bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trajectory Planning for a Mobile Robot in a Dynamic Environment Using an LSTM Neural Network
Authors: Molina-Leal Alejandra , Gómez-Espinosa Alfonso , Escobedo Cabello Jesús Arturo , Cuan-Urquizo Enrique , Cruz-Ramírez Sergio R. 
Published: November 2021

Autonomous mobile robots are an important focus of current research due to the advantages they bring to the industry, such as performing dangerous tasks with greater precision than humans. An autonomous mobile robot must be able to generate a collision-free trajectory while avoiding static and dynamic obstacles from the specified start location to the target location. Machine learning, a sub-field of artificial intelligence, is applied to create a Long Short-Term Memory (LSTM) neural network that is implemented and executed to allow a mobile robot to find the trajectory between two points and navigate while avoiding a dynamic obstacle. The input of the network is the distance between the mobile robot and the obstacles thrown by the LiDAR sensor, the desired target location, and the mobile robot’s location with respect to the odometry reference frame. Using the model to learn the mapping between input and output in the sample data, the linear and angular velocity of the mobile robot are obtained. The mobile robot and its dynamic environment are simulated in Gazebo, which is an open-source 3D robotics simulator. Gazebo can be synchronized with ROS (Robot Operating System). The computational experiments show that the network model can plan a safe navigation path in a dynamic environment. The best test accuracy obtained was 99.24%, where the model can generalize other trajectories for which it was not specifically trained within a 15 cm radius of a trained destination position.
competencias gerenciales en la gestión del cambio de docentes en la unidad de gestión local 01, Perú
Authors: Orihuela Alvino Myriam Diana , Menacho Vargas Isabel , Mauricio Avalos Rubén Moisés , Camarena Mucha José Luis 
Published: November 2021

La presente investigación tuvo como objetivo determinar en qué medida las competencias gerenciales influyen en una gestión direccionada al cambio en el personal docente que labora en una unidad de gestión local. Es por esto que a través de cómo los docentes perciben la función del director con objetivo de cambio, se dieron a conocer las fortalezas y debilidades en las competencias gerenciales. Se ha tomado tomado en cuenta una exhaustiva revisión bibliográfica, con respecto a diferentes estudios realizados en torno a las competencias de los directivos de las organizaciones y de cómo estos, enfocan la gestión del cambio en general. El estudio fue de enfoque cuantitativo, con método correlacional. El diseño de investigación fue no experimental y de corte transversal. Para el recolección de datos se utilizó la encuesta a través de dos cuestionarios, siendo la muestra de 156 docentes, quienes laboran en una unidad de gestión local, a partir de la cual se obtuvo como resultado según el pseudo cuadrado Nagelkerke el 100.0%, por lo que se concluye que las competencias gerenciales influyen de manera directa en la gestión del cambio del personal de la institución en estudio.
IMPROVING ARABIC LANGUAGE LEARNING BASED ON HIGHER ORDER THINKING SKILLS (HOTS) IN EXCELLENT SENIOR HIGH SCHOOL
Authors: Huda Mokhammad Miftakhul , Rais Pandi 
Published: November 2021

Good Arabic learning cannot be separated from the method applied. The curriculum used at MAUDU has already applied K-13, but in fact many some teachers use the classical model. Therefore, a teaching model is necessary that can bring students not only able to answer questions, but also can understand the lessons much better. They can apply the material in their daily lives, analyze and evaluate what has/have been done. This model is known as HOTS (High Order Thinking Skills). This study tries to explain the HOTS system and its relation to Arabic literacy and to innovate the development of HOTS-based materials towards innovative learning. In this study, a descriptive approach, an analytical approach, and a critical approach were used. The results achieved in this study are the innovation of developing HOTS-based Arabic learning which includes several stages, they are basic competency analysis (KD), indicator analysis, student characteristics analysis, formulating learning objectives, material analysis, developing strategies, and learning activities, developing learning tools, developing assessments, linking the principles of HOTS (High Order Thinking Skills), and Revising all aspects and steps of learning development.
Pembelajaran Bahasa Arab yang baik tidak terlepas dari metode yang digunakan. Kurukulum pembelajaran yang digunakan di MAUDU sudah menggunakan K-13, akan tetapi dalam pelaksanaannya banyak yang menggunakan model klasik. Karena itu diperlukan model pengajaran yang dapat membawa siswa tidak hanya sekedar dapat menjawab pertanyaan, tetapi siswa dapat memahami dengan lebih baik, menerapkan materi dalam kesehariannnya, juga dapat menganalisis dan mengevaluasi apa yang telah dikerjakan. Model tersebut dikenal dengan HOTS (High Order Thinking Skills). Penelitian ini berusaha untuk menjelaskan system HOTS dan kaitannya dengan literasi Bahasa Arab dan membuat inovasi pengembangan materi berbasis HOTS menuju pembelajaran yang inovatif. Dalam penelitian ini, digunakan pendekatan deskriptif, pendekatan analisis, dan pendekatan kritis. Hasil yang dicapai dalam penelitian ini adalah Inovasi pengembangan pembelajaran bahasa Arab berbasis HOTS yang meliputi beberapa tahapan, yaitu analisis kompetensi dasar (KD), analisis indikator, analisis karakteristik peserta didik, merumuskan tujuan pembelajaran, analisis materi, mengembangkan strategi, dan kegiatan pembelajaran, mengembangkan perangkat pembelajaran, mengembangkan penilaian, mengkaitkan prinsip HOTS (High Order Thinking Skills), dan Merevisi semua aspek dan langkah pengembangan pembelajaran
Detection of Flare Multiperiodic Pulsations in Mid-ultraviolet Balmer Continuum, Lyα, Hard X-Ray, and Radio Emissions Simultaneously
Authors: Li Dong , Ge Mingyu , Dominique Marie , Zhao Haisheng , Li Gang , Li Xiaobo , Zhang Shuangnan , Lu Fangjun , Gan Weiqun , Ning Zongjun 
Published: November 2021

Abstract
Quasi-periodic pulsations (QPPs), which usually appear as temporal pulsations of the total flux, are frequently detected in the light curves of solar/stellar flares. In this study, we present the investigation of nonstationary QPPs with multiple periods during the impulsive phase of a powerful flare on 2017 September 6, which were simultaneously measured by the Hard X-ray Modulation Telescope (Insight-HXMT), as well as the ground-based BLENSW. The multiple periods, detected by applying a wavelet transform and Lomb–Scargle periodogram to the detrended light curves, are found to be ∼20–55 s in the Lyα and mid-ultraviolet Balmer continuum emissions during the flare impulsive phase. Similar QPPs with multiple periods are also found in the hard X-ray emission and low-frequency radio emission. Our observations suggest that the flare QPPs could be related to nonthermal electrons accelerated by the repeated energy release process, i.e., triggering of repetitive magnetic reconnection, while the multiple periods might be modulated by the sausage oscillation of hot plasma loops. For the multiperiodic pulsations, other generation mechanisms could not be completely ruled out.
Three-dimensional Multispecies Simulation of the Solar Wind Interaction with Mars Under Different Interplanetary Magnetic Field Orientations
Authors: Li Yun , Lu Haoyu , Cao Jinbin , Li Shibang , Mazelle Christian , Li Guokan 
Published: November 2021

Abstract
Without the intrinsic magnetic field, the solar wind interaction with Mars can be significantly different from the interaction with Earth and other magnetized planets. In this paper, we investigate how a global configuration of the magnetic structures, consisting of the bow shock, the induced magnetosphere, and the magnetotail, is modulated by the interplanetary magnetic field (IMF) orientation. A 3D multispecies numerical model is established to simulate the interaction of solar wind with Mars under different IMF directions. The results show that the shock size including the subsolar distance and the terminator radius increases with Parker spiral angle, as is the same case with the magnetotail radius. The location and shape of the polarity reversal layer and inverse polarity reversal layer in the induced magnetotail are displaced to the y < 0 sector for a nonzero flow-aligned IMF component, consistent with previous analytical solutions and observations. The responses of the Martian global magnetic configuration to the different IMF directions suggest that the external magnetic field plays an important role in the solar wind interaction with unmagnetized planets.
Multi-messenger Approaches to Supermassive Black Hole Binary Detection and Parameter Estimation: Implications for Nanohertz Gravitational Wave Searches with Pulsar Timing Arrays
Authors: Liu Tingting , Vigeland Sarah J. 
Published: November 2021

Abstract
Pulsar timing array (PTA) experiments are becoming increasingly sensitive to gravitational waves (GWs) in the nanohertz frequency range, where the main astrophysical sources are supermassive black hole binaries (SMBHBs), which are expected to form following galaxy mergers. Some of these individual SMBHBs may power active galactic nuclei, and thus their binary parameters could be obtained electromagnetically, which makes it possible to apply electromagnetic (EM) information to aid the search for a GW signal in PTA data. In this work, we investigate the effects of such an EM-informed search on binary detection and parameter estimation by performing mock data analyses on simulated PTA data sets. We find that by applying EM priors, the Bayes factor of some injected signals with originally marginal or sub-threshold detectability (i.e., Bayes factor ∼1) can increase by a factor of a few to an order of magnitude, and thus an EM-informed targeted search is able to find hints of a signal when an uninformed search fails to find any. Additionally, by combining EM and GW data, one can achieve an overall improvement in parameter estimation, regardless of the source’s sky location or GW frequency. We discuss the implications for the multi-messenger studies of SMBHBs with PTAs.
Capturing the Physics of MaNGA Galaxies with Self-supervised Machine Learning
Authors: Sarmiento Regina , Huertas-Company Marc , Knapen Johan H. , Sánchez Sebastián F. , Domínguez Sánchez Helena , Drory Niv , Falcón-Barroso Jesus 
Published: November 2021

Abstract
As available data sets grow in size and complexity, advanced visualization tools enabling their exploration and analysis become more important. In modern astronomy, integral field spectroscopic galaxy surveys are a clear example of increasing high dimensionality and complex data sets, which challenges the traditional methods used to extract the physical information they contain. We present the use of a novel self-supervised machine-learning method to visualize the multidimensional information on stellar population and kinematics in the MaNGA survey in a 2D plane. Our framework is insensitive to nonphysical properties such as the size of the integral field unit and is therefore able to order galaxies according to their resolved physical properties. Using the extracted representations, we study how galaxies distribute based on their resolved and global physical properties. We show that even when exclusively using information about the internal structure, galaxies naturally cluster into two well-known categories, rotating main-sequence disks and massive slow rotators, from a purely data-driven perspective, hence confirming distinct assembly channels. Low-mass rotation-dominated quenched galaxies appear as a third cluster only if information about the integrated physical properties is preserved, suggesting a mixture of assembly processes for these galaxies without any particular signature in their internal kinematics that distinguishes them from the two main groups. The framework for data exploration is publicly released with this publication, ready to be used with the MaNGA or other integral field data sets.
Discovery of a New Population of Galactic H ii Regions with Ionized Gas Velocity Gradients
Authors: Balser Dana S. , Wenger Trey V. , Anderson L. D. , Armentrout W. P. , Bania T. M. , Dawson J. R. , Dickey John M. 
Published: November 2021

Abstract
We investigate the kinematic properties of Galactic H ii regions using radio recombination line (RRL) emission detected by the Australia Telescope Compact Array at 4–10 GHz and the Jansky Very Large Array at 8–10 GHz. Our H ii region sample consists of 425 independent observations of 374 nebulae that are relatively well isolated from other, potentially confusing sources and have a single RRL component with a high signal-to-noise ratio. We perform Gaussian fits to the RRL emission in position-position–velocity data cubes and discover velocity gradients in 178 (42%) of the nebulae with magnitudes between 5 and 200

m

s

−
1

arcsec

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1

. About 15% of the sources also have an RRL width spatial distribution that peaks toward the center of the nebula. The velocity gradient position angles appear to be random on the sky with no favored orientation with respect to the Galactic plane. We craft H ii region simulations that include bipolar outflows or solid body rotational motions to explain the observed velocity gradients. The simulations favor solid body rotation since, unlike the bipolar outflow kinematic models, they are able to produce both the large, >40

m

s

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1

arcsec

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1

, velocity gradients and also the RRL width structure that we observe in some sources. The bipolar outflow model, however, cannot be ruled out as a possible explanation for the observed velocity gradients for many sources in our sample. We nevertheless suggest that most H ii region complexes are rotating and may have inherited angular momentum from their parent molecular clouds.
Radiative-dynamical Simulation of Jupiter’s Stratosphere and Upper Troposphere
Authors: Zube Nicholas G. , Zhang Xi , Li Tao , Le Tianhao , Li Cheng , Guerlet Sandrine , Tan Xianyu 
Published: November 2021

Abstract
We present a two-dimensional radiative-dynamical model of the combined stratosphere and upper troposphere of Jupiter to understand its temperature distribution and meridional circulation pattern. Our study highlights the importance of radiative and mechanical forcing for driving the middle atmospheric circulation on Jupiter. Our model adopts a state-of-the-art radiative transfer scheme with recent observations of Jovian gas abundances and haze distribution. Assuming local radiative equilibrium, latitudinal variation of hydrocarbon abundances is not able to explain the observed latitudinal temperature variations in the mid-latitudes. With mechanical forcing parameterized as a frictional drag on zonal wind, our model produces ∼2 K latitudinal temperature variations observed in low to mid-latitudes in the troposphere and lower stratosphere, but cannot reproduce the observed 5 K temperature variations in the middle stratosphere. In the high latitudes, temperature and meridional circulation depend strongly on polar haze radiation. The simulated residual mean circulation shows either two broad equator-to-pole cells or multi-cell patterns, depending on the frictional drag timescale and polar haze properties. A more realistic wave parameterization and a better observational characterization of haze distribution and optical properties are needed to better understand latitudinal temperature distributions and circulation patterns in the middle atmosphere of Jupiter.
The Water-ice Feature in Near-infrared Disk-scattered Light around HD 142527: Micron-sized Icy Grains Lifted up to the Disk Surface?
Authors: Tazaki Ryo , Murakawa Koji , Muto Takayuki , Honda Mitsuhiko , Inoue Akio K. 
Published: November 2021

Abstract
We study the 3 μm scattering feature of water ice detected in the outer disk of HD 142527 by performing radiative transfer simulations. We show that an ice mass abundance at the outer disk surface of HD 142527 is much lower than estimated in a previous study. It is even lower than inferred from far-infrared ice observations, implying ice disruption at the disk surface. Next, we demonstrate that a polarization fraction of disk-scattered light varies across the ice-band wavelengths depending on ice grain properties; hence, polarimetric spectra would be another tool for characterizing water-ice properties. Finally, we argue that the observed reddish disk-scattered light is due to grains a few microns in size. To explain the presence of such grains at the disk surface, we need a mechanism that can efficiently oppose dust settling. If we assume turbulent mixing, our estimate requires α ≳ 2 × 10−3, where α is a nondimensional parameter describing the vertical diffusion coefficient of grains. Future observations probing gas kinematics would be helpful to elucidate vertical grain dynamics in the outer disk of HD 142527.
Dust Rings as a Footprint of Planet Formation in a Protoplanetary Disk
Authors: Kanagawa Kazuhiro D. , Muto Takayuki , Tanaka Hidekazu 
Published: November 2021

Abstract
Relatively large dust grains (referred to as pebbles) accumulate at the outer edge of the gap induced by a planet in a protoplanetary disk, and a ring structure with a high dust-to-gas ratio can be formed. Such a ring has been thought to be located immediately outside the planetary orbit. We examined the evolution of the dust ring formed by a migrating planet, by performing two-fluid (gas and dust) hydrodynamic simulations. We found that the initial dust ring does not follow the migrating planet and remains at the initial location of the planet in cases with a low viscosity of α ∼ 10−4. The initial ring is gradually deformed by viscous diffusion, and a new ring is formed in the vicinity of the migrating planet, which develops from the trapping of the dust grains leaking from the initial ring. During this phase, two rings coexist outside the planetary orbit. This phase can continue over ∼1 Myr for a planet migrating from 100 au. After the initial ring disappears, only the later ring remains. This change in the ring morphology can provide clues as to when and where the planet was formed, and is the footprint of the planet. We also carried out simulations with a planet growing in mass. These simulations show more complex asymmetric structures in the dust rings. The observed asymmetric structures in the protoplanetary disks may be related to a migrating and growing planet.
Extended Calculations of Energy Levels and Transition Rates for Singly Ionized Lanthanide Elements. II. Tb−Yb
Authors: Radžiūtė Laima , Gaigalas Gediminas , Kato Daiji , Rynkun Pavel , Tanaka Masaomi 
Published: November 2021

Abstract
In this work, we continue large-scale ab initio computations for single ionized lanthanides. Extended atomic calculations for the set of ions from Pr ii (Z = 59) to Gd ii (Z = 64) have been performed in our previous work. In this study, ions from Tb ii (Z = 65) to Yb ii (Z = 70) are analyzed. By employing the same multiconfiguration Dirac–Hartree–Fock and relativistic configuration interaction methods that are implemented in the general-purpose relativistic atomic structure package GRASP2018, the energy levels and transition data of electric dipole (E1) transitions are computed. These computations are based on the strategies (with small variations) of Paper I. Accuracy of data is evaluated by comparing the computed energy levels with the data provided by the National Institute of Standards and Technology (NIST) database and with data from various methods. We obtain the average accuracy in the energy level compared with the NIST database: 6%, 5%, 4%, 5%, 3%, and 3% for Tb ii, Dy ii, Ho ii, Er ii, Tm ii, and Yb ii, respectively. We also provide extensive comparison of transition probabilities and wavelengths. Our results reach the average accuracy of transition wavelengths: 9%, 9%, 9%, 3%, 4%, and 11% for Tb ii, Dy ii, Ho ii, Er ii, Tm ii, and Yb ii, respectively.
A Provably Positive, Divergence-free Constrained Transport Scheme for the Simulation of Solar Wind
Authors: Zhang Man , Feng Xueshang , Liu Xiaojing , Yang Liping 
Published: November 2021

Abstract
In this paper, we present a provably positive, divergence-free constrained transport (CT) scheme to simulate the steady-state solar wind ambient with the three-dimensional magnetohydrodynamics numerical model. The positivity can be lost in two ways: one way is in the reconstruction process, and the other is in the updating process when the variables are advanced to the next time step. We adopt a self-adjusting strategy to bring the density and pressure into the permitted range in the reconstruction process, and use modified wave speeds in the Harten–Lax–van Leer flux to ensure the positivity in the updating process. The CT method can keep the magnetic fields divergence-free if the magnetic fields are divergence-free initially. Thus, we combine the least-squares reconstruction of the magnetic fields with the divergence-free constraints to make the magnetic fields globally solenoidal initially. Furthermore, we adopt a radial basis function method to interpolate variables at boundaries that can keep the magnetic field locally divergence-free. To verify the capability of the model in producing structured solar wind, the modeled results are compared with Parker Solar Probe (PSP) in situ observations during its first two encounters, as well as Wind observations at 1 au. Additionally, a solar maximum solar wind background is simulated to show the property of the model’s ability to preserve the positivity. The results show that the model can provide a relatively satisfactory comparison with PSP or Wind observations, and the divergence error is about 10−10 for all of the tests in this paper.
« Let’s get together » : fabriquer du patrimoine partagé, entre bureaucratisation de l’utopie et utopisation de la bureaucratie
Authors: Bortolotto Chiara 
Published: November 2021

Cet article traite de la corrélation entre bureaucratie, idéologies d’échelle et utopie dans la production du « patrimoine partagé » comme incarnation de l’idéal porté par l’UNESCO pour rapprocher les peuples par-delà les frontières physiques et symboliques. L’utopie scalaire de l’UNESCO est explorée en mettant l’accent sur la promotion des « candidatures multi-nationales » à la Liste représentative du patrimoine culturel immatériel. Leur agentivité politique est illustrée par la candidature binationale de la lutte coréenne qui célèbre le partage d’une même culture par des pays rivaux. Ce dispositif est comparé à la rhétorique universaliste des débats qui ont accompagné l’inscription du reggae et du yoga sur la même liste. Une observation participante du dispositif global du patrimoine culturel immatériel met en évidence l’ingéniosité des fonctionnaires du patrimoine dans leur poursuite d’idéaux d’unité : des technologies administratives créant des représentations du patrimoine partagé sont conçues et mises en œuvre dans un processus qui rend l’utopie bureaucratique et la bureaucratie utopique.