bluuebunny/crossref_metadata_2025 huggingface dataset:
The GAPS Programme at TNG
Authors: Ruggieri A. , Desidera S. , Sozzetti A. , Marzari F. , Pinamonti M. , Gratton R. , Biazzo K. , D’Orazi V. , Malavolta L. , Mesa D. , Claudi R. , Benatti S. , Bignamini A. , Cabona L. , Chauvin G. , Hagelberg J. , Mancini L. , Mantovan G. , Molinaro M. , Nardiello D. , Scandariato G. , Vigan A. , Zingales T.
Published: July 2024

Context. Due to observational biases, a large fraction of known exoplanets are short-period objects. However, the search for planets began more than 20 yr ago, and so it is already possible – with the use of a suitable dataset – to begin exploring a wider range of the parameter space, such as that encompassing long-period planets.

Aims. The aim of this paper is to investigate the presence of long-period giant companions in two systems where one or more planets are already known and for which a long-term trend in the radial velocities (RVs) was noted in previous works.

Methods. Over the last 11 yr, we have collected 122 spectra of HD 75898 and 72 spectra of HD 11506 with the High Accuracy Radial velocity Planet Searcher for the Northern hemisphere (HARPS-N) in the framework of the Global Architecture of Planetary Systems (GAPS) project, from which we derived precise RV and activity indicator measurements. Additional RV data from the High-Resolution Echelle Spectrometer (HIRES) are also used here to increase the total time span. For our RV analysis, we used PyORBIT, an advanced Python tool for the simultaneous Bayesian analysis of RVs and stellar activity indicators. In addition, we used astrometric (Gaia DR3) and imaging archive data to complete our analysis. In particular, we combined RVs and astrometry to better constrain the mass and period of the new long-period companions.

Results. We find evidence for one additional long-period companion (gas giant planet or brown dwarf) in both systems considered. The new candidate for HD 75898 has a period of roughly 18 yr and a true mass of around 8.5 Mj. For HD 11506, we confirm the new object (planet d) recently announced using HIRES data but we find that the period and true mass are both almost double the values based on HIRES results (Pd ~ 72 yr, Md ~ 13 Mj). In addition, for HD 75898, we also find evidence of an activity cycle affecting RVs with a period of one order of magnitude lower than found in the literature.
Over-order multiplicities and their application in controlling delay dynamics.
On zeros’ distribution of linear combinations of Kummer hypergeometric functions
Authors: Boussaada Islam , Mazanti Guilherme , Iulian Niculescu Silviu
Published: July 2024

A series of recent works have shown that, for a system of linear functional differential equations, a spectral value having a multiplicity exceeding the order of the system tends to correspond to the spectral abscissa of the system, a property called MID for multiplicity-induced-dominancy. In particular, when this multiplicity coincides with the degree of the characteristic quasipolynomial, this property is called generic MID (GMID), in opposition to the intermediate MID (IMID), which corresponds to a multiplicity strictly smaller than the degree. The GMID has been fully characterized for single-delay retarded as well as neutral delay-differential equations thanks to the representation of the corresponding quasipolynomial in terms of a Kummer hypergeometric function. However, apart from partial results, in full generality, no result of the literature enables the characterization of the dominance of a spectral value having an intermediate multiplicity, which is essentially due to the lack of existing results among the open literature pertaining to linear combinations of Kummer functions’ zeros distribution. In this work, we overcome this difficulty and we further investigate the MID to cover the so-called over-order MID, that is, the cases where the multiplicity is larger than the order of the corresponding differential equation.
Control of waves on Lorentzian manifolds with curvature bounds
Authors: Kumar Jena Vaibhav , Shao Arick
Published: July 2024

We prove boundary controllability results for wave equations (with lower-order terms) on Lorentzian manifolds with time-dependent geometry satisfying suitable curvature bounds. The main ingredient is a novel global Carleman estimate on Lorentzian manifolds that is supported in the exterior of a null (or characteristic) cone, which leads to both an observability inequality and bounds for the corresponding constant. The Carleman estimate also yields a unique continuation result on the null cone exterior, which has applications toward inverse problems for linear waves on Lorentzian backgrounds.
Herzinsuffizienz bei Patienten mit Diabetes mellitus
Authors: Schütt Katharina , Polzin Amin
Published: July 2024

Patienten mit Diabetes haben ein erhöhtes Risiko, eine Herzinsuffizienz zu entwickeln, und das Vorliegen beider Komorbiditäten geht mit einer schlechteren Prognose einher. Daher ist es von größter Bedeutung, eine Herzinsuffizienz bei Patienten mit Diabetes frühzeitig zu erkennen und umgekehrt alle Patienten mit Herzinsuffizienz auf das Vorhandensein eines Diabetes mellitus zu screenen. Dies ist besonders wichtig, da das Vorliegen einer Herzinsuffizienz bei Patienten mit Diabetes häufig eine Anpassung der antidiabetischen Therapie notwendig macht. Insgesamt ist die Umsetzung der leitliniengerechten Therapien zur Reduzierung des kardiovaskulären Risikos in dieser Hochrisikopopulation von entscheidender Bedeutung. Der vorliegende Artikel legt die Besonderheiten bei der Therapie von Patienten mit Herzinsuffizienz und begleitendem Diabetes mellitus dar.
Technikbasierte Interventionen in der Sport- und Bewegungstherapie
bei Menschen mit Diabetes mellitus Typ 2
Authors: Brinkmann Christian , Denzin Julian , Behrens Meinolf
Published: July 2024

In dieser Übersichtsarbeit werden Möglichkeiten technikbasierter Interventionen
in der Sport- und Bewegungstherapie von Menschen mit Typ-2-Diabetes mellitus
(T2DM) vorgestellt und deren Wirksamkeit zur Steigerung des Bewegungsverhaltens
und Verbesserung klinischer Variablen aufgezeigt. Dabei zeigen sich bei
mobile-Health-Interventionen (mHealth) zum Teil ähnliche Wirkungen wie bei einem
konventionellen Training. Der Einsatz von Sensortechnologie (z. B.
Schrittzähler, Beschleunigungsmesser, Systeme zur kontinuierlichen
Glukosemessung (CGM)) kann ein verstärktes Bewusstsein für gesundheitsrelevante
Faktoren schaffen und sich positiv auf die Verbesserung der glykämischen
Kontrolle auswirken. Es werden jedoch mehr qualitativ hochwertige Studien (mit
homogenen Studiendesigns) und Meta-Analysen benötigt, um die Aussagekraft der
Evidenz zu erhöhen und klare und zuverlässige Empfehlungen für den Einsatz von
Technik bei Sport- und Bewegungsinterventionen für Menschen mit T2DM zu geben.
Herausforderungen vorwiegend technikbasierter Interventionen sind die Schaffung
einer langfristigen Adhärenz, ausreichende Sicherheit beim Training und
Datenschutzangelegenheiten.
Körperliche Aktivität und gesunde Ernährung zur Prävention und
Therapie des Gestationsdiabetes mellitus
Authors: Meuffels Frederike Maria , Levcenko Jessica , Brinkmann Christian
Published: July 2024

Einleitung Die Entstehung und Progression von Gestationsdiabetes mellitus
(GDM) wird neben anderen Faktoren durch das Bewegungs- und Ernährungsverhalten
der Mutter beeinflusst. Evidenzbasierte Empfehlungen sind in der S3-Leitlinie
GDM festgehalten. Ziel der Umfrage war es herauszufinden, ob schwangere Frauen
über körperliche Aktivität und gesunde Ernährung von ihren FrauenärztInnen (FrÄ)
aufgeklärt werden und ob sie sich ausreichend zu den Themen informiert
fühlen.

Methode Durch eine Online-Umfrage wurden schwangere Frauen (n=62) in Berlin
mit und ohne GDM dazu befragt.Ergebnisse Lediglich circa die Hälfte der
Befragten gab an, mit ihrer Gynäkologin/ihrem Gynäkologen überhaupt über
körperliche Aktivität (52%) und gesunde Ernährung (45%) gesprochen zu haben.
Weniger als die Hälfte aller Frauen (39%) war mit der Beratung zu den Themen
körperliche Aktivität und Ernährung zufrieden.

Fazit Die Beratung von Schwangeren durch ihre FrÄ zu den Themen Bewegung
und gesunde Ernährung bei GDM besitzt den Ergebnissen zufolge deutliches
Verbesserungspotenzial. Die Verbreitung von Schulungsmaterialien in
gynäkologischen Praxen könnte sinnvoll sein.
Partizipative Bewegungsförderung in der beruflichen
Bildung
Authors: Grüne Eva , Popp Johanna , Carl Johannes , Semrau Jana , Pfeifer Klaus
Published: July 2024

In der Bewegungs- und Gesundheitsförderung wächst das Interesse an
Beteiligungsansätzen, die auf einer Zusammenarbeit zwischen
Wissenschaftler*innen und nichtakademischen Akteur*innen beruhen. Der
kooperative Planungsansatz, der verschiedene Akteur*innen aus Wissenschaft,
Politik und Praxis in einen gleichberechtigten Entscheidungsprozess zur Planung,
Entwicklung und Implementierung von Maßnahmen zur Bewegungsförderung einbezieht,
entspricht einem solchem Beteiligungsansatz. Im Rahmen des Projekts PArC-AVE
wurden in der Vergangenheit fünf kooperative Planungsprozesse im Bereich der
beruflichen Bildung durchgeführt, die zur Entwicklung und Implementierung
bewegungsförderlicher Maßnahmen führten. Auf der Grundlage der umfangreichen
Ergebnisse aus dem Projekt PArC-AVE werden in dem vorliegenden Artikel
Handlungsempfehlungen für die partizipative Bewegungsförderung in der
beruflichen Bildung dargestellt. Diese Handlungsempfehlungen enthalten eine
Beschreibung konkreter Umsetzungsschritte der Vorbereitungs-, Entwicklungs- und
Implementierungsphase sowie der Evaluation eines kooperativen Planungsprozesses
und bieten damit eine wertvolle Orientierungshilfe zur Durchführung zukünftiger
kooperativer Planungsprozesse im Bereich der beruflichen Bildung.
Outcome after colorectal full-thickness resection and management of recurrence
Authors: Mueller Julius , Miedtke Valentin , Kuellmer Armin , Schiemer Moritz , Bettinger Dominik , Thimme Robert , Schmidt Arthur
Published: July 2024

Background and study aims Endoscopic full-thickness resection
(eFTR) allows treatment of “difficult to resect” lesions not amenable to conventional
endoscopic methods. Efficacy and safety of the system have already been proven in numerous
studies. Follow-up data on outcome of colorectal eFTR and management of recurrences are still
rare.

Patients and methods All patients undergoing colorectal eFTR at
our institution with at least one endoscopic follow-up examination were retrospectively
analyzed. The primary endpoint was the rate of recurrent or residual lesions (RRLs) and the
secondary endpoint was the rate of late adverse events (AEs). We further aimed to identify
risk factors for RRLs and to describe their management.

Results Between November 2014 and 2021, 141 patients underwent
eFTR at University Medical Center Freiburg. Ninety-one patients fulfilled the inclusion
criteria. Indications for eFTR were non-lifting adenoma (n = 65), subepithelial tumors (n =
18) and early carcinoma (n = 8). The median follow-up period was 17 months (range, 2–86). The
overall RRL rate was 9.9% (9/91). A significant proportion of RRLs (6/9, 66%) were detected
late. All RRLs occurred in the group of non-lifting adenoma, corresponding to a RRL rate of
13.8% in this subgroup. Thirty-three percent (3/9) were initially treated by hybrid eFTR. Of
the RRLs, 66.6% could were successfully treated endoscopically. On χ2 analysis, the hybrid
eFTR technique (P = 0.006) was associated with a higher rate of
RRL. No late AEs occurred.

Conclusions The rate of RRL after colorectal eFTR is low and the
majority could be treated endoscopically. For non-lifting adenomas and early carcinomas, close
follow-up is mandatory to detect late recurrence. Long-term outcomes after hybrid eFTR need
further investigation.
Lymphatic Mapping with Multi-Lymphosome Indocyanine Green Lymphography in Legs with Lymphedema
Authors: Hara Hisako , Mihara Makoto
Published: July 2024

It is observed that the locations of the most functional lymphatic vessels in the lymphedematous limbs can differ significantly from those in healthy limbs. The aim of this study was to elucidate the lymphatic map of lymphedematous limbs. We retrospectively analyzed 59 patients (118 limbs) with lower limb lymphedema. Fifty-five were women and four were men. The mean age and duration of lymphedema was 62.4 and 7.7 years, respectively. For the lateral thigh lymphosome, we injected indocyanine green (ICG) at the lateral knee and measured the distance (Dt) between the anterior superior iliac spine (ASIS) and the point where the lymphatic vessels crossed the reference line (the line connecting the ASIS and the patellar center). For the lateral calf lymphosome, we injected ICG at the lateral ankle and measured the distance (Dc) between the inferior patellar border and the point where the lymphatic vessels crossed the reference line (the anterior border of the tibia). In the lateral thigh, the mean Dt was 30.4 ± 0.6 cm (range, 0–41 cm) and the distribution peaked at approximately 30 cm from the ASIS. In the calf, the mean Dc was 13.1 ± 0.9 cm (range, −11 to 32 cm). The distribution of lymphatic vessel locations was highly variable. We could establish the lymphatic map in the lymphedematous legs. The distribution of lymphatic vessels in the thigh and lower legs had one and two peaks, respectively.
Interprofessional Evaluation of a Medication Clinical Decision Support System Prior to Implementation
Authors: Bauer Jacqueline , Busse Marika , Kopetzky Tanja , Seggewies Christof , Fromm Martin F. , Dörje Frank
Published: July 2024

Background Computerized physician order entry (CPOE) and clinical decision support systems (CDSS) are widespread due to increasing digitalization of hospitals. They can be associated with reduced medication errors and improved patient safety, but also with well-known risks (e.g., overalerting, nonadoption).

Objectives Therefore, we aimed to evaluate a commonly used CDSS containing Medication-Safety-Validators (e.g., drug–drug interactions), which can be locally activated or deactivated, to identify limitations and thereby potentially optimize the use of the CDSS in clinical routine.

Methods Within the implementation process of Meona (commercial CPOE/CDSS) at a German University hospital, we conducted an interprofessional evaluation of the CDSS and its included Medication-Safety-Validators following a defined algorithm: (1) general evaluation, (2) systematic technical and content-related validation, (3) decision of activation or deactivation, and possibly (4) choosing the activation mode (interruptive or passive). We completed the in-depth evaluation for exemplarily chosen Medication-Safety-Validators. Moreover, we performed a survey among 12 German University hospitals using Meona to compare their configurations.

Results Based on the evaluation, we deactivated 3 of 10 Medication-Safety-Validators due to technical or content-related limitations. For the seven activated Medication-Safety-Validators, we chose the interruptive option [“PUSH-(&PULL)-modus”] four times (4/7), and a new, on-demand option [“only-PULL-modus”] three times (3/7). The site-specific configuration (activation or deactivation) differed across all participating hospitals in the survey and led to varying medication safety alerts for identical patient cases.

Conclusion An interprofessional evaluation of CPOE and CDSS prior to implementation in clinical routine is crucial to detect limitations. This can contribute to a sustainable utilization and thereby possibly increase medication safety.
Language learning in times of danger
Authors: Fernández Susana S. , Appel Christine
Published: July 2024

In this paper, we contribute to the study of intercultural pragmatics and, more specifically, the
“pragmatics of danger” by exploring how adult participants in an online exchange program with focus on Spanish and English
learning talk about the corona virus and the impact the pandemic has in their lives. We focus on the Covid-19 related topics
that emerge in their exchanges and we search for keywords and eventual new words and concepts that shed light on people’s
situation at the time. Our material, consisting of video recordings of participant conversations, is from the month of April
2020, a month into the global lockdown. It therefore provides us with a valuable snapshot of a time characterized by
insecurity on how things would evolve and on to what degree the pandemic would disrupt life as we knew it.
The cultural pragmatics of “danger” in Chinese political discourse
Authors: Ye Zhengdao
Published: July 2024

This chapter examines a way of speaking about “looming danger” that is pervasive in Chinese Communist
Party discourse but which has not been given much attention in studies of Chinese elite politics. It centres on cultural
beliefs underlying the discourse of jū ān sī wēi (‘think about danger during peaceful time’) and unpacks its
associated meaning and the cultural contents surrounding this discourse. The paper argues and demonstrates that political
discourse is a form of cultural pragmatics, in that the former builds on fundamental beliefs and values of the culture in
which the discourse is situated, and that these beliefs and values may be influenced and reinforced by historical events and
national memory. It also demonstrates that Natural Semantics Metalanguage can be a useful tool for analysing and representing
the cultural elements in political discourse.
Optimizing charge transport and band-offset in silicon heterojunction solar cells: impact of TiO2 contact deposition temperature
Authors: Pandey Anand , Kumar Tarun , Mondal Arnab , Bag Ankush
Published: July 2024

Carrier selective contacts are a primary requirement for fabricating silicon heterojunction solar cells (SHSCs). TiO2 is a prominent carrier selective contact in SHSCs owing to its excellent optoelectronic features such as suitable band offset, work function, and cost-effectiveness. Herein, we fabricated simple SHSCs in an Al/TiO2/p-Si/Ti/Au device configuration. Ultrathin 3 nm TiO2 layers were deposited onto a p-type silicon substrate using the atomic layer deposition method. The deposition temperature of TiO2 layers varied from 100 °C to 250 °C. X-ray photoelectron spectroscopic studies suggest that deposition temperature highly affects the chemical states of TiO2 and reduces the formation of defective state densities at the Fermi energy. The optical band gap values of TiO2 layers are also altered from 3.13 eV to 3.27 eV when the deposition temperature increases. The work function tuning from −5.13 eV to −4.83 eV has also been observed in TiO2 layers, suggesting the variation in Fermi level tuning, which arises due to changes in carrier concentrations at higher temperatures. Several device parameters, such as ideality factor, trap density, reverse saturation current density, barrier height, etc, have been quantified to comprehend the effects of deposition temperature on photovoltaic device performance. The results suggest that the deposition temperature significantly influences the charge transport and device performance. At an optimum temperature, a significant reduction in charge carrier recombination and trap state density has been observed, which helps to improve power conversion efficiency.
Double autocorrelation-based cyclicity evaluation for repetitive transients feature extraction
Authors: Liang Lin , Wang Junjing , Liu Dan , Hu Wenhao , Qiao Miaomiao
Published: July 2024

The vibration response caused by bearing local defects has impact and periodicity in waveform, which provides a standard for the frequency band selection in envelope analysis. However, most periodicity measurements without prior knowledge belong to sparsity evaluation, while the defects of sparsity index in nature are inevitable. Inspired by the periodic component extraction of autocorrelation function, a novel cyclicity measurement based on double autocorrelation calculation is proposed. With the help of normalization, this approach can distinguish periodic impulses from random impulses by using the periodic sub-maxima of the envelope autocorrelation. Considering the influence of the noise component on the autocorrelation of the periodic signal, the sub-maximums are maintained by threshold processing. On this basis, the re-autocorrelation is calculated to identify the periodic sub-maximum. Finally, as a non-prior index, a demodulation band selection is also proposed in combination with an impulsivity evaluation. The results of the proposed method are analyzed and verified by comparison with typical methods.
Entropy production and the generalised second law of black hole thermodynamics
Authors: Sofos Iason A , Kanzi Sara , Varcoe Benjamin T H
Published: July 2024

The generalised second law of black hole thermodynamics states that the sum of a black hole’s entropy and the entropy of all matter outside the black hole cannot decrease with time. The violation of the generalised second law via the process in which a distant observer extracts work by lowering a box arbitrarily close to the event horizon of a black hole has two profound ramifications: (1) that the entropy of the Universe can be decreased arbitrarily via this process; and (2) that it is not appropriate to apply the laws of thermodynamics to systems containing black holes. In this paper, we argue that for the generalised second law to not be violated, entropy must be produced during the lowering process. To demonstrate this, we begin by deriving an equation for the locally measured temperature of the vacuum state of an observer that is a finite distance from the event horizon of a Schwarzschild black hole. Then, using this locally measured temperature and the Unruh effect, we derive an equation for the force required to hold this observer in a stationary position relative to a Schwarzschild black hole. These equations form a framework for calculating the change in black hole entropy as a result of the lowering process both in the case where the process is isentropic and in the case where entropy is produced during the lowering process. In the latter case, two requirements: (1) that the resultant change in black hole entropy is finite; and (2) that the resultant change in common entropy is finite, are used to identify two conditions that the form of an entropy production function must satisfy. These, in turn, are used to identify a set of possible functions describing the production of entropy. Using this set of functions, we demonstrate that the production of entropy limits the amount of work that the distant observer can extract from the lowering process. We find that this allows for the generalised second law to be preserved, provided that a coefficient in this set of functions satisfies a given bound. To conclude, we discuss two natural choices of this coefficient that allow for the generalised second law to be preserved in this lowering process. In addition to providing a resolution to this violation of the generalised second law, the framework presented in this paper can be applied to inform theories of gravity and quantum gravity on the form of their entropy relations, such that they do not violate the generalised second law.
A novel single mode fiber optic temperature sensor combined with the FLRDS technique
Authors: Kaya Burak Malik
Published: July 2024

A single mode optical fiber loop was employed as a temperature sensor to observe changes in optical loss regarding to ringdown time (RDT) by high sensitive the fiber loop ringdown spectroscopy (FLRDS) technique which has real-time and fast response measurement capability due to allowing trapped light pulse multiple interactions with the measurands. Two different fiber loops of 45 ± 5 m and 120 ± 5 m lengths were embedded one by one into a copper, circular and closed housing. Continuous monitoring of RDTs was carried out by changing the temperature in the range of 25–200 °C with the steps of 25 °C for the first time by using bare fiber without any modification as a temperature sensor. The FLRDS system for temperature sensing has simple design without extra components such as an optical time domain reflectometer (OTDR), long-period fiber grating (LPFG) or fiber Bragg grating (FBG) as sensorhead. The FLRDS system was diligently optimized to achieve the lowest baseline as %0.49. Since the RDT of the FLRDS system was changed due to the thermal expansion of the fiber, continuous monitoring of the temperature was the first time recorded by utilizing this kind of FLRDS temperature sensor. These kind of FLRDS temperature sensors have high potential to be employed in mining, nuclear facilities, railways, underwater structures, biomedical, medicine, structural health monitoring, transportation and communication applications with simple system setup, lower cost, higher sensitivity, portability, real-time and continuous monitoring for early detection.
Synthesis of uniform sized ZnS quantum dots using hydrodynamic cavitation and their characterization
Authors: Zhang Jince , Qi Xiaochen , Liu Di , Hu Yixiang , Chen Yukun , Zhou Ziyue , Jin Taiyu , Fang Dawei , Wang Jun
Published: July 2024

As representative non-toxic cadmium-free quantum dots (QDs), ZnS QDs with high quantum efficiency, super stability and excellent biocompatibility had attracted wide attention in the fields of photocatalysis, solar cells and biomedicine. In this study, hydrodynamic cavitation (HC) technology was applied to the preparation of ZnS QDs. By adjusting HC device parameters, water soluble ZnS QDs with small particle size, narrow particle size distribution range, high absorbance, high luminous efficiency and high quantum yield were prepared. The morphology, size distribution, element composition and optical properties of ZnS QDs were studied by various characterization methods. ZnS QDs with average particle size of 1.48 nm, fluorescence quantum yield of 34.07% and Stokes shift of 112 nm were obtained. In addition, the mechanism of preparation of ZnS QDs by using HC method was also studied. It is hoped that this HC technology can provide a new idea for large-scale preparation of ZnS QDs with excellent properties.
Gapless edge-modes and topology in the Qi-Wu-Zhang model: a real-space analysis
Authors: Dasgupta Arjo , Dasgupta Indra
Published: July 2024

The topological phase transition in the Qi-Wu-Zhang model is studied using a real-space approach. An effective Hamiltonian for the topologically protected edge-modes in a finite-size system is developed. The topological phase transition is understood in terms of a global perturbation to the system which lifts the degeneracy of the edge-modes. The effective Hamiltonian method is also applied to a one-dimensional system with spatially varying hopping strengths to understand the impact of disorder on the edge-modes.
Combined speed and distance control for optimized vehicle platooning
Authors: Güzey Hacı Mehmet
Published: July 2024

This paper presents a novel approach to vehicle platooning using combined formation-regulation control, aiming to enhance the operation of Connected and Autonomous Vehicles (CAVs). By integrating advanced control algorithms with precise positioning and synchronization tools, our methodology enables CAVs to autonomously navigate while maintaining minimal inter-vehicle distances, thus optimizing convoy synchronization. The proposed system consists of two main controllers: a speed consensus controller to synchronize vehicle speeds and a following distance controller to ensure safety. Our combined control approach combines these controllers dynamically based on real-time vehicle spacing, employing exponential functions to smooth the transition between control modes, thereby preventing abrupt changes in vehicle behavior. This method not only increases energy efficiency and traffic throughput but also significantly reduces the likelihood of accidents caused by sudden braking, contributing to decreased fuel consumption and enhanced road safety. Our work not only advances the technology of vehicle platooning but also promises broader implications for the overall transportation ecosystem.
Effect of plasma initialization on 3D PIC simulation of Hall thruster azimuthal instability
Authors: Xie Lihuan , Luo Xin , Zhou Zhijun , Zhao Yinjian
Published: July 2024

The lack of understanding of the azimuthal instability and the resulting electron anomalous transport limits further improvement of Hall thrusters. Compared to theoretical and experimental approaches, the numerical particle-in-cell (PIC) simulation is a suitable and powerful tool, which has been widely applied to investigate the azimuthal instability, and great progress has been made in the past decades. However, PIC simulations are intrinsically computationally expensive, and it is realized that the Hall thruster azimuthal instability has a three dimensional nature. Therefore, massive 3D PIC simulation must be carried out to completely reveal the mechanism of the instability. In this paper, the effect of plasma initialization on 3D PIC simulation of Hall thruster azimuthal instability is studied as a starting point. It is found that by initializing with ion density and velocity fitting functions to the steady-state simulation results, a faster convergence can be obtained and the computational time can be reduced by about 1.5 times. Typical fitting functions of ion density, drifting velocity, and temperature are given, and the influence of different initialization profiles is presented.
Quadratic perturbations of the Schwarzschild black hole: the algebraically special sector
Authors: Achour Jibril Ben , Roussille Hugo
Published: July 2024

We investigate quadratic algebraically special perturbations (ASPs) of the Schwarzschild black hole. Their dynamics are derived from the expansion up to second order in perturbation of the most general algebraically special twisting vacuum solution of general relativity. Following this strategy, we present analytical expressions for the axial-axial, polar-polar and polar-axial source terms entering in the dynamical equations. We show that these complicated inhomogeneous equations can be solved analytically and we present explicit expressions for the profiles of the quadratic ASPs. As expected, they exhibit exponential growth both at the past and future horizons even in the non-linear regime. We further use this result to analyze the quadratic zero modes and their interpretation in terms of quadratic corrections to mass and spin of the Schwarzschild black hole. The present work provides a direct extension beyond the linear regime of the original work by Couch and Newman.
Revisiting primordial black hole capture by neutron stars
Authors: Caiozzo Roberto , Bertone Gianfranco , Kühnel Florian
Published: July 2024

A sub-solar mass primordial black hole (PBH) passing through a neutron star, can lose enough energy through interactions with the dense stellar medium to become gravitationally bound to the star. Once captured, the PBH would sink to the core of the neutron star, and completely consume it from the inside. In this paper, we improve previous energy-loss calculations by considering a realistic solution for the neutron star interior, and refine the treatment of the interaction dynamics and collapse likelihood. We then consider the effect of a sub-solar PBH population on neutron stars near the Galactic center. We find that it is not possible to explain the lack of observed pulsars near the galactic center through dynamical capture of PBHs, as the velocity dispersion is too high. We then show that future observations of old neutron stars close to Sgr A* could set stringent constraints on the PBHs abundance. These cannot however be extended in the currently unconstrained asteroid-mass range, since PBHs of smaller mass would lose less energy in their interaction with the neutron star and end up in orbits that are too loosely bound and likely to be disrupted by other stars in the Galactic center.
Path integral formalism of open quantum systems with non-diagonal system-bath coupling
Authors: Chen Ruofan
Published: July 2024

Most path integral expressions for quantum open systems are formulated with diagonal system-bath coupling, where the influence functional is a functional of scalar-valued trajectories. This formalism is enough if only a single bath is under consideration. However, when multiple baths are present, non-diagonal system-bath couplings need to be taken into consideration. In such a situation, using an abstract Liouvillian method, the influence functional can be obtained as a functional of operator-valued trajectories. The value of the influence functional itself also becomes a superoperator rather than an ordinary scalar, whose meaning is ambiguous at first glance and its connection to the conventional understanding of the influence functional needs extra careful consideration. In this article, we present another concrete derivation of the superoperator-valued influence functional based on the straightforward Trotter–Suzuki splitting, which can provide a clear picture to interpret the superoperator-valued influence functional.
Heralded hyper-CNOT gates for two-photon systems assisted by quantum scattering in waveguides
Authors: Zhang Jing-Xue , Sun Xue-Tong , Wang Lin-Xiong , Wei Hai-Rui , Song Guo-Zhu
Published: July 2024

Photonic hyper-parallel quantum gates play a critical role in high-capacity quantum communication and fast quantum computing. Here, based on photon scattering in one-dimensional (1D) waveguides, we present some heralded schemes for constructing four-qubit hyper-controlled-not (hyper-CNOT) gates in two-photon systems. The qubits are encoded on both the polarization and spatial-mode degrees of freedoms (DOFs) of the photons, which can simplify the quantum circuit and reduce the quantum resource consumption. In our schemes, the faulty scattering events between photons and emitters caused by system imperfections can be filtered out and discarded. That is, our protocols for hyper-CNOT gates work in a heralded way. Our calculations show that, with great progress in the emitter-waveguide systems, our photonic hyper-CNOT gates may be experimentally feasible.
Analysis of Transformer GSB Bushing Fault Causes Based on Finite Element Simulation
Authors: Xu Shurong , Liu Jun , Li Kun , Ma Hong , Chen Peilong , Huang KeJie
Published: July 2024

In response to a sudden explosion and fire fault during the operation of a GSB dry-type transformer bushing in a certain power grid company, based on the structural parameters of the bushing measured by the supplier and on-site, a reverse design of the capacitor core was carried out on the faulty bushing. Based on the measured parameters and reverse design results, a finite element simulation model of the bushing electric field and structural force field was established. Calculate the electric field distribution of the casing under normal operation, 60s power frequency withstand voltage, lightning impulse, operation impulse, and other operating conditions; Conduct finite element simulation of structural mechanics to calculate the stress distribution of the casing under conditions such as cantilever load and short circuit impact; Based on the discharge traces discovered during disassembly, simulation calculations were conducted by assuming the defect situation of the casing, and the electric field distribution of the casing under different defect types was quantitatively analyzed. The simulation calculation results of the electric field under various working conditions have verified that the occurrence of this fault is the result of multiple defects working together, providing quantitative support for fault analysis and providing a certain reference for the operation and maintenance of similar casings.
Research on Pressure Sensor of Circular Monocrystalline Silicon Chassis
Authors: Zhu Ziyi , Zhang Shougang , Ruan Jun
Published: July 2024

Traditional sensors, such as pressure, piezoelectric or piezoresistive, mostly use square silicon-based materials as chassis and use Wheatstone bridge circuits to measure pressure and resistance values. Nowadays, reducing the size of sensors is also a problem to be solved in the increasingly wide range of sensor applications. In this paper, a circular monocrystalline silicon base pressure sensor is designed and its performance is studied. We applied COMSOL software to model the circular chassis base pressure sensor, tested the deformation of the circular chassis base pressure sensor under different access volttimes and pressures, analyzed its sensitivity and other performance, and compared the above performance with the rectangular monocrystalline silicon chassis base pressure sensor. The experimental results show that the circular monocrystalline silicon chassis pressure sensor has excellent electrostriction performance, and the variation of the potential and potential difference in the measuring area is more obvious than that of the rectangular monocrystalline silicon chassis pressure sensor. This paper provides a reference for sensor makers.
Impact of Battery Capacity and Charging-Discharging Cycles on the Performance of Communication Devices
Authors: Tao Jiaju , Qian Song , Yang Junfei
Published: July 2024

This study investigates the crucial role of battery capacity and charging-discharging cycles in determining the performance of communication devices, especially electric vehicles (EVs). Given the multifaceted factors affecting battery performance, including type, specification, and environmental conditions, it becomes essential to develop a robust method for modeling and analyzing battery behavior under various scenarios. Our research introduces a novel approach that amalgamates machine learning and optimization techniques to comprehensively model and analyze battery performance. Utilizing real-world data from an EV fleet, we validate our method against existing models, demonstrating superior accuracy, efficiency, and robustness. The findings reveal our method’s effectiveness in optimizing communication devices’ performance metrics, such as efficiency, cost, and reliability, by accurately capturing the nonlinear and dynamic relationships between battery capacity and usage cycles. Our conclusion underscores the potential of this method in enhancing the management and optimization of communication devices, paving the way for more sustainable and efficient use of battery technology in EVs.
Design of a Portable Emergency DC Power Supply
Authors: Wang Xin
Published: July 2024

In recent years, wireless or handheld devices have become increasingly widely used, especially in areas such as environmental monitoring and the Internet of Things. However, due to environmental conditions, they cannot rely on the power grid to provide electricity, and energy supply has become a key issue that restricts the deployment and operation of such devices. This article introduces the method and principle of applying a microcontroller control system to a portable emergency DC power supply, and proposes a method for a portable emergency DC power supply with adjustable and stable output. The output voltage can be adjusted in steps of 0.1-15V. This adjustable portable emergency DC power supply not only has the advantages of small volume and low loss of switch mode power supply, but also has the advantages of small output voltage ripple and good output characteristics of linear power supply. It has certain research significance and practical value.
A Precise Temperature Control Method for Lithium-ion Battery Pack based on the Nonlinear Model Predictive Control Algorithm
Authors: Wen Zhihao , Wei Yalin
Published: July 2024

To utilize the maximum performance of the battery while ensuring its thermal safety, a battery thermal management system is used to control the battery maximum temperature within a safe range. This paper centres on the establishment of a temperature prediction model and the development of the nonlinear-based model predictive control (MPC) strategy. First, to address the need of predicting battery temperature, this paper develops a distributed parameter thermal resistance model to predict battery temperature quickly and accurately. Secondly, the open-loop formulation of the nonlinear-based MPC is derived based on the established state space equations. Then the soft and hard constraints of the model are established based on the actual current conditions, pump conditions, temperature difference and temperature rise indexes, so as to establish the objective function of the MPC algorithm. Finally, the established temperature nonlinear MPC algorithm is embedded on the board and the hardware platform of battery liquid cooling system is established. The experiment test result shows that the maximum error of temperature control is less than 0.1°C, and the effectiveness of the temperature control strategy of lithium-ion battery is verified through experiments.
Design of a High Frequency Stability Control Algorithm for Flexible DC Systems
Authors: An Rui , Wei Mengyang , Zhao Jinlong , Yang Junhui , Li Hongbo
Published: July 2024

The suppression scheme of flexible DC high-frequency oscillation needs to be based on model construction. Related literatures have established a high-order linearization model of converter station, gradually revealing the influence of control system and its parameters on impedance characteristics. In order to ensure the full utilization of renewable energy, it is necessary to deeply study the interaction characteristics between multi-terminal VSC-HVDC (Voltage Source Converter based High Voltage Direct Current Transmission) and the receiving power grid, and design a grid-friendly control strategy. In this paper, a VSC-HVDC high-frequency stability control algorithm is established, and a double-ended VSC-HVDC bidirectional VSC stable switching controller is constructed. The switching sequence generated by the controller replaces the control sequence generated by the previous PWM (Pulse width modulation) modulation, so as to weaken the influence of the inner loop current control parameters on the stable operation of the system. The simulation results show that the reactive power fluctuation amplitude of PI control on the inverter side is 0.031 p.u, and the stabilization time is 0.43s. The reactive power fluctuation amplitude of bidirectional VSC stable switching control is less than 0.012 p.u, and the stability time is less than 0.2s. When the single-phase grounding wire is short-circuited, the bidirectional VSC regulator switch has better control performance than the PI regulator switch. Compared with the traditional PI controller, the proposed controller has better stability. The system can quickly enter a stable and non-overshoot operation state, and achieved good control effect.
Synthesis and Characterization of NiCo2S4-MOF-ZIF-67@rGO for Efficient Electrochemical Energy Storage
Authors: Antony Sakthi S. , Priyadarshini K. , Mani C. , Rusho Robin Prasad S. , Dominic A.
Published: July 2024

A nanocomposite, NiCo2S4-MOF-ZIF-67@reduced grapheme oxide was produced via a straightforward and scalable hydrothermal process. The product nanocomposite was characterized using different techniques including Infra red spectroscopy, X-ray diffraction analysis, scanning electron microscopy and electrochemical measurements. This nanocomposite was found to be composed of NiCo2S4 nanoparticles embedded in a MOF-ZIF-67 matrix, which was anchored onto rGO sheets. The NiCo2S4-MOF-ZIF-67@rGO nanocomposite exhibited excellent electrochemical performances. These properties make the NiCo2S4-MOF-ZIF-67@rGO nanocomposite a potential electrode substance in the case of electric energy accumulators and conversion devices such as primary and rechargeable Li cells and high performance ultra-capacitors. The simple and scalable synthesis method used in this study also suggests that this material has potential for large-scale production.
A Facile Synthesis and Characterisation of CdS Nanoparticles at Low Temperature Using Aegle Marmelos Extract
Authors: Rajkumar Thirunavukkarasu , Venkateswaran Lakshmy , Thirunavukkarasu Somanathan , Rangasamy Sasieekhumar Amman
Published: July 2024

CdS NPs have become found applications across diverse domains in the field of nanobiotechnology because of their established biomedical characteristics. The dimensions and the materials used for coating CdS NPs are pivotal factors influencing their effectiveness in biomedical applications like cancer treatment, bacterial inhibition, bioimaging and biosensors. In this study, we succesfully produced CdS NPs by ecofriendly approach using aegle marmelos extract. The synthesized CdS NPs was subjected to characterization using X-Ray Diffraction spectroscopy (XRD), Ultraviolet-Visible spectroscopy (UV-VIS), Fourier Transform Infrared spectroscopy (FT-IR), Dynamic Light Scattering (DLS), Scanning Electron Microscope (SEM) with EDX and Transmission Electron Microscope (TEM). The research delineates a straightforward, economically viable environmentally friendly approach to synthesizing CdS nanoparticles, which is suitable for extensive production. Additionally, it presents a tactic to regulate both the size and distribution of nanoparticles using eco-friendly biomolecules, enhancing their potential for various applications. Based on the results obtained from the characterization studies, it was proposed to the further process for biological applications.
Fabrication of europium substituted hydroxyapatite coating on polyindole-5-carboxylic acid coated titanium for bone implant applications
Authors: Ramya S. , Nilufer A. , Saravanakumar P. , Kavitha L. , Shinyjoy E.
Published: July 2024

In the present study we account on the fabrication of duplex layer (Europium substituted hydroxyapatite (Eu-HAP) and Polyindole-5-carboxylic acid (PICA)) coatings on Ti by electrochemical technique. The as fabricated coatings were characterized for its functional groups and morphology by Fourier Transform Infrared Spectroscopy (FT-IR) and scanning electron microscopic (SEM) techniques, respectively. The corrosion resistance performance (i.e., bioresistivity) of the coatings was evaluated by electrochemical characterizations. Further, the biocompatibility of the coatings was characterized by in vitro antibacterial and cell viability. Thus, the as-developed Eu-HAP/PICA duplex coating will be a prospective and promising material for bone implant applications.
Growth of Helical Coiled Double and Triple Walled Carbon Nanotubes at Low Temperature using FeMoMgO catalyst
Authors: Manikandan Dhanavel , Somanathan Thirunavukkarasu
Published: July 2024

Helical coiled double and triple walled carbon nanotubes (CNTS) were synthesized using chemical vapor deposition (CVD) method using FeMoMgO catalyst. The FeMoMgO catalyst was prepared using combustion process followed by multi walled CNTs synthesize. The final products were characterized by X-Ray diffraction (XRD), FT-IR, SEM, TEM and FESEM (surface morphology) along with electron dispersion X-ray spectrometer (EDX). The XRD results show that Fe is well incorporated with Mg which indicates crystalline in nature. FT-IR, results confirm the presence of functional group and metal ion. FESEM indicates the formation of larger and non-uniform particles with higher active sites. SEM and TEM results show that at low temperature coiled CNTs were formed with 2-5nm in diameter. In conclusion that Helical coiled double and triple walled CNTs were synthesized using FeMoMgO Catalyst at low temperature.
Synthesis of MgAl2O4/gC3N4 nanocomposite and evaluation of their antioxidant properties by FRAP assay
Authors: Nitha T.V. , Britto S.
Published: July 2024

In this study, MgAl2O4/gC3N4 composite material was successfully synthesized by the impregnation method and characterized by XRD, SEM, EDAX, and UV-visible analysis. The structural properties of the material are obtained from XRD analysis, and the optical properties are investigated by a UV-visible study. The morphological characteristics and compositional analysis of the nanomaterial are studied by SEM with EDAX spectra. The antioxidant activity of the material was examined through a FRAP assay, and the results show it has 90% activity.