bluuebunny/crossref_metadata_2025_split huggingface dataset:
Collision Avoidance Strategy for Self-Driving Vehicles Based on Drivers and Environmental Factors
Authors: Zhao Yibing , Li Bin , Xiang Xiumei , Guo Lie 
Published: April 2022

Abstract
In order to enhance the driving safety, various driving assistant systems are gradually developed and widely used. Based on the safe distance model related to the braking process, one warning/dangerous critical distance model for longitudinal control is proposed in this paper, considering the driver’s style and environment factors. The variable driver response time is obtained by employing fuzzy control theory. The author then establishes the vehicle dynamics model and its inverse model. Through the relative distance error and relative speed error, the upper controller is designed to obtain the expected acceleration based on sliding mode control, and the lower controller based on PID control is designed to track the acceleration. In order to solve the chattering problem of sliding mode controller, the author proposes variable gain coefficient control method. The fixed gain parameter in the expected acceleration formula is related to the negative exponential correlation formula, which can effectively depress the chattering of the expected acceleration. Finally, the author uses CarSim and Simulink to establish a co-simulation model of the collision avoidance warning system, and designs the test simulation conditions for typical traffic test scenarios to verify the control algorithm effectiveness.
Method for Day-head Operations of a Large Hydropower Plant Considering Peak-shaving Demands of Multiple Provincial Power Grids
Authors: Liu Shuangquan , Zhao Zhenyu , Shen Jianjian , Zhang Ran , Wang Yue 
Published: April 2022

Abstract
Large hydropower plants in China are usually required to transmit power to multiple provinces and meet their complex peak-shaving demands. How to model and solve this problem is challenging. Based on a Hydropower Project in southwest China, this study proposed a method for day-head operations of large hydropower plant considering peak-shaving demands of two provincial power grids. A short-term peak-shaving model for multiple power grids is constructed, which takes the minimum sum of the squares of the remaining loads of each power grid. This model considers complex constraints such as the operation of hydropower plants and the requirements of power transmission. The multi-objective optimization is transformed into a single-objective problem and solved by a group search algorithm based on the genetic algorithm. Two cases which respectively consider different loads and objective weights are presented to test the model. It is found that the large hydropower plant can simultaneously respond to different peak loads for multiple power grids. It should be also noted that different objective weights may have a significant effect on peak-shaving results.
Observation of X-rays during heating a pyroelectric crystal by an infrared laser
Authors: Nazhmudinov R M , Kubankin A S , Oleinik A N , Klenin A A 
Published: April 2022

Abstract
A pyroelectric X-ray source is proposed, in which a lithium tantalate crystal is heated by an infrared laser with a wavelength of 10.6 μm. X-ray spectra measured during irradiation of the crystal with infrared radiation and during natural cooling of the crystal include characteristic X-ray radiation of atoms contained in the structural parts of the source, as well as bremsstrahlung of electrons with energies above 50 keV. An 8 mm sodium chloride window was used to inject 64 W infrared radiation into a vacuum chamber with the pyroelectric crystal installed.
Environmentally friendly synthesis of silicon dioxide nanoparticles and their application for the removal of emerging contaminants in aqueous media
Authors: Tejedor Jennifer , Guerrero Victor H. , Vizuete Karla , Debut Alexis 
Published: April 2022

Abstract
The highly detrimental potential effects that emerging contaminants have for the environment and human health demand the development of sustainable technologies to eliminate these pollutants. In this work, an eco-friendly approach was followed to synthesize S1O2 nanoparticles to be used to remove caffeine and triclosan from synthetic waters. Rice husk was the precursor used, which was subjected to acid leaching treatments using acetic and oxalic acids, and pyrolysis for 2 h at 700 °C. The resulting powders were characterized by X-ray diffraction, Raman and infrared spectroscopies, the Brunauer-Emmett-Teller method, and scanning and transmission electron microscopy. The particles synthesized were amorphous, had an average size between 4.6 and 9.6 nm, and specific surface areas between 208 and 223 m2/g. The adsorptive performance of the nanosilica obtained using acetic acid was studied by batch tests. The optimum dosage, maximum removal efficiencies and maximum adsorption capacities were 8 g/L, 76%, and 2.74 mg/g, and 24 g/L, 48%, and 0.75 mg/g for triclosan and caffeine, respectively. The data collected fitted the Sips isotherm model, and the pseudo-second and -first order kinetics models, for triclosan and caffeine, respectively. The promising results obtained open the possibility of using the synthesized nanomaterials for removing a variety of toxic and recalcitrant pollutants.
On the low star formation rate in Saggitarius C
Authors: Karen Martínez A. , López Ericson 
Published: April 2022

Abstract
The Central Molecular Zone (CMZ) contains approximately 10% of the total molecular gas in the Galaxy concentrated in turbulent and dense molecular clouds. The fact that the star formation rate is low in CMZ is an open question, since there is a large amount of dense gas clouds where star formation could have started. Sagittarius (Sgr) C is the only known star formation region located in the western side of the CMZ. The main goal of our study was to find out the dominant physical conditions of Sgr C and how they could affect the process of star formation in the CMZ. We studied the dust emission toward Sgr C using infrared data. Using radio data we also studied the kinematic temperature, star formation rate surface density and cloud morphology of Sgr C. Our study showed a dust temperature T
d
of approximately 19 K toward Sgr C, which is in agreement with values estimated in other clouds of the CMZ and the Galactic plane. A high kinetic temperature higher than 58 K was determined toward Sgr C, which plays an important role in the cloud fragmentation and subsequent star formation. Based on our radio analysis we found a star formation rate surface density of ∑
SFR
= 4 × 10-3
M
⊙yr-1
kpc
-2 which is lower than in others molecular clouds of the Galaxy. Finally, the HCO
+ emission reveals the presence of cavities and shells in regions where there is no evidence of star formation. These shells could be related to cloud shocks believed to take place in Sgr C. It is thought that cloud shocks may have triggered star formation in other sites of the Galaxy, which is not observed in Sgr C. A comparison between physical conditions in Sgr C with those of high star formation sources could allow to find the parameters that suppress the birth of stars in this region of the Galactic Center.
Effects of movement artifacts in nuclear hybrid modalities for image diagnostic
Authors: Sánchez Jéssica Núñez , Escudero Pedro , Morán Julio Valverde , Roca Julia Garayoa , Río Margarita Chevalier del 
Published: April 2022

Abstract
In the obtention of medical images, the patients’ movement can modify the identification of the body components in an image. The combination of imaging techniques may not always be a solution to improve the imaging quality; therefore, an artifact analysis is commonly required prior to applying an imaging procedure in patients. In this work, we systematically evaluated the movements’ artifacts caused by the patients’ breathing during the images acquisition and their impact on the fusion of SPECT and CT modalities. We used a specific phantom placed on a platform to emulate the respiratory movement, finding artifacts not appreciable under the standard condition used to obtain the SPECT images due to its low spatial resolution. The artifacts produced a deformation of elements on the images. Therefore, image processing was necessary to identify the registration accuracy with SPECT and CT modalities in two states (phantom at rest and for a phantom with simulated respiratory movements). A systematic difference was obtained for the first case (11.7 mm), and a range of (7.4 mm to 16.1 mm) for the second one. For the volumes’ evaluation, the optimal threshold value for CT was 0.40 and for SPECT was 0.25, giving a rapid solution to reduce the artifacts’ impact on medical images.
Design and construction of a low-cost 3D-printed portable LIBS system
Authors: Ormachea O , Villazon A , Oporto O 
Published: April 2022

Abstract
Laser-Induced Breakdown Spectroscopy (LIBS) is a widely used non-destructive analysis technique, which is however costly. In this paper we present the development of a low-cost 3D-printed portable LIBS system designed and built with a Technology Readiness Level 5 (TRL 5), i.e., technology validated in a relevant environment. The proposed LIBS system is compact and includes a passive Q-switch Nd3+:YAG pulsed laser, a handheld measuring device, a power supply, an optical spectrometer and a processing software. The electronic control system guarantees a stable laser triggering, thanks to the use of optical connections (optocouplers) avoiding wired electrical connections of the circuits. In addition, we found the correct energy characteristics of the passive Q-switch regime, to generate a single laser pulse, thus making the system operate more efficiently. Our low-cost 3D-printed portable LIBS system was validated with several tests with real samples of atomic elements (i.e., lithium, copper, silver, gold and lead).
Surface charge distribution characteristics on insulating materials under negative corona in sphere-plane gaps
Authors: Huang Jingwen , Xiu Liancheng , Yue Guohua , Yi Fan , Qi Jin 
Published: April 2022

Abstract
The accumulation of space charge on the insulation surface can affects the distribution of the total electric field. The surface charge distribution characteristics of dielectrics under negative corona have been studied using spherical plate gaps in this paper. In order to measure the surface potential of three insulating materials under the influence of a DC corona by vibrating electrostatic probe. The experiment tested the surface potential of silicone rubber circular specimen and two umbrella-type disks with different curvatures under negative corona in a spherical gap. Afterwards, a new inversion algorithm was proposed in order to convert the surface potential to a surface charge density. Potential spots were found on the surface of silicone rubber, and the degree of charge clustering of umbrella-type disks was positively correlated with curvature. This experiment will serve as a foundation for future research on the surface charge distribution characteristics of insulation in HVDC corona equipment. Meanwhile, it can also be applied to optimize the insulation design.
Exploration of Exoplanets transiting Red Dwarfs within 50 ly of the Sun
Authors: Zhu Xicheng , Liu Jinkun , Jiang Tianlei , Wang Chaohang 
Published: April 2022

Abstract
Many will say that other stars’ sizes are about the same as the Sun’s. That is not quite true. The Sun is known to be a yellow dwarf. However, the most common stars are red dwarfs, the smallest and coolest stars on the main sequence, a continuous band of stars that appears on plots of stellar color versus brightness. Compared to the sun, they are lower in luminosity, making them harder to detect, as the TESS gathers the flux of the stars, directly proportional to the luminosity, the fixed brightness of a star. However, their small size offers key advantages to searching for Earth-like planets. For instance, the habitable zone is closer to the star, making transits easier to detect due to frequency. This work will explore the red dwarfs that are in Jen Winter5’s catalog that we identify to have transiting planets from and present the calculated parameters of the star systems.
Application Analysis of New Technology of Weather Radar in Disaster Prevention and Mitigation Service of Power Grid
Authors: Fan Weinan , Xu Zhong , Liu Junxiang , Wang Yong , Mo Wenxiong 
Published: April 2022

Abstract
Meteorological radar technology has a very important application in power grid disaster prevention and mitigation. Radar technology is used to measure related disaster information, so that people can better take preventive measures and reduce the impact and loss of disasters on the power grid. Using the detection data of meteorological radar, the types of severe weather are automatically identified and divided, and objective short-term nowcasting and forecasting are automatically carried out. The generated early warning products are organically combined with the geographic information system to realize the accurate forecast of short-term severe weather, and accurately locate the power grid equipment through the spatial analysis service engine.
Non-Hermitian Floquet topological phases in one-dimensional system
Authors: Yang Zhengtan , Li Haoze 
Published: April 2022

Abstract
Periodically driven non-Hermitian systems have attracted a lot of attention due to their intriguing topological phases. In this work, we propose a periodically driven non-Hermitian one-dimensional system, which features rich Floquet topological phases. The non-Hermitian Floquet topological phases are characterized by a pair of topological winding numbers, and the non-Hermitian system demonstrates a bulk-edge correspondence.
Long-term stability of the toroidal current measurement at JET using fibre optics current sensor
Authors: Gusarov A. , Leysen W. , Beaumont P. , Boboc A. , Wuilpart M. , Dandu P. , Croft D. , Bekris N. , Batistoni P. 
Published: April 2022

Abstract
The Fibre Optic Current Sensor (FOCS) is a system that will perform plasma current measurements at ITER during long plasma discharges under intense nuclear radiation. These measurements are important for safe machine operation. The FOCS must perform well in a harsh tokamak environment, which include strong magnetic fields, high temperatures, and also significant levels of neurons and high energy photons. JET is a unique machine where the impact of such conditions on the sensor performance can be investigated experimentally in representative conditions. In this work we analyse stability of the fibre Verdet constant using data obtained with two polarisation detection based FOCS systems installed at JET and operated in various machine scenarios with currents up to 4.2 MA. Analysis of data accumulated during more than four years demonstrates that long-term Verdet constant’s changes are less than 0.5%. However, on a month time scale, windows with deviations up to ±9% from the average value are observed. The reason for these windows is unknown at the moment and will be studied in a future.
Simulations of the nEDM@SNS light collection system efficiency
Authors: Loomis D.A. , Cianciolo V. , Leggett E. 
Published: April 2022

Abstract
A system for collecting the scintillation light produced by the capture of ultra-cold neutrons (UCN) on polarized 3He is discussed and results from simulations of its performance are presented. This system will be implemented in nEDM@SNS, the experiment searching for the neutron electric dipole moment (nEDM) at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Simulation results show that the light collection system detects on average 17 photoelectrons per UCN-3He capture event (sufficient to generate a robust signal), reconstructs the event location in the beam direction to approximately 3 cm accuracy, detects capture events with a high and spatially uniform efficiency (0.95 with 1% variation), and rejects greater than 50% of beta decay background events.
Valley-polarized quantum anomalous Hall insulator in monolayer

RuBr2
Authors: Guo San-Dong , Mu Wen-Qi , Liu Bang-Gui 
Published: April 2022

Abstract
The coexistence of an intrinsic ferrovalley (FV) and nontrivial band topology attracts intensive interest, both for its fundamental physics and for its potential applications, namely a valley-polarized quantum anomalous Hall insulator (VQAHI). Here, based on first-principles calculations by using a generalized gradient approximation plus a U (GGA + U) approach, the VQAHI induced by electronic correlation or strain can occur in monolayer

R
u
B

r
2

. For perpendicular magnetic anisotropy (PMA), the FV to half-valley-metal (HVM) to quantum anomalous Hall (QAH) to HVM to FV transitions can be driven by increasing the electron correlation U. However, there are no special QAH states and valley polarization for in-plane magnetic anisotropy. By calculating the actual magnetic anisotropy energy (MAE), the VQAHI can indeed exist between two HVM states due to PMA, a unit Chern number/a chiral edge state and spontaneous valley polarization. The increasing U can induce VQAHI, which can be explained by a sign-reversible Berry curvature or a band inversion between d

xy
/

d

x
2

−

y
2

and

d

z
2

orbitals. Even though the real U falls outside the range, the VQAHI can be achieved by strain. Taking U = 2.25 eV as a concrete case, the monolayer

R
u
B

r
2

can change from a common ferromagentic (FM) semiconductor to VQAHI under about 0.985 compressive strain. It is noted that the edge states of VQAHI are chiral-spin-valley locking, which can achieve complete spin and valley polarizations for low-dissipation electronic devices. Both the energy band gap and the valley splitting of VQAHI in monolayer

R
u
B

r
2

are higher than the thermal energy of room temperature (25 meV), which is key for device applications at room temperature . It is found that the electronic correlation or strain have important effects on the Curie temperature of monolayer

R
u
B

r
2

. These results can be readily extended to other monolayer

M
X
Y

(M = Ru, Os; X/Y = Cl, Br I). Our work emphasizes the importance of electronic correlation and PMA to study FV materials, and provides a pathway to realize VQAHI.
Preparation and characterization of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles via the hydrolysis-combustion-calcination process of iron nitrate
Authors: Liu Tao , Zhang Shuting , Wang Zhou , Xu Yueyang 
Published: April 2022

Abstract
In this work, a feasible and facile hydrolysis-combustion-calcination process of ferric nitrate for the preparation of magnetic α-Fe2O3/Fe3O4 heteroplasmon nanoparticles was represented. The influences of hydrolysis time, hydrolysis temperature, Fe3+ concentration, anhydrous ethanol volume, calcination time, and calcination temperature on the properties of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles were investigated. According to a series of characterization analysis, the optimal preparation conditions were confirmed: 0.05 M Fe(NO3)3·9H2O was hydrolyzed at 90 °C for 8 h, and then the precursor was calcined at 200 °C for 2 h with 20 ml anhydrous ethanol. While, the morphology of α-Fe2O3/Fe3O4 heteroplasmon were spherical structures with the average particle size of about 46 nm, and their saturation magnetization was 54 emu g−1. The α-Fe2O3/Fe3O4 heteroplasmon nanoparticles possessed controllable magnetic properties and a more stable state, which suggested promising applications.
Impact of Cr content on the thermoelectric properties of the Cr/Sb co-doped Mg2.2−xCrx(Si0.3Sn0.7)0.98Sb0.02 compound
Authors: Ju Jia , Fang Mengfei , Cai Hong , Yin Kang , Yan Chen 
Published: April 2022

Abstract
The n-type Cr/Sb co-doped Mg2.2−xCr
x
(Si0.3Sn0.7)0.98Sb0.02 (0.0025 ≤ x ≤ 0.01) compounds were successfully fabricated by applying the solid state reaction-spark plasma sintering (SPS) technique. The impact of the active Cr content on the thermoelectric properties of the co-doped compound was systematically studied. Insights from the x-ray diffraction (XRD) results indicate the existence of single-phase material of the prepared compounds. Interestingly, the lattice constant and the electrical conductivity of the samples increases with the decrease of the Seebeck coefficient as the Cr content is becomes bigger. All the fabricated compounds could achieve an excellent power factor (PF) of 3.8–4.9 mWm−1K−2 in the range of 300–800 K. The lattice thermal conductivity declines with the increasing Cr amount. More specifically, the lowest κ
L
of about 0.5 W∙m−1∙K−1 was obtained while x = 0.01 at 650 K. The figure of merit (ZT) is also reduced by increasing the Cr content. A high ZT value of 1.4 was obtained while x = 0.0025 at 700 K.
Computing equilibrium measures with power law kernels
Authors: Gutleb Timon , Carrillo José , Olver Sheehan 
Published: April 2022

We introduce a method to numerically compute equilibrium measures for problems with attractive-repulsive power law kernels of the form

K
(
x
−
y
)
=

|

x
−
y

|

α

α

−

|

x
−
y

|

β

β

K(x-y) = \frac {|x-y|^\alpha }{\alpha }-\frac {|x-y|^\beta }{\beta }

using recursively generated banded and approximately banded operators acting on expansions in ultraspherical polynomial bases. The proposed method reduces what is naïvely a difficult to approach optimization problem over a measure space to a straightforward optimization problem over one or two variables fixing the support of the equilibrium measure. The structure and rapid convergence properties of the obtained operators result in high computational efficiency in the individual optimization steps. We discuss stability and convergence of the method under a Tikhonov regularization and use an implementation to showcase comparisons with analytically known solutions as well as discrete particle simulations. Finally, we numerically explore open questions with respect to existence and uniqueness of equilibrium measures as well as gap forming behaviour in parameter ranges of interest for power law kernels, where the support of the equilibrium measure splits into two intervals.
Protestantism
Authors: Pearsall Sarah M. S. 
Published: April 2022

Abstract
‘Protestantism’ argues for the importance of polygamy in at least some branches of radical Protestantism. Marriage took on new significance among Protestants as celibacy was no longer upheld as the ideal, and the sacrament of marriage, regulated by the church, increasingly came to be seen as a civil and secular matter. From sixteenth-century events in the German city of Münster to a range of tracts by authors, including Martin Luther and John Milton, to eighteenth-century British treatises by Methodist minister Martin Madan to American Jacob Cochran and his ideas of “spiritual wifery” in the nineteenth century, there have been a range of Protestant defenses of polygamy over the centuries.