bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of substrate temperature on the dry zone generated by the vapor sink effect
Authors: Hu Jun , Zhao Haonan , Xu Zhen , Hong He , Wang Zhan-Long
Published: June 2024

Anti-condensation is important in various fields, e.g., transportation, power transmission, internal drying of precision instruments. Vapor sink is an important manner to suppress the happening of water vapor condensation, and shows potentials in some special scenarios. However, the mechanism of anti-condensation by vapor sink is not well understood up until now. In this article, the effect of substrate temperature on the dry zone generated by vapor sink were systematically studied with experiments and theoretical analysis. First, the effect of hygroscopic solutions on the local humidity were measured. The results indicated that the local humidity level near the hygroscopic solutions was effectively suppressed, reducing the water vapor condensation. Second, the variation of the dry zone with the cooling substrate temperature was systematically studied. The results indicated that the dry zone exhibits a hyperbolic relationship with the substrate temperature. The dry zone changing under different humidity conditions and cooling time were also studied. The dry zone remained approximately unchanged over time in a short period. Finally, a simple yet effective model between the dry zone and substrate temperature was deduced. The theoretical results are in good agreement with the experimental data. Our study may deeper the understanding of condensation suppression via vapor sink and offer guidance to the design of anti-condensation or anti-icing surfaces.
Orientation transitions and chiral assemblies of para-terphenyl molecules on Cd(0001)
Authors: Li Zuo , Yang Xiaotian , Wang Hao , Yao Gang , Tao Minlong , Sun Kai , Wang Junzhong
Published: June 2024

The interplay between orientation transition and chiral self-assemblies of para-terphenyl (P3P) molecules on the Cd(0001) surface has been investigated using low temperature scanning tunneling microscopy and density functional theory calculations. Three distinct molecular orientations have been discerned from the self-assembled thin films of P3P. At the low coverage, flat-lying molecules appear in the homochiral domains with the incommensurate registry to the substrate. With the coverage increasing, the incoming molecules are incorporated into the first layer with edge-on orientation and form the self-assembled zigzag chains. The alternative arrangement of zigzag chains with opposite chirality leads to the formation of a c(4 × 2) superstructure, in which the tilted molecules exhibit orientational frustration and fuzzy noises. The analysis of the tunneling spectra reveals that the electronic structure of P3P layers is contingent upon the hybridization between the electronic states of P3P molecules and the Cd(0001) surface. These results provide important insights into the interplay between orientational transition and chiral assembly of P3P molecules on metal substrates.
An innovative modification to the Menter shear-stress transport turbulence model employing the symbolic regression approach
Authors: Song Hanqi , Ma Mingze , Yi Chen , Shao Zhiyuan , Bai Ruijie , Yan Chao
Published: June 2024

Drawing from the non-equilibrium link between the production Pk and dissipation ε of turbulent kinetic energy (TKE), we advocate for the introduction of a limiter to modulate the TKE production term within the Menter shear-stress transport (SST) model. The original SST model is made more sensitive to the adverse pressure gradient (APG) by Bradshaw's assumption. Bradshaw's assumption introduces the equilibrium condition Pk/ε = 1 in most regions of the turbulent boundary layer. In the APG flows with Pk≫ε, the equilibrium condition suppresses the magnitude of TKE (k) within the boundary layer, resulting in an early separation problem. To address this issue, we employ the symbolic regression (SR) to scrutinize the physical correlation between Pk/ε and local turbulence parameters, obtaining an approximate function FSR that encapsulates the relationship between Pk/ε, Sk/ε, and y+ in the APG flow. Following its incorporation into the original SST model in the form of a limiter, the FSR evolves into the SST-Symbolic Regression Evolution model. The SST-SRE is then applied to four cases with APGs. The modification leads to an increase in the skin-friction coefficient Cf in the APGs region and causes a downstream shift in the separation location, improving the consistency with high-accuracy data and experimental results. It is demonstrated that this correction can improve the early separation problem in the Menter SST turbulence model.
Material screening for future diffusion barriers in Cu interconnects: Modeling of binary and ternary metal alloys and detailed analysis of their barrier performance
Authors: Wehring Bettina , Karakus Firat , Gerlich Lukas , Lilienthal-Uhlig Benjamin , Hecker Michael , Leyens Christoph
Published: June 2024

One of the challenges in the semiconductor industry is to find new barrier materials and copper (Cu) alternative solutions in interconnects. In this work, we focused to find alternative diffusion barrier materials. Different binary (CoMo, CoRu, CoTa, CoW, MoRu, RuTa, RuW) and ternary (CoMoTa, CoRuTa, MoRuTa) metal alloys were evaluated theoretically with the Miedema model to find the amorphous phase composition range. Afterward, thin films of the alloys with various compositions were deposited by magnetron sputtering and theoretical values were compared to the experimental results. From the experimental measurements, which included grazing incidence x-ray diffraction analysis and resistivity measurements, suitable binary and ternary alloys were chosen for diffusion analysis. By annealing thin film stacks at temperatures ranging from 500 to 675°C, diffusion was induced and detected by x-ray photoelectron spectroscopy depth profiles. Seventeen alloys were evaluated by their diffusion barrier effectiveness, and five of those, which include Ru60Ta40, Ru45W55, Mo47Ru53, Mo36Ru50Ta14, and Co40Mo35Ta25, showed excellent barrier properties against copper diffusion. Furthermore, all of the stated materials have a lower resistivity than TaN. Last, the adhesion of the best performing alloys to SiCOH and Cu was evaluated by the modified edge lift-off test. Only Ru45W55 had reasonable adhesion at both interfaces. The other materials showed low adhesion strength to Cu, which would make an adhesion promoter (liner), such as cobalt, necessary for the integration.
Rovibrational analysis of AlCO3, OAlO2, and HOAlO2 for possible atmospheric detection
Authors: Firth Rebecca A. , Palmer C. Zachary , Francisco Joseph S. , Fortenberry Ryan C.
Published: June 2024

The lack of observational data for the AlO molecule in the mesosphere/lower thermosphere may be due to ablated aluminum reacting quickly to form other species. Previously proposed reaction pathways show that aluminum could be ablated in the atmosphere from meteoritic activity, but there currently exist very limited spectroscopic data on the intermediates in these reactions, limiting the possible detection of said molecules. As such, rovibrational spectroscopic data are computed herein using quartic force field methodology at four different levels of theory for the neutral intermediates AlCO3, OAlO2, and HOAlO2. Each molecule exhibits multiple vibrational modes with large vibrational transition intensities. For instance, the C–O stretch (ν1) in AlCO3 has a harmonic intensity of 536 km mol−1, the Al–O stretch (ν2) in OAlO2 has an intensity of 678 km mol−1, and the out-of-plane torsion (ν9) in HOAlO2 has an intensity of 158 km mol−1. All three molecules have exceptionally large dipole moments of 6.27, 4.21, and 5.04 D, respectively. These properties indicate that all three molecules are good candidates for potential atmospheric observation utilizing vibrational and/or rotational spectroscopic techniques.
Numerical simulations of the optical properties of SiO2@Au core–shell nanoparticles: The effect of geometrical parameters on the tunability and sensitivity of their plasmon response
Authors: Al-Qadi Bassam
Published: June 2024

Based on systematic numerical simulations, the effect of geometrical parameters of SiO2@Au core-shells (nanoshells) on the tunability and sensitivity of their optical response was elucidated. The surface plasmon resonance (SPR) of nanoshells experiences a blueshift-redshift crossover with the increase in shell thickness, and this phenomenon is ascribed to the competition between the two effects, that is, the hybridization effect dominated in the thin shells and the retardation effect dominated in the thick shells. The relative strength of absorption/scattering in the extinction spectra and the relative strength of dipolar/multipolar modes can be selectively tuned by controlling the total volume of nanoshells. The sensitivity of the SPR peak wavelength to the shell thickness is primarily dependent on the core-to-shell ratio; the higher this ratio is, the larger the sensitivity. The tailorable properties of nanoshells make them promising and well-suited platforms in various applications.
Allosteric activation of VCP, an AAA unfoldase, by small molecule mimicry
Authors: Jones Natalie H. , Liu Qiwen , Urnavicius Linas , Dahan Noa E. , Vostal Lauren E. , Kapoor Tarun M.
Published: June 2024

The loss of function of AAA (ATPases associated with diverse cellular activities) mechanoenzymes has been linked to diseases, and small molecules that activate these proteins can be powerful tools to probe mechanisms and test therapeutic hypotheses. Unlike chemical inhibitors that can bind a single conformational state to block enzyme function, activator binding must be permissive to different conformational states needed for mechanochemistry. However, we do not know how AAA proteins can be activated by small molecules. Here, we focus on valosin-containing protein (VCP)/p97, an AAA unfoldase whose loss of function has been linked to protein aggregation-based disorders, to identify druggable sites for chemical activators. We identified VCP ATPase Activator 1 (VAA1), a compound that dose-dependently stimulates VCP ATPase activity up to ~threefold. Our cryo-EM studies resulted in structures (ranging from ~2.9 to 3.7 Å-resolution) of VCP in apo and ADP-bound states and revealed that VAA1 binds an allosteric pocket near the C-terminus in both states. Engineered mutations in the VAA1-binding site confer resistance to VAA1, and furthermore, modulate VCP activity. Mutation of a phenylalanine residue in the VCP C-terminal tail that can occupy the VAA1 binding site also stimulates ATPase activity, suggesting that VAA1 acts by mimicking this interaction. Together, our findings uncover a druggable allosteric site and a mechanism of enzyme regulation that can be tuned through small molecule mimicry.
English in the internationalization of higher education and international student mobility
Authors: Kurusu Kenichiro , Oda Chisato , Go Mikhail Alic C. , Wu Di , Saure Kevin Brandon , Narang Sakshi
Published: June 2024

In this article, we discuss the significance of English in the internationalization of higher education and
international student mobility, using Kachru’s (1985) Three Circles Model of World
English. As education is one of the major forms of migration (Liu-Farrer, 2022; Borlongan, 2023) in the so-called ‘age of migration’ (cf. de Haas, Castles, & Miller, 2020), more and more students are motivated to study abroad to complete
their tertiary education. First, we discuss motivating factors both for the internationalization of higher education and
international student mobility. Second, we point out how English has been playing a very central role in the internationalization
of higher education institutions and international student mobility (Philipson, 2010;
Jenkins, 2017) among these factors. Then, we present the dynamics of international
student mobility by looking at their global flow, English-medium programs, and English language proficiency requirements. While
Inner Circle countries are still the most attractive destinations for most international students, Expanding Circle countries,
where English is not an institutionalized medium of instruction in higher education, also value English by expanding
English-medium degree programs and requiring English proficiency test scores to admission. Finally, we end the article by
reiterating the dominance and utility of English in the internationalization of higher education and international student
mobility and its stable position as the language of educational migration.
Navigating through Transnational Experiences of Chinese Working Holiday Makers in New Zealand
Authors: Zhu Hongrui
Published: June 2024

In 2008, New Zealand took the lead globally in offering a working holiday scheme to Chinese youth following the Free Trade Agreement between the two countries. This scheme allows Chinese participants to live, work, and/or travel for 12 months in New Zealand, which attracted huge attention and sparked enormous interest among young Chinese. Against this backdrop, the primary focus of this case study is to examine the transnational experiences of Chinese working holiday makers (WHMs) in New Zealand through a cultural lens, highlighting the distinctive characteristics of this cohort. In particular, this case study explores the factors that motivated young Chinese to become WHMs in New Zealand. Moreover, this case sheds light on their dual-layered working experience; namely how they adapted to the positive working dynamics in New Zealand compared to the working experience back in China while still navigating through perceived precarious situations. This case further discusses how Chinese individuals have transformed their understanding of sociocultural norms and parental expectations through working holidays. Furthermore, the case study examines the broader economic impact of this growing cohort on New Zealand, providing insights into the implications of the working holiday scheme.

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Carboxyl-group compounds activate voltage-gated potassium channels via a distinct mechanism
Authors: Rönnelid Olle , Elinder Fredrik
Published: June 2024

Voltage-gated ion channels are responsible for the electrical excitability of neurons and cardiomyocytes. Thus, they are obvious targets for pharmaceuticals aimed to modulate excitability. Compounds activating voltage-gated potassium (KV) channels are expected to reduce excitability. To search for new KV-channel activators, we performed a high-throughput screen of 10,000 compounds on a specially designed Shaker KV channel. Here, we report on a large family of channel-activating compounds with a carboxyl (COOH) group as the common motif. The most potent COOH activators are lipophilic (4 < LogP <7) and are suggested to bind at the interface between the lipid bilayer and the channel’s positively charged voltage sensor. The negatively charged form of the COOH-group compounds is suggested to open the channel by electrostatically pulling the voltage sensor to an activated state. Several of the COOH-group compounds also activate the therapeutically important KV7.2/7.3 channel and can thus potentially be developed into antiseizure drugs. The COOH-group compounds identified in this study are suggested to act via the same site and mechanism of action as previously studied COOH-group compounds, such as polyunsaturated fatty acids and resin acids, but distinct from sites for several other types of potassium channel–activating compounds.
Isolated single-photon emitters with low Huang–Rhys factor in hexagonal boron nitride at room temperature
Authors: Bhunia Amit , Joshi Pragya , Singh Nitesh , Chakraborty Biswanath , Nair Rajesh V
Published: June 2024

The development of stable room-temperature bright single-photon emitters using atomic defects in hexagonal boron nitride flakes (h-BN) provides significant promise for quantum technologies. However, an outstanding challenge in h-BN is the creation and detection of isolated, stable single-photon emitters with high emission rates and with very low Huang–Rhys (HR) factor. Here, we discuss the quantum photonic properties of a single, isolated, stable quantum emitter that emits single photons with a high emission rate and a low HR value of 0.6 ± 0.2 at room temperature. A scanning confocal image confirms the presence of a deserted, single-quantum emitter with a prominent zero-phonon line at ∼578 nm with a well-separated phonon sideband at 626 nm. The second-order intensity-intensity correlation measurement shows an anti-bunching dip of ∼0.25 with an emission lifetime of 2.46 ± 0.1 ns, reinforcing distinct features of the single-photon emitter. The importance of low-energy electron beam irradiation and subsequent annealing is emphasized to achieve stable, reproducible single-photon emitters.
Dual-luminophore fast-responding pressure-sensitive paint for the simultaneous elimination of motion- and temperature-induced errors
Authors: Gu Feng , Wei Chunhua , Jiao Lingrui , Liu Yingzheng , Peng Di
Published: June 2024

Motion- and temperature-induced errors are the major sources of error in pressure-sensitive paint (PSP) measurement. In this study, we developed a novel dual-luminophore fast-responding PSP with reference and pressure-sensitive channels that have similar temperature sensitivities, enabling motion- and temperature-induced errors to be simultaneously eliminated by taking the intensity ratio of the two channels. Rhodamine B (RhB), which was loaded on the Mobil Composition of Matter No. 41 (MCM-41) molecular sieve, and platinum tetrakis (pentafluorophenyl) porphyrin (PtTFPP) were chosen as the reference and pressure-sensitive luminophores, respectively. These luminophores were mixed with mesoporous SiO2 particles and a small amount of polymer to form a sprayable motion–temperature cancellation (MTC) PSP. By controlling the concentration of RhB, the temperature sensitivity of the reference channel was adjusted to match that of PtTFPP. To minimize temperature-induced errors, the effect of spectral ranges was also investigated. The lowest temperature sensitivity achieved for the MTC-PSP was 0.025%/°C, yielding an extremely low temperature-induced error of 55 Pa °C−1. Its pressure sensitivity and response time were 0.46%/kPa and 145 μs, respectively. In addition, a theoretical model for the MTC-PSP that considers the effect of spectral overlap was proposed. The model accurately predicted the nonlinear relationship between the intensity ratio and pressure. The capability of the MTC-PSP was confirmed in a fast-rotating-disk experiment, and the pressure results agreed well with the theoretical pressure distribution on the disk.
The potential mechanisms and treatment effects of stem cell-derived exosomes in cardiac reengineering
Authors: Wang Yibin , Shi Xiulian
Published: June 2024

Exosomes are extracellular vesicles of diverse compositions that are secreted by numerous cell types. Exosomes contain significant bioactive components, including lipids, proteins, mRNA, and miRNA. Exosomes play an important role in regulating cellular signaling and trafficking under both normal physiological and pathological circumstances. A multitude of factors, including thermal stress, ribosomal stress, endoplasmic reticulum stress, and oxidative stress influence the concentrations of exosomal mRNA, miRNA, proteins, and lipids. It has been stated that exosomes derived from stem cells (SCs) modulate a range of stresses by preventing or fostering cell balance. Exosomes derived from SCs facilitate recovery by facilitating cross-cellular communication via the transmission of information in the form of proteins, lipids, and other components. For this reason, exosomes are used as biomarkers to diagnose a wide variety of diseases. The focus of this review is the bioengineering of artificial exosomal cargoes. This process encompasses the control and transportation of particular exosomal cargoes, including but not limited to small molecules, recombinant proteins, immune modulators, and therapeutic medications. Therapeutic approaches of this nature have the potential to deliver therapeutic medications precisely to the intended site for the cure of a variety of disorders. Notably, our attention has been directed towards the therapeutic implementations of exosomes derived from SCs in the cure of cardiovascular ailments, including but not limited to ischemic heart disease, myocardial infarction, sepsis, heart failure, cardiomyopathy, and cardiac fibrosis. In general, researchers employ two methodologies when it comes to exosomal bioengineering. This review aims to explain the function of exosomes derived from SCs in the regulation of stress and present a novel therapeutic approach for cardiovascular disorders.
Consistent spectral approximation of Koopman operators using resolvent compactification
Authors: Giannakis Dimitrios , Valva Claire
Published: June 2024

Koopman operators and transfer operators represent dynamical systems through their induced linear action on vector spaces of observables, enabling the use of operator-theoretic techniques to analyze nonlinear dynamics in state space. The extraction of approximate Koopman or transfer operator eigenfunctions (and the associated eigenvalues) from an unknown system is nontrivial, particularly if the system has mixed or continuous spectrum. In this paper, we describe a spectrally accurate approach to approximate the Koopman operator on L
2 for measure-preserving, continuous-time systems via a ‘compactification’ of the resolvent of the generator. This approach employs kernel integral operators to approximate the skew-adjoint Koopman generator by a family of skew-adjoint operators with compact resolvent, whose spectral measures converge in a suitable asymptotic limit, and whose eigenfunctions are approximately periodic. Moreover, we develop a data-driven formulation of our approach, utilizing data sampled on dynamical trajectories and associated dictionaries of kernel eigenfunctions for operator approximation. The data-driven scheme is shown to converge in the limit of large training data under natural assumptions on the dynamical system and observation modality. We explore applications of this technique to dynamical systems on tori with pure point spectra and the Lorenz 63 system as an example with mixing dynamics.
Oblique streaming waves observed in multipactor-induced plasma discharge above a dielectric surface
Authors: Jin Biemeng , Chen Jian , Sun Guangyu , Wang Zhibin , Sun Haomin
Published: June 2024

In a recent discovery (Wen et al 2022 Phys. Rev. Lett.
129 045001), streaming waves were found in multipactor-induced plasma discharges. However, due to the limitations of a 1D simulation setup, these waves displayed only transverse dynamics. In this letter, an extended 2D particle-in-cell/Monte Carlo model is used to simulate multipactor-induced plasma discharge above a dielectric surface. The results reveal that the streaming waves are not solely transverse but oblique, featuring both transverse and longitudinal components of the wave vector. Furthermore, it is identified that the sheath-accelerated field-emission electrons, rather than the previously reported secondary emission electrons, predominantly cause the excitation of streaming waves. The simulated wave spectrum achieves an excellent agreement with the theoretical dispersion relation. The identification of oblique streaming waves provides new insights into multipactor physics and is anticipated to inspire novel mitigation strategies for multipactor-induced breakdown processes.
Analyzing election trends incorporating memory effect through a fractional-order mathematical modeling
Authors: Santra P K , R Induchoodan , Mahapatra G S
Published: June 2024

This study proposes a new mathematical model to analyze and predict the results of a political election. In general, we predict or analyze the results using statistical methods; however, to minimize the effort of the study, we propose a fractional-order modeling approach. This study proposes a model to analyze and predict general election result trends in India, focusing on the state of West Bengal. To incorporate memory into the model, we consider the Caputo fractional derivative. The model solution’s positivity, boundedness, existence, and uniqueness were tested analytically. Numerical simulations were carried out to investigate the impact of the parameters and evaluate the model’s performance by incorporating the implications of the previous election for realistic situations. Following this, a qualitative analysis of the performance of political parties is discussed, and a prediction of the electoral victory is obtained.
New signature of low mass Z′ in J/ψ decays*
Authors: Geng 耿 Chao-Qiang 朝强 , Liu 劉 Chia-Wei 佳韋 , Zhang 张 Jiabao 嘉宝
Published: June 2024

We explored a new approach to search for a low-mass

particle through

decays by identifying its existence through parity-violating phenomena in the isospin-violating final states of

and the corresponding charge conjugated states of

. Our investigation centered on a generation-independent and leptophobic

with mass below 10 GeV. Given the present experimental conditions at Beijing Spectrometer III (BESIII) and the anticipated opportunities at the Super Tau Charm Factory (STCF), we conducted Monte-Carlo simulations to predict possible events at both facilities. Notably, we foresee a substantial enhancement in the precision of the lower limit estimation of

as well as a reduction in statistical uncertainty with upcoming STCF experiments. Furthermore, it is essential to highlight that a null result in the measurement of

would impose stringent constraints, requiring the

couplings to be in the order of

.
0– – hidden-heavy tetraquark states via QCD sum rules*
Authors: Wan 万 Bing-Dong 秉东 , Xu 徐 Hong-Tai 鸿泰
Published: June 2024

In this study, we evaluated the mass spectra of the prospective

hidden-charm and hidden-bottom tetraquark states in molecular configuration via QCD sum rules. In our calculation, the nonperturbative condensate contributions are considered up to dimension eight in operator product expansion. It is found that there could exist 4 possible

hidden-charm tetraquark states with masses

,

,

, and

GeV. Their corresponding hidden-bottom partners are found lying at

,

,

, and

GeV, respectively. The possible tetraquark decay modes were analyzed, which are expected to be measured in BESIII, BELLEII, and LHCb experiments.
Top-quark rare decays with flavor violation*
Authors: Liu 刘 Ming-Yue 明月 , Zhao 赵 Shu-Min 树民 , Gao 高 Song 松 , Han 韩 Xing-Yu 星宇 , Feng 冯 Tai-Fu 太傅
Published: June 2024

In the present study, we investigated the decays of the top quark:

,

,

, and

. They are extremely rare processes in the standard model (SM). As the

extension of the minimal supersymmetric standard model (MSSM), the

SSM features new superfields such as the right-handed neutrinos and three Higgs singlets. We analyzed the effects of different sensitive parameters on the results and made reasonable theoretical predictions, thereby providing a useful reference for future experimental development. Considering the constraint set by the updated experimental data, the numerical results show that the branching ratios of the four processes, i.e.,

, can reach the same order of magnitude as their experimental upper limits. Among them,

has the most evident effect on these processes and is the main parameter;

,

,

,

,

,

, and

are also important parameters for the processes, and have effects on the numerical results.
Robust adaptive deep brain stimulation control of in-silico non-stationary Parkinsonian neural oscillatory dynamics
Authors: Fang Hao , Berman Stephen A , Wang Yueming , Yang Yuxiao
Published: June 2024

Objective. Closed-loop deep brain stimulation (DBS) is a promising therapy for Parkinson’s disease (PD) that works by adjusting DBS patterns in real time from the guidance of feedback neural activity. Current closed-loop DBS mainly uses threshold-crossing on-off controllers or linear time-invariant (LTI) controllers to regulate the basal ganglia (BG) Parkinsonian beta band oscillation power. However, the critical cortex-BG-thalamus network dynamics underlying PD are nonlinear, non-stationary, and noisy, hindering accurate and robust control of Parkinsonian neural oscillatory dynamics. Approach. Here, we develop a new robust adaptive closed-loop DBS method for regulating the Parkinsonian beta oscillatory dynamics of the cortex-BG-thalamus network. We first build an adaptive state-space model to quantify the dynamic, nonlinear, and non-stationary neural activity. We then construct an adaptive estimator to track the nonlinearity and non-stationarity in real time. We next design a robust controller to automatically determine the DBS frequency based on the estimated Parkinsonian neural state while reducing the system’s sensitivity to high-frequency noise. We adopt and tune a biophysical cortex-BG-thalamus network model as an in-silico simulation testbed to generate nonlinear and non-stationary Parkinsonian neural dynamics for evaluating DBS methods. Main results. We find that under different nonlinear and non-stationary neural dynamics, our robust adaptive DBS method achieved accurate regulation of the BG Parkinsonian beta band oscillation power with small control error, bias, and deviation. Moreover, the accurate regulation generalizes across different therapeutic targets and consistently outperforms current on-off and LTI DBS methods. Significance. These results have implications for future designs of closed-loop DBS systems to treat PD.
Prediction of transport in the JET DTE2 discharges with TGLF and NEO models using the TGYRO transport code
Authors: Shi N. , Staebler G.M. , Belli E.A. , McClenaghan J. , Kim H-T. , Auriemma F. , Kirov K. , Frigione D. , Garzotti L. , Zotta V.K. , Rimini F. , Van Eester D. , Lomas P. ,   JET Contributors
Published: June 2024

The JET Deuterium-Tritium-Experiment Campaign 2 (DTE2) has demonstrated the highest-ever fusion energy production. To forecast the transport dynamics within these discharges, the TGLF and NEO models within the TGYRO transport code were employed. A critical development in this study is the new quasilinear transport model, TGLF-SAT2, specifically designed to resolve discrepancies identified in JET deuterium discharges. This model accurately describes the saturated three-dimensional (3D) fluctuation spectrum, aligning closely with a database of nonlinear CGYRO turbulence simulations, thereby enhancing the predictive accuracy of TGYRO simulations. In validating against the JET DTE2 discharges across two primary operating scenarios, TGYRO effectively predicted the temperature profiles within a broad radial window (ρ ∼ 0.2–0.85), though with minor ion temperature discrepancies near the core. However, a consistent underprediction of electron density profiles by 20% across the simulation domain was noted, indicating areas for future refinement. To achieve a self-consistent steady-state solution based on the JET DTE2 discharges, an integrated modeling workflow TGYRO-STEP within the OMFIT framework was introduced. This workflow iterates among the core transport, the pedestal pressure and the MHD equilibrium, ultimately yielding a converged solution that significantly reduces dependence on experimental boundary conditions for temperature and density profiles. The integrated simulation results show negligible differences in electron density and temperature profiles compared to standalone TGYRO modeling, while the ion temperature profile is lower due to the updated boundary condition in TGYRO-STEP. The application of the TGYRO-STEP workflow to JET DTE2 discharges serves as a crucial test to validate its robustness and highlights its limitations, providing valuable insights for its potential future application in ITER and Fusion Power Plant deuterium and tritium prediction modeling.
Material characterization by surface wave parameters extraction using 3D vibrometer and ellipsometry
Authors: Bouzzit A. , Arciniegas A. , Martinez L. , Serfaty S. , Wilkie-Chancellier N.
Published: June 2024

This work focuses on the monitoring of the 3D propagation of ultrasonic surface waves used in non-destructive testing and evaluation. The ellipticity of the movement related to the Rayleigh wave, specifically the H/V parameter, is studied analytically, numerically, and experimentally on an aluminum block. The study involves generating signals from the theoretical harmonic expression of particle displacement issued from Rayleigh wave, carrying out numerical simulations using a finite element method, and generating the Rayleigh wave using a shear contact transducer with a 1 MHz central frequency in the experimental study. The work also involves appropriate filtering of signals to extract components with specific polarization and suppress other modes with low polarization energy. The obtained results for aluminum show a good agreement between the analytical, numerical, and experimental studies of Rayleigh wave ellipticity. Moreover, these H/V ratios are consistent with the theoretical values described in the literature. As a proof of concept, this method is also applied to simulation data to study orthotropic materials (wood/bone), obtaining promising results.
Towards an understanding of the mechanisms of therapeutic ultrasound on biomimetic models of cancer
Authors: Silva D J D C , Cheema U , Gélat P
Published: June 2024

Therapeutic ultrasound is transforming the treatment of a range of malignancies in a non-invasive and non-systemic manner. Low-intensity ultrasound (LIUS) has been proposed to selectively eradicate cancer cells but the underlying biological mechanisms remains unknown. To gain an understanding of this phenomenon, 2D breast cancer monocultures were sonicated at varying acoustic intensities (0.1–0.5 W·cm−2) and excitation times (1–10 minutes). Additionally, 2D monocultures consisting of healthy cell lines were sonicated at varying acoustic intensities (0.1–0.5 W·cm−2) to determine any distinguishing biological responses. To begin recapitulating in vivo conditions, breast cancer cells were also seeded into 3D collagen hydrogels. At a 1 MHz frequency, 20% duty cycle, 100 Hz pulse repetition frequency, a significant drop in cancer cell viability is observed at a sonication intensity of 0.5 W·cm−2 and over 10 minute excitation time. Healthy counterparts subjected to the same parameters revealed no distinguishing effects. Sonication of breast cancer cells seeded in 3D collagen hydrogels revealed no effect in cell viability compared to non-sonicated controls. The acoustic wave propagation software OptimUS was used to determine the influence culturing plates have on ultrasound propagation, revealing these materials can significantly vary the acoustic field at frequencies relevant to LIUS.
Improved skull bone acoustic property homogenization for fast transcranial ultrasound simulations
Authors: Angla Célestine , Larrat Benoit , Gennisson Jean-Luc , Chatillon Sylvain
Published: June 2024

Transcranial ultrasound simulations are crucial to optimize and secure ultrasound interventions in brain therapy, depending on the patient skull. When performing such simulations, accurate modeling of the skull is essential, although very challenging, because of the inter/intra sample property variability. Simulations based on semi-analytical methods require a homogeneous description of the skull. Averaging the acoustic property maps derived from the CT scan does not modify the focus shift, but it leads to an overestimation of the pressure field amplitude. The purpose of this work is to provide a homogenization method that compensates for this amplitude overestimation. First, the skull acoustic property maps are segmented into a three-layer medium to represent the different types of skull bone (cortical – trabecular – cortical). Then, equivalent properties are computed so as to minimize the time of flight and transmission coefficient errors between the three-layer medium and the one-layer equivalent medium. This method was validated using 3D simulations with CIVA Healthcare and k-Wave and has proven to be very efficient.
Evaluation of the benefits of tradable peak energy use rights products
Authors: Zhao Haibo , Zhang Zhi , Wang Yao , Wang He , Wang Huaqing , Tan Zhongfu
Published: June 2024

Environmental degradation and energy security issues require our country to accelerate the transition of its energy consumption structure towards decarbonization. Clarifying the impact of the pilot trading system of peak energy use rights products on the low-carbon transformation of energy consumption structure and the path of its effect is an important policy revelation for the construction of market-based environmental rights and interests regulation. In this paper, we study the implementation effect of the pilot provinces of peak energy use right product trading from the perspective of carbon emission reduction benefit and analyze the carbon emission reduction benefit generated by the peak energy use right product according to the pilot trading situation.
Study on the carbon footprint impact analysis method of integrated energy system operation in low-carbon park considering multi-domain dynamic characteristics
Authors: Wang Yang , Qiao Biao , Tan Zhukui , Sun Zongyu , Fu Yu , Liang Shukui , Li Yue
Published: June 2024

Low-carbon parks are an important battlefield for China to achieve the goal of peaking carbon neutrality. Accurate and efficient analysis and tracking of park carbon footprint is a necessary measure to reduce carbon and save energy in parks. Aiming at the problems of less research on the carbon footprint of low-carbon parks at home and abroad and the lack of tracking and analysis methods of dynamic influencing factors of carbon footprint, this paper focuses on the carbon footprint of typical low-carbon parks during operation and proposes a dynamic tracking method of the carbon footprint of low-carbon parks that considers the dynamic characteristics of carbon emissions in various fields. In this paper, the hierarchical impact structure of the carbon footprint of low-carbon parks was first constructed, including the impact of population, economy, construction, energy, transportation, and industry. LMDI (Logarithmic Mean Divisia Index) was used to decompose the macro-level impact of the carbon footprint of low-carbon parks. Secondly, this paper establishes a dynamic simulation model of carbon emissions of low-carbon parks in the fields of building, energy, transportation, and industry, which can realize 8760 hours of dynamic simulation calculation throughout the year. Based on dynamic simulation, this paper carries out single factor sensitivity analysis and combines the Monte Carlo simulation method to complete quantitative calculation of dynamic second-order influence weight of carbon footprint. Finally, a multi-domain impact analysis and tracking method for the carbon footprint of low-carbon parks is obtained.
Study on optimal scheduling of energy storage participation in power market considering source-load uncertainty
Authors: Zhang Weijun , Guo Wei , Huang Jinfu , Chen Dawei , Deng Chaoping
Published: June 2024

With the increasing penetration of new energy sources such as wind and light in the power grid, the selection of new energy-storage joint scheduling and operation methods can reduce the phenomenon of wind and light abandonment, but the new energy-storage joint scheduling and operation methods need to take into account the market factors, characteristics, and other aspects of a variety of problems. Given these difficulties, this paper takes into account the uncertainty of wind power, adopts the Latin hypercube sampling method to generate and consider the probabilistic distance fast reduction method, selects the typical scenarios, establishes the energy storage market operation model by minimizing the comprehensive operation cost, and responds to the source-load demand through the integrated response of the energy storage and the power grid. Finally, the effectiveness of the proposed method is demonstrated through simulation examples.
Design of maximum power point energy storage and inverter for photovoltaic power generation
Authors: Fan Yaohua , Chen Jianli , Bian Qingqing , Wu Yuzhen , Tong Jie , Zhan Chunyi
Published: June 2024

With the increasing tension of fossil energy in the world and the damage to the environment caused by the use of fossil energy, new energy led by solar energy has been paid much more attention by countries around the world. If the efficiency of solar energy is improved, it will bring breakthrough changes to the world’s energy structure. Based on the related applications of solar photovoltaic power generation, this paper designs an independent photovoltaic power generation system with energy storage device. In the form of DC/DC conversion, the system uses the maximum power point tracking technology of photovoltaic cells to realize the efficient use of solar energy during the charging process. The system inverts the DC voltage after the storage, realizing the transformation of DC voltage to 220 V AC voltage, to realize the utilization of energy in various aspects.
Soft coal drilling technology and application based on air directional drilling
Authors: Song Yubo
Published: June 2024

In China, there are many layers and a wide distribution of crushed soft coal seams, which are commonly characterized by complex structural stress, high gas pressure, and low mechanical strength of coal bodies. In response to the problems of hole collapse and spray during the drilling process of such coal seams, such as hole wall instability, drilling difficulties, and the existence of blind spots for extraction, a dual tube and dual action air directional drilling method was proposed for coal mine soft and fractured coal seams. The grading of protective casing and inner tube directional drilling tools was studied, the parameters of spiral casing blades were optimized, and air supply parameters such as air volume and pressure were studied. Numerical simulation and on-site testing methods were used to study the law of powder discharge and the optimal drilling process parameters. Research and field experiments have shown that the construction depth of dual pipe and dual action drilling can reach over 300 meters, effectively improving the hole formation rate and drilling construction accuracy and providing a new process method for precise drilling of deep holes while drilling in fragmented soft coal seams.
Multi-Task neural network model considering low power output risk for short-term photovoltaic forecasting
Authors: Song Weiye , Jiao Meining , Han Shuang , Yan Jie , Wang Han , Liu Yongqian
Published: June 2024

As the proportion of installed photovoltaic power generation continues to increase, low output under the influence of large-scale weather systems has an increasingly significant influence on the power grid. There is an urgent need to improve photovoltaic power generation forecasting accuracy and reduce the risk of insufficient output in forecast results. To this end, a multi-task neural network model considering low power output risk (LPOMTN) for short-term photovoltaic forecasting is proposed. First, a numerical weather forecast encoder based on multi-scale CNN-Attention is established, which can extract multi-time scale photovoltaic output characteristics. Then a low-output day prediction module based on parallel CNN decoding and a photovoltaic low-output process prediction module based on the clear-sky model and LSTM were established. The latter uses the prediction results of the former as input, and the two modules perform training modeling in a multi-task learning manner to strengthen the model’s sensitivity to low-output states and improve the accuracy of low-output process predictions. The calculation example results show that LPOMTN has higher average forecasting accuracy for power output processes compared to methods such as XGBoost.
Performance prediction of a novel solar power tower system based on spectral beam splitting
Authors: Zhang Miaomiao , Qiu Zhongzhu , Zhang Jingkui , Zhu Qunzhi , Zhang Tao , Cai Jingyong , Ni Xingrui , Xu Ning , Huang Qinqing , Liao Chenqi
Published: June 2024

Photovoltaic technology is currently the most widely used solar generation technology in engineering. The particular spectral response band of PV cells cannot convert all solar radiation into electricity. Meanwhile, some radiation will become heat, leading to an increase in cell temperature and a decrease in the conversion efficiency of photovoltaic cells. Spectral splitting technology is an effective technology to improve electrical generation efficiency and can achieve full spectrum utilization of solar energy. The current work involved (1) proposing a novel solar power tower comprehensive utilization system based on spectral splitting; (2) developing a spectral splitting thin film configuration by using the Needle method whose transmittance is higher than 90% against the band range of 510 nm-1, 020 nm; (3) setting up a spectral splitting PV panel whose cover glass is coated the developed film, and replacing the heliostat of SPT system by using such spectral splitting PV panels; (4) predicting the electrical power generation of the spectral splitting-based tower type concentrating solar power system. The results demonstrate that the power generation efficiency of the proposed system is 5.5% and 3.46% higher than PV power generation and SPT systems respectively.
Harmonic impedance estimation based on improved rank estimation
Authors: Wang Dianlang , Chen Jing , Yin Qi , Ding Hanlin , Liu Qingsong , Miao Hong
Published: June 2024

In response to the issue of harmonic data anomalies affecting harmonic impedance estimation, a method based on improved rank regression is proposed, building upon the foundation of rank estimation. This method utilizes harmonic data sampled from the point of common coupling, treating harmonic impedance as regression parameters. Initially, the least squares method is employed to solve for regression parameters. Subsequently, Bayesian optimization is applied to refine these parameters. The optimized parameters are then incorporated into the rank estimation function derived from the residual rank matrix for weighted iteration. The final calculation results are determined through this iterative process. Simulation analysis demonstrates that this method can effectively mitigate the impact of outliers, yielding more accurate harmonic impedance values.
The design of the insulation layer and energy consumption optimization of the injection mould for the motor commutator
Authors: Wang Yuhui , Han Lei
Published: June 2024

The injection molding of the motor commutator requires a long-term high-temperature operation, which poses a problem of high energy consumption. The heating zone is located behind the mold, and there is thermal radiation and convection during heating, resulting in uneven temperature distribution. To solve the above problems, an automatic lifting and insulation mechanism is proposed. An insulation frame is built with an aerogel insulation layer inside. It is connected up to the upper table of the machine, moving up and down during processing, and connected down to the crank slider mechanism. Simulation software analyzes its insulation and temperature distribution and, through experimental verification, compares the temperature distribution and energy consumption of injection molds before and after the installation of insulation mechanisms. The experimental and simulation results show that using the automatic lifting insulation layer design scheme can effectively reduce energy consumption, improve temperature distribution unevenness, and increase the yield rate.