bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling of Resistance Spot Welding Using FEM
Authors: Al Sarraf Ziad 
Published: October 2023

The resistance spot welding process is significant for joining materials in the automotive industry because it offers high speed and can be easily automated. Recently, there has been a demand in the automotive industry to reduce vehicle weight to improve fuel efficiency. Aluminium alloys are considered a viable alternative for auto-body materials to meet this requirement. It not only helps enhance fuel efficiency but also addresses the issue of vehicle corrosion. However, joining aluminium through resistance spot welding presents serious challenges compared to steel. One significant difficulty arises from the faster deterioration of electrodes. Aluminium alloys possess high electrical and thermal conductivity, significant shrinkage during solidification, and a natural oxide coating. These features make the spot welding process for aluminium alloys notably distinct. When exposed to high temperatures, aluminium undergoes a chemical reaction with the copper alloy found in the electrode material. This results in the unpredictable removal of material from the electrode surfaces, causing wear and significantly reducing the lifespan of the electrode during spot welding of aluminium alloys. This decrease in electrode tip longevity poses a significant drawback in weldability, as the durability of the electrode tip significantly affects its suitability for automotive applications.
Due to the rapid nature of the process, obtaining crucial information, such as the transient distribution of current density and temperature through experimental methods, becomes challenging. Therefore, this study aims to develop an integrated computer simulation model using the finite element method to analyze the resistance spot welding process of aluminium alloys. Multiple calculations were performed considering different welding currents, weld times, electrode forces, and various surface conditions of the aluminium sheets. The simulation considers the nonlinear, temperature-dependent, thermo-physical properties of the materials. Interestingly, it was observed that in most cases, the nugget diameter is formed within a short time frame of 0.02 to 0.04 seconds, and further application of welding current primarily increases the heating of the electrode face. Moreover, the aluminium sheets’ initial surface condition significantly influences the nugget’s formation. Several other conclusions have been drawn as a result of this study.
The Inhomogeneity Effect. II. Rotational and Orbital States Impact Planetary Cooling
Authors: Zhang Xi 
Published: October 2023

Abstract
We generalize the theory of the inhomogeneity effect to enable comparison among different inhomogeneous planets. A metric of inhomogeneity based on the cumulative distribution function is applied to investigate the dependence of planetary cooling on previously overlooked parameters. The mean surface temperature of airless planets increases with rotational rate and surface thermal inertia, which bounds the value in the tidally locked configuration and the equilibrium temperature. Using an analytical model, we demonstrate that the internal heat flux of giant planets exhibits significant spatial variability, primarily emitted from the nightside and high-latitude regions acting as radiator fins. Given a horizontally uniform interior temperature in the convective zone, the outgoing internal flux increases up to several folds as the inhomogeneity of the incoming stellar flux increases. The enhancement decreases with increasing heat redistribution through planetary dynamics or rotation. The outgoing internal flux on rapidly rotating planets generally increases with planetary obliquity and orbital eccentricity. The radiative timescale and true anomaly of the vernal equinox also play significant roles. If the radiative timescale is long, the outgoing internal flux shows a slightly decreasing but nonlinear trend with obliquity. Our findings indicate that rotational and orbital states greatly influence the cooling of planets and impact the interior evolution of giant planets, particularly for tidally locked planets and planets with high eccentricity and obliquity (such as Uranus), as well as the spatial and temporal variations of their cooling fluxes.
The Inhomogeneity Effect. I. Inhomogeneous Surface and Atmosphere Accelerate Planetary Cooling
Authors: Zhang Xi 
Published: October 2023

Abstract
We propose a general principle that under radiative-convective equilibrium, the spatial and temporal variations in a planet’s surface and atmosphere tend to increase its cooling. This principle is based on Jensen’s inequality and the curvature of the response functions of surface temperature and outgoing cooling flux to changes in incoming stellar flux and atmospheric opacity. We use an analytical model to demonstrate that this principle holds for various planet types: (1) on an airless planet, the mean surface temperature is lower than its equilibrium temperature; (2) on terrestrial planets with atmospheres, the inhomogeneity of incoming stellar flux and atmospheric opacity reduces the mean surface temperature; (3) on giant planets, inhomogeneously distributed stellar flux and atmospheric opacity increase the outgoing infrared flux, cooling the interior. Although the inhomogeneity of visible opacity might sometimes heat the atmosphere, the effect is generally much smaller than the inhomogeneous cooling effect of infrared opacity. Compared with the homogeneous case, the mean surface temperature on inhomogeneous terrestrial planets can decrease by more than 20%, and the internal heat flux on giant planets can increase by over an order of magnitude. Despite simplifications in our analytical framework, the effect of stellar flux inhomogeneity appears to be robust, while further research is needed to fully understand the effects of opacity inhomogeneity in more realistic situations. This principle impacts our understanding of planetary habitability and the evolution of giant planets using low-resolution and one-dimensional frameworks that may have previously overlooked the role of inhomogeneity.
Investigating the Magnetic Structure of Interplanetary Coronal Mass Ejections Using Simultaneous Multispacecraft In Situ Measurements
Authors: Regnault F. , Al-Haddad N. , Lugaz N. , Farrugia C. J. , Yu W. , Davies E. E. , Galvin A. B. , Zhuang B. 
Published: October 2023

Abstract
In situ measurements from spacecraft typically provide a time series at a single location through coronal mass ejections (CMEs), and they have been one of the main methods to investigate CMEs. The CME properties derived from these in situ measurements are affected by temporal changes that occur as the CME passes over the spacecraft, such as radial expansion and aging, as well as spatial variations within a CME. This study uses multispacecraft measurements of the same CME at close separations to investigate both the spatial variability (how different a CME profile is when probed by two spacecraft close to each other) and the so-called aging effect (the effect of the time evolution on in situ properties). We compile a database of 19 events from the past 4 decades measured by two spacecraft with a radial separation of <0.2 au and an angular separation of <10°. We find that the average magnetic field strength measured by the two spacecraft differs by 18% of the typical average value, which highlights nonnegligible spatial or temporal variations. For one particular event, measurements taken by the two spacecraft allow us to quantify and significantly reduce the aging effect to estimate the asymmetry of the magnetic field strength profile. This study reveals that single-spacecraft time series near 1 au can be strongly affected by aging and that correcting for self-similar expansion does not capture the whole aging effect.
Galactic Diffuse γ-Ray Emission from GeV to PeV Energies in Light of Up-to-date Cosmic-Ray Measurements
Authors: Zhang Rui , Huang Xiaoyuan , Xu Zhi-Hui , Zhao Shiping , Yuan Qiang 
Published: October 2023

Abstract
Diffuse γ-ray emission between 10 and 1000 TeV from the Galactic plane was recently measured by the Large High Altitude Air Shower Observatory (LHAASO). These observations will help tremendously in constraining the propagation and interaction of cosmic rays in the Milky Way. Additionally, new measurements of cosmic-ray spectra reach a very high precision of up to 100 TeV energies, revealing multiple spectral structures of various species. In this work, based on up-to-date measurements of local cosmic-ray spectra and a simplified propagation setup, we confront a model prediction of diffuse γ-ray emission with measurements of diffuse γ-rays. To better constrain the low-energy part of the model, we analyze the 14.6 yr of Fermi Large Area Telescope (Fermi-LAT) data to extract the Galactic diffuse emission between 1 and 500 GeV from the same sky regions of LHAASO, after subtracting the contribution from known sources and the isotropic diffuse γ-ray background. The joint Fermi-LAT and LHAASO spectra thus cover a very wide energy range from 1 GeV to 1 PeV with small gaps from 0.5 to 10 TeV. Compared with the prediction, we find that clear excesses between several GeV and ∼60 TeV of the diffuse emission exist. Possible reasons to explain the excesses may include unresolved sources or more complicated propagation models. We illustrate that an exponential cutoff power-law component with an index of −2.40 and a cutoff energy of ∼30 TeV is able to account for such excesses.
Simultaneous Observation of the Inner and Outer Electron Diffusion Region in Reconnection with Large Guide Field
Authors: Tian Z. C. , Zhou M. , Man H. Y. , Zhong Z. H. , Deng X. H. , Gershman D. J. , Khotyaintsev Y. V. , Russell C. T. 
Published: October 2023

Abstract
This paper presents a simultaneous observation of the inner and outer electron diffusion region (EDR) at the dayside magnetopause by the magnetospheric multiscale (MMS) spacecraft. The EDR was observed in magnetic reconnection with a large guide field. The inner EDR was characterized by positive

J
·

E

′

while the outer EDR is manifested by negative

J
·

E

′

and opposite out-of-plane electric field to that in the inner EDR. One pair of the spacecraft detected the inner EDR while the other pair encountered the outer EDR. Moreover, the two pairs were on the opposite side of the X-line as they observed the bidirectional accelerated electron jets. The fortuitous formation of MMS allows us to estimate the maximum length of the inner EDR as ∼36 d

e
and the lower bound of the reconnection rate as 0.142 ± 0.041. These observations have far-reaching implications for understanding the electron physics in reconnection.
Decomposing the Origin of TeV–PeV Emission from the Galactic Plane: Implications of Multimessenger Observations
Authors: Fang Ke , Murase Kohta 
Published: October 2023

Abstract
High-energy neutrino and γ-ray emission has been observed from the Galactic plane, which may come from individual sources and/or diffuse cosmic rays. We evaluate the contribution of these two components through the multimessenger connection between neutrinos and γ-rays in hadronic interactions. We derive maximum fluxes of neutrino emission from the Galactic plane using γ-ray catalogs, including 4FGL, HGPS, 3HWC, and 1LHAASO, and measurements of the Galactic diffuse emission by Tibet ASγ and LHAASO. We find that the IceCube Galactic neutrino flux is larger than the contribution from all resolved sources when excluding promising leptonic sources such as pulsars, pulsar wind nebulae, and TeV halos. Our result indicates that the Galactic neutrino emission is likely dominated by the diffuse emission by the cosmic-ray sea and unresolved hadronic γ-ray sources. In addition, the IceCube flux is comparable to the sum of the flux of nonpulsar sources and the LHAASO diffuse emission especially above ∼30 TeV. This implies that the LHAASO diffuse emission may dominantly originate from hadronic interactions, either as the truly diffuse emission or unresolved hadronic emitters. Future observations of neutrino telescopes and air-shower γ-ray experiments in the Southern hemisphere are needed to accurately disentangle the source and diffuse emission of the Milky Way.
Pavo: Discovery of a Star-forming Dwarf Galaxy Just Outside the Local Group*
Authors: Jones Michael G. , Mutlu-Pakdil Burçin , Sand David J. , Donnerstein Richard , Crnojević Denija , Bennet Paul , Fielder Catherine E. , Karunakaran Ananthan , Spekkens Kristine , Strader Jay , Urquhart Ryan , Zaritsky Dennis 
Published: October 2023

Abstract
We report the discovery of Pavo, a faint (M

V
= −10.0), star-forming, irregular, and extremely isolated dwarf galaxy at D ≈ 2 Mpc. Pavo was identified in Dark Energy Camera Legacy Survey imaging via a novel approach that combines low surface brightness galaxy search algorithms and machine-learning candidate classifications. Follow-up imaging with the Inamori-Magellan Areal Camera and Spectrograph on the 6.5 m Magellan Baade telescope revealed a color–magnitude diagram (CMD) with an old stellar population, in addition to the young population that dominates the integrated light, and a tip of the red giant branch distance estimate of

1.99

−
0.22

+
0.20

Mpc. The blue population of stars in the CMD is consistent with the youngest stars having formed no later than 150 Myr ago. We also detected no Hα emission with SOAR telescope imaging, suggesting that we may be witnessing a temporary low in Pavo’s star formation. We estimate the total stellar mass of Pavo to be

log

M

*

/

M

⊙

=
5.6
±
0.2

and measure an upper limit on its H i gas mass of 1.0 × 106
M
⊙ based on the HIPASS survey. Given these properties, Pavo’s closest analog is Leo P (D = 1.6 Mpc), previously the only known isolated, star-forming, Local Volume dwarf galaxy in this mass range. However, Pavo appears to be even more isolated, with no other known galaxy residing within over 600 kpc. As surveys and search techniques continue to improve, we anticipate an entire population of analogous objects being detected just outside the Local Group.
UNCOVER: A NIRSpec Identification of a Broad-line AGN at z = 8.50
Authors: Kokorev Vasily , Fujimoto Seiji , Labbe Ivo , Greene Jenny E. , Bezanson Rachel , Dayal Pratika , Nelson Erica J. , Atek Hakim , Brammer Gabriel , Caputi Karina I. , Chemerynska Iryna , Cutler Sam E. , Feldmann Robert , Fudamoto Yoshinobu , Furtak Lukas J. , Goulding Andy D. , de Graaff Anna , Leja Joel , Marchesini Danilo , Miller Tim B. , Nanayakkara Themiya , Oesch Pascal A. , Pan Richard , Price Sedona H. , Setton David J. , Smit Renske , Stefanon Mauro , Wang 王 Bingjie 冰洁 , Weaver John R. , Whitaker Katherine E. , Williams Christina C. , Zitrin Adi 
Published: October 2023

Abstract
Deep observations with the James Webb Space Telescope (JWST) have revealed an emerging population of red pointlike sources that could provide a link between the postulated supermassive black hole seeds and observed quasars. In this work, we present a JWST/NIRSpec spectrum from the JWST Cycle 1 UNCOVER Treasury survey of a massive accreting black hole at z = 8.50 displaying a clear broad-line component as inferred from the Hβ line with FWHM = 3439 ± 413 km s−1, typical of the broad-line region of an active galactic nucleus (AGN). The AGN nature of this object is further supported by high ionization, as inferred from emission lines, and a point-source morphology. We compute a black hole mass of

log

10

(

M

BH

/

M

⊙

)
=
8.17
±
0.42

and a bolometric luminosity of L
bol ∼ 6.6 × 1045 erg s−1. These values imply that our object is accreting at ∼40% of the Eddington limit. Detailed modeling of the spectral energy distribution in the optical and near-infrared, together with constraints from ALMA, indicate an upper limit on the stellar mass of

log

10

(

M

*

/

M

⊙

)
<
8.7

, which would lead to an unprecedented ratio of black hole to host mass of at least ∼30%. This is orders of magnitude higher compared to the local QSOs but consistent with recent AGN studies at high redshift with JWST. This finding suggests that a nonnegligible fraction of supermassive black holes either started out from massive seeds and/or grew at a super-Eddington rate at high redshift. Given the predicted number densities of high-z faint AGN, future NIRSpec observations of larger samples will allow us to further investigate galaxy–black hole coevolution in the early Universe.
Gaia Astrometry and MIKE+PFS Doppler Data Joint Analysis Reveals that HD 175167b is a Massive Cold Jupiter
Authors: Gan Tianjun 
Published: October 2023

Abstract
HD 175167b is a cold (P

b
∼ 1200 days) Jupiter with a minimum mass of

M

p

sin

i
=
7.8
±
3.5

M

J

orbiting a Sun-like star, first discovered by the Magellan Planet Search Program based on MIKE observations. Through a joint analysis of the MIKE data and the Gaia two-body orbital solution, Winn found a companion mass of M

p
= 14.8 ± 1.8 M

J
and suggested that it might be better designated as a brown dwarf. Additional publicly available radial velocity data from Magellan/PFS better constrains the model, and reveals that the companion is a massive cold Jupiter with a mass of M

p
= 10.2 ± 0.4 M

J
and a period of P

b
= 1275.8 ± 0.4 days. The planet orbit is inclined by i = 38.°6 ± 1.°7 with an eccentricity of 0.529 ± 0.002.
Study on the Importance of Including Concepts Related to Value Education in the Grade Six Western Music Sri Lankan School Curriculum
Authors: Kumara G.S.G. Wasantha 
Published: October 2023

A perfect person is not born at birth. Just as we learn mathematics and languages, we should also become specialists in those lessons that are fundamental to living in harmony and social progress, such as respect, empathy, equality, solidarity, and critical thinking. Without these and other ethical principles that define us as human beings, it will be difficult for us to build a better world.
Value education, therefore, promotes tolerance and understanding above and beyond our political, cultural, and religious differences, putting special emphasis on the defense of human rights, the protection of ethnic minorities and the most vulnerable groups, and the conservation of the environment. Developing value education in students is the primary responsibility of all stakeholders, and it is not the sole responsibility of each school. It is the collective responsibility of the family, schools, universities, businesses, and sports associations to provide all the ideal contexts to teach those ethical principles.
Teachers and students are directly involved in the learning-teaching process of the school system according to the curriculum designed for the school system by the Education Ministry of Sri Lanka. Teachers must have a good understanding of the syllabi relevant to any subject and have a good understanding of school children. Teachers should comprehend their learners’ needs, tastes emotions, possibilities, aspirations, and mental and psychological capacities. Therefore, teachers are the major contributors among the key parties who make any changes and developments in the curriculum. Teachers have a vast body of knowledge and experience about the knowledge, skills, and attitudes to be taught to children through the curriculum, as well as concepts and skills related to good personal and social habits, and it is important to look into that when the curriculum is reformed.
All these malpractices occurred because of the lack of knowledge of religious, moral and education values. Therefore, it is the foremost duty of each and every citizen of Sri Lanka to promote and rebuild value education. As such, this study may help to promote and develop a specific value education in the school system of Sri Lanka.
If students do not learn good values through education, they will have to face various problems not only in school but also in society. The incorporation of value concepts into the school curriculum may be a solution to resolve this situation. When designing curricular, one needs to ask such questions such as, how should value concepts be included in the curriculum? What are the values that should be taught in the current curriculum? Failure to ask teachers about the inclusion of value concepts into the school curriculum can lead to several practical problems in the learning-teaching process.
Changing Pattern of Antifungal Drug Resistance in a Tertiary Health-care Facility – A Cross-sectional Study
Authors: Sahu Satabdi , Panda Abinash , Dash Suryasnata , Ramani Y. Roja , Behera Jayanti Prava 
Published: October 2023

Background:
Fungal infections remain a major source of morbidity and mortality, but treatment choices are restricted due to limited classes of antifungal agents. The emergence of antifungal drug resistance (AFDR) is a major concern. Understanding trend in the development of AFDR will facilitate the use of therapeutic strategies to overcome and prevent antifungal resistance. The primary objective of the present study was to find out the pattern of AFDR in laboratory-confirmed mycological culture isolates.

Methodology:
The record-based cross-sectional study was carried out to analyze all the mycological culture sensitivity reports during a period of 3 years. The data set included clinicodemographic parameters such as age, gender, provisional diagnosis, type of culture specimens, identified fungal isolate, and susceptibility pattern. The association between the selected parameters and the pattern of AFDR was found out by Pearson's Chi-squared test.

Results:
AFDR among the isolates was 22 (75.86%), 8 (61.54%), 25 (100%), and 7 (70%) during the period from 2019 to 2022. The rate of AFDR was 33.87% during the study period. Antifungal susceptibility testing showed a rising trend in fluconazole resistance from 2019 (27.2%) to 2022 (57.1%). AFDR was highest in the age group of 41–60 years (48.3%), in males (72.5%), in skin scrapings (40.3%), and in cases with a provisional diagnosis of deep mycosis (51.6% in deep mycosis vs. 46.7% in superficial mycosis). The association between age, type of clinical specimen, type of mycosis, and occurrence of AFDR was statistically significant (P ≤ 0.05). The most common fungal specimen isolated was Candida
albicans whereas the highest prevalence of AFDR was observed among Candida
glabrata.

Conclusion:
In all the clinical conditions (superficial and deep mycosis), resistance to fluconazole was the predominant type of AFDR. There was a rising trend in the resistance pattern to fluconazole which is one of the most commonly used antifungal agents.