bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of hydroperiod on aquatic food-web structure and energy production in a floodplain wetland: implications for environmental flow management
Authors: Frost Lindsey K. , Mika Sarah J. , Thompson Ross M. , Growns Ivor 
Published: November 2023

Context Environmental water is often used to manage floodplain wetlands that support many taxa, both terrestrial and aquatic. It is important to optimise the managed hydroperiod to maximise the provision of aquatically derived resources from wetlands. Aims To test the hypothesis that increasing hydroperiod affects food-web structure and energy production in floodplain wetlands. Methods Fatty acids and stable isotopes of δ13C and δ15N were used to define food-web structure, and estimate total energy production throughout a managed inundation event in a wetland in the northern Murray–Darling Basin. Key results Food-web complexity increased with an increasing hydroperiod in line with predictable patterns of community assemblage development, before reducing sharply immediately prior to drying. Energy availability increased with an increasing hydroperiod and there was a strong correlation (ρ = 0.669, P = 0.0001) between energy availability and fatty acid concentration, which was in turn related to patterns of taxon occurrence. Conclusions and implications Hydroperiod exerts a strong influence on aquatic invertebrate community trophic dynamics and energy provision. Planned flows should support maturation and stabilisation of the invertebrate community to optimise energy provision to consumers.
Detection of scatterers using an XFEM-BEM level set solver based on the topological derivative
Authors: Canelas Alfredo , Abreu Ana I , Roche Jean R 
Published: November 2023

Abstract
A numerical method is proposed for the solution of the inverse scattering problem. This problem consists of determining the location and shape of an unknown number of inclusions composed by a homogeneous material with known mechanical properties different that those of the surrounding medium. The information available to solve the inverse problem are measurements of the fundamental mechanical magnitude of the wave propagation problem. At the boundary of the scatterers, transmission conditions depending on the material properties are considered. For the solution of the forward problem, a coupled extended finite element method (XFEM)-boundary element method (BEM) is proposed, where the XFEM is used for the bounded region where the scatterers are supposed to be located, and the BEM is used for the exterior domain. The inverse problem is formulated as a topology optimization problem, and solved by means of a heuristic algorithm based on the topological derivative and a level set representation of the scatterers.
Generation of higher-order topological insulators using periodic driving
Authors: Ghosh Arnob Kumar , Nag Tanay , Saha Arijit 
Published: November 2023

Abstract
Topological insulators (TIs) are a new class of materials that resemble ordinary band insulators in terms of a bulk band gap but exhibit protected metallic states on their boundaries. In this modern direction, higher-order TIs (HOTIs) are a new class of TIs in dimensions d > 1. These HOTIs possess

(
d
−
1
)

-dimensional boundaries that, unlike those of conventional TIs, do not conduct via gapless states but are themselves TIs. Precisely, an nth order d-dimensional higher-order TI is characterized by the presence of boundary modes that reside on its

d
c

=
(
d
−
n
)

-dimensional boundary. For instance, a three-dimensional second (third) order TI hosts gapless (localized) modes on the hinges (corners), characterized by

d
c

=
1
(
0
)

. Similarly, a second-order TI (SOTI) in two dimensions only has localized corner states (

d
c

=
0

). These higher-order phases are protected by various crystalline as well as discrete symmetries. The non-equilibrium tunability of the topological phase has been a major academic challenge where periodic Floquet drive provides us golden opportunity to overcome that barrier. Here, we discuss different periodic driving protocols to generate Floquet HOTIs while starting from a non-topological or first-order topological phase. Furthermore, we emphasize that one can generate the dynamical anomalous π-modes along with the concomitant 0-modes. The former can be realized only in a dynamical setup. We exemplify the Floquet higher-order topological modes in two and three dimensions in a systematic way. Especially, in two dimensions, we demonstrate a Floquet SOTI (FSOTI) hosting 0- and π corner modes. Whereas a three-dimensional FSOTI and Floquet third-order TI manifest one- and zero-dimensional hinge and corner modes, respectively.
Characterizing the fault performance of real-time precise satellite orbit and clock correction products
Authors: Huang Weiquan , Li Menghao , Li Liang , Wang Renlong , Wang Liuqi , Wang Ningbo 
Published: November 2023

Abstract
The a priori fault probability of the real-time precise satellite orbit and clock correction products is the critical parameter for integrity monitoring of precise point positioning (PPP). The traditional fault probability evaluation methods use the worst-case instantaneous user ranging error (IURE) as the conservative test statistic. However, the systematic biases of IURE contained in the worst-case IURE barely affect the PPP accuracy, which will undermine the statistical distribution of test statistic and reduce the sensitivity of fault detection. The fault probability will be estimated over-conservatively for the traditional methods. By clarifying the sources of the systematic biases, a new test statistic is constructed by deliberately removing the systematic biases of IURE originated from satellite orbit and clock errors. One-year Global Positioning System correction products evaluation results have demonstrated that the constructed test statistic follows the Gaussian distribution with the decreased uncertainty and the improved fault detection sensitivity. The real-world data experiments have shown that the a priori probabilities of the satellite fault and the constellation fault are at the order of 10−4 and 10−5 levels, respectively.
Model for predicting the angles of upper limb joints in combination with sEMG and posture capture
Authors: Wang Zhen-Yu , Xiang Ze-Rui , Zhi Jin-Yi , Ding Tie-Cheng , Zou Rui , Lan Yong-Xia 
Published: November 2023

Abstract
Since poor man–machine interaction and insufficient coupling occur in the processes of angle prediction and rehabilitation training based purely on the surface electromyography (sEMG) signal, a model for predicting the angles of upper limb joints was presented and validated by experiments. The sEMG and posture capture features were combined to build a hybrid vector, and the intentions of upper limb movements were characterized. The original signals were pre-treated with debiasing, filtering, and noise reduction, and then they were integrated to obtain signal characteristics. Then, feature values in the time domain, frequency domain, time-frequency domain, and entropy were extracted from the treated signals. The snake optimizer least squares support vector machine (SO-LSSVM) was modeled to predict the angles of upper limb joints to improve the poor precision and slow velocity of existing models in the movement control field. Experimental results showed that the prediction model performed well in predicting the motion trails of human upper limb joints from the sEMG signal and attitude information. It effectively reduced both skewing and error in prediction. Hence, it holds great promise for improving the man–machine coupling precision and velocity. Compared to the conventional LSSVM model, the proposed SO-LSSVM model reduced the training time, execution time, and root mean square error of evaluation parameters by 65%, 11%, and 76%, respectively. In summary, the proposed SO-LSSVM model satisfied the real-time requirement for rehabilitation robots and showed high accuracy and robustness.
A whale optimization detection (WOD) method for bladder volume estimation with bioelectrical impedance spectroscopy (BIS)
Authors: Hong Zhiyang , Zhu Jin , Wu Yang , Fang Junyang , Ye Ming , Liu Kai , Yao Jiafeng 
Published: November 2023

Abstract
A whale optimization detection (WOD) method is presented for rapid bladder volume estimation with bioelectrical impedance spectroscopy (BIS). Firstly, the WOD method for bladder volume estimation is established, which includes a bladder volume estimation electrical equivalent circuit (EEC) model and a rapid fitting strategy. Secondly, an abdominal phantom is constructed, which consists of an abdominal cavity shell and four bladders with volumes of V
b = 30 ml, 100 ml, 200 ml, and 300 ml. Next, BIS experiments are conducted using the phantom with the WOD method fitted to the obtained data. The results demonstrated a high linear correlation coefficient R
2 > 0.987 between the experimental and WOD results. Finally, in vivo testing is performed using both the Caresono HD-5 ultrasonic bladder scanner and the proposed WOD method. The EEC parameters obtained by the WOD method form a mathematical formula that accurately describes the subject’s bladder volume, with a detection correlation coefficient r = 98.71%, and the maximum relative error δ = 5.88% between WOD and ultrasound testing results. In conclusion, the proposed method is expected to be applied for rapid monitoring of patients’ bladder volume.
RLC series circuit made simple and portable with smartphones
Authors: Torriente-García Ives , Martí Arturo C , Monteiro Martín , Stari Cecilia , Castro-Palacio Juan C , Monsoriu Juan A 
Published: November 2023

Abstract
This article presents a novel method for studying RLC series circuits using two smartphones, one used as a signal generator and the other as an oscilloscope. We measure the voltage at the external resistor as a function of frequency when subjected to a sinusoidal electromotive force. The experimental results demonstrate a remarkable agreement with the theoretical curve for the voltage at the resistor and the resonance frequency, validating the accuracy of the smartphone-based setup. The experiment fills the gap in educational materials related to electrical circuits and provides a portable alternative to traditional, expensive laboratory equipment.
Effect of problem-based learning on students’ problem-solving ability to learn physics
Authors: Gumisirizah Nicholus , Muwonge Charles M , Nzabahimana Joseph 
Published: November 2023

Abstract
A learner’s success is supported by the ability to understand real-world problems. This study aimed to examine the effect of problem-based learning on problem-solving ability in the teaching and learning of physics. The study was guided by socio-constructivism theory. A quasi-experiment was conducted with 829 Senior-2 Physics students (age 13–15) from eight (8) selected lower secondary schools in Sheema District, Uganda. Schools were assigned to treatment and control groups using a purposive random sampling technique. Students’ problem-solving ability was measured by conducting a problem-solving ability test in each group before and after studying a chapter on simple machines in physics. Repeated measures analysis of variances was applied for data analysis. The study’s findings showed a significant improvement in students’ problem-solving ability with simple machines in the treatment group compared to the control group (p < .001). Therefore, educators are encouraged to embrace learner-centred methods that enhance students’ problem-solving abilities to help them compete in the world of work.
Hybrid optimization of laser-driven fusion targets and laser profiles
Authors: Li Z , Zhao Z Q , Yang X H , Zhang G B , Ma Y Y , Xu H , Wu F Y , Shao F Q , Zhang J 
Published: November 2023

Abstract
Quasi-isentropic compression is an effective method to achieve high-density and high-temperature implosion in laser-driven inertial confinement fusion (ICF). However, it requires precise matching between the laser profile and the target structure. Designing the optimal laser profile and the corresponding target for ICF is a challenge due to the large number of parameters involved. In this paper, we present a novel method that combines random walk and Bayesian optimization. The basic sampling data for Bayesian optimization are a series of laser pulse profiles and target structures that can produce relatively high areal densities obtained by the random walk method. This approach reduces the number of samples required for Bayesian optimization and mitigates low efficiency in the latter stages of the random walk method. The method also reduces the randomness in the optimization process and enhances the optimization efficiency. It should have important applications in ICF research.
The ternary phase diagram of nitrogen doped lutetium hydrides can not explain its claimed high Tc superconductivity
Authors: Gubler Moritz , Krummenacher Marco , Finkler Jonas A , Flores-Livas José A , Goedecker Stefan 
Published: November 2023

Abstract
This paper presents the results of an extensive structural search of ternary solids containing lutetium, nitrogen and hydrogen. Based on thousands of thermodynamically stable structures the convex hull of the formation enthalpies is constructed. To obtain the correct energetic ordering, the highly accurate RSCAN DFT functional is used in high quality all-electron calculations, eliminating possible pseudopotential errors. In this way, a novel lutetium hydride structure (HLu2) is found that is on the convex hull. An electron phonon analysis however shows that it is not a candidate structure for near ambient superconductivity. Besides this structure, which appears to have been missed in previous searches, possibly due to different DFT methodologies, our results agree closely with the results of previously published structure search efforts. This shows, that the field of crystal structure prediction has matured to a state where independent methodologies produce consistent and reproducible results, underlining the trustworthiness of modern crystal structure predictions. Hence it is quite unlikely that a structure, that would give rise within standard BCS theory to the superconducting properties, claimed to have been observed by Dasenbrock-Gammon et al (2023 Nature
615 244), exists. This solidifies the evidence that structures with high Tc conventional superconductivity, that could give rise to the experimental claims, do not exist in this material.
A Bayesian quantum state tomography along with adaptive frameworks based on linear minimum mean square error criterion
Authors: Mondal Subhadeep , Dutta Amit Kumar 
Published: November 2023

AbstractQuantum state tomography (QST) is essential for characterizing unknown quantum states. Several methods of estimating quantum states already exist and can be classified mainly into three broad classes. They are based on the criteria like maximum likelihood, linear inversion, and Bayesian framework. The Bayesian framework for QST gives a better reconstruction performance. However, the existing methods of the Bayesian frameworks are computationally extensive and, most of the time require knowledge about the prior distribution of the quantum state. In this paper, we propose a Bayesian method of QST based on the linear minimum mean square error criterion, where the prior statistics are estimated and the computational complexity is comparable to that of the linear inversion based QST method. We also propose an adaptive version based on the block estimation of parameters. Extensive numerical simulations are conducted to demonstrate its efficacy over the linear inversion-based QST regarding trace distance error metric.
Effect of annealing temperature on the formation of oxygen vacancies on the surface of flower-like SnSe/SnO2 heterostructure and visible light catalytic performance
Authors: Liao Lei , Li Siyuan , Jin Yingrong , Cai Fanggong , Zhang Qinyong 
Published: November 2023

Abstract
The morphology, structure, and oxygen vacancies in principle determine the light absorption, charge transfer, and separation of photocatalysts, thereby determining their photocatalytic performance. In this study, flower-like SnSe obtained from hydrothermal reactions was oxidized to obtain heterojunctions with SnSe/SnO2. Flower-like SnSe/SnO2 heterojunctions with different concentrations of oxygen vacancies were prepared by annealing them in an argon atmosphere at different temperatures. The flower-like SnSe/SnO2 series with different oxygen vacancies were systematically characterized by TEM, XRD, XPS, PL, and EPR. The research results demonstrate the presence of oxygen vacancies in the flower-like SnSe/SnO2. As the annealing temperature increases, the surface oxygen vacancy concentration shows a trend of first increasing and then decreasing. When the annealing temperature reaches 600 °C, the oxygen vacancy concentration of flower-like SnSe/SnO2 is the highest. Meanwhile, research has shown that surface oxygen vacancies help expand the light absorption range, and the increased valence bandwidth leads to effective charge transfer and separation, thereby promoting visible light photoactivity. SnSe/SnO2-600 °C exhibited excellent visible light photocatalytic activity. The photodegradation of methylene blue (MB) at ≥ 400 nm can reach ∼70% within 120 min. This study verified the route for the introduction of oxygen vacancies via facile calcination and constructed SnSe/SnO2 with surface oxygen vacancies, providing a reference with deep insights for improving photocatalytic activity.
Particle dynamics, black hole shadow and weak gravitational lensing in the f (Q) theory of gravity
Authors: Ditta Allah , Tiecheng Xia , Atamurotov Farruh , Hussain Ibrar , Mustafa G 
Published: November 2023

Abstract
We study the particle dynamics around a black hole (BH) in f(Q) gravity. First, we investigate the influence of the parameters of f(Q) gravity on the horizon structure of the BH, photon orbits and the radius of the innermost stable circular orbit (ISCO) of massive particles. We further study the effects of the parameters of f(Q) gravity on the shadow cast by the BH. Moreover, we consider weak gravitational lensing using the general method, where we also explore the deflection angle of light rays around the BH in f(Q) gravity in uniform and nonuniform plasma mediums.
Computing character tables of symmetric groups using higher order permutation representations
Authors: Lei Zikang 
Published: November 2023

Abstract
In this paper, we will introduce the topic of representation theory by focusing on the techniques of computing character tables of finite groups, in particular, the symmetric group Sn
. First, we will introduce some basic concepts of representation theory of finite groups over ℂ. Then we will compute the character tables for S
3 and S
4 using the classical methods introduced in Section 2. Also, we will construct a series of representations for Sn
and compute their characters. Finally, we will compute the character tables for S
5 and S
6 using our method introduced in Section 3.
Convex optimization and the smallest ball problem
Authors: Yang Junchi 
Published: November 2023

Abstract
The Smallest Ball Problem is a famous problem in mathematics that was proposed by James Joseph Sylvester. In the past, many algorithms to solve this problem were founded but there was only a limited number of researches that focused on the rigorous mathematical proof of this problem. Thus, the goal of this essay is to provide a rigorous proof of the claim that the smallest enclosing ball must exist and it is unique. In this essay, the Smallest Ball Problem will be converted into a convex optimization problem and the result that the smallest enclosing ball exists and is unique can be proved by proving the optimal solution of this programming problem exists. The meaning of this research is to give a theoretically mathematical proof of the Smallest Ball Problem so that it can tell the algorithms to solve this problem can always work. Thus, it can also ensure the effectiveness of all the related algorithms.
A study on aerodynamics of Ultra-efficient cars
Authors: Zhang Boxiang 
Published: November 2023

Abstract
Ultra-efficient cars (i.e. Formula One racing cars) are loaded with many different aerodynamic components. They interact to produce highly nonlinear flows, which have a very complex effect on the airflow around the racing car. Clearing up fluid phenomena makes it possible to optimize aerodynamic components effectively. This paper reviews the aerodynamic performance of currently used shapes, as well as the definition of the design constraints for the vehicle. The designs are inspired by formula one cars, especially by Honda F1 Team, but they are adjusted according to the limit conditions of CFD simulation software Ansys CFX, and parameters are scaled accordingly based on the space requirements of this test. A level of velocity at 40 km/h is tested, giving ideas of the full model performance. Results are then compared and discussed to obtain a comprehensive and valid conclusion about the potential improvement in the aerodynamics of road cars, which can be extracted from those ultra-efficient ones.
Research of the problems of heat conduction in fluids
Authors: Wang Haojun 
Published: November 2023

Abstract
In the fluid of the pipeline, the phenomena of heat convection, heat conduction, and radiation heat transfer occur between the pipeline and the outside world as well as between the pipeline and the inside. In the calculation of the relevant temperature and heat, we need to know the heat transfer coefficient, pipeline characteristic length, flow velocity, and other data to get the results. Based on previous research results, this paper will use Ansys software to explore the change law of heat transfer effect with various parameters. We can find that in the simulation, as the flow rate increases, the heating effect will become worse and worse.
Design and analysis of root locus based controllers
Authors: Yang Wenbo 
Published: November 2023

Abstract
The root locus method is the classical method for analyzing the variation of the position of the poles of a closed-loop control system transfer function in the complex plane. It is also the basis for guiding the design of various controllers. Starting from the nature of the root locus, this paper takes a standard form of closed-loop feedback control system as an example, and analyzes in detail the internal logic of designing a controller and compensator by the root locus method. At the same time, software such as MATLAB/Simulink, and Octave are used. The working principles and properties of the PD controller; the lead and lag compensator, their interconnections, advantages, and characteristics, as well as the adjustment of parameters to better suit practical needs, are sorted out. The PD controller improves the system response, the lead compensator eliminates the PD controller’s defects, and the lag compensator reduces the steady-state error of the system. It provides help for understanding the essence of controller design and provides design ideas for control problems in actual engineering.
Effect of slab dimensions on the maximum stress and ultimate vertical load of a 15-story flat slab building
Authors: Wang Tingyu 
Published: November 2023

Abstract
The research of flat slab structures requires more investigation into the full-scale analysis of steel flat slab structures under vertical loads. The impact of slab dimensions on the maximum stress of slabs and columns, as well as the ultimate vertical load at the linear elastic stage, has been examined using full-scale finite element models. The particular structures selected for the analysis are 15-story steel flat slab structures with various slab dimensions under the static vertical load and standard earth gravity. This research also involves: (1) the verification of stress singularity at the corner of cubic columns in the finite element model; (2) the discussion about the variation of maximum stress of slabs and columns as the floor changes, and the interaction of columns and slabs; (3) the validation of the vulnerability of slab-column connection.