bluuebunny/crossref_metadata_2025 huggingface dataset:
Wave propagation and band tails of two-dimensional disordered systems in the thermodynamic limit
Authors: Klatt Michael A. , Steinhardt Paul J. , Torquato Salvatore
Published: December 2022

Understanding the nature and formation of band gaps associated with the propagation of electromagnetic, electronic, or elastic waves in disordered materials as a function of system size presents fundamental and technological challenges. In particular, a basic question is whether band gaps in disordered systems exist in the thermodynamic limit. To explore this issue, we use a two-stage ensemble approach to study the formation of complete photonic band gaps (PBGs) for a sequence of increasingly large systems spanning a broad range of two-dimensional photonic network solids with varying degrees of local and global order, including hyperuniform and nonhyperuniform types. We discover that the gap in the density of states exhibits exponential tails and the apparent PBGs rapidly close as the system size increases for nearly all disordered networks considered. The only exceptions are sufficiently stealthy hyperuniform cases for which the band gaps remain open and the band tails exhibit a desirable power-law scaling reminiscent of the PBG behavior of photonic crystals in the thermodynamic limit.
Explicación multidimensional de la dinámica sociolingüística en Andalucía
Authors: Ávila Muñoz Antonio Manuel
Published: December 2022

Abstracta

El español hablado en la ciudad de Málaga puede representarse en la actualidad mediante un modelo teórico fiable y
compacto gracias a los diversos trabajos que desde hace más de veinticinco años se han encargado de describir, analizar y explicar
esta variedad lingüística del sur de España (Villena Ponsoda, 1996; Ávila Muñoz, 1994, entre otros). Las constantes observadas en todos estos trabajos nos
permiten afirmar que los hablantes de esta ciudad se mueven en un continuo de variación en el que las dinámicas de convergencia y
divergencia respecto al estándar están gobernadas por unos patrones de prestigio subyacentes que condicionan los usos lingüísticos
analizados. Este trabajo representa la situación descrita a partir de un modelo multidimensional que imbrica diversos planos: por
un lado, el correspondiente a la dimensión estándar-vernáculo; por otro, el que dibuja una dimensión gobernada por valores
correspondientes al estándar regional sólidamente asentado en Andalucía occidental. Las conclusiones son extrapolables al conjunto
de la realidad sociolingüística andaluza (y, muy probablemente, del español europeo meridional).
Privacy and everyday users of machine translation
Authors: Nunes Vieira Lucas , O’Sullivan Carol , Zhang Xiaochun , O’Hagan Minako
Published: December 2022

The concept of privacy is central to technology use, but in machine translation (MT) research the meaning of privacy, and what it represents to everyday MT users, are both often left unquestioned. This article examines user conceptualisations of privacy and their implications for the understanding of human-MT interaction. It draws on the privacy literature, on an online forum and on a survey of MT users. The findings show that while users have concerns about sharing information such as passwords, images, and contact details with MT providers, some of them can conversely see MT as a technology that provides privacy. The article discusses these findings in relation to the informational and relational dimensions of privacy. It argues that relational privacy, and the interpersonal exchanges for which MT can be used as a substitute, should be considered more explicitly in discussions of the societal implications of MT technology.
Relativity of superluminal observers in 1 + 3 spacetime
Authors: Dragan Andrzej , Dębski Kacper , Charzyński Szymon , Turzyński Krzysztof , Ekert Artur
Published: December 2022

We develop an extension of special relativity in

1
+
3

dimensional spacetime to account for superluminal inertial observers and show that such an extension rules out the conventional dynamics of mechanical point-like particles and forces one to use a field-theoretic framework. Therefore we show that field theory can be viewed as a direct consequence of extended special relativity.
Local foliations by critical surfaces of the Hawking energy and small sphere limit
Authors: Peñuela Diaz Alejandro
Published: December 2022

Local foliations of area constrained Willmore surfaces on a 3-dimensional Riemannian manifold were constructed by Lamm et al (2020 Ann. Inst. Fourier
70 1639–62) and Ikoma et al (2020 Int. Math. Res. Not.
70 6538–68), the leaves of these foliations are in particular critical surfaces of the Hawking energy in case they are contained in a totally geodesic spacelike hypersurface. We generalize these foliations to the general case of a non-totally geodesic spacelike hypersurface, constructing an unique local foliation of area constrained critical surfaces of the Hawking energy. A discrepancy when evaluating the so called small sphere limit of the Hawking energy was found by Friedrich (2020 arXiv:1909.02388v2 [math.DG]), he studied concentrations of area constrained critical surfaces of the Hawking energy and obtained a result that apparently differs from the well established small sphere limit of the Hawking energy of Horowitz and Schmidt (1982 Proc. R. Soc. A 381 215–24), this small sphere limit in principle must be satisfied by any quasi local energy. We independently confirm the discrepancy and explain the reasons for it to happen. We also prove that these surfaces are suitable to evaluate the Hawking energy in the sense of Lamm et al (2011 Math. Ann.
350 1–78), and we find an indication that these surfaces may induce an excess in the energy measured.
High-accuracy numerical models of Brownian thermal noise in thin mirror coatings
Authors: Vu Nils L , Rodriguez Samuel , Włodarczyk Tom , Lovelace Geoffrey , P Pfeiffer Harald , S Bonilla Gabriel , Deppe Nils , Hébert François , E Kidder Lawrence , Moxon Jordan , Throwe William
Published: December 2022

Brownian coating thermal noise in detector test masses is limiting the sensitivity of current gravitational-wave detectors on Earth. Therefore, accurate numerical models can inform the ongoing effort to minimize Brownian coating thermal noise in current and future gravitational-wave detectors. Such numerical models typically require significant computational resources and time, and often involve closed-source commercial codes. In contrast, open-source codes give complete visibility and control of the simulated physics, enable direct assessment of the numerical accuracy, and support the reproducibility of results. In this article, we use the open-source SpECTRE numerical relativity code and adopt a novel discontinuous Galerkin numerical method to model Brownian coating thermal noise. We demonstrate that SpECTRE achieves significantly higher accuracy than a previous approach at a fraction of the computational cost. Furthermore, we numerically model Brownian coating thermal noise in multiple sub-wavelength crystalline coating layers for the first time. Our new numerical method has the potential to enable fast exploration of realistic mirror configurations, and hence to guide the search for optimal mirror geometries, beam shapes and coating materials for gravitational-wave detectors.
Comment on ‘An ideal gas and the increasing (total) entropy principle: what is allowed in the PV plane and what is not’
Authors: Anacleto Joaquim
Published: December 2022

This comment deals with an issue in Marcella’s paper, 2022 Eur. J. Phys.
43 045104. We point out that the statement that quasistatic processes are necessarily free of dissipative effects is wrong, which led to an incorrect expression for entropy generation. We derive the correct expression, our aim being to remove persistent misconceptions in thermodynamics, in a constructive and pedagogical spirit.
Recovering a function from its integrals over conical surfaces through relations with the Radon transform
Authors: Terzioglu Fatma
Published: December 2022

This paper addresses the overdetermined problem of inverting the n-dimensional cone (or Compton) transform that integrates a function over conical surfaces in

R

n

. The study of the cone transform originates from Compton camera imaging, a nuclear imaging method for the passive detection of gamma-ray sources. We present a new identity relating the n-dimensional cone and Radon transforms through spherical convolutions with arbitrary weight functions. This relationship, which generalizes a previously obtained identity, leads to various inversion formulas in n-dimensions under a mild assumption on the geometry of detectors. We present two such formulas along with the results of their numerical implementation using synthetic phantoms. Compared to our previously discovered inversion techniques, the new formulas are more stable and simpler to implement numerically.
Accurate holographic cytometry using three-dimensional hydrodynamic focusing
Authors: Patel Yogesh M , Malik Ritika , Khare Kedar , Bahga Supreet Singh
Published: December 2022

We present a microfluidic holographic cytometry technique using three-dimensional (3D) hydrodynamic focusing for accurate visualization, classification, and quantification of the cells and particles from a mixture. Our approach uses high-resolution, single-shot digital holographic microscopy to image moving cells and particles in a specially-designed microfluidic device that orders the cells and particles in a single file close to the bottom wall of the channel. Our 3D-focusing microfluidic device allows high-magnification holographic imaging without the need for computationally-expensive numerical refocusing used by the existing holographic cytometry techniques. Our microfluidic device also prevents the clustering of cells and can be fabricated at a low-cost using micromilling. To demonstrate the efficacy of our method, we consider a challenging case of classification from a mixture of unstained red blood cells and polystyrene particles, which are otherwise indistinguishable in brightfield and phase-contrast microscopy. Through experiments with cell-particle mixtures with varying proportions, we show that our holographic cytometry technique can precisely count and classify the cells and particles based on their reconstructed phase values. Our holographic cytometry technique has the potential for label-free classification and quantification of infected cells for applications such as disease diagnostics, cancer research, and genomics.
Effects of alloying elements on diamond/Cu interface properties based on first-principles calculations
Authors: Han Jinjiang , Yang Xuefeng , Ren Ying , Li Ying , Li Yue , Li Zhengxin
Published: December 2022

Diamond/copper composites with high thermal conductivity and a variable thermal expansion coefficient are promising materials for thermal management applications. However, achieving the desired thermal conductivity of the composite material is difficult due to detachment or weak bonding between diamond and Cu. The interfacial properties of diamond/Cu composites can be improved using metal matrix alloying methods. In this study, we investigate the effects of alloying elements (B, Cr, Hf, Mo, Nb, Si, Ti, V, Zr) on the interfacial properties of diamond/Cu using first-principles calculations. Results showed that all alloying components could increase the interfacial bonding of diamond/Cu. Analysis of the electronic structure revealed that increased interfacial bonding strength after doping was the result of the stronger bonding of the alloying element atoms to the C atoms. The C atoms in the first layer of diamond at the interface formed wave peaks near the Fermi energy level after doping with B or Si atoms, facilitating electron–phonon interaction at the interface. The phonon properties of B4C and SiC were similar to those of diamond, which facilitated phonon–phonon coupling. B and Si were shown to be better alloying elements when interfacial bond strength and heat transfer were considered.
Spin triangle chain with ferromagnetic and antiferromagnetic interactions on the transition line
Authors: Ya Krivnov V , Dmitriev D V
Published: December 2022

We investigate spin-

1
2

anisotropic model of a linear chain of triangles with competing ferro- and antiferromagnetic interactions and ferromagneic Heisenberg interactions between triangles. For a certain ratio between interactions the one-magnon excitation band is dispersionless leading to an existence of localized-magnon states which form macroscopically degenerated ground states. The spectrum of excitations has a specific structure depending on the value of the triangle-triangle interaction. Such specific structure determines the low-temperature thermodynamics and, in particular, the temperature dependence of a specific heat. In the limit of strong anisotropy of interactions the spectrum has a multi-scale structure which consists of subsets rank-ordered on small parameter. Each subset is responsible for the appearance of the peak in the temperature dependence of the specific heat.
Instability of skyrmion lattice under microwave magnetic field due to single-q helimagnetic excitation mode
Authors: Li Yang , Wang Xuan , Ma Leikai
Published: December 2022

Composed of the three spiral magnetic vectors, the structure of skyrmion lattice (SkL) can be destructed by spin excitations in possibly two ways: one is to make decoherence of all the helices through the phase change of a certain spiral magnetic vector, and the other is to inhibit one or two spiral components while enhancing the others so that it becomes a magnetic structure of single or double magnetic vectors. Here, we present a micromagnetic study on the spin excitations of a two-dimensional SkL under the in-plane microwave magnetic field. By calculating the parameters describing the in-plane spin excitations mode, we find that the spin configuration tends to be an enhanced single-vector spiral magnetic structure due to the excitation modes under some specific frequencies so that the SkL will collapse to the topologically trivial state. Our results help to form a deeper understanding of the spin excitation in SkL under an ac magnetic field.
Atomic structure of intermetallic compound Nb5Si3 by new cluster transformation analysis method
Authors: Wang Q , Wang H P
Published: December 2022

The structure of Nb5Si3 at the atomic level is fundamental for identifying its complicated structure in atomic simulations and for further understanding the phase selection behaviors during the solidification of Nb-Si alloys. In this study, the structure of Nb5Si3 was investigated using deep-learning molecular dynamic simulations. The ideal βNb5Si3 is characterized by Nb-centered Voronoi polyhedrons (VPs) <0,0,12,3>, <0,0,12,2>, and Si-centered VPs <0,2,8,2>, <0,2,8,0>. Most initial VPs are distorted at high temperatures due to intense thermal perturbation. A new cluster transformation analysis (CTA) method was proposed to evaluate the stability of ideal VPs against perturbation and predict the possible transformations of the initial VPs in atomic simulations. Most transformations of the initial VPs in βNb5Si3 originate from distortions at the edges of the Nb-centered VPs and the faces/vertices of the Si-centered VPs. The distorted VPs in βNb5Si3 at high temperatures are dominated by <0,1,10,4>, <0,1,10,5>, <0,2,8,1> and <1,2,5,3> VPs, which are predicted as the primary transformations by the CTA.
Eye-lens dose rate conversion factors due to hot particles and surface contaminations on the cornea
Authors: Dubeau Jacques , Djeffal Salah , Sun Jiansheng , Ali Fawaz
Published: December 2022

In 2012, the International Commission on Radiological Protection issued new recommendations, in publication 118, regarding the dose limits to the eye-lens. New analyses of historical exposure data had indicated that radiation-induced cataracts may appear at lower doses than previously assumed. This spurred largescale efforts in a variety of fields including dosimetry, radiation effects simulations, and the review of national regulatory limits. On the simulation side, much work led to the publication of dose rate conversion factors (DRCFs), to calculate the dose to the radiosensitive part of the eye-lens, and to the whole eye-lens as functions of the incident fluence of electron, photon, positron, and neutron radiation. The standard, ISO-15382 (2015 Radiological Protection—Procedures for Monitoring the Dose to the Lens of the Eye, the Skin and the Extremities), from the International Organization for Standardization (ISO), stated that the direct contact of a hot radioactive particle on the eye-lens represents a special contamination condition that must be considered. The aim of this work was to produce tabulated data of eye-lens dose rates, per activity (MBq), for a variety of radionuclides. In this work, the dose to the eye-lens from contamination directly in contact with the cornea, expressed in terms of DRCFs for eye-lens, in units of Gy h−1 MBq−1, are presented for 102 radionuclides of interest. These radionuclides were selected as they had been considered by the International Atomic Energy Agency of importance for skin dose. The method consisted of two steps. The first was the determination of the DRCFs for mono-energetic electrons and photons for a hot particle in contact with the eye-lens, followed by the folding of these quantities with the emissions of the radionuclides of interest. Contributions from spontaneous fission neutrons were considered separately. Exposure geometries for spherical hot particles of different dimensions, materials and locations on the cornea were considered. In addition, partial surface coverage of the cornea, consistent with an accidental exposure to a contaminated liquid, was also modelled. Resulting radionuclide DRCFs were verified, for a few specific geometries and radionuclides with dedicated Monte Carlo simulations. The final data are presented in several tables included in this paper.
Micro-machining of in-fibre 45° mirror optical fibre cantilever for dual-axis acceleration measurement
Authors: Li Jun , Li Jia Wei , Zhang Jia Rui , Li Kuo , Ma Tian , Wang Wei Feng , Zhai Xiao Wei , MacPherson William N , Maier Robert R J , Hand Duncan P
Published: December 2022

Focused ion beam (FIB) machining has been demonstrated to be capable of fabricating nano- and micro-scale structures. In this paper we demonstrate techniques to design and fabricate 45° micro-mirrors into the end of multi-core fibres using FIB processing. The mirrors are fabricated by a two-step process: a scanning process which is used to make a rough cut followed by a polishing process to create an optical surface finish mirror. The machined 45° mirrors can be accurately aligned with optical fibre cores, which avoids issues associated with the alignment of external turning mirror components. Proof-of-concept demonstration shows that the fabricated structure is capable of measuring two-axis acceleration interferometrically with a linear response from 0.2 to 4 g and an rms. error of 0.03 g. Acceleration measurements of frequency response up to 700 Hz and cross-sensitivity of ∼4.3% are demonstrated.
Deep learning based distortion restoration and defect segmentation from linear scanning camera images
Authors: Wang Zhengfang , Sui Qingmei , Guo Wei , Zhang Jiaqi , Li Zhenpeng , Yang Yujie , Shang Yiheng , Zang Lilin , Yu Shaohuai
Published: December 2022

With long-term operation of tunnels, the surface of tunnel lining is prone to crack, spalling, water leakage and other defects. Therefore, the detection of tunnel surface defects has become an important process to ensure the safety of tunnel operation. Linear scan cameras have become the main way of tunnel surface defect detection because of their ultrahigh resolution and ultrahigh scanning frequency. However, in the process of collecting tunnel surface images at high speed, the linear scan cameras are easy to cause images distortion, which leads to reduction of tunnel defect identification accuracy. Thus, this paper proposes a tunnel surface distortion image restoration method based on a supervised generative adversarial network, which introduces an attention mechanism to guide the method to calibrate the weights of feature channels. It solves the problem of distortion in the process of images acquisition of the linear scan cameras. Then, to deal with the difficulty in identifying small-size tunnel defects in complex tunnel environments, this paper combines a backbone network with a multi-scale feature fusion module based on the You Only Look At CoefficienTs (YOLACT) network, which enhances the feature extraction ability of the network and improves the accuracy of tunnel surface defect identification.
An incipient fault diagnosis method based on Att-GCN for analogue circuits
Authors: Yang Jingli , Li Ye , Gao Tianyu
Published: December 2022

Incipient faults for analogue circuits in modern electronic systems are difficult to diagnose due to poor fault features. To address this issue, a method based on the attention weighted graph convolution network (Att-GCN) is proposed in this paper. The structural and data features of samples are jointly extracted to mine the effective characteristics from incipient faults. First, a wavelet packet energy transform and a probabilistic principal component analysis (ProbPCA) are employed to enhance the sample fault information. Then, the distance clustering method is deployed to construct the sample set into a non-European structure sample graph, where the structural features of fault samples are preserved. Second, an Att-GCN, which combines the spatial-domain graph convolution network and improved self-attention mechanism, is constructed to extract the structural features and data features to obtain more effective fault information. Additionally, the multisample dropout method is introduced to reduce network overfitting in the training process. To assess the method’s actual performance for fault diagnosis, experiments are carried out in the Sallen–Key bandpass filter circuit, the four-op-amp biquadratic filter circuit and the amplifier board circuit. The outcomes indicate that this method improves the incipient fault diagnosis accuracy for analogue circuits.
Fault diagnosis of wind turbines with generative adversarial network-based oversampling method
Authors: Yang Shuai , Zhou Yifei , Chen Xu , Deng Chunyan , Li Chuan
Published: December 2022

Due to the complex working environment, effective fault data from wind turbine gears are often difficult to obtain. Aiming at this practical issue, a generative adversarial network (GAN)-based oversampling method is proposed in this paper, which can achieve fault classification with a small dataset. In the initial stage, wavelet packet transform is applied to generate and extract features. Then, the optimal discriminator and generator trained by GAN are used to generate data to compensate for the imbalanced fault dataset. Random forest, eXtreme gradient boosting and support vector machines are chosen to classify a real dataset, imbalanced dataset and generated dataset, respectively. Experiments indicate that the data generated by the proposed method stay at the same distribution as the real data. Therefore, for small or imbalanced dataset situations, the proposed method could be a solution to compensate for the dataset.
Depinning transition of travelling waves for particle chains
Authors: Baesens C , MacKay R S , Qin W-X , Zhou T
Published: December 2022

In this paper we apply Aubry–Mather theory for equilibria of 1D Hamiltonian lattice systems and the theory of invariant ordered circles to investigate the depinning transition of travelling waves for particle chains. Assume A < B are two critical values such that the particle chain has three homogeneous equilibria if the driving force

F
∈
(
A
,
B
)

. It is already known that there exist transition thresholds

F
c
−

⩽

F
c
+

of the driving force such that the particle chain has stationary fronts but no travelling fronts for

F
c
−

⩽
F
⩽

F
c
+

and travelling fronts but no stationary fronts if

A
<
F
<

F
c
−

or

F
c
+

<
F
<
B

. The novelty of our approach is that we prove the transition threshold

F
c
+

(

F
c
−

) coincides with the upper (lower) limit of the upper (lower) depinning force as the rotation number tends to zero from the right. Based on this conclusion, we demonstrate that when the driving force

F
∈
(

F
c
−

,

F
c
+

)

, besides stationary fronts there are various kinds of equilibria with rotation numbers close to zero such that the spatial shift map has positive topological entropy on the set of equilibria. Furthermore, we give a necessary and sufficient condition for the absence of propagation failure, i.e.

F
c
−

=

F
c
+

, in terms of a minimal foliation. Finally we show that

F
c
±

are continuous with respect to potential functions in C
1 topology.
Power exhaust and core-divertor compatibility of the baffled snowflake divertor in TCV
Authors: Gorno S , Colandrea C , Février O , Reimerdes H , Theiler C , Duval B P , Lunt T , Raj H , Sheikh U A , Simons L , Thornton A , Team The TCV , MST1 Team The EUROfusion
Published: December 2022

A baffled snowflake minus low-field side (SF-LFS) is geometrically-optimised in tokamak à configuration variable, increasing divertor neutral pressure, to evaluate the roles of divertor closure (comparing with an unbaffled SF-LFS) and magnetic geometry (comparing with a baffled single null (SN)) in power exhaust and core-divertor compatibility. Ohmically-heated L-mode discharges in deuterium, with a line-averaged core density of approximately

4.7
×

10

19

 m−3, are seeded with nitrogen to approach detached conditions. Baffles in the SF-LFS configuration are found to reduce the peak outer target heat flux by up to

23
%

, without significantly affecting the location of the inter-null radiation region or the core-divertor compatibility. When compared to the baffled SN, the baffled SF-LFS exhibits a reduction in the outer target heat flux by up to

66
%

and the ability to balance the strike-point distribution of heat flux. These benefits are less significant with N2 seeding, with similar peak target quantities (such as heat flux, electron temperature and ion flux) and divertor radiated power. Despite a radiating region located farther from the confined plasma for the SF-LFS than the baffled SN, no change in core confinement is observed. Core effective charge even indicates an increase in core impurity penetration for the SF-LFS. These experiments constitute a good reference for detailed model validations and extrapolations, exploring important physics such as core impurity shielding and the dependence of divertor cross-field transport on magnetic geometry.
Dynamic modeling and disturbance rejection compensation for hysteresis nonlinearity of high voltage piezoelectric stack actuators
Authors: Li Weiguang , Liu Ke , Yang Zhichun , Wang Wei
Published: December 2022

High voltage piezoelectric stack actuators (HVPSA) are widely used in the field of active vibration control of engineering structures due to their strong load capacity, fast response rate, and high mechanical output efficiency. However, their inherent hysteresis will have a direct impact on the stability and control efficiency of the piezoelectric active control system. To compensate the hysteresis nonlinearity of HVPSA, a high-precision dynamic hybrid method based on linear active disturbance rejection control (LADRC) is proposed. Starting from the hysteresis analysis of piezoelectric actuators, an exponential function butterfly-shape hysteresis operator is constructed and combined with the asymmetric Bouc–Wen model to present a novel hybrid static hysteresis model. In order to implement rate-dependent hysteresis modeling, the Hammerstein rate-dependent hysteresis model of HVPSA is further established, and its inverse model is built for feedforward compensation. Subsequently, the LADRC is used to adjust the driving voltage in real time to form the hysteresis closed-loop compensator of HVPSA. The experimental results show that the Hammerstein rate-dependent hysteresis model established has satisfactory modeling accuracy in the working voltage range and frequency band under consideration. Furthermore, compared with the traditional inverse model feedforward compensation strategy, the proposed hybrid compensation method based on LADRC improves the compensation efficiency by more than 11% and reduces the hysteresis nonlinearity of HVPSA to less than 3%, with strong anti-disturbance ability.
Feynman path description of the effects of dephasing of spatial coherences on the transmission and reflection probabilities through a one-dimensional potential
Authors: Nagalla Karna , Walls Jamie D
Published: December 2022

In this work, we examine the effects of spatial dephasing of coherences on the transmission and reflection probabilities for electrons with energy E incident to a one-dimensional rectangular barrier of height V
0. Statistical models are presented where the coherence between different scattering pathways or ‘Feynman paths’ undergo dephasing over a length scale, L

ϕ
. For incident waves with E > V
0, three different dephasing models that attenuate the contributions of spatial coherence to the transmission and reflection probabilities while preserving unitarity (i.e., conserving charge) were investigated. In the tunneling regime (incident waves with E < V
0), however, preserving unitarity requires L

ϕ
→ ∞ , suggesting that elastic tunneling through a rectangular barrier is 100% spatially coherent for these dephasing models. However, wave absorption models are shown to preserve unitarity in the tunneling regime, which is not the case for scattering above the barrier.
Surface DBD plasma microbubble reactor for degrading methylene blue
Authors: Jakob Henrike , Paliwoda Matthew , Rovey Joshua L , Kim Minkwan
Published: December 2022

Water contaminants such as endocrine inhibitors, pharmaceuticals, and chlorine treatment by-products are only recently being identified as significant hazards to human health. Since current chlorine treatment does not address many of these compounds and conventional ozone processing is not seen as an economic alternative, water adjacent plasma treatment has been investigated as a more efficient and effective decontamination method. This work investigates the use of a surface dielectric barrier discharge electrode as a reduced discharge voltage portable plasma water treatment method. The gas passes through holes in the electrodes, normal to the discharge surface, so that the entire cross-sectional area of the feed gas is exposed to plasma, prior to passing through a hydrophobic filter and bubbling into the water. The decontamination effectiveness is quantified by measuring the degradation of methylene blue with absorption spectroscopy. Studies of the different processing parameters (treatment time, solution volume, initial concentration, electrode-filter distance, and gas flow rate) clarify the potential range of performance for this plasma treatment configuration. The setup has a yield energy of 0.45 g/kW·h at 25 ml of 1 mg/100 ml methylene blue treated over 5 minutes for a 92% degradation. The degradation rate is dependent upon the volume ratio of air to methylene blue solution, suggesting a first order chemical reaction process. The reaction rate is increased by increasing the quantity of either reactant. There is no change in the degradation between when the plasma is 1 mm or 1 cm from the water surface.
Energy computation and multistability in a class of second-order chaotic systems with simple nonlinearities: numerical, experimental and analytical results
Authors: Sivaganesh G , Srinivasan K , Fonzin Fozin T , Raja Mohamed I
Published: December 2022

The present work is aimed at the design, implementation and analysis of generic new second-order non-autonomous chaotic systems with simple nonlinear functions that have algebraically simple representations in mathematical form. These systems involve simple second-order non-autonomous ordinary differential equations with different simple nonlinearities like

G
(
x
)
(
=

x

2

,
∣
x
∣
,
max
(
x
)
and
min
(
x
)
)

. The present study deals with numerical simulation, experimental analog circuit simulation results to demonstrate the ordered and chaotic phenomena being exhibited by these systems. Of most interest the striking phenomenon of multistability is uncovered for certain nonlinearities. Coexisting attractors are harnessed through the offset boosting approach. Also, the Hamilton energy is established through the Helmholtz theorem. It is found that both methods can be exploited as a non-bifurcation approach in characterizing multistability in the model. Further, analytical solutions developed for systems with certain nonlinearities are presented and the chaotic behavior of the systems studied using the solutions validating the numerical and experimental results are reported.
Doped potassium dihydrogen phosphate single crystals with enhanced second-harmonic generation efficiency: an investigation of phase purity, nonlinear, piezoelectric, optical, and crystalline qualities
Authors: Priyadharshini R S , Saravanan M
Published: December 2022

We investigated the impact of itaconic acid (ITA) on potassium dihydrogen phosphate (KDP) aimed at concentrations of 1, 3, and 5 mol % on Single Crystal x-ray Diffraction, Fourier Transform Infra-Red, absorption of optical charm, Powder XRD, improved second Harmonic Generation competency, and third order non-Linearity of fully grown solitary crystals formed by slow cooling (Low Temperature Solution Growth). The crystals were crushed into a powder with micron-sized crystals for x-ray diffraction research. The Powder XRD spectrum of different ITA doped KDP concentrations showed fewer peaks with higher intensities than pure KDP crystals. Doping in the KDP crystal matrix accelerate growth in the [200] plane. Despite vibration assignment modes of ITA doped KDP, the FT-IR spectrum shows doping materials in KDP crystalline media. ITA doped KDP showed 90% optical transmission in UV–vis-NIR spectroscopy, whereas pure KDP possessed 60%. The dielectric investigation found that doped KDP crystals had lower dielectric loss and greater dielectric constants than pure counterparts. In pure and doped crystals, piezoelectric effects and second harmonics are premeditated. Using the Z scan approach, we were able to assess the third order nonlinear optical behaviour of pure crystal samples as well as the effects of self-defocusing caused by doping of ITA in KDP. ITA doping contributes to the growth, nucleation, and induction period. Doping concentration initially accelerated growth. Photoluminescence study shows that fully formed crystals have fewer defects. High Resolution XRD study determined crystal quality.
Analysis of task-related MEG functional brain networks using dynamic mode decomposition
Authors: Partamian Hmayag , Tabbal Judie , Hassan Mahmoud , Karameh Fadi
Published: December 2022

Objective. Functional connectivity networks explain the different brain states during the diverse motor, cognitive, and sensory functions. Extracting connectivity network configurations and their temporal evolution is crucial for understanding brain function during diverse behavioral tasks. Approach. In this study, we introduce the use of dynamic mode decomposition (DMD) to extract the dynamics of brain networks. We compared DMD with principal component analysis (PCA) using real magnetoencephalography data during motor and memory tasks. Main results. The framework generates dominant connectivity brain networks and their time dynamics during simple tasks, such as button press and left-hand movement, as well as more complex tasks, such as picture naming and memory tasks. Our findings show that the proposed methodology with both the PCA-based and DMD-based approaches extracts similar dominant connectivity networks and their corresponding temporal dynamics. Significance. We believe that the proposed methodology with both the PCA and the DMD approaches has a very high potential for deciphering the spatiotemporal dynamics of electrophysiological brain network states during tasks.
Low-carbon economic dispatch of integrated energy system considering carbon trading and integrated demand response with CCER
Authors: Wei Nan , Jia Yanbing , Tao Hongfei , Yan Zhikun , Chen Junxian
Published: December 2022

Under the background of ‘double carbon,’ to promote the transformation of generating units to new energy power generation in an integrated energy system and better realize carbon trading functions, the paper gives a carbon trading model considering CCER and a low carbon economy scheduling model considering joint demand response. First, consider the nationally certified voluntary emission reductions for wind power applications in the traditional carbon trading model, and improve the benefit of investment in renewable energy projects to strengthen the conversion of traditional energy structures to new energy structures while reducing the amount of carbon emissions in the system. Second, price-based and alternative responses are introduced on the user demand side to accurately model and optimize the load curve. The model is solved by using the CPLEX solution toolbox, and the correctness of the given model is proved by simulation.
Energy storage capacity configuration in multi-energy complementary systems
Authors: Ding Yafei , Shen Xuhui , Song Yunting , Li Zheng , Cao Hao
Published: December 2022

To solve the problems of high peak shaving pressure, low energy utilization rate and poor economy of the multi-energy complementary system caused by the integration of wind and solar power into the grid, the research builds a two-layer optimization model of energy storage and routine power peak shaving based on the predicted output and load of wind and solar power on a typical day. The outer layer aims at the maximum annual net profit of the muit energy complementary system, and the inner layer aims at the lowest daily operating cost. The improved PSO and nonlinear programming are used to coordinate and solve the problem to determine the multi-energy complementary system’s intra-day peak-shaving scheduling method, which is reasonable and reasonable. Finally, an example of an actual power grid is analyzed, and the results show that the multi-energy complementary system after optimal configuration of energy storage can greatly raise the level of new energy consumption and has good economy.
Research on Application of High-Frequency Coupler in Monitoring Unit of Circuit Patrol Monitor
Authors: Guo Fei , Li Hui , Ma Chao , Meng Wei , Chen Jianwei , Wang Qingquan
Published: December 2022

In recent years, power electronics industries have developed rapidly, and new electromagnetic materials have been continuously used. As the core component of electronic components, the high-frequency coupled magnetic core is the main component in the manufacture of current transformers and other devices. In this paper, we have developed a monitoring unit for circuit patrol monitor. It uses materials owning broadband, constant conductance, and low loss as the magnetic core of the high-frequency coupler, which improves the accuracy of loop state monitoring. The monitoring unit can realize the accurate identification of normal connections, open circuits, short circuits, and loop rectification of the transformer under different loads, provide a scientific basis for industrial and commercial power quality monitoring, and regulate the user’s electricity consumption behavior.
Analysis of Unit Commitment of Coal-fired Units in a Power Base of Cross-area DC Transmission Lines Under Dual Carbon Targets
Authors: Yuhan Liu , Zhulei  , Zhong Chen , Liang Chen , Yuanchen Wang , Qishuai Huang
Published: December 2022

China has announced achieving a carbon peak before 2030 and neutralization by 2060. Cross-area UHVDC transmission provides a feasible way for the new energy base to transmit power to the load center on a large scale. Usually, the dispatching of coal power units of DC transmission line power base is divided according to the equal proportion of unit capacity, this paper takes all the units as a group and proposes a unit commitment solution to realize lower carbon emission. As the capacity of new energy in the power base increases, this paper also considers the generation margin for new energy to do the optimization simulation. The results show that by operating coal-fired units as a group, it operates in a more economic and environmentally friendly way.
Temperature field analysis of dry iron core reactor
Authors: Liu Jiaming , Zhao Yanzhen
Published: December 2022

The hot spot temperature of a dry-type iron core reactor is important for its pre-design and optimal design. To precisely study the hot spot temperature and temperature distribution law of dry iron core reactor, this paper firstly studied the loss of reactor, including coil loss and core loss, and obtained the calculation method of reactor loss. Then, the normal working environment of the dry core reactor is analyzed, and the temperature field simulation is carried out for a three-phase dry core reactor with an inductance value of 11.561 mH and capacity of 10 kV, and the hot spot temperature and temperature distribution law of this reactor are obtained and analyzed through reasonable material setting and heat dissipation method setting. Finally, the accuracy and validity of the simulation results are verified by the actual temperature rise experimental data. The research results provide a theoretical basis for structure optimization and online monitoring of the dry core reactor.
Research on Electromagnetic Disturbance Characteristics of Mining Frequency Converter Based on Frequency Domain Analysis
Authors: Lu Yujia , Sui Longpeng , Dong Leiming , Jiao Chaoqun , Zhao Zhibin , Zhang Xiumin , Jia Xiaoqian
Published: December 2022

With the continuous improvement of the technical level of coal mine equipment, low-voltage converters have been used in many types of underground electromechanical equipment because of their energy-saving and high-efficiency features. However, low-voltage mining converters generate a lot of electromagnetic disturbances during operation, which may cause the surrounding electrical equipment to work abnormally. Therefore, it is important to study the electromagnetic disturbance characteristics in the frequency domain of the mining converter. This paper takes a typical ZJT series mining low-voltage AC converter as the research object, models and simulates the whole mining converter and its main interference source IGBT, and analyses and compares the measured electromagnetic harassment data to obtain the electromagnetic harassment trend characteristics of IGBT in the converter, which is of certain guiding significance for the development of immunity test standards of the equipment or system around the mining converter.
Research on Identification and Regulation of Power Load Characteristics Considering Demand Side Response
Authors: Yang Jing , Deng Zhidong , Liu Kunpeng , Gong Lihua
Published: December 2022

Due to the uncertainty of distributed generation output, it will cause some interference with the identification and regulation of load characteristics on the demand side, which is not conducive to improving the net load characteristics. To solve this problem, the identification and regulation methods of user power load characteristics considering demand side response are studied. When the user load demand is high, the demand response generated by the electricity price incentive has a greater regulating effect on the transferable load. According to the transient and steady-state characteristics of the load, the real-time data of electrical equipment are identified, and the composition and change of the user’s electrical load characteristics are obtained. At the beginning of the regulation period, the power enterprise receives the load characteristics on the demand side according to the user demand, determines the charging state and operation time of the power grid, and implements the operation of power consumption, idling, or discharging to minimize the cost. The test results show that this design method can accurately identify the load characteristics, and has a good effect in transferring peak load and alleviating peak valley difference, which provides a basis for users’ power use decisions.
Design of a Modular High-Accuracy, High-Voltage Charging Power Supply Prototype
Authors: Zhang Yuqiang , Shangguan Jingbin , Gao Daqing , Gao Jie
Published: December 2022

In order to realize the upgrade of the Kicker system for the Heavy Ion Research Facility in Lanzhou, the design of a modular high-accuracy, high-voltage charging power supply based on a full-bridge LC series resonant topology was proposed. More specifically, the parametric design of one of the modules, including the main circuit and transformer design, was introduced, and the realization principle of high precision was proposed. After simulation verification, a 35 kW/80 kV charging power supply prototype was developed. The experimental result shows that the power supply’s output voltage can be adjusted between 0~80 kV, and the output accuracy is better than 1‰.
Study on Technical Parameters of X-ray Stereoscopic Imaging of Ablative Defects for Water Blocking Buffer Layer in High Voltage Cable
Authors: Xie Yi , Liu Jianjun , Feng Chao , Zhang Jun , Liu Sanwei , Chen Dabing
Published: December 2022

In this paper, the technical parameters of the X-ray stereoscopic imaging of the ablative defects of water blocking buffer layer in the high-voltage cable are studied by theoretical analysis and laboratory experiment. The works give technical recommendations about the voltage, current, and sampling volume, which provide a reference for the standardization of the technical parameters of X-ray stereoscopic imaging of ablative defects of the water-blocking buffer layer in the high-voltage cable.
Calculation Method of Consumption Capacity of Photovoltaic Distribution Network Based on Time Series Production Simulation
Authors: Huang Kai , Jiao Bo , Zhang Shibiao , Liu Hongliang , Sun Lin
Published: December 2022

Aiming at the problem that the existing calculation methods have a big difference in the calculation results and the actual calculation results, in order to improve the accuracy of the calculation results, the time series production simulation theory is introduced, and the calculation method of the consumption capacity of photovoltaic distribution networks is studied. According to the actual operation of the distribution network, this paper adjusts the power supply pattern of the photovoltaic distribution network; then, this paper checks the frequency regulation capacity of the photovoltaic distribution network; finally, the time series production simulation is introduced to simulate the production of the photovoltaic distribution network with the absorption capacity. The comparative experiment shows that the new calculation method is more accurate than the existing calculation method based on uncertainty optimal power flow, and it can provide a data basis for the planning and construction of photovoltaic distribution networks.
Research on Micro-Water Treatment Technology of High-Voltage SF6 Equipment without Power Failure
Authors: Tang Xin , Chen Changlei , Yang Xin , Liu Weidong
Published: December 2022

With the frequent occurrence of high-voltage SF6 equipment-related problems in recent years, the exceedances of micro-water content and decomposition products of SF6 and other problems are getting increasingly worse. The routine solution involves multiple processes, including powering off the equipment, recovering the SF6 gas in the equipment, flushing, injecting new SF6 gas, and conducting the voltage withstand test, which requires a huge number of manpower and material resources. Besides, the operating process is risky, and power cutting and re-supplying increase the operational risk and impair the reliability of the grid in the power supply. This paper mainly explores an efficient, safe, and intelligent online SF6 purification technology, which can achieve the online detection and purification of SF6 micro-water and impurity gases when the high-voltage SF6 equipment is powered on and make the purification units’ renewable. Applying this technology can prevent the power cut of high-voltage power supply equipment, thereby making sure that the grids are safe. It is also environmentally friendly as it can reduce the usage of SF6 gas.