bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical characteristics of Ni50Co50/Ni substrate during indentation by molecular dynamics
Authors: Pham Anh-Vu , Fang Te-Hua , Nguyen Van-Thuc , Chen Tao-Hsing 
Published: March 2022

Abstract
Coating an alloys film onto a metallic surface could dramatically improve the surface quality. This report studies the microstructure and intermixing phenomena of Ni50Co50 film deposited on Ni(001) substrate with flat, asperity and trench Ni surfaces by molecular dynamics (MD) simulation. The effects of the film thickness and loading velocity on the mechanical properties and deformation behaviours of the sample are also surveyed by indentation. The results represent that the intermixing and lattice structure of the film is enhanced after annealing. Moreover, the sample hardness is improved as the deposited Ni50Co50 film when the film thickness rising from 18 to 38 Å. In contrast, the structure transformation rate and dislocations density of the sample decrease when the Ni50Co50 film becomes thicker. Interestingly, the plastic deformation rate and dislocation density of the sample at the trench surface are higher than the flat one. Besides, the increase of the loading velocity gives rise to the plastic deformation and the local stress rates. The dislocation density of the Ni50Co50/Ni sample is reduced if the loading speed is high enough.
Power law fitting of the ion saturation current and the three-temperature Maxwellian EEDF in a multi-dipole confined hot cathode discharge: an experimental revisitation
Authors: Yip Chi-Shung , Jin Chenyao , Zhang Wei , Jiang Di , Xu Guo-Sheng 
Published: March 2022

Abstract
Langmuir probe diagnostic in a multi-dipole confined hot cathode discharge has been revisited with an improved sheath expansion model with fitted expansion parameters. The results show a three-temperature Maxwellian EEDF composition also observed in previous studies using a very similar system. The dependence on neutral pressure and discharge current of each electron species are consistent with known physical processes in a multi-dipole confined hot cathode discharge. This shows that the employment of the new ion saturation fitting method does not eliminate the contribution of the high energy degraded primaries to the Langmuir probe I–V trace, as sheath expansion and high energy electron current contributes differently on an I–V trace. The result remains supportive to the existence of a very hot (T
dp > 15 eV) degraded primary electron species separate from the typical hot electron (T
hot ∼ 3 eV) species. Thus it is recommended to sweep the Langmuir probe beyond the bias voltage of the hot cathode, whenever possible, in order to properly resolve the contribution to the I–V trace of the degraded primaries.
Self-sensing magnetostrictive actuator based on ΔE effect: design, theoretical modeling and experiment
Authors: Xie Dongjian , Yang Yikun , Yang Bintang 
Published: March 2022

Abstract
Giant magnetostrictive material (GMM) has the smart potential to be integrated as a self-sensing actuator. This paper presents a novel self-sensing giant magnetostrictive actuator (SSGMA), by sensing the on-line stiffness of the actuator upon the ΔE effect. A self-sensing signal is generated by superimposing a set of high-frequency small sensing excitation magnetic fields on low-frequency static or quasi-static driving magnetic fields. The fully coupled magneto-elastic-thermal nonlinear constitutive model of GMM is derived, and then the self-sensing response model of the SSGMA based on the nonlinear equivalent piezomagnetic equation is proposed. On the theoretical basis, the influences of magnetic field, prestress and temperature on the ΔE effect, the equivalent piezomagnetic equation parameters and the SSGMA sensing signal are investigated in detail, respectively. Moreover, a prototype of the SSGMA is fabricated and tested for self-sensing performance. The experimental results demonstrate the effectiveness of the theoretical analysis, and further show that the proposed SSGMA achieves self-sensing output displacement within a stroke of nearly 50 μm, with a sensitivity of 2.49 mV μm−1. The self-sensing displacement resolution of the SSGMA by far may reach 63.4 nm after experimental determination. This novel self-sensing actuator with micron-level self-sensing drive capability can be integrated into an external sensorless execution system in the future.
Input shaping for travelling wave generation
Authors: Bhayadia Amit , Olivett Anthony , Singh Tarunraj , Karami M Amin 
Published: March 2022

Abstract
Travelling wave patterns observed in the movement of certain aquatic animals has motivated research in the modification of flow behavior, especially to deal with boundary layer separation in airplane wings. Research has shown that inducing travelling waves on the top surface of the wing can generate sufficient momentum to prevent boundary layer separation without increasing the drag. Due to this effect of propagating waves on the aerodynamics, generation of travelling waves on solid surfaces is being widely studied. Recently, methods such as two-mode excitation, active sink and impedance matching have shown promise in generation of uniform travelling waves in solids with the help of piezo electric actuators. Unfortunately, there are some challenges involved in the experimental application of these methods. Although these techniques have shown to be adequate in laboratory settings, they require laborious tuning procedures which do not guarantee desired trajectories and are followed in light of interference from unwanted modes and their transients. Some methods rely on selective mode excitation, which can cause interference from unwanted modes if the transient behavior of the system is not accounted for. Feed-forward input shaping control methods are proposed that augment the open-loop piezo actuation method (two-mode excitation) and provide a more robust method for generating uniform travelling waves. The input shaping control alters the reference signal such that the parasitic behavior of unnecessary modes is cancelled out. The combination of the mode suppression and selective mode excitation through input shaping is verified experimentally for generation of a smooth travelling waves in finite structures.
Interaction of short wavelength photons with atomic and molecular ions: 50 years some examples
Authors: Kennedy Eugene T 
Published: March 2022

Abstract
Steve Manson has been involved with the study of the photoionisation of atomic ions since the early 70’s. Over the half century since, much has happened in terms of theory and experiment. This short paper provides some examples of the inner-shell photoionisation of atomic ions, which demonstrate different experimental approaches and the important ongoing symbiotic nature of combined theoretical and experimental studies. Recent initiatives in the study of the photoionisation of small molecular ions are also briefly described.
Cosmological perturbation theory in f(Q,T) gravity
Authors: Nájera Antonio , Fajardo Amanda 
Published: March 2022

Abstract
We developed the cosmological linear theory of perturbations for f(Q,T) gravity, which is an extension of symmetric teleparallel gravity, with Q the non-metricity and T the trace of the stress-energy tensor. By considering an ansatz of f(Q,T) = f
1(Q)+f
2(T), which has been broadly studied in the literature and the coincident gauge where the connection vanishes, we got equations consistent with f(Q) gravity when fT
= 0. In the case of the tensor perturbations, the propagation of gravitational waves was found to be identical to f(Q), as expected. For scalar perturbations, outside the limit fT
= 0, we got that the coupling between Q and T in the Lagrangian produces a coupling between the perturbation of the density and the pressure. This coupling is preserved when considering the weak coupling limit between Q and T. On the other hand, in the strong coupling limit with a generic function of the form f
2(T) = αT + β T
2, the perturbative equations are heavily driven by the f
2(T) derivatives when β ≠ 0. However, when β = 0, the perturbative equations are identical to the weak coupling limit even though this case is a non-minimally coupling one. The presence of T in the Lagrangian breaks the equation of the conservation of energy, which in turn breaks the standard ρ' + 3𝓗 (ρ+p) = 0 relation. We also derived a coupled system of differential equations between δ, the density contrast and v in the 𝓗 ≪ k limit and with negligible time derivative of the scalar perturbation potentials, which will be useful in future studies to see whether this class of theories constitute a good alternative to dark matter. These results might also enable to test f(Q,T) gravity with CMB and standard siren data that will help to determine if these models can reduce the Hubble constant tension and if they can constitute an alternative to the ΛCDM model.
Higher derivative scalar tensor theory in unitary gauge
Authors: Joshi Pawan , Panda Sukanta 
Published: March 2022

Abstract
Ostrogradsky instability generally appears in nondegenerate higher-order derivative theories and this issue can be resolved by removing any existing degeneracy present in such theories. We consider an action involving terms that are at most quadratic in second derivatives of the scalar field and non-minimally coupled with the curvature tensors. We perform a 3+1 decomposition of the Lagrangian to separate second-order time derivative terms from rest. This decomposition is useful for checking the degeneracy hidden in the Lagrangian and helps us find conditions under which Ostrogradsky instability does not appear. We show that our construction of Lagrangian resembles that of a GR-like theory for a particular case in the unitary gauge. As an example, we calculate the equation of motion for the flat FRW. We also write the action for open and closed cases, free from higher derivatives for a particular choice derived from imposing degeneracy conditions.
On the origin of red spirals: does assembly bias play a role?
Authors: Sarkar Suman , Pandey Biswajit , Das Apashanka 
Published: March 2022

Abstract
The formation of the red spirals is a puzzling issue in the
standard picture of galaxy formation and evolution. Most studies
attribute the colour of the red spirals to different environmental
effects. We analyze a volume limited sample from the SDSS to study
the roles of small-scale and large-scale environments on the colour
of spiral galaxies. We compare the star formation rate, stellar age
and stellar mass distributions of the red and blue spirals and find
statistically significant differences between them at 99.9%
confidence level. The red spirals inhabit significantly denser
regions than the blue spirals, explaining some of the observed
differences in their physical properties. However, the differences
persist in all types of environments, indicating that the local
density alone is not sufficient to explain the origin of the red
spirals. Using an information theoretic framework, we find a small
but non-zero mutual information between the colour of spiral
galaxies and their large-scale environment that are statistically
significant (99.9% confidence level) throughout the entire length
scale probed. Such correlations between the colour and the
large-scale environment of spiral galaxies may result from the
assembly bias. Thus both the local environment and the assembly bias
may play essential roles in forming the red spirals. The spiral
galaxies may have different assembly history across
all types of environments. We propose a picture where the
differences in the assembly history may produce
spiral galaxies with different cold gas content. Such a difference
would make some spirals more susceptible to quenching. In all
environments, the spirals with high cold gas content could delay the
quenching and maintain a blue colour, whereas the spirals with low
cold gas fractions would be easily quenched and become red.
HGCROC3: the front-end readout ASIC for the CMS High Granularity Calorimeter
Authors: Bouyjou F. , Bombardi G. , Dulucq F. , El Berni A. , Extier S. , Firlej M. , Fiutowski T. , Guilloux F. , Idzik M. , De La Taille C. , Marchioro A. , Molenda A. , Moron J. , Swientek K. , Thienpont D. , Vergine T. 
Published: March 2022

Abstract
For the CMS High Granularity Calorimeter (CE), the final version of the 72-channel front-end ASIC (HGCROC3) was submitted in December 2020. HGCROC3 includes low-noise/high-gain preamplifiers/shapers and a 10-bit 40 MHz successive approximation ADC (SAR-ADC) that provide the charge measurement over the linear range of the preamplifier. In the saturation range, a discriminator and a time-to-digital converter (TDC) provide the charge information from the time over threshold (ToT; 200 ns dynamic range, 50 ps binning). A fast discriminator and another TDC provide timing information to 25 ps accuracy. The chip embeds all necessary ancillary services: bandgap circuit, PLL, threshold DACs. We present the experimental results on the latest and final version (HGCROC3) received in April 2021.
Using snapshot measurements to identify high-emitting vehicles
Authors: Qiu Minghao , Borken-Kleefeld Jens 
Published: March 2022

Abstract
Policy makers have long been interested in detecting ‘high-emitters’, a supposedly small fraction of vehicles that make disproportionally large contributions to total fleet emissions. However, existing identification schemes often exclusively rely on snapshot measurements (i.e. emissions within less than a second), and thus simply identify vehicles with high instantaneous emissions, instead of vehicles with high average emissions over a driving period as regulated by emission standards. We design a comprehensive scheme to address this challenge by combining fleetwide remote sensing measurements with detailed second-by-second emission measurements from individual vehicles. We first determine the trip-average NO
x
emission rates of individual vehicles in a Euro-5 diesel fleet measured across European locations; this allows, second, to calculate the fraction and emission contributions of high-emitters based on trip-average emission. We demonstrate that the identification of high-emitters is quite uncertain as long as it is based on single snapshots only; but 80% of the high-emitters can be identified with over 75% precision with five or more repeated measurements of the same vehicle. Compared to the conventional detection schemes, our scheme can increase the identified high-emitters and associated emission reductions by over 140%. Our method is validated and shown to be superior to the conventional interpretation of snapshot measurements.
Intra-annual relationship between precipitation and forest disturbance in the African rainforest
Authors: Gou Yaqing , Balling Johannes , De Sy Veronique , Herold Martin , De Keersmaecker Wanda , Slagter Bart , Mullissa Adugna , Shang Xiaocheng , Reiche Johannes 
Published: March 2022

Abstract
Analysis of forest disturbance patterns in relation to precipitation seasonality is important for understanding African tropical forest dynamics under changing climate conditions and different levels of human activities. Newly available radar-based forest disturbance information now enables an investigation of the intra-annual relationship between precipitation and forest disturbance in a spatially and temporally explicit manner, especially in the tropics, where frequent cloud cover hinders the use of optical-based remote sensing products. In this study, we applied cross-correlation on monthly precipitation and forest disturbance time series for 2019 and 2020 at a 0.5° grid in the African rainforest. We used the magnitude of the correlation and time lag to assess the intra-annual relationship between precipitation and forest disturbance, and introduced accessibility proxies to analyse the spatial variation of the relationship. Results revealed that a significant negative correlation between forest disturbance and precipitation dominates the study region. We found that significant negative correlations appear on average closer to settlements with overall smaller variations in travel time to settlements compared to grid cells with non-significant and significant positive correlation. The magnitude of the negative correlation increases as the travel time to settlements increases, implying that forest disturbances in less accessible areas are more affected by precipitation seasonality and that in particular human-induced disturbance activities are predominantly carried out in the drier months. Few areas showed a significant positive correlation, mainly resulting from natural causes such as flooding. These new insights in the interaction between forest disturbance, precipitation and accessibility provide a step forward in understanding the complex interactions that underlie the complexity of forest loss patterns that we can increasingly capture with Earth Observation approaches. As such, they can support forest conservation and management in coping with climate change induced changes of precipitation patterns in African rainforest countries.
On electron propagation in triangular graphene quantum dots
Authors: Hrivnák Jiří , Motlochová Lenka 
Published: March 2022

Abstract
Tight-binding models of electron propagation in single-layer triangular graphene quantum dots with armchair and zigzag edges are developed. The electron hoppings to the nearest and next-to-nearest neighbours on the honeycomb lattice as well as interactions with the confining Dirichlet and Neumann walls are incorporated into the resulting tight-binding Hamiltonians. Associated to the irreducible crystallographic root system A
2, the armchair and zigzag honeycomb Weyl orbit functions together with the related discrete Fourier–Weyl transforms provide explicit exact forms of the electron wave functions and energy spectra. The electronic probability densities corresponding to the armchair and zigzag dots are evaluated and their contrasting behaviour exemplified.
Identifying High-risk Areas of Dengue by Meteorological factors in Thailand
Authors: Langkulsen Uma , Sakolnakhon Kamol Promsakha na 
Published: March 2022

Abstract
Dengue is a public health problem in Thailand. This study aimed to investigate the spatial distribution pattern and meteorological factors associated with dengue in the central region over the past 10 years. Dengue incidence and meteorological data were collected from 2007 to 2016. Geographical information system modeling was done to generate sub-district level risk map of dengue incidences, with five risk levels. The findings revealed that mean temperature, rainfall, relative humidity, and wind speed are important meteorological factors that influence component of dengue disease occurrence. The identified sub-district level risk estimates can be very useful in planning and executing dengue control in Thailand.
Modelling of Aromatic Sulfur Compounds Adsorption from Hydrocarbon Fuels by Biochar Based Adsorbent
Authors: Uzunova S , Minchev L , Uzunov I 
Published: March 2022

Abstract
In this work model fuel containing thiophene, benzothiophene and dibenzothiophene in different concentration combinations were treated with biochar. The quantity of total sulfur into the stock mixed solutions was below 1000 ppm. The adsorbent was prepared by pyrolysis of rice husks. The investigation aimed to use the method of multiple linear regression to derive a mathematical model, describing the adsorption of the three aromatic sulfur compounds from single and multi-component solutions of model fuel. The model describing the adsorption from multi-component solutions, based on the experimental results, has a correlation coefficient of 0.961. It reveals that the degree of desulfurization does not depend on the concentration of thiophene, but only on the concentrations of benzothiophene and dibenzothiophene in the fuel. The model can be used to predict the level of the adsorptive purification of the fuel if the content of benzothiophene and dibenzothiophene in it is known.
Recent Norwegian Research Relevant to Evacuation, Search and Rescue under Arctic Conditions
Authors: Gudmestad Ove T. 
Published: March 2022

Abstract
Marine traffic is increasing in the Arctic Region. As ice in the Arctic Region retracts, opportunities for the marine industry increase. This relates to the fishing industry, which is moving further into the Arctic Seas, the shipping industry, which is using the Northern Sea Route, particularly for transporting liquefied natural gas, and the cruise industry, which is transporting passengers to the last frontier on the globe. The question has been raised: Are the marine industry’s activities in the Arctic Region safe for people, the environment and assets? The International Maritime Organization’s (IMO) Polar Code, which came into force in 2017 sets requirements for ships and procedures, as well as for the competence of those involved. In particular, there have been uncertainties regarding how people on board a ship in distress can be saved should it be necessary to abandon ship. The question is of considerable concern in Norway, which is a main stakeholder in the Arctic Region, with the involvement/passage of many fishing, cargo and cruise vessels. Over several years, considerable research has therefore been carried out to review the status of safe operations in the Arctic Region and to identify methods to improve the safety of all involved in the Arctic maritime traffic. This paper presents a summary of recent Norwegian research relevant to safe evacuation, search and rescue under Arctic conditions. The summary includes the outcome of the Norwegian research programme, Sarinor, the SARex exercises carried out by the University of Stavanger, the Norwegian Coast Guard and the industrial company GMC (Stavanger) in 2016, 2017 and 2018, as well as follow-up research carried out later. Its implementation in the IMO is also discussed. Finally, thoughts on continuing the work to further improve safety are presented.
Anthropogenic Contamination of the Atoyac River, México
Authors: Estrada Rivera A. , Díaz Fonseca A. , Treviño Mora S. , García Suastegui W.A. , Castelán Vega R del C.  , Chávez Bravo E. , Zayas Pérez M.T , Morán Perales J.L. , Handal Silva A. 
Published: March 2022

Abstract
The Atoyac River that crosses Puebla-Tlaxcala in Mexico shows a severe state of contamination, however, this situation has been scarcely studied. The objective of this work was to evaluate the pollutants in the Atoyac River (physicochemical parameters, heavy metals and volatile solvents) in three areas that comprise the state of Puebla and Tlaxcala from samples collected in August 2019. The study areas were San Cristóbal Tepetlaxco Puebla (Zone 1), San Martín Texmelucan Puebla (Zone 2) and Villa Alta Tlaxcala (Zone 3). The results of the determination of the physicochemical parameters (Temperature, pH, Conductivity, Turbidity, COD, BOD5 and DO), heavy metals and volatile organic solvents reveal that Zone 1 represents the least contaminated area while Zone 3 has a critical contamination due to the presence of physicochemical values and concentrations of heavy metals and organic solvents that exceed the limits allowed by the Official Mexican Standards. Therefore, our results suggest that the Atoyac River is affected in a heterogeneous way. Observing the increase in pollution dramatically and progressively. Hence, it is urgent to generate information that serves as evidence to make recommendations to curb excessive industrial and municipal pollution, which can cause problems for the environment and health of the population.