bluuebunny/crossref_metadata_2025 huggingface dataset:
Addressing the carbon and nitrogen impurity screening issue on HL-2M snowflake minus and conventional divertor using SOLPS
Authors: Zhou Yue , Zheng Guoyao , Du Hailong , Li Jiaxian , Pan Wei , Xue Lei , Xue Miao , Wang Shuo
Published: March 2023

This paper demonstrates the benefits of the HL-2M SF (snowflake) minus divertor on power exhaust and impurity screening compared with the LSN (lower single null) conventional divertor using SOLPS 5.0 code package. In order to estimate the effectiveness of the impurity screening capability in the HL-2M SF minus divertor, we analyze the impurity transport behavior with intrinsic carbon impurities (P
sol = 4 MW) and external injected nitrogen impurities (P
sol = 6 MW) in the LSN and SF minus divertors. The simulation results reveal that an input power of

4

MW

and electron density of

2.5
×

10

19

m

−
3

on the outer mid-plane can induce a nearly 80% pressure drop in the SOL (scrape-off layer) flux tube, representing the transition of the detachment regime in the SF minus divertor. For the higher power operation with P
sol = 6 MW, a nitrogen gas puffing rate at

3
×

10

20

s

−
1

is sufficient to exhaust excessive energy and facilitate detachment in the SF minus divertor. However, a higher gas puffing rate is necessary for the LSN divertor, indicating an improved power exhaust capability in the SF minus divertor. Furthermore, the maximum effective charge (

Z

eff

) in the SF minus divertor SOL region is nearly 1.45 versus 3.5 in the LSN case with P
sol = 4 MW. The maximum

Z

eff

in the SF minus divertor SOL region is below 2.4, versus 5.5 in the LSN case with the same impurity gas puffing rate when

P

sol

=
6

 MW

. Moreover, the impurity ions accumulate in the divertor region in the SF minus case, which demonstrates the effectiveness of the impurity screening capability in the HL-2M SF minus divertor. We find that the higher ionized state impurity ions contribute to the increase of

Z

eff

and determine the impurity level upstream. On the one hand, the detached divertor regime has the benefit of suppressing the impurity particles ionizing to a higher ionized state. On the other hand, the ionization rate distribution and the poloidal velocity influenced by the friction and thermal forces determine the impurity transport behavior.
Strongly magnetized plasma produced by interaction of nanosecond kJ-class laser with snail targets
Authors: Pisarczyk T , Renner O , Dudzak R , Chodukowski T , Rusiniak Z , Dostal J , Krupka M , Klir D , Domański J , Krasa J , Singh S , Cikhardt J , Batani D , Santos J , Burian T , Ehret M , Gajdos P , Zaras-Szydłowska A , Rosinski M , Tchórz P , Kustosz M , Vlachos C , Ospina-Bohórquez V , Jelinek S , Kocourkova G , Agrawal S , Borodziuk S , Krus M , Juha L
Published: March 2023

Magnetized plasma studies are necessary for many applied studies, including laser-driven inertial fusion, modeling astrophysically relevant phenomena, and innovative industrial and medical applications. An interesting method of generating highly magnetized plasma can be based on the interaction of a laser with spiral-shaped cavity (snail-like) targets. A target shaped in this way can represent the central area of a spherical pellet that is not irradiated radially, but rather through an entrance hole allowing the laser beam to almost impact its inner surface tangentially (Pisarczyk et al 2018 Sci. Rep.
8 17 895). In the reported experiment, snail targets of various diameters were irradiated by linearly or circularly polarized radiation of a Prague asterix laser system (PALS) iodine laser delivering ∼500 J, 350 ps and 1.315 μm pulses on targets. Three-frame complex interferometry demonstrated that plasma is generated on the entire inside and outside surfaces of the snail target, starting from the very beginning of the laser–target interaction. The time-resolved records of the magnetic field and the electron density distribution inside and outside the snail target characterize the changes in the structure of the magnetized plasma. Inside the target, the magnetic field survives long after the termination of the laser–matter interaction, namely longer than 10 ns. Compared to a circularly polarized laser pulse, the irradiation of targets with a p-polarized beam increases both the emission of hot electrons (HEs) and the intensity of the magnetic field. The emission of HEs is not isotropic, and their energy distribution cannot be characterized by a single temperature.
Discussion on the transport processes in electrons with non-Maxwellian energy distribution function in partially-ionized plasmas
Authors: Alvarez Laguna A , Esteves B , Raimbault J-L , Bourdon A , Chabert P
Published: March 2023

In a previous work (Alvarez Laguna et al 2022 Phys. Plasmas
29 083507), we have developed a non-linear moment model for electrons that self-consistently captures non-Maxwellian electron energy distribution function effects. The model does not rely in the local approximation and the transport coefficients are calculated by expanding the distribution function into Hermite polynomials and by taking moments of the Boltzmann equation, including the collision operator for elastic and inelastic collisions with arbitrary cross sections. This model captures the classical Fick’s, Fourier’s, and Ohm’s law as well as Soret, Dufour, and Peltier effects. In addition, novel non-local transport phenomena appear as a result of spatial gradients of the kurtosis of the distribution function. In this paper, we discuss on the transport effects by analyzing two collisional models: constant collision frequency and constant cross section. We estimate the order of magnitude of the transport processes in non-equilibrium electrons by analyzing the Langmuir probe measurements of a low-pressure argon inductively-coupled discharge. The results show that, under these conditions, the transport produced by the spatial gradients in the kurtosis of the distribution function produces a heat-flux contribution that is of the same order of magnitude as the Fourier and Dufour’s effects. These transport effects are beyond the local field or the electron gradient expansions, commonly used in the low-temperature plasma modeling.
Progress of a gas-electron-multiplier based camera (GEM) in investigating EAST macroscopic instabilities
Authors: Li Erzhong , Chen Y , Qu H , Zhou T , Chen F , Zhang L , Wang H , Duan Y , Liu H , Shen B
Published: March 2023

In recent years magneto-hydrodynamic instabilities have been observed in different experimental scenarios by a gas electron multiplier (GEM) camera, since it was installed on the Experimental Advanced Superconducting Tokamak (EAST). The GEM camera is set up outside the EAST vacuum chamber to record x-ray photons through a beryllium window, which has obtained valuable data for analysis: (1) neoclassical tearing mode (NTM) onset and (2) plasma disruption dynamics in the presence of magnetic islands. Although not precisely compared with theory and simulations, the GEM, in synergy with other diagnostics, reveals the significance of electron dynamics in NTM and plasma disruption. This is meaningful for understanding and modeling the disruption instability of fusion plasmas.
Nafion-Pt IPMC electroactive behavior changes in response to environmental nonequilibrium conditions
Authors: Arnold Allison , Su Ji , Sabolsky Edward M
Published: March 2023

Electroactive polymers (EAPs) continue to gain attention for their potential to offer unique and versatile solutions in the soft robotic and flexible electronic industries. Ionic polymer-metal composites (IPMCs) are a class of ionic-type EAPs which can be configured as capacitor actuators with very low voltage requirements (⩽5 V AC or DC). Their compact, portable, and lightweight properties, coupled with a biomimetic bending actuation response make them ideal for human-machine integrated technologies such as medical implants, active skins, and artificial muscles. This work tested the IPMC’s actuation and electrical response in varying saturation conditions (70% RH, 85% RH, 95% RH, and DI water liquid immersion) and voltage application schemes (direct current voltage (DCV) cycled, continuously applied, and relaxation responses upon voltage removal). This information was then used to establish actuation and back-relaxation response patterns through repetitive testing for statistical certainty. These demonstrated maximized actuation in water vapor conditions where the IPMC’s dielectric permittivity is maximized (ε′≅1.37×106), and the dissipation factor is minimized (tanδ=4.6). The response trends in vapor conditions are gradual but yield larger actuation ranges with increasing hydration. Liquid immersion restricts the IPMC’s range of motion but produces a sharper response pattern. These trends were validated against previously published IPMC actuator models. All of this creates a more pragmatic perspective on the potential of this technology which aids in the advancement of this material’s evolution towards viable real-world application configurations which capitalize on the material’s natural responses.
Effect of boundary dimension on energy absorption behaviour of shear thickening fluids under impact
Authors: Cui Xiaoyu , Wang Hongjian , Ye Lin , Fu Kunkun
Published: March 2023

This study examined the effect of boundary dimension on the energy absorption behaviour of concentrated shear thickening fluids (STFs). STFs were filled into a steel container with various depths and diameters and were impacted by a cylindrical striker. It was found that the energy absorption behaviour showed a response time after which an effective impact-resistant performance was demonstrated. Then, a simplified two-dimensional model was proposed to clarify the characteristics and mechanism of energy absorption behaviour of the impacted STF. For a relatively shallow STF, the energy absorption is mainly achieved by the axial compression of a semi-ellipsoid like jamming region underneath the striker with less radial boundary confinement. Therefore, an increase in depth weakens the energy absorption performance because of the delayed response time for the effective energy absorption. By comparison, the increase in diameter causes the reduction of interaction between the jamming region and the surrounding liquid-STF, slightly degrading the energy absorption performance. For a deep STF, this jamming region reaches to the lateral boundary prior to the effective energy absorption which is primarily achieved by both the compression and bending of the jamming layer supported by the underneath liquid-STF. Thus, an increase in diameter leads to a decrease in the energy absorption performance.
A large-step stick-slip rotary piezoelectric actuator with high velocity under low frequency and small backward motion
Authors: Xun Mingxin , Yu Hongpeng , Zhang Shijing , Chang Qingbing , Deng Jie , Liu Yingxiang
Published: March 2023

Stick-slip rotary piezoelectric actuators (SRPAs) are commonly used nowadays. However, most of them achieve high velocity by high exciting frequency, which causes the problems of wide power-source passband requirement and the wear of actuators. Moreover, their further applications are limited, due to the poor motion stability caused by the backward motion. To solve the problems, the stick-slip process is analyzed with kinematics, indicating that the large step contributes greatly to SRPAs for achieving high velocity under low operating frequency and backward motion elimination. Then a large-step SRPA is proposed, fabricated, and tested. The experiments show that under the sawtooth signal with 100 V and 400 Hz, the prototype can reach a maximum velocity of 1.854 rad s−1, benefiting from the large step (above 4.636 mrad). While other works require the exciting frequency of several kilohertz to reach the same level of velocity. Additionally, by increasing the step, the backward ratio decreases from 14.43% to 8.89% at the frequency of 1 Hz, and the minimum no-backward frequency decreases from 120 Hz to 60 Hz. The results indicate the effectiveness of the large step for solving the problems, which is significant for the design of SRPA.
Dispersion characteristics of surface wave in SCCS: theoretical analysis, numerical simulation and MASW-based NDT
Authors: Chen Hongbing , Gan Shiyu , Li Yuanyuan , Nie Xin
Published: March 2023

To fully validate the feasibility of multichannel analysis of surface waves (MASW)-based interfacial debonding detection for steel–concrete composite structures (SCCS), dispersion characteristics of surface waves in SCCS are systematically investigated using theoretical analysis and elaborate 3D numerical simulations. First, the influences of material strength and thickness of concrete core, steel plate thickness on the dispersion figures are analyzed based on the theoretical dispersion characteristic of Rayleigh wave. Scientific layering strategy, including single steel plate, double-layer, and three-layer medium assumptions, is investigated using the theoretical dispersion analysis of Lamb wave. Besides, the dispersion characteristics of surface wave in circular steel pipes are calculated to determine the appropriate theoretical dispersion curves for MASW measurement. Finally, the stress wave propagation processes in SCCSs with various internal structures, including stiffeners, studs, and diaphragms, as well as the debonding width, are simulated using 3D numerical simulation to validate the research finding of theoretical analysis and detectability of MASW-based non-destructive testing on interfacial debonding defects in rectangular and circular concrete-filled steel tubulars. Finally, the dispersion characteristics corresponding to displacement, velocity, and acceleration of surface waves are comparatively discussed. The research findings of this study are the cornerstone of experimental study and essential theoretical support for identifying interfacial debonding and bond-slip damage of SCCS components utilizing MASW method.
On-demand contactless programming of nonlinear elastic moduli in hard magnetic soft beam based broadband active lattice materials
Authors: Sinha P , Mukhopadhyay T
Published: March 2023

Engineered honeycomb lattice materials with high specific strength and stiffness along with the advantage of programmable direction-dependent mechanical tailorability are being increasingly adopted for various advanced multifunctional applications. To use these artificial microstructures with unprecedented mechanical properties in the design of different application-specific structures, it is essential to investigate the effective elastic moduli and their dependence on the microstructural geometry and the physics of deformation at the elementary level. While it is possible to have a wide range of effective mechanical properties based on their designed microstructural geometry, most of the recent advancements in this field lead to passive mechanical properties, meaning it is not possible to actively modulate the lattice-level properties after they are manufactured. Thus the on-demand control of mechanical properties is lacking, which is crucial for a range of multi-functional applications in advanced structural systems. To address this issue, we propose a new class of lattice materials wherein the beam-level multi-physical deformation behavior can be exploited as a function of external stimuli like magnetic field by considering hard magnetic soft beams. More interestingly, effective property modulation at the lattice level would be contactless without the necessity of having a complex network of electrical circuits embedded within the microstructure. We have developed a semi-analytical model for the nonlinear effective elastic properties of such programmable lattice materials under large deformation, wherein the mechanical properties can be modulated in an expanded design space of microstructural geometry and magnetic field. The numerical results show that the effective properties can be actively modulated as a function of the magnetic field covering a wide range (including programmable state transition with on-demand positive and negative values), leading to the behavior of soft polymer to stiff metals in a single lattice microstructure according to operational demands.
Fabrication and characterization of ZrO2 reinforced Fe-20Cr alloy composites
Authors: Singh Abhishek Kumar , Pandey Neeraj , Singh Rahul , Majhi Manas Ranjan
Published: March 2023

The reinforcement effects of the ZrO2 and the wear and mechanical behaviour of (Fe,Cr)-based alloy composites were investigated. The (100−x) (Fe80Cr20) -(x) ZrO2 composites were fabricated via powder metallurgy. The iron-chromium and ZrO2 powders were efficiently milled and mixed in ball mill. In the Fe80Cr20 alloy, the effect was investigated by changing the ZrO2 composition by 5%, 10%, and 15%. The blended powder mixture was cold compacted and sintered at 1030 °C. Scanning electron microscopy (SEM), elemental mapping, and x-ray diffraction techniques were utilized to assess the microstructural properties of the sintered composites. In addition, the mechanical properties such as hardness, flexural strength, and porosity were examined with variations in ZrO2 composites. The dry sliding wear tests with various normal loads and a constant sliding distance were used to find the composite’s wear behaviour. The composite containing 10% ZrO2 has shown the maximum flexural strength with 1470 MPa, and hardness 359.8 HV10 respectively, compared to 5% ZrO2 and 15% ZrO2. With a concentration of 10 wt.% ZrO2, the wear resistance is found to be significantly enhanced, while after 10 wt.% ZrO2, its properties deteriorate. In addition to having improved interfacial bonding, lower porosity, and microstructure uniformity, Fe80Cr20 (Fe-20 Cr) −10 wt% ZrO2 composites exhibit superior mechanical properties compared to other materials.
Gravitational collapse and formation of a black hole in a type II minimally modified gravity theory
Authors: De Felice Antonio , Maeda Kei-ichi , Mukohyama Shinji , Pookkillath Masroor C.
Published: March 2023

We study the spherically symmetric collapse of a cloud of dust in VCDM, a class of gravitational theories with two local physical degrees of freedom. We find that the collapse corresponds to a particular foliation of the Oppenheimer-Snyder solution in general relativity (GR) which is endowed with a constant trace for the extrinsic curvature relative to the time t constant foliation. For this solution, we find that the final state of the collapse leads to a static configuration with the lapse function vanishing at a radius inside the apparent horizon. Such a point is reached in an infinite time-t interval, t being the cosmological time, i.e. the time of an observer located far away from the collapsing cloud. The presence of this vanishing lapse endpoint implies the necessity of a UV completion to describe the physics inside the resulting black hole. On the other hand, since the corresponding cosmic time t is infinite, VCDM can safely describe the whole history of the universe at large scales without knowledge of the unknown UV completion, despite the presence of the so-called shadowy mode.
Primordial non-Gaussianity from the effects of the Standard Model Higgs during reheating after inflation
Authors: Litsa Aliki , Freese Katherine , Sfakianakis Evangelos I. , Stengel Patrick , Visinelli Luca
Published: March 2023

We propose a new way of studying the Higgs potential at extremely high energies. The Standard Model (SM) Higgs boson, as a light spectator field during inflation in the early Universe, can acquire large field values from its quantum fluctuations which vary among different causal (Hubble) patches. Such a space dependence of the Higgs after the end of inflation leads to space-dependent SM particle masses and hence variable efficiency of reheating, when the inflaton decays to Higgsed SM particles. Inhomogeneous reheating results in (observable) temperature anisotropies. Further, the resulting temperature anisotropy spectrum acquires a significant non-Gaussian component, which is constrained by Planck observations of the Cosmic Microwave Background (CMB) and potentially detectable in next-generation experiments. Constraints on this non-Gaussian signal largely exclude the possibility of the observed temperature anisotropies arising primarily from Higgs effects. Hence, in principle, observational searches for non-Gaussianity in the CMB can be used to constrain the dynamics of the Higgs boson at very high (inflationary) energies.
Addressing the Hubble and S
8 tensions with a kinetically mixed dark sector
Authors: Alexander Stephon , Bernardo Heliudson , Toomey Michael W.
Published: March 2023

We present a kinetically mixed dark sector (KMIX) model to address the Hubble and S
8 
tensions. Inspired from string theory, our model includes two fields: an axion, which plays a role
similar to the scalar field in early dark energy models, and a dilaton. This theory differs from
other axio-dilaton models aimed at the Hubble tension in that there is necessarily kinetic mixing
between the two fields which allows for efficient energy transfer from the axion into the dilaton
which has w ≈ 1. As a direct consequence of these dynamics, we find the model does not need
to resort to a fine-tuned potential to solve the Hubble tension and naturally accommodates a
standard axion potential. Furthermore, the axion will necessarily makeup a small (fuzzy) fraction
of Ωcdm once it begins to oscillate at the bottom of its potential and will suppress
the growth of perturbations on scales sensitive to S
8. Interestingly, the scale of the
potential for the dilaton has to be small, ≲ 𝒪(10 meV)4, suggesting the
possibility for a connection to dark energy. Implementing the dynamics for the background and
perturbations in a modified Boltzmann code we calculate the CMB and matter power spectra for our
theory. Exploring the parameter space of our model, we find regions which can accommodate a ∼ 
10% increase in H
0 from the Planck inferred value and S
8 values that are consistent with
large-scale structure constraints.
Theory of complex-coordinate transformation acoustics for non-Hermitian metamaterials
Authors: Li 李 Hao-Xiang 澔翔 , Tan 谭 Yang 杨 , Yang 杨 Jing 京 , Liang 梁 Bin 彬
Published: March 2023

Transformation acoustics (TA) has emerged as a powerful tool for designing several intriguing conceptual devices, which can manipulate acoustic waves in a flexible manner, yet their applications are limited in Hermitian materials. In this work, we propose the theory of complex-coordinate transformation acoustics (CCTA) and verify the effectiveness in realizing acoustic non-Hermitian metamaterials. Especially, we apply this theory for the first time to the design of acoustic parity–time (

P
T

) and antisymmetric parity–time (

A
P
T

) metamaterials and demonstrate two distinctive examples. First, we use this method to obtain the exceptional points (EPs) of the

P
T
/
A
P
T

system and observe the spontaneous phase transition of the scattering matrix in the transformation parameter space. Second, by selecting the Jacobian matrix’s constitutive parameters, the

P
T
/
A
P
T

-symmetric system can also be configured to approach the zero and pole of the scattering matrix, behaving as an acoustic coherent perfect absorber and equivalent laser. We envision our proposed CCTA-based paradigm to open the way for exploring the non-Hermitian physics and finding application in the design of acoustic functional devices such as absorbers and amplifiers whose material parameters are hard to realize by using the conventional transformation method.
Colossal negative magnetoresistance in spin glass Na(Zn,Mn)Sb
Authors: Yu Shuang , Peng Yi , Zhao Guoqiang , Zhao Jianfa , Wang Xiancheng , Zhang Jun , Deng Zheng , Jin Changqing
Published: March 2023

We report the study of magnetic and transport properties of polycrystalline and single crystal Na(Zn,Mn)Sb, a new member of “111” type of diluted magnetic materials. The material crystallizes into Cu2Sb-type structure which is isostructural to “111” type Fe-based superconductors. With suitable carrier and spin doping, the Na(Zn,Mn)Sb establishes spin-glass ordering with freezing temperature (T

f
) below 15 K. Despite lack of long-range ferromagnetic ordering, Na(Zn,Mn)Sb single crystal still shows sizeable anomalous Hall effect below T

f
. Carrier concentration determined by Hall effect measurements is over 1019 cm–3. More significantly, we observe colossal negative magnetoresistance (MR ≡ [ρ(H) − ρ(0)]/ρ(0)) of –94% in the single crystal sample.
Wavelength-tunable organic semiconductor lasers based on elastic distributed feedback gratings
Authors: Liu Chengfang , Lin He , Ji Dongzhou , Yu Qun , Chen Shuoguo , Guo Ziming , Luo Qian , Liu Xu , Lai Wenyong
Published: March 2023

Wavelength-tunable organic semiconductor lasers based on mechanically stretchable polydimethylsiloxane (PDMS) gratings were developed. The intrinsic stretchability of PDMS was explored to modulate the period of the distributed feedback gratings for fine tuning the lasing wavelength. Notably, elastic lasers based on three typical light-emitting molecules show comparable lasing threshold values analogous to rigid devices and a continuous wavelength tunability of about 10 nm by mechanical stretching. In addition, the stretchability provides a simple solution for dynamically tuning the lasing wavelength in a spectral range that is challenging to achieve for inorganic counterparts. Our work has provided a simple and efficient method of fabricating tunable organic lasers that depend on stretchable distributed feedback gratings, demonstrating a significant step in the advancement of flexible organic optoelectronic devices.
Fibers in smaller fascicles have lower activation thresholds with cuff electrodes due to thinner perineurium and smaller cross-sectional area
Authors: Davis Christopher J , Musselman Eric D , Grill Warren M , Pelot Nicole A
Published: March 2023

Objective. In nerve stimulation therapies, fibers in larger fascicles generally have higher activation thresholds, but the mechanisms are not well understood. We implemented and analyzed computational models to uncover the effects of morphological parameters on activation thresholds. Approach. We implemented finite element models of human vagus nerve stimulation to quantify the effects of morphological parameters on thresholds in realistic nerves. We also implemented simplified models to isolate effects of perineurium thickness, endoneurium diameter, fiber diameter, and fascicle location on current density, potential distributions (V
e), and activation thresholds across cuff geometries and stimulation waveforms. Using V
e from each finite element model, we simulated activation thresholds in biophysical cable models of mammalian axons. Main results. Perineurium thickness increases with fascicle diameter, and both thicker perineurium and larger endoneurial diameter contributed to higher activation thresholds via lower peak and broader longitudinal potentials. Thicker perineurium caused less current to enter the fascicle transversely, decreasing peak V
e. Thicker perineurium also inhibited current from leaving the fascicle, causing more constant longitudinal current density, broadening V
e. With increasing endoneurial diameter, intrafascicular volume increased faster than surface area, thereby decreasing intrafascicular current density and peak V
e. Additionally, larger fascicles have greater cross-sectional area, thereby facilitating longitudinal intrafascicular current flow and broadening V
e. A large neighboring fascicle could increase activation thresholds, and for a given fascicle, fiber diameter had the greatest effect on thresholds, followed by fascicle diameter, and lastly, fascicle location within the epineurium. The circumneural cuff elicited robust activation across the nerve, whereas a bipolar transverse cuff with small contacts delivering a pseudo-monophasic waveform enabled more selective activation across fiber diameters and locations. Significance. Our computational studies provide mechanistic understanding of neural responses across relevant morphological parameters of peripheral nerves, thereby informing rational design of effective therapies.
Study on Fine Wave Forecasting for Offshore Wind Farms
Authors: Zhang Guofeng , Yin Junjie , Cheng Chen , Han Qiqi , Li Lianbing
Published: March 2023

In order to ensure the safety of offshore operation and maintenance personnel and the smooth progress of major offshore projects, this paper establishes a prediction model of wave height and wave period based on support vector regression (SVR). First, the observation data of Xiaochangshan meteorological station from August 2021 to July 2021 are used to build a prediction model, and the data are preprocessed, and parameters are optimized. Then, the model trained with nine characteristics is evaluated for error under the test set, and the comparison image between the predicted value and the actual wind wave height and wind wave period is output. Finally, the observation data of the meteorological station in early August 2021 are used for verification of one hour and one day (24 hours). The experimental results show that the model can predict the wave height and wave period of the next hour and day, and the maximum error is not more than 0.4m, which can effectively provide a reasonable technical reference for the short-term prediction of the effective wave height of offshore waves.
The Real-time Fault Detection Method of Grounding the Circulating Current of Transmission Cable Based on the Wavelet Energy Spectrum of Module Component
Authors: Wang Qianjin , Yang Jinhai , Liu Xuefeng , Yu Lei , Lin Ying
Published: March 2023

Currently, the existing fault detection methods have problems in that the detection results are not in line with reality and the detection accuracy is too low when detecting the grounding circulation fault of transmission cables. This paper introduces the wavelet energy spectrum of module components to design and study the real-time fault detection method of grounding the circulating current of the transmission cable. In this study, the wavelet-based detection function that meets the requirements of fault detection is selected. On this basis, the traveling wave fault features are extracted by using the wavelet energy spectrum of the module component. Finally, the fault detection signal is decomposed in real-time, and the fault detection is realized according to the practical value of the reconstructed signal. The comparative experiment proves that the new detection method can get the detection result of the grounding current fault of the cable, which is more in line with the actual situation and has very high detection accuracy.
Research and Practice on Slope Monitoring of Power Grid Construction Based on IoT Technology
Authors: Zhang Chengwei , Liu Qin , Chen Bingqian , Huang Zhiting , Huang Xin , Yan Yan
Published: March 2023

In order to solve the shortcomings of traditional slope monitoring technology in automation, timeliness, and intelligence, this paper studies a slope monitoring system for high slopes in power grid construction based on power Internet of Things technology with characteristics of comprehensive perception, reliable delivery, and convenient application. By applying high-precision sensors, the plane and elevation monitoring accuracy of the system can reach a millimeter level. The layout principle of digital slope monitoring sensors is summarized and proposed according to traditional slope monitoring data in a power grid construction project in order to solve the relationship between actual slope monitoring demand and equipment investment. The slope monitoring system is applied in the three-level slope of a pilot project, and this technology realizes real-time judgment, efficient data transmission, and processing, making the obtained slope stability information more comprehensive, dynamic, and reliable.
Optimization of operation and maintenance path of offshore wind turbine based on ICS-BP
Authors: Zhang Guofeng , Yin Junjie , Cheng Chen , Li Lianbing , Xiao Yaze , Han Qiqi
Published: March 2023

An ICS-BP model for the operation and maintenance of the path optimization method is proposed to solve the path optimization problem based on the actual operation and maintenance of offshore wind turbines. The model comprehensively considers the impact of offshore wind speed and waves on the operation and maintenance ships, obtains the equivalent path matrix through the BP neural network model, and optimizes the path through the improved Cuckoo algorithm search (ICS). To verify the model’s effectiveness, the data of an offshore wind field is used, and the optimized path is greatly improved compared with other methods.
Array Sensor Output Signal Detection System Signal Conditioning Circuit Design
Authors: Lei Yang
Published: March 2023

The signal output by the array sensor is generally very weak, with a large dynamic range and a wide range of signal frequencies. In order to solve the problem of accurate measurement of weak signals with wide frequency and large dynamic range, this paper proposes a design method of sub-band filtering and variable gain amplifying circuit based on the analog switch, divides the signal into four frequency bands, and designs four groups of second-order voltage control filter, and adjust the magnification for different frequency signals, and only need to switch the corresponding resistance and capacitance to realize the switching of signal processing circuits of different frequency bands, which greatly optimizes the circuit structure. In order to reduce the interference in the transmission process, a single-ended differential circuit is designed to transmit the processed signal to the subsequent acquisition system for acquisition. After the simulation test, the signal conditioning circuit can effectively improve the signal-to-noise ratio of the detection signal and improve the measurement accuracy.
Research on 3D Modeling and Dynamic characteristics of wind turbine blade
Authors: Li Pengpeng , Tohti Gulbahar , Geni Mamtimin , Ma Wensong
Published: March 2023

In order to prevent blade resonance, reduce blade deflection, improve wind turbine power generation efficiency and wind energy utilization rate, the blade model of 3 kW wind turbine is established, and the natural frequency of wind turbine blade is analyzed. Based on the vibration theory, the effects of dynamic stiffening and rotational softening on the natural frequencies of blades are analyzed. Study the change rule of blade vibration mode under rotating speed of 0~300rpm, and analyze the influence of two effects on blade frequency. The results show that at low speed, the rotating softening effect of the blade is obvious, and the vibration frequency decreases; At high speed, the stress stiffening effect is more obvious, the vibration frequency increases, and the coupling vibration has greater destructiveness.
Modified Cam-clay Model Parameters M of Kunming Red Clay
Authors: Liu Xianru , Li Jianguang , Yi Ren , Zhao Kuangjie
Published: March 2023

Red clay is widely distributed in Kunming. At present, there are many engineering projects in Kunming, and many engineering projects are built on red clay. Therefore, it is very important to study the mechanical properties of red clay. Kunming red clay was remolded and prepared, and triaxial consolidation drainage tests of remolded saturated clay with the same water content and different dry densities were designed. Through the triaxial consolidation drainage test, the shear strength parameters of Kunming saturated red clay and the modified Cam-clay model parameters are obtained. The experimental results show that the modified Cam-clay model parameters of saturated red clay with the same water content and dry density are basically equal, and the larger the dry density is, the larger the modified Cam-clay model parameter M of saturated red clay is. The test results can provide reference data for engineering design in the Kunming area and modified Cam-clay model simulation in the Kunming area.
A Hybrid Algorithm for Two-dimensional and Three-stage Exact Packing Optimization Problem
Authors: Sun Yifan , Zhang Chuang , Liu Rui , Jia Limin , Qin Yong , Wang Zhipeng
Published: March 2023

In this paper, we study the packing optimization problem of square plates under the conditions that the cutting mode is guillotine cut, the number of cutting stages cannot exceed 3, and the order sequence is not considered. Because it is difficult to determine the constraint conditions in the process of stacking items into stacks, we divide the nonlinear integer programming model into two stages to establish: one stage is the process of stacking items into stacks followed by splicing them into stripes, and the other stage is the process of forming stripes. Finally, a packing optimization algorithm is proposed to solve the problem, which combines an improved bottom-up left-justified algorithm (BL algorithm), greedy algorithm, and iterative sequential value correction algorithm (ISVC algorithm) with a genetic algorithm (GA) as the core. Using this algorithm to solve the data after data preprocessing, the average plate utilization rate can reach 89.29%, which is 10.42% more than the final data without any processing.
Spatial awareness application using mixed reality for 3D X-ray CT examination
Authors: Kase H. , Nishizawa J. , Tabata K. , Takagi K. , Aoki T.
Published: March 2023

In the medical field, X-ray computed tomography (CT) is used to determine the size of defects and damage in an examined object, and to diagnose infectious diseases. Generally, data captured by 3D X-ray CT are viewed as images in three directions (sagittal, axial, and coronal) on a computer. However, augmented reality, virtual reality, and mixed reality are emerging as alternatives for imaging captured data for 3D X-ray CT and are used for medical simulations and educational purposes. Although these techniques are capable of 3D expression, they are limited to the representation of the surface structure of the object. The original function required of these technologies is to check the tomographic image of a specific part of the object by specifying any direction and position in three dimensions. This study proposes a method of representation in which a 2D digital imaging communication image is superimposed on a surface-rendered cross-section of an object. In addition, it proposes a pointing system using motion capture and a spatial reality display. The observer can confirm the object from any direction and understand the structure spatially. It can be moved and rotated with movements similar to actually holding, grabbing, moving, and rotating with hands. Moreover, the cross-section can be observed in any direction. In addition, by matching the respective scales of the device and application, the object can be represented with an error of less than 1 mm in the horizontal, vertical, and depth directions with respect to the actual object. Therefore, the proposed method is an effective 3D representation method in 3D X-rays, which are voxel data containing internal information. Furthermore, this method can easily indicate the desired location where the cross-section image can be viewed in a CT image. This study will help improve the efficiency of 3D X-ray inspection and surgery in the medical field.
Does rotation increase the acoustic field of view? Comparative models based on CT data of a live dolphin versus a dead dolphin
Authors: Wei Chong , Houser Dorian , Erbe Christine , Mátrai Eszter , Ketten Darlene R , Finneran James J
Published: March 2023

Rotational behaviour has been observed when dolphins track or detect targets, however, its role in echolocation is unknown. We used computed tomography data of one live and one recently deceased bottlenose dolphin, together with measurements of the acoustic properties of head tissues, to perform acoustic property reconstruction. The anatomical configuration and acoustic properties of the main forehead structures between the live and deceased dolphins were compared. Finite element analysis (FEA) was applied to simulate the generation and propagation of echolocation clicks, to compute their waveforms and spectra in both near- and far-fields, and to derive echolocation beam patterns. Modelling results from both the live and deceased dolphins were in good agreement with click recordings from other, live, echolocating individuals. FEA was also used to estimate the acoustic scene experienced by a dolphin rotating 180° about its longitudinal axis to detect fish in the far-field at elevation angles of −20° to 20°. The results suggest that the rotational behaviour provides a wider insonification area and a wider receiving area. Thus, it may provide compensation for the dolphin’s relatively narrow biosonar beam, asymmetries in sound reception, and constraints on the pointing direction that are limited by head movement. The results also have implications for examining the accuracy of FEA in acoustic simulations using recently deceased specimens.
Cu2−x
Se nanoparticles suppress cell proliferation and migration in hepatocellular carcinoma by impairing mitochondrial respiration
Authors: Liu Yali , Liu Wuyi , Li Guobing , Lai Wenjing , Hu Changpeng , Zhang Qian , Zhou Min , Lu Laichun , Huang Jingbin
Published: March 2023

Cu2−x
Se nanoparticles (Cu2−x
Se NPs) as a new therapeutic drug platform is widely used in disease treatment due to their strong near-infrared optical absorption. In recent years, with their continuous expansion of applications in different fields, their own biological effects have received increasing attention. However, little is known about the effect of Cu2−x
Se NPs on cancer cell. In this research, we found that Cu2−x
Se NPs inhibited proliferation of HepG2 cells (IC50: 15.91 μM) and SMMC-7721 cells (IC50: 43.15 μM) and they mainly induced cell cycle arrest at the G2/M phase. Moreover, Cu2−x
Se NPs inhibited HepG2 and SMMC-7721 cell migration and lamellopodia formation. Further studies indicated that Cu2−x
Se NPs impaired mitochondrial respiration by inhibiting electron transport chain complex activity, thus reducing adenosine triphosphate levels. The insufficient energy supply subsequently impaired actin cytoskeleton assembly, ultimately inhibiting HepG2 and SMMC-7721 cell proliferation and migration. These findings suggest that Cu2−x
Se NPs may have potentially antitumor activity, which might provide new insights of NPs into specific cancer treatment.
Atmospheric verification of emissions reductions on paths to deep decarbonization
Authors: Abdulla Ahmed , Telschow Fabian JE , Dohner Julia , Keeling Ralph F , Schwartzman Armin , Victor David G
Published: March 2023

A central challenge for sustaining international cooperation to cut global greenhouse gas emissions is confidence that national policy efforts are leading to a meaningful impact on the climate. Here, we apply a detection protocol to determine when the measurable signal of atmospheric CO2 can be distinguished from the noise of the carbon cycle and uncertainties in emission trends. We test that protocol with a database of 226 emission mitigation scenarios—the universe of scenarios vetted by the Intergovernmental Panel on Climate Change. These scenarios are descriptive of ‘baseline’ trajectories of emissions trends in the absence of new policies along with trajectories that reflect substantial policy efforts to stop warming at 1.5 °C–2 °C above pre-industrial levels, as embodied in the Paris Agreement. The most aggressive mitigation scenarios (i.e. 1.5 °C) require 11–16 years to detect a signal of demonstrable progress from the noise; 2 °C scenarios lengthen detection by at least a decade. As more climate policy analysts face the reality that goals of 1.5 °C–2 °C seem infeasible, they have developed ‘overshoot’ scenarios with emissions that rise above the agreed goal and then, later on, fall aggressively to achieve it. These pathways come at the political cost of a 1–2 decade delay in detection, even for the 1.5 °C scenarios. The Paris Agreement requires a global ‘stocktake’ that interrogates national mitigation efforts; our results suggest that this effort must grapple with the question of when the world can gain confidence that the diplomacy on climate is demonstrably making an impact.
Numerical study of microstructured fiber with concentric dual rings for supporting orbital angular momentum mode propagation
Authors: Wang Xiaohui , Yu Yongze , Gu Haoyu , Deng Dongdong , Wang Yang , Mao Shuai , Song Yingxiong , Pang Fufei , Zhuang Liyun , Yang Song , He Xiaofeng , Wei Dandan , Yang Yudong
Published: March 2023

A microstructured fiber with two concentric high-refractive-index rings is proposed to support more orbital angular momentum (OAM) beam propagations and OAM-based mode-division multiplexing (MDM) for improving the channel capacity and spectral efficiency. The two ring cores can be considered as two independent OAM channels without interference for enhancing more OAM channels. A finite element method (FEM) is employed to numerically study the properties of the designed fiber. A large effective refractive index difference between the adjacent OAM modes is achieved, which indicates that the propagated OAM modes can be well separated without multiple input, multiple output in each of the two rings. The calculated results demonstrate that a total of 80 OAM modes with a mode quality above 70% is achieved without any high-order radial modes from 1.5 to 1.6 μm, which contains 18 inner-ring OAM modes and 62 outer-ring OAM modes. Moreover, the designed fiber possesses low confinement loss (<2.2 × 10−7 dB m−1) and can be potentially utilized for high-capacity communications by OAM-based MDM.
Microstructure and wear resistance of laser cladding nano TiC/micro TiB2/C-276 composite coatings on 316L stainless steel
Authors: Liu He , Wang Xi , Yu Yuzhen , Yang Weiguang , Gao Hanpeng
Published: March 2023

Four metal-ceramic composite coatings were prepared by laser cladding (LC) using Hastelloy C-276, nano-TiC and micro-TiB2 as raw materials to improve the surface properties and extend the service life of 316L stainless steel. The microstructure and mechanical properties were analyzed by metallographic microscopy, scanning electron microscopy (SEM), x-ray diffraction (XRD), Vickers hardness experiments, and friction and wear testing. The TiC and TiB2 phases were detected in the coating, exhibiting homogenous distribution as their content increased. As a result, the strengthening effect of the coating was enhanced, improving microhardness relative to that of the 316L substrate. The wear test revealed that the Hastelloy coating exhibited poor wear resistance, but the addition of TiC and TiB2 particles improved the wear resistance by reducing the wear rate. The lowest average coefficient and wear rate were attained at 50% and 70% ceramic contents, respectively. However, abundant hard particles on the surface easily fell off during the wear, which further impeded the surface degradation and increased the friction coefficient.
Linguistic dissociation: A general theory to explain the phenomenon of linguistic distancing behaviours
Authors: Moore Ashley R
Published: March 2023

Across diverse yet largely unconnected reports, including language-focused research studies, psychotherapeutic case studies, literary biographies, and journalism, evidence exists of people distancing themselves from previously acquired linguistic resources, such as accents, dialects, and even named languages. In this article, I begin by discussing a selection of those reports, before arguing that there is a general process shared by these varied cases: linguistic dissociation. I then unpack my definition of linguistic dissociation, a relatively enduring psychosocial process in which an individual or group distances themselves from a set of linguistic practices already within their repertoire because those practices have come to connote a state of significant intersubjective disharmony, or contrasubjectivity. I construct a theoretical framework supported by related concepts—affective valence, evaluative conditioning, contrasubjectivity, prosubjectivity, and undesire—that provide a common theoretical vocabulary for discussing the phenomenon of linguistic dissociation and act as sensitizing tools for identifying and understanding heretofore unexamined linguistic distancing behaviours in other individuals and groups. I conclude by posing questions that future work on linguistic dissociation might answer.