bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation and assessment of multi-GNSS phase bias products from IGS analysis centers
Authors: Lyu Zhen , Wang Zhiyu , Li Zishen , Wang Ningbo , Wang Liang , Zhang Yunlong 
Published: January 2024

AbstractPhase bias plays a crucial role in precision point positioning (PPP) with ambiguity resolution. Currently, an increasing number of analysis centers are being of releasing multi- Global Navigation Satellite System (GNSS) phase bias products. However, it remains uncertain how different phase bias products, receiver types, and GNSS systems combinations might impact user-side positioning performance and ambiguity resolution capabilities. In view of this, this contribution systematically investigates the effects on PPP with ambiguity resolution. Four types of receivers, including SEPTENTRIO POLARX5, LEICA GR50, JAVAD TRE_3 DELTA, and TRIMBLE ALLOY, are selected, and six types of GNSS system combinations, namely, GPS, Galileo, BDS3, GPS/Galileo, GPS/BDS3, GPS/Galileo/BDS3, are used, and the phase bias products from OSB (Observable-specific Bias)-CODE (Center for Orbit Determination in Europe), OSB-CNES/CLS (Centre National d’Etudes Spatiales Geodesy Team), OSB-GFZ (German Research Centre for Geosciences/Germany), OSB-WHU (Wuhan University), OSB-CNES/NAV (Centre National d’Etudes Spatiales Navigation Team), IRC (Integer Recovery Clock)-CNES/CLS, IRC-GFZ are adopted for the numerical experiment. Compared with the float-solution, the results show that the accuracy of PPP fixed-solution with single-system can be improved 1 cm–3 cm, and the convergence time is reduced 2 min–15 min. The positioning performance using the seven phase bias products for any single-system satisfies the following order from the best to the worst: OSB_WHU > OSB_CODE > OSB_CNES/CLS ≈ OSB_CNES/NAV > OSB_GFZ > IRC_CNES/CLS ≈ IRC_GFZ, but the performance of ambiguity resolution do not present certain characteristics. Meanwhile, the ambiguity-fix success-rate and Time to First Fix can keep at 80%–96% and 20 min–40 min with single-system, respectively. In the case of multi-system, although the difference in the positioning performance among the phase bias products is not significant, the multi-system outperforms the single-systemin terms of both positioning performance and ambiguity resolution. However, the difference between the dual-system and the triple-system is smaller. In addition, the positioning performance corresponding to different receiver types also shows distinction, while there is no significant difference in the ambiguity resolution performance between different receiver types.
An anti-charge-interference three-dimensional electric field sensor
Authors: Zhang Wei , Xia Shanhong , Peng Chunrong 
Published: January 2024

Abstract
A major concern in the development of three-dimensional (3D) microelectromechanical system electric field sensors (EFSs) is space charge interference. With space charges in the surrounding environment, charges may accumulate at the surface of the EFS, which affects the accuracy of the electric field measurement. There is a lack of relevant mechanism research and solutions for this problem. Here, an anti-charge-interference 3D EFS is presented, which consists of three electric field sensing elements and a reference element. By establishing the model of the sensing element, the relationship of the electric field at the sensing chip with the distance between the sealing cap and the sensing chip is explored. The theoretical basis of the measurement method of the 3D electric field based on a coplanar structure is introduced. Then, the influence of charge accumulation is overcome by a differential calculation between the output signals of the reference element and sensing elements. The anti-charge-interference 3D EFS prototype is developed. Experimental results show that the measurement error of the anti-charge-interference 3D EFS is 4.01% and the linearity is better than 1% under an electric field of 0–50 kV m−1.
Optimization of tensor network codes with reinforcement learning
Authors: Mauron Caroline , Farrelly Terry , Stace Thomas M 
Published: January 2024

Abstract
Tensor network codes enable structured construction and manipulation of stabilizer codes out of small seed codes. Here, we apply reinforcement learning (RL) to tensor network code geometries and demonstrate how optimal stabilizer codes can be found. Using the projective simulation framework, our RL agent consistently finds the best possible codes given an environment and set of allowed actions, including for codes with more than one logical qubit. The agent also consistently outperforms a random search, for example finding an optimal code with a

10
%

frequency after 1000 trials, vs a theoretical

0.16
%

from random search, an improvement by a factor of 65.
Generation and propagation of acoustic solitons in a periodic waveguide of air-water metamaterials
Authors: Braik R , Elmadani A , Idrissi M , Achaoui Y , Jakjoud H 
Published: January 2024

Abstract
In this study, we propose an equivalent circuit of a metamaterial 1D waveguide. The latter is made of a diphasic medium to induce both non-linearity and dispersion. The balance between these two effects makes it possible to obtain soliton waves not studied in the fluid-fluid metamaterial so far. The purpose of the present paper is to confront the numerical Runge Kutta-based solution to the Transmission Line based circuits. The latter is compared to the numerical solution obtained by a Finite element method (FEM) algorithm to validate the numerical solution. The obtained solution is proved to be in good agreement with FEM solution.
ZPW-2000 frequency-shift signal detection algorithm based on nonlinear least squares method
Authors: Ji Guanggang , Shan Mingyang , Li Zheng , Wang Hongkai 
Published: January 2024

Abstract
Aiming at the problems of spectrum leakage, difficulty in guaranteeing demodulation accuracy, and endangering driving safety in signal detection algorithm based on periodogram with limited sampling duration, this paper proposes for the first time a kind of ZPW-20000 frequency-shift signal detection algorithm based on nonlinear least squares, so as to improve the detection performance of ZPW-2000 frequency-shift signal, to ensure the safe operation of trains, and to improve the operational efficiency. The mathematical model of ZPW-2000 frequency-shift signal is established, the Cramér-Rao bound (CRB) for carrier-frequency and low-frequency estimation are derived, and a nonlinear least squares algorithm containing three processes, namely, the coarse estimation, the grid search based on Fast Fourier Transform (FFT), and the exact search, is designed, which is applied to the detection of ZPW-2000 frequency-shift signal. The research results show that the accuracy of carrier-frequency and low-frequency estimation of the proposed algorithm is better than that of the periodogram method for different sampling durations, and the number of decoding errors of the proposed algorithm and the periodogram method is reduced to zero when the sampling durations are greater than or equal to 0.11 s and 0.19 s, respectively, and the proposed algorithm reduces the limitation on the sampling durations. As the signal-to-noise ratio (SNR) increases, the root mean square error (RMSE) of carrier-frequency and low-frequency estimation of the proposed algorithm can approach the CRB. when the SNR of −2 dB, the number of decoding errors of the proposed algorithm is reduced to zero, while the periodogram method requires the SNR of 2 dB to achieve the same effect. The proposed algorithm performs well in detection accuracy, real-time and anti-interference ability, which is of great significance for ensuring driving safety and improving the reliability of the vehicle-ground communication mode based on ZPW-2000 track circuit.
Tunable optical absorption in undoped graphene sandwiched between multilayer dielectric stacks with mirror symmetry
Authors: Kengo Faisal , Solihin S , Shoufie Ukhtary M , Suwardy Joko , Aziz Majidi M , Nugraha Ahmad R T 
Published: January 2024

Abstract
We theoretically investigate the optical absorption of an undoped graphene monolayer when put in a one-dimensional multilayer stack. Using the transfer matrix method, we perform numerical simulations and derive explicit analytical formulas for the optical absorption of the graphene monolayer at the center of the dielectric stack and find that the optical absorption uniquely depends on repetition number (r) and the unit layers structure. When sandwiched between unit layers structure composed of three dielectric materials (referred to as the ‘ABC’ structure) with even values of r, the graphene monolayer absorbs 2.3% of visible to near-infrared light. This behavior is the same as if graphene were free-standing, not sandwiched between the dielectric stack. In contrast to that situation, in the ABC structure with odd values of r, also when the graphene monolayer is sandwiched between four materials (the ‘ABCD’ structure) with any values of r, we can obtain optical absorption as large as 50% at particular refractive indices (n) of the constituent dielectric materials. The 50% absorption is, in fact, the maximum optical absorption for any undoped monolayer material in the symmetric dielectric stacks. By varying r and n within the ABC or ABCD structures, we can finely adjust the optical absorption of graphene within the range of 0%–50%, facilitating precise control for various optoelectronic applications.
Various wave solutions to the nonlinear fractional Korteweg-de Vries Zakharov-Kuznetsov equation by a new approach to the two-variable expansion scheme
Authors: Khatun Mst Munny , Akbar M Ali , Fayazova Zarina K , İlhan Onur Alp 
Published: January 2024

Abstract
Solving nonlinear differential equations is crucial for the design, optimization, and characterization of engineering systems. However, investigating such equations poses significant challenges and requires the development of new mathematical and computational techniques. In this article, we extend the two-variable

(

G

′

/

G

,

1

/

G

)

-expansion approach and establish scores of general analytical solutions, consisting of different functions and arbitrary parameters, to the time-fractional Korteweg–de Vries Zakharov-Kuznetsov (KdV-ZK) equation. The KdV-ZK equation provides a powerful model for modulating nonlinear waves in an assortment of physical systems, including plasma physics, atmospheric science, fluid dynamics, soliton theory, and optical fibers. The proposed technique allows extracting several novel solutions to the KdV-ZK equation, which is essential for gaining new insights into physical problems. In addition, the suggested extension shortens the calculation process and enhances computational efficiency. The obtained solitons have potential applications in several scientific and technological fields. The beta fractional derivative and the consistent wave variable are considered to restructure the stated fractional nonlinear equation. This study investigates the merits and demerits of the fractional-order derivative β on the dynamics of the system through the representation of two-dimensional graphs, which vary according to different values of β. The enhanced computational efficiency might assist the researchers in exploring a wider range of phenomena, facilitating further extensive investigations, and contributing to overall progress in the fields of science and engineering.
Quantum algorithms for matrix operations and linear systems of equations
Authors: Qi Wentao , Zenchuk Alexandr I , Kumar Asutosh , Wu Junde 
Published: January 2024

Abstract
Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific investigations. Using the ‘sender-receiver’ model, we propose quantum algorithms for matrix operations such as matrix-vector product, matrix-matrix product, the sum of two matrices, and the calculation of determinant and inverse matrix. We encode the matrix entries into the probability amplitudes of the pure initial states of senders. After applying proper unitary transformation to the complete quantum system, the desired result can be found in certain blocks of the receiver’s density matrix. These quantum protocols can be used as subroutines in other quantum schemes. Furthermore, we present an alternative quantum algorithm for solving linear systems of equations.
Reconstruction of aether scalar tensor theory for variouscosmological scenarios*
Authors: Fu 付 Qi-Ming 启铭 , He 何 Meng-Ci 梦慈 , Sui 眭 Tao-Tao 陶陶 , Zhang 张 Xin 鑫 
Published: January 2024

Abstract
In this paper, we present several explicit reconstructions for the aether scalar tensor (AeST) theory derived from the background of the Friedmann-Lemaître-Robertson-Walker cosmological evolution. It is shown that the Einstein-Hilbert Lagrangian with a positive cosmological constant is the only Lagrangian capable of accurately replicating the exact expansion history of the Λ cold dark matter (ΛCDM) universe filled solely with dust-like matter. However, the ΛCDM-era can be produced within the framework of the AeST theory for some other fluids, including a perfect fluid with

, multifluids, and nonisentropic perfect fluids. Moreover, we demonstrate that the ΛCDM-era can be replicated with no real matter field for the AeST theory. The cosmic evolution resulting from both the power-law and de-Sitter solutions can also be obtained.
A discussion on the anomalous threshold enhancement of
–
couplings and
peak*
Authors: Lu 陆 Ye 业 , Chen 陈 Chang 畅 , Qin 秦 Guang-You 广友 , Zheng 郑 Han-Qing 汉青 
Published: January 2024

Abstract
The attractive interaction between

and

has to be strong enough if X(6900) is of the molecule type. We argue that since

decays predominantly into a

pair, the interactions between

and

may be significantly enhanced owing to the three point

loop diagram. The enhancement originates from the anomalous threshold located at

GeV

, whose effect propagates into the s-channel partial wave amplitude in the vicinity of

GeV. This effect may be helpful in the formation of the

peak.
Exploring dark matter-gauge boson effective interactions at current and future colliders*
Authors: Zhang 张 Yu 宇 , Huang 黄 Yi-Wei 祎伟 , Zhang 张 Wei-Tao 伟涛 , Song 宋 Mao 昴 , Ding 丁 Ran 然 
Published: January 2024

Abstract
In this study, we systematically investigate collider constraints on effective interactions between Dark Matter (DM) particles and electroweak gauge bosons. We consider the simplified models in which scalar or Dirac fermion DM candidates couple only to electroweak gauge bosons through high dimensional effective operators. Considering the induced DM-quarks and DM-gluons operators from the Renormalization Group Evolution (RGE) running effect, we present comprehensive constraints on the effective energy scale Λ and Wilson coefficients

from direct detection, indirect detection, and collider searches. In particular, we present the corresponding sensitivity from the Large Hadron Electron Collider (LHeC) and Future Circular Collider in the electron-proton mode (FCC-ep) for the first time, update the mono-j and mono-γ search limits at the Large Hadron Collider (LHC), and derive the new limits at the Circular Electron Positron Collider (CEPC).
Long term behavior of the stirred vacuum on a Dirac chain: geometry blur and the random Slater ensemble
Authors: Vinaixa José , Mula Begoña , Deaño Alfredo , Santalla Silvia N , Rodríguez-Laguna Javier 
Published: January 2024

Abstract
We characterize the long-term state of the 1D Dirac vacuum stirred by an impenetrable object, modeled as the ground state of a finite free-fermionic chain dynamically perturbed by a moving classical obstacle which suppresses the local hopping amplitudes. We find two different regimes, depending on the velocity of the obstacle. For a slow motion, the effective Floquet Hamiltonian presents features which are typical of the Gaussian orthogonal ensemble, and the occupation of the Floquet modes becomes roughly homogeneous. Moreover, the long term entanglement entropy of a contiguous block follows a Gaussian analogue of Page’s law, i.e. a volumetric behavior. Indeed, the statistical properties of the reduced density matrices correspond to those of a random Slater determinant, which can be described using the Jacobi ensemble from random matrix theory. On the other hand, if the obstacle moves fast enough, the effective Floquet Hamiltonian presents a Poissonian behavior. The nature of the transition is clarified by the entanglement links, which determine the effective geometry underlying the entanglement structure, showing that the one-dimensionality of the physical Hamiltonian dissolves into a random adjacency matrix as we slow down the obstacle motion.
Project digiSTAR – digital augmented Science Teaching and Research
Authors: Blick Gina , Syskowski Sabrina , Möhrke Philipp , Kannegieser Sören , Huwer Johannes , Thyssen Christoph , Thoms Lars-Jochen 
Published: January 2024

Abstract
This paper introduces the digiSTAR project, whose primary focus is on bridging the digital gap in undergraduate studies, which arises between the now digitalized schools and the technology-driven master’s programs at universities when undergraduate courses are taught in a more traditional and less digitalized way, by providing teaching-learning modules and digital resources. The second goal is to provide pre-service science teachers with authentic learning opportunities for designing and testing lessons and (peer) feedback on their own developments, in accordance with the DiKoLAN framework, which characterizes digital competencies for teaching in science education. Initial results of the first design-based research cycle, based on a survey of first-year chemistry students, showed that chemistry students have difficulty understanding the physical fundamentals of quantum chemistry needed to understand topics such as molecular orbital theory. These challenges can potentially be eased through the implementation of innovative digital modules, which have been and will be created by teacher students enrolled in the Master of Education program. The project digiSTAR aims to establish a collection of digital modules designed for first-year science courses, with the long-term vision of extending this endeavour to encompassing a broader range of academic disciplines to address and reduce the digital gap.
QuVis simulations in Czech - translation and utilization in pre-service physics teacher course
Authors: Koupilová Zdeňka , Kácovský Petr 
Published: January 2024

Abstract
The collection of QuVis simulations is based on research on frequent student difficulties, and their design and effectiveness have been also verified. The concept of these simulations fits very well into our undergraduate Introductory Course of Quantum Physics for pre-service physics teachers. However, due to the simulations being in English, we recognized the language barrier as an obstacle for some students when working independently with them. Moreover, we believe that a solid grasp of Czech terminology is important for future teachers. These reasons led us to translate 20 simulations into Czech. To further enhance the collection, we are developing thematic worksheets that feature tasks using the selected simulations alongside tasks that are solved without their use. Up to now, we have published five worksheets focusing on measurement in quantum physics.
VITAL - A Modular VR & AR Based Educational Toolkit to Help EU Adults Foster Climate Neutral Practices
Authors: Říha Jan , Richterek Lukáš , Hrouzková Tereza , Smrčka David , Bartoněk Luděk , Pucholt Zdeněk 
Published: January 2024

Abstract
The VITAL project is motivated by the EU’s Green Deal Action Plan and the exploitation of two Erasmus+ priorities - the fight against climate change combined with digital transformation, in this case in the adult education sector. Various studies, statistics and surveys show that the rate of natural resource extraction is rapidly growing and our planet and the home of mankind can come to exhaustion of its finite resources. In a nutshell, the behaviour and lifestyle of EU Citizens in terms of consumption and use of products and services need to be influenced so that we all contribute daily actions that are more sustainable and aligned with best practices leading to carbon neutrality. In the contribution, we would like to inform about a course and materials developed within our Erasmus+ project that could serve various target users (adult trainers, schools, NGOs, municipal authorities, etc.) to get information about the principles and provide a set of hands-on activities enriched with AR technology features.
Teaching Refractive index with a Virtual Experimental Activity
Authors: Rodrigues Marcelo , Simeão Carvalho Paulo , Hahn Marcelo 
Published: January 2024

Abstract
The refractive index of a transparent medium is a physical property taught in the schools at the secondary level. It depends on the medium characteristics that can be easily shown with a simple experimental setup. This property also depends on the wavelength of the light and on the temperature of the medium. These dependencies are very smooth and schools usually do not have accurate experimental setups to allow students exploring the dependency in order to better understand this phenomenon. This work presents a simulation from the class Virtual Experimental Activity, to help teachers to provide experimental activities in the classroom to engage concepts that otherwise should only be approached theoretically.
Classroom experimentation – Arduino projects to teach electromagnetism
Authors: Schnider D , Hömöstrei M 
Published: January 2024

Abstract
In this paper, we offer high school physics teachers valuable insights into the effective incorporation of Arduino-based classroom physics measurements for teaching electromagnetics. By engaging students in activities that involve measuring the conductance of liquids and exploring the magnetic field of a solenoid, starting from fundamental concepts and progressing to more complex tasks, we facilitate their journey toward a deeper, abstract understanding of the subject matter. These projects, centered on digital technology, encompass activities such as digital data collection, data analysis, and even functions plotting. These hands-on experiences enhance students’ technical skills, and also provide teachers with a powerful quantitative teaching method, allowing them to emphasize specific physical phenomena and their underlying theoretical principles. Consequently, these Arduino-based measurements play a pivotal role in fostering students’ competence development and improving their attitude towards learning physics.
Using a Mobile Phone as a Measurement Tool for Illuminance in Physics Education
Authors: Vochozka Vladimír 
Published: January 2024

Abstract
Most primary school students in the Czech Republic have a mobile phone. A mobile phone can measure many physical quantities once the appropriate application has been installed. The terms “Light Meter” or “Lux Meter” are names for applications that measure the physical quantity illuminance. At the time of writing, there are more than 50 such applications available on Google Play. These applications utilise data from the ambient light sensor. The study describes the measurement of illuminance using laboratory equipment and mobile phones with installed applications and further explores the reliability of data collected by mobile phones. A comparison was made between data from applications that were in the default settings and calibrated. The values of different applications installed on the same mobile phone were compared, as well as values of the same application installed on different mobile phones. Values were compared at different distances from the light source and at the same distance, but with varying angles. The reaction time for a mobile phone application to detect changes in illumination was measured. Sensitivity to infrared and ultraviolet radiation was also investigated. Seven general conclusions were drawn from all measurements regarding the use of a mobile phone as a luxmeter instead of professional laboratory equipment, provided that the recommendations are followed.