiang Zhiduo , Fu Yu 
Published: July 2023

Abstract
Diphenylamine (DPA), formyl chloride, and sodium hydride (NaH) as raw materials synthesize methyldiphenylurea stabilizer by alkylation reaction. The physical and chemical properties of methyldiphenylurea were characterized by nuclear magnetic resonance hydrogen spectrum (1HNMR), X-ray energy spectrum (EDS), Fourier transforms infrared spectroscopy (FT-IR) and differential thermal analysis (DTA). Thermal Decomposition Experiment of Nitrate Propellant Containing Stabilizer by Thermogravimetric Analysis (TGA), exploring the Effect of Different Stabilizers. The molecular surface electrostatic potential energy of methyl diphenyl urea, triphenylamine ( TPA ), dimethyl diphenyl urea (C2), and glycerol trinitrate were calculated by Materials Studio software. The interaction between the stabilizer and glycerol trinitrate molecule was studied. The results showed that the weight loss rate of methyl diphenyl urea was less than 0.1 % within 30 days, and the chemical stability was good. And its negative electrostatic potential energy is larger than that of C2 and TPA, its intermolecular binding ability with glycerol trinitrate is stronger, and its inhibition of nitrate decomposition stability is the best.
Study on Preparation and Mechanism of Concrete Slump Retaining Agent
Authors: Guan Mengqin 
Published: July 2023

Abstract
Using acrylic acid and polyether polymer as the main raw materials, with hydroxyethyl acrylate monomer free radical copolymerization of polycarboxylic acid slump inhibitor, has the effect of reducing the slump loss of concrete. The slow release rate of concrete slump retaining agent synthesized with different ester ratios was studied, and the effects of different ester ratios, different ester ether ratios, and different ambient temperatures on the dispersion, dispersion retention, and hydrolysis rate of polycarboxylic acid slump retaining agent were systematically studied. The knowledge basis for the development of the slump-retaining agent with different sustained release effects. In engineering applications, the working performance of concrete can be controlled more effectively according to the length of the slow release time.
Synthesis and Properties of a New Clay-resistant Polycarboxylic Acid Water Reducer Research
Authors: Jiang Zhuojun , Xiong Qiumin , Chen Xiaobin , Fang Yunhui 
Published: July 2023

Abstract
Due to the shortage of high-quality natural sand, the development of the polycarboxylic acid water reducer with excellent clay resistance has become a research hotspot in recent years. Using acrylic acid, methyl 4-vinylbenzoate, ethylene glycol monovinyl polyethylene glycol ether with a molecular weight of 3000 (EPEG-3000) as comonomers, under the action of sodium bisulfite formaldehyde-hydrogen peroxide redox initiator system initiating system and chain transfer agent mercaptoethanol, a new clay-resistant polycarboxylic acid water reducer with excellent performance was synthesized, named as KZJ-KN. KZJ-KN has the characteristics of high monomer conversion, small adsorption capacity on clay and excellent anti-sludge performance.
Research of Indoor Methane Mass Fraction and Explosion Hazard Prediction Model Based on EKF
Authors: Sun Jingwen , Li Xiaobin , Li Xinhui , Li Quanjun 
Published: July 2023

Abstract
In order to realize the intelligence of the indoor methane supervision system and to deeply analyze and apply the data collected by sensor devices, this paper predicts the indoor methane mass fraction by extended Kalman filter and realizes the prediction of explosion consequences by TNT equivalent method, so as to establish an indoor methane warning model for data collection and analysis. And taking a room of 3×3×3m3 as an example, the indoor natural gas leakage is simulated by CFD, and the data of methane mass fraction change with time is obtained for model simulation and explosion consequence prediction calculation. It is found that the Kalman filter can predict the dynamic change of methane in the room, and the methane concentration in the room gradually reaches the equilibrium state after 10,000s, and the concentration is stable at 3%. The calculation results can provide direction for the accident investigation and provide reference for the decision of accident disposal.