bluuebunny/crossref_metadata_2025 huggingface dataset:
Relative alignment between gas structures and magnetic field in Orion A at different scales using different molecular gas tracers
Authors: Jiao Wenyu , Wang Ke , Xu Fengwei , Wang Chao , Beuther Henrik
Published: March 2024

Context. Magnetic fields can play a crucial role in high-mass star formation. Nonetheless, the significance of magnetic fields at various scales and their relationship with gas structures have been largely overlooked.

Aims. Our goal is to examine the relationship between the magnetic field and molecular gas structures within the Orion A giant molecular cloud at different scales and density regimes.

Methods. We assessed the gas intensity structures and column densities in Orion A using 12CO, 13CO, and C18O from Nobeyama observations. By comparing Nobeyama observations with Planck polarization observations on large scales (~0.6 pc) and JCMT polarization observations on small scales (~0.04 pc), we investigate how the role of magnetic fields changes with scale and density.

Results. We find a similar trend from parallel to perpendicular alignment with increasing column density in Orion A at both large and small spatial scales. In addition, when changing from low-density to high-density tracers, the relative orientation preference changes from random to perpendicular. The self-similar results at different scales indicate that magnetic fields are dynamically important in both cloud formation and filament formation. However, magnetic field properties at small scales are relative complicated, and the interplay between magnetic field and star-forming activity needs to be discussed case by case.
Formation of long-period post-common envelope binaries
Authors: Belloni Diogo , Zorotovic Monica , Schreiber Matthias R. , Parsons Steven G. , Moe Maxwell , Garbutt James A.
Published: March 2024

Context. It has been claimed for more than a decade that energies other than orbital and thermodynamic internal are required to explain post-common envelope (CE) binaries with sufficiently long orbital periods (≳1 d) hosting AFGK-type main-sequence stars (∼0.5 − 2.0 M⊙) paired with oxygen-neon white dwarfs (≳1.1 M⊙). This would imply a completely different energy budget during CE evolution for these post-CE binaries in comparison to the remaining systems hosting M dwarfs and/or less massive white dwarfs.

Aims. In this first in a series of papers related to long-period post-CE binaries, we investigated whether extra energy is required to explain the currently known post-CE binaries with sufficiently long orbital periods consisting of oxygen-neon white dwarfs with AFGK-type main-sequence star companions.

Methods. We carried out binary population simulations with the BSE code adopting empirically derived inter-correlated main-sequence binary distributions for the initial binary population and assuming that the only energy, in addition to orbital, that help to unbind the CE is thermal energy. We also searched for the formation pathways of the currently known systems from the zero-age main-sequence binary to their present-day observed properties.

Results. Unlike what has been claimed for a long time, we show that all such post-CE binaries can be explained by assuming inefficient CE evolution, which is consistent with results achieved for the remaining post-CE binaries. There is therefore no need for an extra energy source. We also found that for CE efficiency close to 100%, post-CE binaries hosting oxygen-neon white dwarfs with orbital periods as long as one thousand days can be explained. For all known systems we found formation pathways consisting of CE evolution triggered when a highly evolved (i.e. when the envelope mass is comparable to the core mass), thermally pulsing, asymptotic giant branch star fills its Roche lobe at an orbital period of several thousand days. Due to the sufficiently low envelope mass and sufficiently long orbital period, the resulting post-CE orbital period can easily be several tens of days.

Conclusions. We conclude that the known post-CE binaries with oxygen-neon white dwarfs and AFGK-type main-sequence stars can be explained without invoking any energy source other than orbital and thermal energy. Our results strengthen the idea that the most common formation pathway of the overall population of post-CE binaries hosting white dwarfs is through inefficient CE evolution.
An individual-based model to predict the spatial distribution of northern pike, European perch and pikeperch from habitat use in a reservoir subject to water level fluctuations
Authors: Miguet Paul , Tissot Laurence , Lambert Patrick , Pauwels Ine S. , Westrelin Samuel
Published: March 2024

Reservoirs are subject to artificial water level fluctuations leading to a degradation of the littoral habitats. This often results in reduced productivity and biological diversity, particularly for fish. The development of predictive tools of fish population dynamics linked to habitat characteristics can help to optimize management actions such as habitat restoration. We developed a spatially explicit individual-based model, the 3Plake model, which predicts the spatial distribution of three fish species, northern pike, European perch and pikeperch, over seasons and diel cycles according to their habitat use. The model was calibrated with an accurate description of habitat and high spatial and temporal resolution data of fish movements in a French reservoir. The model calibration is only based on a species-specific coefficient of habitat selectivity. It was chosen to (i) match the observed and simulated traveled hourly and daily distances and (ii) minimize a metric quantifying the distance between observed and simulated density maps. The 3Plake model correctly simulated the means of traveled distances and the species distributions along the year on the study reservoir. The minimal input required (HSI maps and maximum distance range) allows its easy implementation on other reservoirs and fish species. It could be used to assess the impact of habitat restoration or water level management scenarios on fish distribution.
Reliable uncertainties of tests and surveys – a data-driven approach
Authors: Chakrabartty Satyendra Nath , Kangrui Wang , Chakrabarty Dalia
Published: March 2024

Policy decisions are often motivated by results attained by a cohort of responders to a survey or a test. However, erroneous identification of the reliability or the complimentary uncertainty of the test/survey instrument, will distort the data that such policy decisions are based upon. Thus, robust learning of the uncertainty of such an instrument is sought. This uncertainty is parametrised by the departure from reproducibility of the data comprising responses to questions of this instrument, given the responders. Such departure is best modelled using the distance between the data on responses to questions that comprise the two similar subtests that the given test/survey can be split into. The paper presents three fast and robust ways for learning the optimal-subtests that a given test/survey instrument can be spilt into, to allow for reliable uncertainty of the given instrument, where the response to a question is either binary, or categorical − taking values at multiple levels − and the test/survey instrument is realistically heterogeneous in the correlation structure of the questions (or items); prone to measuring multiple traits; and built of small to a very large number of items. Our methods work in the presence of such messiness of real tests and surveys that typically violate applicability of conventional methods. We illustrate our new methods, by computing uncertainty of three real tests and surveys that are large to very-large in size, subsequent to learning the optimal subtests.
An improved sequential insertion algorithm and tabu search to vehicle routing problem with time windows
Authors: Yue Bin , Yang Jie , Ma Junxu , Shi Jinfa , Shangguan Linjian
Published: March 2024

The vehicle routing problem (VRP) is a well-researched problem in the operations re- search literature. This paper studies a vehicle routing problem with time windows. Based on Solomon’s research, an improved sequential initialization algorithm, Solomon i1 with DTWC (Solomon i1 with Dynamic Time Windows Compatibility), is proposed in this paper to construct feasible initial solutions with higher quality in less calculation time. A tabu search with VNS (Variable Neighborhood Search) and the Metropolis criterion is used to further optimize the solutions that the proposed initialization algorithm provides. We run computational experiments on cases of well-known problems. Results show that compared to the initialization method before the change, our improved initialization approach performs well in terms of providing a better feasible initialization solution in less time, with an average 10% improvement in solution quality and an average 34% computational time savings. The proposed initialization algorithm’s superiority is also demonstrated by the tabu search’s better performance on the initial solutions it produces.
Évaluation des effets d’une formation à l’intervention éducative brève en contexte d’urgence bucco-dentaire chez des étudiants chirurgiens-dentistes
Authors: Rodriguez-Perron Isabelle , Azogui-Levy Sylvie , De Andrade Vincent , Gagnayre Rémi , Margat Aurore
Published: March 2024

Introduction : L’appropriation des messages destinés aux patients lors d’une consultation aux urgences bucco-dentaires est primordiale. Pour l’améliorer, la formation des futurs professionnels de santé à l’Éducation Thérapeutique du Patient précédant la sortie d’hospitalisation (ETP-sh) et aux principes de littératie en santé, semble essentielle. L’objectif de cette étude est d’évaluer les effets d’une formation à l’intervention éducative brève (type ETP-sh) en contexte d’urgence, menée auprès d’étudiants en 6ème année d’études odontologiques. Méthode : Il s’agit d’évaluer la satisfaction et l’effet sur le sentiment de compétence des participants (étudiants en dernière année d’études odontologiques) à une formation à l’ETP-sh en contexte d’urgence bucco-dentaire, par une étude descriptive, analytique, avant/après intervention. Résultats : Dix-huit étudiants ont été inclus (sur 48 soit, 37,5 % de taux de participation) dont, selon un questionnaire auto-administré, 94 % ont déclaré être satisfaits des objectifs et méthodes de la formation. L’évaluation des scores de sentiment de compétence montre une augmentation significative après la formation. (Pré : 1,2 ± 0,071 ; Post : 1,9 ± 0,063 ; p < 0,05). Discussion : Les bénéfices des formations à ce type d’intervention ont été montrés pour les participants dans différents milieux professionnels. Les relations entre les interventions en littératie en santé et ETP et l’intérêt de développer un modèle pédagogique spécifique a été montré, notre démarche s’inscrit dans cette idée et devrait être développée plus avant pour y participer. Ce qui s’inscrirait aussi dans la volonté de diminuer les inégalités sociales de santé et leurs rapports avec l’ETP. Conclusion : L’inclusion d’une formation aux interventions éducatives brèves dans le cursus de formation initiale des étudiants en odontologie serait bénéfique pour les participants, en termes de relation soignant-soigné, de confiance en leurs capacités et au-delà, pour la qualité de soins des établissements.
L’entretien motivationnel. Son histoire, son évolution et ses liens avec l’éducation thérapeutique du patient
Authors: Gache Pascal , Sommer Johanna
Published: March 2024

Changer de comportement pour améliorer sa santé est devenu un enjeu de santé publique. L’entretien motivationnel (EM) est une approche relationnelle issue de la psychologie rogérienne et éprouvée scientifiquement. Son but est d’augmenter la motivation des patients à engager un changement utile à leur santé. L’EM a montré son efficacité dans de nombreux domaines tels que les addictions, les maladies chroniques, le monde pénitentiaire, la pédagogie ou encore les performances sportives. Sa pratique requiert une expertise elle-même initiée par une formation spécifique. L’EM a de nombreuses similarités avec l’éducation thérapeutique du patient (ETP) non seulement dans ses fondements théoriques mais également dans sa pratique. Empathie, renforcement de l’autonomie, regard positif sur les compétences et le devenir des patients, espoir partagé… appartiennent aussi bien à l’EM qu’à l’ETP. Ainsi, EM et ETP sont complémentaires et permettent, lorsqu’ils sont pratiqués en commun, d’améliorer l’efficacité des programmes d’ETP notamment en augmentant la motivation des patients à s’engager et à perdurer dans ces programmes. Des formations conjointes en EM et ETP devraient être utilement proposées aux soignants garantissant aux patients une prise en charge optimale de leurs difficultés dans une collaboration efficace.
Fabrication of ZnSnO3 single crystal films on sapphire substrates by pulsed laser deposition for solar-blind photodetectors
Authors: Zhu Hongyan , Chen Rongrong , Han Xinyu , Wang Yuankang , Luan Caina , Ma Jin , Xiao Hongdi
Published: March 2024

ZnSnO3 single crystal films were prepared on c-plane sapphire substrates using pulsed laser deposition and post-annealing methods. For the as-grown sample at 700 °C, post-annealing at 700 °C resulted in a significant improvement in the crystalline quality of the single crystal films, while post-annealing at 800 °C led to decomposition of ZnSnO3. Compared with the amorphous and mixed crystal ZnSnO3-based photodetectors (PDs), the single crystal ZnSnO3-based PD has a better light-to-dark current ratio (1.32 × 106) and higher responsivity (8.71 A/W) at 5 V under 254-nm UV (1.1 mW/cm2) illumination. Such a good performance serves as resounding validation of the remarkable potential of ZnSnO3 epitaxial films in the context of solar-blind PDs.
Effect of air-loading on the performance limits of graphene microphones
Authors: Pezone R. , Baglioni G. , van Ruiten C. , Anzinger S. , Wasisto H. S. , Sarro P. M. , Steeneken P. G. , Vollebregt S.
Published: March 2024

As a consequence of their high strength, small thickness, and high flexibility, ultrathin graphene membranes show great potential for pressure and sound sensing applications. This study investigates the performance of multi-layer graphene membranes for microphone applications in the presence of air-loading. Since microphones need a flatband response over the full audible bandwidth, they require a sufficiently high mechanical resonance frequency. Reducing membrane thickness facilitates meeting this bandwidth requirement, and therefore, also allows increasing compliance and sensitivity of the membranes. However, at atmospheric pressure, air-loading effects can increase the effective mass, and thus, reduce the bandwidth of graphene and other 2D material-based microphones. To assess the severity of this performance-limiting effect, we characterize the acoustic response of multi-layer graphene membranes with a thickness of 8 nm in the pressure range from 30 to 1000 mbar, in air and helium environments. A bandwidth reduction by a factor ∼2.8× for membranes with a diameter of 500 μm is observed. These measurements show that air-loading effects, which are usually negligible in conventional microphones, can lead to a substantial bandwidth reduction in ultrathin graphene microphones. With analytical and finite element models, we further analyze the performance limits of graphene microphones in the presence of air-loading effects.
Tapered chiral nanoparticles as broad-spectrum thermally stable antivirals for SARS-CoV-2 variants
Authors: Gao Rui , Xu Xinxin , Kumar Prashant , Liu Ye , Zhang Hongyu , Guo Xiao , Sun Maozhong , Colombari Felippe Mariano , de Moura André F. , Hao Changlong , Ma Jessica , Turali Emre Emine Sumeyra , Cha Minjeong , Xu Liguang , Kuang Hua , Kotov Nicholas A. , Xu Chuanlai
Published: March 2024

The incessant mutations of viruses, variable immune responses, and likely emergence of new viral threats necessitate multiple approaches to novel antiviral therapeutics. Furthermore, the new antiviral agents should have broad-spectrum activity and be environmentally stable. Here, we show that biocompatible tapered CuS nanoparticles (NPs) efficiently agglutinate coronaviruses with binding affinity dependent on the chirality of surface ligands and particle shape.
L-
penicillamine-stabilized NPs with left-handed curved apexes display half-maximal inhibitory concentrations (IC
50
) as low as 0.66 pM (1.4 ng/mL) and 0.57 pM (1.2 ng/mL) for pseudo-type SARS-CoV-2 viruses and wild-type Wuhan-1 SARS-CoV-2 viruses, respectively, which are about 1,100 times lower than those for antibodies (0.73 nM). Benefiting from strong NPs–protein interactions, the same particles are also effective against other strains of coronaviruses, such as HCoV-HKU1, HCoV-OC43, HCoV-NL63, and SARS-CoV-2 Omicron variants with IC
50
values below 10 pM (21.8 ng/mL). Considering rapid response to outbreaks, exposure to elevated temperatures causes no change in the antiviral activity of NPs while antibodies are completely deactivated. Testing in mice indicates that the chirality-optimized NPs can serve as thermally stable analogs of antiviral biologics complementing the current spectrum of treatments.
Elucidating the behavior of the SARS-CoV-2 virus surface at vapor–liquid interfaces using molecular dynamics simulation
Authors: Fleckenstein Florian , Stephan Simon , Hasse Hans
Published: March 2024

Aerosols play a major role in the transmission of the SARS-CoV-2 virus. The behavior of the virus within aerosols is therefore of fundamental importance. On the surface of a SARS-CoV-2 virus, there are about 40 spike proteins, which each have a length of about 20 nm. They are glycosylated trimers, which are highly flexible, due to their structure. These spike proteins play a central role in the intrusion of the virus into human host cells and are, therefore, a focus of vaccine development. In this work, we have studied the behavior of spike proteins of the SARS-CoV-2 virus in the presence of a vapor–liquid interface by molecular dynamics (MD) simulations. Systematically, the behavior of the spike protein at different distances to a vapor–liquid interface were studied. The results reveal that the spike protein of the SARS-CoV-2 virus is repelled from the vapor–liquid interface and has a strong affinity to stay inside the bulk liquid phase. Therefore, the spike protein bends when a vapor–liquid interface approaches the top of the protein. This has important consequences for understanding the behavior of the virus during the dry-out of aerosol droplets.
Ethics and Food Scientists: Duties, Issues and Dilemmas
Authors: Early Ralph
Published: March 2024

Food scientists, as food industry professionals employed by the diversity of food businesses that collectively define food systems, possess moral agency. They have the potential to act for the moral good or the moral evil and should always advocate for the moral good. Codes of professional conduct for the profession of food scientist published by professional bodies representing food scientists and food technologists (henceforth referred to exclusively as food scientists) express standards of behaviour and aspects of ethical conduct required of those who follow such careers. By their advisory nature, the codes are understandably restricted in scope. Moral issues may originate within food businesses or arise externally due to other factors (e.g. government policy making). Codes of professional conduct cannot be expected to encompass concepts in moral philosophy or explain methods of assessing and dealing with moral issues. The purpose of this case study is to invite students to explore concepts in moral philosophy and discuss ways in which they relate to the moral obligations of food scientists. It outlines methods in applied ethics of value to analysing and resolving moral issues encountered within food systems and the food industry.

Information

© The Author 2023
Moderation of [Bi3+/Na1+] molar ratio for enhancement of dielectric and energy storage properties of NaNbO3 ceramics
Authors: Babeer Afaf M , Ezzeldien Mohammed , Ali Anwar Farag , Mahmoud Abd El-razek
Published: March 2024

Lead-free (Na1−3xBix)(Nb0.75Ti0.25)O3 (x = 0.0, 0.05, 0.1, 0.125 and 0.15) (NN-BT) ceramics were synthesized using solid-state reaction technique. The effect of Bi3+ into the crystal structure, dielectric, ferroelectric and energy storage properties of NNT ceramics were investigated. Pure NNT shows present perovskite structure with orthorhombic crystal structure at x ≤ 0.125, while Na3NbO8-NaNbO3 composite phase has been detected at x = 0.15. The tolerance factor (τ) decreased from 0.97 (x = 0.0) to 0.82 (0.15) which signified the composition deviated from perovskite structure at 0.15. Significant enhancement of dielectric constant at room temperature has been achieved by increasing Bi-content and the maximum value (∼1500) obtained at 0.1. The largest value of maximum polarization (Pmax) and smallest value of remnant polarization (Pr) were achieved at x = 0.1 due to orthorhombic NaNbO3 and rhombohedral (Na0.5Bi0.5)TiO3 coexistence phases. The substitution of monovalent (Na1+) by trivalent (Bi3+) lead to create sodium vacancies into the A-sites of NNT lattice subsequently increased the cations disorder and charge misfit. The maximum recoverable energy storage density (Wrec = 17.5 J cm−3) and energy storage efficiency (η = 80%) were achieved at x = 0.1, E ∼ 700 kV cm−1. Partially, (NNTB0.1) exhibit an outstanding stability of energy storage properties in terms of temperature range (25 to 150 °C) and frequency stability (2–20Hz). The present results imply the moderation ratio of Bi/Na plays an important role for enhancement of energy storage properties of NaNbO3 anti-ferroelectric ceramics.
Beyond (and back to) Palatini quadratic gravity and inflation
Authors: Dioguardi Christian , Racioppi Antonio , Tomberg Eemeli
Published: March 2024

We study single-field slow-roll inflation embedded in Palatini F(R) gravity where F(R) grows faster than R
2. Surprisingly, the consistency of the theory requires the Jordan frame inflaton potential to be unbounded from below. Even more surprisingly, this corresponds to an Einstein frame inflaton potential bounded from below and positive definite. We prove that for all such Palatini F(R)'s, there exists a universal strong coupling limit corresponding to a quadratic F(R) with the wrong sign for the linear term and a cosmological constant in the Jordan frame. In such a limit, the tensor-to-scalar ratio r does not depend on the original inflaton potential, while the scalar spectral index ns
does. Unfortunately, the system is ill-defined out of the slow-roll regime. A possible way out is to upgrade to a F(R,X) model, with X the Jordan frame inflaton kinetic term. Such a modification essentially leaves the inflationary predictions unaffected.
Effect of diphenylalanine on the functional activity of porphyrin and non-porphyrin photosensitizers solubilized by Pluronic F127
Authors: Aksenova N A , Shershnev I V , Kardumyan V V , Chernyak A V , Timashev P S , Solovieva A B
Published: March 2024

The effect of the diphenylalanine (Phe-Phe) amino acid on the rate of tryptophan photooxidation catalyzed by photosensitizers (PS) of different natures: dimegin (DMG), fluorinated tetraphenylporphyrin (FTPP), photoditazine (PD) and methylene blue (MB) was studied. It was shown that in the presence of Phe-Phe, the effective constant of photooxidation of the substrate catalyzed by DMG, PD and MB in the aqueous phase decreases. However, the introduction of the amphiphilic polymer Pluronic F127 into the systems allows not only to restore, but also to increase the activity of the PS in the processes of photosensitized oxidation. In particular, the activity of dimegin solubilized by Pluronic F127 in the presence of Phe-Phe is higher than the activity of both pure porphyrin and solubilized DMG. In addition, the activity of the hydrophobic FTPP solubilized by Pluronic also increases. At the same time, a study of the luminescence of singlet oxygen generated by solubilized FTPP in the absence and presence of Phe-Phe revealed that the dipeptide does not influence the processes of 1О2 generation. It was suggested that micellar catalysis influences the activity of solubilized PS in the presence of a biologically active dipeptide.
Functional brain network controllability dysfunction in Alzheimer’s disease and its relationship with cognition and gene expression profiling
Authors: Zheng Chuchu , Xiao Xiaoxia , Zhao Wei , Yang Zeyu , Guo Shuixia ,   Alzheimer’s Disease Neuroimaging Initiative
Published: March 2024

Objective. In recent studies, network control theory has been applied to clarify transitions between brain states, emphasizing the significance of assessing the controllability of brain networks in facilitating transitions from one state to another. Despite these advancements, the potential alterations in functional network controllability associated with Alzheimer’s disease (AD), along with the underlying genetic mechanisms responsible for these alterations, remain unclear. Approach. We conducted a comparative analysis of functional network controllability measures between patients with AD (n = 64) and matched normal controls (NCs, n = 64). We investigated the association between altered controllability measures and cognitive function in AD. Additionally, we conducted correlation analyses in conjunction with the Allen Human Brain Atlas to identify genes whose expression was correlated with changes in functional network controllability in AD, followed by a set of analyses on the functional features of the identified genes. Main results. In comparison to NCs, patients with AD exhibited a reduction in average controllability, predominantly within the default mode network (DMN) (63% of parcellations), and an increase in average controllability within the limbic (LIM) network (33% of parcellations). Conversely, AD patients displayed a decrease in modal controllability within the LIM network (27% of parcellations) and an increase in modal controllability within the DMN (80% of parcellations). In AD patients, a significant positive correlation was found between the average controllability of the salience network and the mini-mental state examination scores. The changes in controllability measures exhibited spatial correlation with transcriptome profiles. The significant genes identified exhibited enrichment in neurobiologically relevant pathways and demonstrated preferential expression in various tissues, cell types, and developmental periods. Significance. Our findings have the potential to offer new insights into the genetic mechanisms underlying alterations in the controllability of functional networks in AD. Additionally, these results offered perspectives for a deeper understanding of the pathogenesis and the development of therapeutic strategies for AD.
Computational modeling of dorsal root ganglion stimulation using an Injectrode
Authors: Bhowmick Sauradeep , Graham Robert D , Verma Nishant , Trevathan James K , Franke Manfred , Nieuwoudt Stephan , Fisher Lee E , Shoffstall Andrew J , Weber Douglas J , Ludwig Kip A , Lempka Scott F
Published: March 2024

Objective. Minimally invasive neuromodulation therapies like the Injectrode, which is composed of a tightly wound polymer-coated Platinum/Iridium microcoil, offer a low-risk approach for administering electrical stimulation to the dorsal root ganglion (DRG). This flexible electrode is aimed to conform to the DRG. The stimulation occurs through a transcutaneous electrical stimulation (TES) patch, which subsequently transmits the stimulation to the Injectrode via a subcutaneous metal collector. However, it is important to note that the effectiveness of stimulation through TES relies on the specific geometrical configurations of the Injectrode-collector-patch system. Hence, there is a need to investigate which design parameters influence the activation of targeted neural structures. Approach. We employed a hybrid computational modeling approach to analyze the impact of Injectrode system design parameters on charge delivery and neural response to stimulation. We constructed multiple finite element method models of DRG stimulation, followed by the implementation of multi-compartment models of DRG neurons. By calculating potential distribution during monopolar stimulation, we simulated neural responses using various parameters based on prior acute experiments. Additionally, we developed a canonical monopolar stimulation and full-scale model of bipolar bilateral L5 DRG stimulation, allowing us to investigate how design parameters like Injectrode size and orientation influenced neural activation thresholds. Main results. Our findings were in accordance with acute experimental measurements and indicate that the minimally invasive Injectrode system predominantly engages large-diameter afferents (Aβ-fibers). These activation thresholds were contingent upon the surface area of the Injectrode. As the charge density decreased due to increasing surface area, there was a corresponding expansion in the stimulation amplitude range before triggering any pain-related mechanoreceptor (Aδ-fibers) activity. Significance. The Injectrode demonstrates potential as a viable technology for minimally invasive stimulation of the DRG. Our findings indicate that utilizing a larger surface area Injectrode enhances the therapeutic margin, effectively distinguishing the desired Aβ activation from the undesired Aδ-fiber activation.
A long secondary linear traction motor analysis based on electromagnetic-thermal-fluid coupling
Authors: Shi Qiying , Wen Cheng , Wang Ruiqi , Chang Wei , Han Jiacheng
Published: March 2024

The temperature analysis of the motor is critical for its functioning and durability as it has a significant impact on enhancing its efficiency. The purpose of this paper is to design a rational water cooling system for the Double-sided Linear Flux Switching Permanent Magnet motor (DLFSPM), thereby reducing the adverse effects of temperature rise. This paper conducts electromagnetic fluid and thermal analyses of DLFSPM. It also designs a rational cooling structure to reduce the temperature rise while running thereby contributing to its operation reliability. The electromagnetic-thermal-fluid coupling model provides a feasible solution for reducing the temperature increase of the DLFSPM motor under rated operating conditions, thereby enhancing its overall performance.
Performance analysis of flat plate heat pipe and heat pump heating device based on solar energy
Authors: Zhang Shan , Li Zhiyong , Han Bo , Cai Jiaxing
Published: March 2024

To solve the problem of poor heating performance of air source heat pumps when the air temperature is relatively low, this paper proposes a flat heat pipe and heat pump heating device based on solar energy. The device can store solar energy and continuously replenish the heat pump. The performance of the device is studied through experiments and simulation calculations. The results show that the difference in temperature between the evaporating section and the condensing section of the flat heat pipe is about 1°C, which shows that the heat pipe has good thermal conductivity. The device can produce a temperature rise of 7~61°C for the air entering the heat pump, which can realize the purpose of heat replenishment for the heat pump. Under the premise of no heat supply, the device can continuously heat -5°C fresh air to 5°C within 3.6 hours through the storage of solar energy. It shows that the device has good heat storage capacity. The above research shows that the device can realize the function of continuous replenishment of air source heat pump by solar energy, and has certain practical application value.
A study on the effect of temperature rise on the effectiveness of detecting typical defects in rubber-impregnated paper sleeves
Authors: Cheng Lifeng , Cui Lv , Zhou Zhengqin , Zhang Jing , Liu Yi , Wan Chengde , Cai Yuru
Published: March 2024

Epoxy rubber-impregnated paper casing has the advantages of stable electrical performance, explosion-proof function, small volume, lightweight, etc., and has been widely used in transformer casing and through-wall casing. However, its manufacturing process is complex, which makes it easy to produce defects in the production process, and it is difficult to detect certain defects in the test at room temperature. To study the partial discharge and dielectric loss characteristics of typical defects of rubber-impregnated paper bushings after temperature rise, we designed and prepared defective bushings with moisture, metal particles, and core cracks, and measured the partial discharge pattern and dielectric loss factor of the bushings after they were heated to a certain temperature. The results show that the core crack defective casing discharge increases more after heating, followed by moisture defective casing, and metal particles defective casing has the smallest impact, indicating that for the temperature rise test in the thermal state of the core crack, moisture defective casing detection effect is better. The results of the study can provide certain references and guidance for the factory inspection and troubleshooting of rubber-impregnated paper casing.
An auxiliary optimization method for electric heating renovation based on using a clustering algorithm
Authors: Li Yayun , Ma Longfei , Zeng Jiani , Lu Siyue , Du Mingjun , Wang Siyuan
Published: March 2024

The large amount of pollutants emitted by coal heating in winter is one of the main causes of haze, which brings great trouble to people’s lives. To reduce air pollution caused by coal burning and improve air quality, the state advocates the transformation of traditional electric heating methods to accelerate the transformation of China’s energy system to a clean and low-carbon model and improve the utilization rate of renewable energy in China. Therefore, this article through the calculation of the residual capacity of the retrofit and the calculation of the air conditioning load to assist the electric heating transformation. Firstly, the average power of the transformer during a high power period is calculated instead of taking the maximum power directly, which solves the problem of small residual capacity caused by a large maximum load rate and maximizes the transformable capacity. Secondly, the cluster analysis of air conditioning heating as one of the typical electric heating methods is carried out by the K-means clustering method, and the air conditioning load is obtained as the data reference during the electric heating transformation to assist the optimization transformation of electric heating. The two methods are further studied and verified by two examples, and the theory guides the practice to assist the electric heating transformation and achieve the goal of energy saving and emission reduction.
Collaborative scheduling method of power grid energy side based on carbon verification data mining algorithm
Authors: Yan Hong , Jiang Xi , Ren Xiaojun
Published: March 2024

In the process of the collaborative scheduling of the grid energy-consuming side, the voltage value is low, and the utilization rate of collaborative scheduling resources of the grid energy-consuming side is poor. Therefore, a collaborative scheduling method for the grid energy-consuming side based on a carbon verification data mining algorithm is proposed. Based on the structure of the data management system, the related data structure lookup formula is set to determine the collaborative scheduling task data of the power grid energy side. Under the carbon verification data mining algorithm, the power grid topology structure is constructed, the scheduling target parameters are processed, and the coordinated scheduling of the power grid energy side is realized. The experimental results show that this method can effectively improve the voltage value of each node, and the voltage value of all nodes can reach above the qualified value and improve the utilization rate and energy-saving performance, which has a certain effectiveness.
Research on multi-time scale optimal scheduling of integrated energy system based on digital twinning
Authors: Zhang Huailiang , Wang Kai , Dong Weiwei
Published: March 2024

Due to the differences in time scales of different units in integrated energy systems, the adaptability of dispatching to load fluctuation is low, and the corresponding cost input is large. Therefore, the research on multi-time scale optimal dispatching of integrated energy systems based on digital twinning is proposed. Based on FPGA and multiple constraints such as timing, resources, and algorithms, a digital twin model of a multi-energy integrated energy system is constructed to address the dynamic changes of various components in the time scale of the multi-energy complementary system. In the scheduling stage, the scheduling interval is determined based on the output and load parameters of each unit module in the integrated energy system, and the specific scheduling parameters are determined with the goal of digital twin mirror equivalence. In the test results, the fluctuation cost under different operation scenarios is stable below 700 yuan, and the operation cost is stable below 1, 400 yuan, both of which are at a low level.
Application of ensemble learning approach on anomaly detection of a dual induced draft fan system
Authors: Yin Xiaoyan , Wang Ze , Hao Xiaoyu , Cheng Liping , Li Rui
Published: March 2024

Intelligent monitoring of thermal power plants has been receiving growing interest. As one of the promising technologies in intelligent monitoring, machine learning-based fault detections for auxiliary equipment in the thermal power plant have been widely investigated. In this work, we constructed normal behavior models to predict the current of a dual-induced draft fan system by gradient-boosting tree regression. For anomaly detection, we evaluated the residual by calculating the mean value and meanwhile added a control boundary based on statistical analysis. As a result, we successfully identified the abnormal fan in the dual-induced draft fan system and assisted in the schedule of maintenance work.
Research on dynamic PI parameter tuning of double-fed wind turbine based on ant colony algorithm
Authors: Wang Xijun , Gong Ning , Wang Pengzhan , Ding Yan , Gu Bo
Published: March 2024

Considering the drawbacks of flexible adjustment of PI controller control parameters in the constant pressure control system of doubly fed fans, a PI controller control parameter flexible adjustment method considering ant colony optimization algorithm (ACO) is proposed. This method uses the proportional coefficient and integration time parameters in the PI controller as the ants in the ant colony optimization algorithm, and the ultimate optimization goal is to control the absolute error integration function. During the control process, the parameters of the PI controller are dynamically adjusted. When the electrified wire netting IR-drop and wind velocity changes, a comparative analysis of the dynamic tuning PI controller parameters and the non-dynamic tuning method was conducted. At last, the simulation studies have shown that the constant voltage control system using the PI parameter Flexible adjustment control method found on ACO can rapidly improve the grid voltage stability of double-fed wind turbines and reduce response time.
Comparison and analysis of starting performance of PMSM with different rotor structures
Authors: Wang Hao , Tian Rixin , Li Changchao , Chen Hong
Published: March 2024

In this paper, the electromagnetic fields of PMSM with four different rotor structures are analyzed by the finite element method, and the distribution of magnetic field lines is compared. Then the asynchronous starting process of PMSM is studied. The starting process of four kinds of permanent magnet synchronous motors with no load and load is simulated and analyzed, and the characteristics of speed, torque, and phase current are obtained. These studies can provide references for the starting design of permanent magnet synchronous motors in practical applications. Therefore, a more reliable and efficient motor starting process is realized, which provides a basis for further structural design of permanent magnet synchronous motor.
A simple and efficient resonant DC link inverter with low current stress on main switch
Authors: Jia Xiaodong , Xia Wen , Song Jiaxiang
Published: March 2024

This paper proposes a simple and efficient resonant DC link inverter topology with low current stress on main switches. The inverter has a straightforward structure and is readily controllable, avoids the auxiliary resonant current passing through the main switches of the inverter, and the current passing through the main switches remains consistently equivalent to the load current, thus reducing the current stress and the switching loss of the main switches, thereby the inverter’s efficiency is increased. The proposed inverter’s operating principle is examined and contrasted with the inverter described in the literature. Ultimately, the validity of the resonant DC link inverter is demonstrated through simulation.
Flexible closed-loop control device and control method for distribution network based on hybrid phase shifting transformer
Authors: Gan Dongliang , Yuan Jiaxin , Li Guangyao
Published: March 2024

With the increasingly complex structure of the distribution network and the increasing demand for power supply quality from the user side, relying solely on the original grid layout for power supply can no longer meet existing needs. Closed loop power supply can achieve uninterrupted load to improve power supply reliability. This article proposes a flexible loop closing device based on HPST for the case of large voltage phasor differences on both sides of the busbar loop closing point in the distribution network and proposes corresponding flexible loop closing and load transfer strategies based on the characteristics of HPST. Finally, a simulation of loop closure and power control was conducted based on the 10 kV distribution network loop closure scenario, verifying the feasibility of the HPST flexible loop closure device and the effectiveness of the control strategy.
Risk assessment of distribution network operation with scale distributed photovoltaics
Authors: Guo Xiaofang , Miao Guixi , Wang Xin , Yuan Liang , Li Wen , Wu Entong , Yibulayimu Xierzhati
Published: March 2024

In the context of large-scale photovoltaic integration into the distribution network, it is of great significance to comprehensively consider the uncertainty of photovoltaic output and load and scientifically and effectively evaluate the operational risks of the distribution network, in order to ensure the reliable and economic operation of the distribution network. At the same time, with the increase of distributed photovoltaic installed capacity, the small interference stability caused by it has an increasing impact on the operation of the distribution network. In this paper, we first establish a probabilistic model of photovoltaic output and load. Then, we propose a risk calculation method based on the non-sequential Monte Carlo method and probabilistic power flow calculation. Then, a risk analysis of large-scale photovoltaic access to the distribution network was carried out. A new small interference stability risk index was constructed to evaluate the risk of system oscillation caused by photovoltaic access. On this basis, the comprehensive risk value is calculated, and the risk levels are divided based on the voltage over-limit risk and power flow over-limit risk. Finally, the feasibility and effectiveness of the risk assessment model are verified through case analysis.
Study on the topology of a system for delivery of electricity from deep sea wind through voltage source converter
Authors: Chen Qichen , Gang Mingze , Zhao Zheng , Zhang Yiming , Teng Shangfu , Fan Linzhen
Published: March 2024

It is a difficult problem to maintain high reliability while designing the topology of the voltage source converter (VSC) for deep-sea wind power in a compact manner. In this paper, the topology of the converter, the main wiring type and grounding method, and the DC system wiring scheme are studied. The advantages and disadvantages of each scheme are compared in offshore wind power application scenarios. Finally, the half-bridge converter topology and the true bipolar with metal return line topology are recommended for the topology design of the VSC system for deep and remote offshore wind power. The power operating range is also presented. The scheme proposed in this paper paves the way for promoting the lightweight and highly reliable system for the delivery of electricity from deep sea wind through VSC.
Anomaly attribute mining method for topological nodes of power system based on graph theory
Authors: Tan Huijuan , Lu Jiangang , Zhao Ruifeng , Dai Yue , Wu Yuezhou
Published: March 2024

Due to the large scale, high dimension and time series characteristics of power system data, and the normal samples far exceed the abnormal samples, the sample imbalance phenomenon occurs, and it is difficult to mine the abnormal attributes of nodes. Therefore, a method of mining abnormal attributes of topological nodes of power systems based on graph theory is developed. The logical relation between nodes is analyzed by graph theory, and directed graph and undirected graph are obtained. The topology structure of the power system is constructed, the noise in data is removed by the adaptive clustering algorithm, the weight of topological nodes is set, and the abnormal malicious attacks of topological nodes are discovered by the double threshold method. The experimental results show that the proposed method can accurately detect the abnormal topological nodes in the network, perform better in the energy consumption of the neighbor topological nodes, and greatly reduce the energy consumption of the neighbor topological nodes during mining.
Application of indoor and outdoor integrated collaborative positioning technology in power transportation detection
Authors: Hao Xiangyu , Zhao Junlei , Li Chunxiao , Wang Lei
Published: March 2024

With the continuous acceleration of the construction of electric power Internet of Things, the structure and scale of electric power system is more massive, the complexity and danger coefficient of field operation is enhanced, and the risk of causing safety accidents is further increased. Therefore, based on wireless sensor network, collecting and transmitting information of personnel and site operation environment, establishing power operation tracking system is of great significance to improve the safety and efficiency of operation and inspection personnel. At present, most of the electric power operation and maintenance personnel are positioned by satellite or wireless WIFI, which has a large error or even cannot be positioned, so this paper proposes a 5G+Beidou fusion indoor-outdoor cooperative positioning technology for electric power operation and inspection service. The fusion model of Beidou carrier phase differential positioning and 5G cellular network positioning is established by using the improved Federal Kalman filter algorithm, which can avoid data pollution caused by Beidou receiver failure or 5G communication module failure in a complex environment, and avoid the inability to locate compared with the common Federal Kalman filter. phenomenon.