bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suppression of parasitic lasing in erbium doped thin film lithium niobate waveguide amplifier by integrated wavelength division multiplexer
Authors: Han Jinli , Li Mengqi , Dong Qiaonan , Wu Rongbo , Wang Zhe , Liu Zhaoxiang , Sun Saisai , Fang Zhiwei , Wang Min , Zhang Haisu , Cheng Ya 
Published: December 2024

Photonic integrated circuits based erbium doped amplifiers have attracted great interest due to their compact footprint, high gain in the telecom C-band, and high scalability for functional integration. In this work, a wavelength division multiplexer integrated erbium doped waveguide amplifier fabricated on the thin film lithium niobate on insulator platform is demonstrated. An on-chip saturated power of 10 dBm with the net gain around 10 dB is achieved from the monolithically integrated amplifier chip with the footprint of only 3 × 5 mm2. In particular, the suppression of parasitic lasing in the waveguide amplifier is realized thanks to the spectral response of the integrated wavelength division multiplexer. Theoretical analysis of parasitic lasing on amplifier performance is also conducted. The demonstrated integrated erbium doped waveguide amplifier will find great use in various applications based on the thin film lithium niobate on an insulator platform.
Enhanced catalytic degradation of methylene blue using self-propelled Janus micromotors: An insight into decomposing characteristics of passive and active hematite particles studded with Pt nanoparticles
Authors: Khan Faizan , Pawak Vishal Singh , Dugyala Venkateshwar Rao , Mondal Tarak , Sabapathy Manigandan 
Published: December 2024

Recent advancements in catalytic micromotors have shown significant potential for environmental applications, yet challenges such as particle agglomeration persist. In this study, we compare the degradation of methylene blue using hematite particles fully coated with platinum and those partially decorated with platinum. The selective decoration, confirmed through techniques like EDX, FESEM, TEM, and XPS, plays a crucial role in the micromotors’ behavior. The decomposition of hydrogen peroxide (H2O2) by Pt nanoparticles on one side of the hematite particles generates thrust, propelling the micromotors and enhancing their interaction with pollutant molecules. This active mobility helps counteract agglomeration, preventing the formation of irregular 3D clusters and improving catalytic efficiency. Our findings show that partially decorated particles achieve up to 85% dye removal within 90 min, outperforming fully decorated particles, which reach only 33% efficiency due to aggregation and sedimentation. These results underscore the importance of optimized surface decoration for improving the performance and stability of catalytic systems in pollutant degradation.
Amplitude stability research and experimental investigation of the actuation circuit of the inertial sensor for space gravitational wave detection
Authors: Zhang Jiawei , Yu Peilong , Lin Shuyang , Ma Qinbo , Han Zhe , Huang Jianping 
Published: December 2024

Abstract
The primary measure of scientific performance for inertial sensors used in space gravitational wave detection is the residual acceleration noise of the test mass (TM). This residual noise arises from both the internal circuit and the external environment. The actuation circuit, a crucial component of the internal circuit, significantly affects the TM’s residual acceleration noise through its amplitude stability, thereby impacting the scientific performance of the inertial sensor. In this study, we designed the actuation circuit for an inertial sensor, developed a mathematical model to describe its amplitude stability, and experimentally verified the model’s accuracy. Experimental results demonstrate that the current design enables the actuation circuit to achieve an amplitude stability of 3.6 ppm Hz−1/2 at 1 mHz, thereby offering theoretical support for achieving a higher amplitude stability in the millihertz frequency band.
Electrically controlled flexible and varifocal microlens array using liquid crystals on polymer
Authors: Panchal Rahul , Sinha Aloka 
Published: December 2024

Abstract
Microlens arrays (MLA) on flexible substrates have a wide range of applications in advancing curved integral imaging and three-dimensional (3D) display systems with a large field of view. We developed an electrically controlled varifocal MLA on flexible polyethylene terephthalate (PET) substrates by infiltrating liquid crystals (LC) in polymeric concave lenses. The focusing and imaging characteristics of the flexible LC-MLA are studied experimentally. When voltage is applied across the LC layer, the refractive index of the LC changes, which causes a change in the effective focal length of the MLA. The electrically tunable focal length and tunable focusing of the MLA are experimentally demonstrated. The mathematical analysis of the LC MLA is performed using the MATLAB platform. The presented flexible LC-MLA is developed using simple and cost-effective fabrication methods, which can potentially be used in future 3D displays and imaging solutions.
Vision-based weld detection and localization for climbing robots in large-scale storage tank inspections
Authors: Wang Ruifeng , Ma Nvjie , Xu Zhihao , Zhou Xuefeng , Pan Jia , Gu Shichao 
Published: December 2024

Abstract
Climbing robots are considered an effective solution for inspecting welds on the walls of large storage tanks. For these robotic systems, the efficient and accurate identification and localizing of weld seams are crucial prerequisites for ensuring precise weld seam tracking. In this paper, we investigate machine vision-based algorithms for feature recognition and localization of weld seams on tank walls for inspection of weld seams by a climbing robot. First, we designed the model of the image algorithm to extract the weld features of the tank walls. After extracting the weld features, we propose the novel idea of feature discretization and a Min-outer Rectangle Fitting Algorithm (MRFA), which will achieve the fitting of rectangular features on the discretized weld features. We constructed a mathematical model for calculating the orientation angle of the rectangular box based on the extracted rectangular boxes. This model allows for the real-time and efficient extraction of the rectangular feature’s pose information (x, y, θ). We also propose an efficient method for calculating the curvature of a curve trajectory. The experimental results demonstrate that the proposed image algorithm model and MRFA effectively identify weld features on the storage tank wall surface, while simultaneously achieving high-accuracy feature localization. Positioning errors are maintained within 3 mm for position and 3 degrees for azimuth, indicating both high precision and robustness. Additionally, the algorithm processes each image in approximately 80 milliseconds. The lightweight and efficient design of the proposed model allows it to be easily deployed on a climbing robot for weld seam detection and tracking on tank walls.
Design and control of radial electromagnetic bearing for flywheel battery
Authors: Sun Binbin , Meng Fantao , Wang Pengwei , Cheng Shuo , Feng Chao 
Published: December 2024

Abstract
The increase in rotational speed is the key to enhancing the energy storage capacity of flywheel batteries. Non-contact bearings can ensure reliable operation of high-speed flywheel batteries. To design electromagnetic bearings that meet the requirements of high-speed flywheel batteries. Firstly, a multi parameter and multi-objective optimization model for the radial electromagnetic bearing structure was designed with the optimization objectives of maximum electromagnetic force and minimum volume. On the basis of ensuring maximum electromagnetic force, the minimum spatial volume is reduced by 16.58%. Furthermore, the influence of bias current and control current on the electromagnetic force and rotor displacement of radial electromagnetic bearings was analyzed. The bias current and control current that satisfy the current stiffness and displacement stiffness were determined. Then, a mathematical model for differential control of radial magnetic bearings was constructed and a magnetic bearing controller based on adaptive discrete sliding mode control was designed. Finally, flywheel battery bench testing and data analysis were conducted. The results show that the designed radial magnetic bearing can achieve low response error, low system oscillation, and high robustness operation under the conditions of buoyancy step, foundation excitation, and random excitation. Compared with the sliding mode control method, the maximum difference in displacement tracking error was reduced by 62.31%, the average error was reduced by 42.74%, and the energy consumption was reduced by 49.32% under random excitation test conditions.
Nonradial symmetry and blow-up of ground states for a Schrödinger–Poisson system with logarithmic term
Authors: Wang Zhengping , Zeng Xiaoyu , Zhou Huan-Song 
Published: December 2024

Abstract
We consider the following Schrödinger–Poisson system

{

−
Δ
u
+
V

(
x
)

u
+
λ
ϕ

(
x
)

u
=
u
log

u
2

,

x
∈

ℝ
3

,

(0.1)

−
Δ
ϕ
=

u
2

,

lim

|
x
|
→
+
∞

ϕ

(
x
)

=
0
,

where

λ
∈

R

is a parameter,

V
∈
C
(

R

3

,

R

+

)

is a coercive potential. We prove that, if

V
(
x
)
∼
(
log
⁡

|

x

|

)

1
2

at infinity, then the energy functional I

λ
associated with (0.1) fails to be C
1, and there is

λ
0

>
0

such that (0.1) has a ground state

u
λ
0

for any

λ
∈
(
0
,

λ
0

)

, which blows up as

λ
→

0
+

, but if

V
(
x
)
=
V
(

|

x

|

)
∼
(
log
⁡

|

x

|

)

α

with

α
∈
(
0
,
1
)

at infinity, then there exists a sequence

λ
n

→

0
+

such that each

u

λ
n

0

must be non-radially symmetric. However, if V(x) grows like

|
x

|
γ

(γ > 0) at infinity, we show that the functional I

λ
is of C
1 and (0.1) has a ground state

u
λ
1

for each λ < 0 which is radially symmetric. Also, the limit behavior of

u
λ
1

as

λ
→

0

−

is discussed.
Multi-resonant TVA formed by a tree of deflated composite beams with core structured fabrics
Authors: Gardonio Paolo , Ortis Lisa , Rustighi Emiliano , Malacarne Ciro , Perini Matteo 
Published: December 2024

Abstract
This paper presents a study on a multi-resonant tuneable vibration absorber for the control of flexural vibrations of thin structures in a low frequency band where the response is characterized by distinct lightly damped resonances of low order flexural modes. The absorber is formed by a tree of deflated composite beams made by a core structured fabric wrapped on a plastic skin. The beams have increasingly smaller length and are fixed in the middle on a mast that works as a base-post and vacuum-junction too. The fabric in each beam is made by a lattice of interlocked truss-like rigid particles. The uniform pressure exerted by the deflated skin forces the particles to jam such that the fabric moves from its natural fluid-like state to a solid state whose rigidity depends on the confining pressure exerted by the skin. Hence, each beam is characterized by a fundamental flapping vibration mode whose response resembles that of a classical mass-spring-damper vibration absorber and can be suitably tuned by adjusting the level of vacuum. The paper first analyses the working principles of single-beam and three-beams absorbers with respect to their vibration transmissibility and base impedance frequency response functions. Then, it presents the vibration control generated by the single-beam and the three-beams absorbers tuned to minimise the resonant responses of a single or three low order flexural modes of a thin plate. The paper shows that the operational frequency of each beam-absorber can be suitably adapted in a band of 8 Hz by varying the vacuum pressure in a 5–80 kPa range. Also, it shows that the single-beam or multi-beams absorbers reduce the resonant response of the target flexural modes by 10–20 dB.
Dependence of water radiation on temperature at microwaves
Authors: Gavrilin S N 
Published: December 2024

Abstract
Extra experimental and calculated data are presented for the previously published work. The dependence of water thermal radiation from the water temperature was studied. The experiment was performed outdoors. A radiometer with central frequency 37,5 GHz (8 mm) was used. The increase of brightness temperature was 3 K in the water temperature range 30 °C–50 °C and about 25 K in the temperature range 55 °C–85 °C. The radio emission of water depends non-linearly on the kinetic temperature. It was measured that the radio brightness of the surface temperature increases from 0.28 to 1 K per 1 °C of water heating. The discrepancy between theoretical estimates and experimental data is noted. An explanation of the reasons for this discrepancy is offered.
Lattice Boltzmann method to simulate photocatalytic reduction of CO2 over PCN-601 coated on transparent porous substrate
Authors: Li Nannan , Zhan Hongwei , Tong Kai , Chen Zhidong , Kong Yanqiang , Yang Lijun , Du Xiaoze 
Published: December 2024

Abstract
Photocatalysis offers a promising approach to convert solar energy and CO2 into clean chemical energy, such as methane (CH4) and carbon monoxide (CO), contributing to carbon neutrality. This study proposes a lattice Boltzmann method to solve radiation transport within transparent porous substrates for photocatalytic CO2 reduction. Numerical simulations of mass transfer, radiation, and reaction kinetics are in good agreement with experimental results. The influence of triply periodic minimal surfaces (TPMS) as porous substrates on photocatalytic efficiency is investigated, identifying substrate thickness as the dominant variable affecting performance. At reduced thicknesses, porosity and surface area gain importance by enhancing light absorption and fluid flow. Notably, at 10 pores per inch (PPI), a 2 mm thick Schwarz D substrate demonstrates comparable photocatalytic performance to a 7 mm thick gyroid. However, at 30 PPI, it leads to diminished performance despite similar porosity by reducing thickness. These results suggest that a PPI value around 10 optimizes the efficiency for photocatalytic CO2 reduction.
Dispersive and attenuation behavior of Love wave in a non-local highly heterogeneous media with imperfect contact condition
Authors: Sadab Mohd , Kundu Santimoy 
Published: December 2024

Abstract
The primary aim of this study is to explore the impact of different physical parameters on the propagation of Love waves in non-local media. This study considers heterogeneous orthotropic viscoelastic properties within a layer and the variation of sandy medium properties with exponential depth, representing the half-space. Furthermore, the interface between the layer and the half-space is considered mechanically imperfect and perfect. The solutions of mechanical displacement of the layer and half-space are derived separately by solving the second-order hyperbolic type differential equation with the help of a variable-separable technique. A closed form of the dispersion relation is obtained using appropriate boundary conditions involving the medium’s non-local elasticity and inhomogeneity parameters. Verification of the dispersion relation is shown by deriving some particular cases and comparing them with the classical dispersion relation of Love wave. The effects of physical parameters (like viscoelasticity, inhomogeneity, interfacial imperfection, sandy, non-locality, and thickness of the layer) on the phase and attenuation phenomena of Love wave are investigated through numerical calculations and graphical representation. Furthermore, it is observed that the particle displacement in the layer decreases with depth, while in the half-space, the amplitude decreases oscillatory with depth, and the displacement gradually converges towards zero. A comparative graphical analysis of these parameters on the phase and attenuation characteristics of Love wave through the stratified Earth’s structure with imperfect and perfect interfaces has been accomplished.
Recent progress and development trends of oil wear particle detection sensors applied in marine machinery condition monitoring
Authors: Zhang Hongpeng , Han Wenbo , Bai Chenzhao , Li Wei , Wang Xin , Liu Yu 
Published: December 2024

Abstract
Oil wear particle can offer wear condition for marine machinery. The shape, size and composition of wear particle can supply important information for diagnosing the type and severity of marine machinery faults. Through oil wear particle detection, potential marine machinery fault diagnosis can be found early, thereby reducing the risk of marine machinery failure diagnosis and improving the reliability and service life of marine machinery. This review summarizes the detection methods, technical characteristics and research progress of oil wear particle detection sensors applied in marine machinery condition monitoring. Oil wear particle detection sensors are divided into impedance-based particle detection method and non-impedance-based particle detection method. Impedance-based method includes inductance, capacitance and resistance principles. Non-impedance-based method includes image processing, optical and acoustic principles. Finally, it points out the future development trends and novel ideas for the oil wear particle detection sensors employed in marine machinery.
On the singular position-dependent mass
Authors: Lima F C E , Belchior F M , Almeida C A S 
Published: December 2024

Abstract
Revisiting the issue associated with Position-Dependent Mass (PDM), we reaffirm that the appropriate framework for addressing a generic PDM is the symmetrization proposed by BenDaniel and Duke. To accomplish this result adopts the effective mass Hamiltonian proposed by von Roos, corrected by a symmetrized kinematic term. After verifying the appropriate ordering to approach the PDM issue, one investigates a crystalline lattice with a defect described by a singular PDM. The singular mass profile proves intriguing as it yields an atom’s cluster in the neighborhood of the singularity. Considering that a restoring force acts on the atoms, one notes that the confluent Heun function describes the quantum states. Furthermore, one highlights that when the effective mass distribution tends to a constant profile, we recover a system similar to the harmonic oscillator.
Tuning planar transverse domain wall dynamics in bilayer nanostructures using transverse magnetic fields, Rashba, and spin-Hall effects
Authors: Halder Ambalika , Maity Sumit , Dwivedi Sharad 
Published: December 2024

Abstract
This work deals with the tunability of a planar transverse domain wall with an arbitrary azimuthal angle, achieved by applying a transverse magnetic field of tunable strength and fixed orientation. To be precise, we investigate the static and dynamic features of a planar transverse domain wall within a bilayer nanostructure consisting of a ferromagnetic layer and a non-magnetic heavy metal layer, employing the Landau–Lifshitz-Gilbert equation as our theoretical framework. The domain wall dynamics are analyzed through the collective coordinate method and regular perturbation asymptotic approach, accounting for the combined effects of axial and transverse magnetic fields, spin-polarized electric currents, Rashba effect, and spin-Hall effect. Our study comprehensively analyses the planar transverse domain wall profile, characterized by sharply defined boundaries between adjacent domains and a precise distribution of the transverse magnetic field. In addition, we detail the linear polar angle distribution within the domain wall region, the capability to freely tune the domain wall width, and the enhanced domain wall velocity in steady-state regime. The analytical results are further numerically illustrated, offering valuable insights into manipulating and controlling domain wall dynamics.
Spin glass behavior of single-crystalline ErFe2O4−δ
Authors: Sihui Li , Konishi Shinya , Tanaka Katsuhisa 
Published: December 2024

Abstract
We investigated magnetic properties of ErFe2O4–δ
single crystal containing oxygen vacancies with value of δ being estimated to be 0.066. The temperature dependence of dc magnetization in zero field cooling (ZFC) process reveals that ErFe2O4–δ
undergoes a ferrimagnetic transition at 234 K followed by a broad peak at 224.3 K. The latter is attributable to the spin glass transition as indicated by the strong frequency dependence of temperature-dependent ac susceptibility. The frequency variation of transition temperature is described well by the dynamic scaling law and the critical exponent is similar to those reported for typical spin glasses. Additionally, the spin glass transition at 224.3 K is confirmed by the fact that the magnetic field dependence of irreversible transition temperature is coincident with the de Almeida-Thouless line and that the aging memory and rejuvenation effect is observed. Noticeably, ErFe2O4−δ
single crystal exhibits the field-cooled hysteresis loop shift and training effect below 200 K, suggesting the occurrence of exchange bias effect originating from the spin glass phase.
Numerical study of minority ion heating scenarios in CN-H1 stellarator plasma
Authors: Wang Shuangshuang , Yin Lan , Chen You , Gong Xueyu , Peng Yaoyi , Zheng Pingwei , Ma Wankun , Ou Qi 
Published: December 2024

Abstract
A preliminary simulation of ion cyclotron resonance heating (ICRH) in the poloidal cross-section at the antenna location of the CN-H1 (Chinese Heliac 1) stellarator has been conducted for the first time using the full-wave solver TORIC. The heating scheme employed focuses on minority ion heating of He4 (H), with an independent investigation into the effects of wave frequency, toroidal mode number, and minority ion concentration on ICRH. Preliminary simulation results indicate that, under the conditions of wave frequency f = 4.7MHz, central magnetic field B
0 = 0.32T and low-temperature, low-density plasma (with density on the order of 1018 m−3 and temperature in the range of tens of eV), more efficient minority-ion heating can be achieved when the toroidal mode number is in the range of 10–20 and the minority ion concentration is between 15% and 30%. This simulation provides theoretical insights and delineates the parameter space for prospective ICRH experiments in CN-H1.
An analytical model for dispersion relation of parallel plate Waveguide with periodic metallic cylinder nails
Authors: Mai Huanxiao , Liu Xiaobo 
Published: December 2024

Abstract
In this letter, a novel analytical model for a parallel plate waveguide composed of periodic metallic cylinder nails is developped, which is especially effective for sparse nails at higher frequencies. Based on the proposed model, one can effectively and precisely derive the dispersion relation of parallel plate Waveguide with the periodic metallic cylinder nails.The waveguide is modeled as a transmission line with periodically loaded parallel impedances. These impedances correspond to the periodic metallic cylinder nails arranged in a plane perpendicular to the propagation direction. To solve for the parallel impedance, the mirror principle is employed to extend the periodic metallic cylinder nails into the full space. Subsequently, based on the current distribution on the metallic nails, Fourier transformation and Poisson summation techniques are utilized to express the radiated field in terms of multiple Floquet modes. The boundary condition for the metallic nails is then applied to derive the analytical expression for the parallel impedance. Simulation results strongly support the proposed theory. Notably, the transmission line theory stipulates that the zero-order free mode, or TEM wave, should dominate the waveguide with minimal high-order coupling along the propagation direction.Compared to existing methods that treat dense nails as three-dimensional homogenized materials, this study is more applicable to scenarios involving relatively sparse nails at higher frequencies.