bluuebunny/crossref_metadata_2025_split huggingface dataset:
Locally maximising orbits for the non-standard generating function of convex billiards and applications
Authors: Bialy Misha , Tsodikovich Daniel 
Published: February 2023

Abstract
Given an exact symplectic map T of a cylinder with a generating function H satisfying the so-called negative twist condition,

H

12

>
0

, we study the locally maximising orbits of T, that is, configurations which are local maxima of the action functional

∑
n

H
(

q
n

,

q

n
+
1

)

. We provide a necessary and sufficient condition for a configuration to be locally maximising. Using it, we consider a situation where T has two generating functions with respect to two different sets of symplectic coordinates. We suggest a simple geometric condition which guarantees that the set of locally maximising orbits with respect to both of these generating functions coincide. As the main application we show that the two generating functions for planar Birkhoff billiards satisfy this geometric condition. We apply it to get the following result: consider a centrally symmetric curve γ, for which the Birkhoff billiard map has a rotational invariant curve α of four-periodic orbits. We prove that a certain L
2-distance between γ and its ‘best approximating’ ellipse can be bounded from above in terms of the measure of the complement of the set filled by locally maximising orbits lying between α and the boundary of the phase cylinder. Moreover, this estimate is sharp, giving an effective version of a recent result on Birkhoff conjecture for centrally symmetric curves (Bialy and Mironov 2022 Ann. Math.
196 389–413). We also get a similar bound for arbitrary curves γ, that relates the measure of the complement of the set of locally maximising orbits with the L
2-distance between γ and its ‘best approximating’ circle.
A feasibility study on removing lipid deposition in atherosclerotic plaques with ultrasound-assisted laser ablation
Authors: Singh Rohit , Ebersole Koji C , Yang Xinmai 
Published: February 2023

AbstractObjective. Atherosclerosis is the buildup of fats, cholesterol, and other substances on the inner walls of arteries. It can affect arteries of heart, brain, arms, legs, pelvis and kidney, resulting in ischemic heart disease, carotid artery disease, peripheral artery disease and chronic kidney disease. Laser-based treatment techniques like laser atherectomy can be used to treat many common atherosclerostic diseases. However, the use of laser-based treatment remains limited due to the high risk of complications and low efficiency in removing atherosclerostic plaques as compared with other treatment methods. In this study, we developed a technology that used high intensity focused ultrasound to assist laser treatment in the removal of the lipid core of atherosclerotic plaques.Approach. The fundamental mechanism to disrupt atherosclerostic plaque was to enhance the mechanical effect of cavitation during laser/ultrasound therapy. To promote cavitation, spatiotemporally synchronized ultrasound bursts of 2% duty cycle at 0.5 MHz and nanosecond laser pulses at 532 nm wavelength were used. Experiments were first performed on pig belly fat samples to titrate ultrasound and laser parameters. Then, experiments were conducted on human plaque samples, where the lipid depositions of the plaques were targeted.Main results. Our results showed that fat tissue could be removed with an ultrasound peak negative pressure (PNP) of 2.45 MPa and a laser radiant exposure as low as 3.2 mJ mm−2. The lipid depositions on the atherosclerostic plaques were removed with laser radiant exposure of 16 mJ mm−2in synchronizing with an ultrasound PNP of 5.4 MPa. During all the experiments, laser-only and ultrasound-only control treatments at the same energy levels were not effective in removing the lipid.Significance. The results demonstrated that the addition of ultrasound could effectively reduce the needed laser power for atherosclerotic plaque removal, which will potentially improve treatment safety and efficiency of current laser therapies.
Applicability of LPBF for producing Cu-11Al-5Ni-4Fe wt.% with shape memory properties
Authors: Guerra C , Ramos-Grez J A , La Fé-Perdomo I , Castillo A , Walczak M 
Published: February 2023

Abstract
The Cu-11Al-5Ni-4Fe wt% alloy was consolidated by additive manufacturing (AM) to determine the method applicability for producing shape memory alloy. The alloy was researched through compressive stress in three conditions: commercial (COM) (cast), as-built (AB), and AB heat treated (quenched). The results demonstrated that the AB sample acquired a reasonable superelasticity (SE) at room temperature (∼4%), which was improved to 6% after quenching. The COM sample damping capacity was better at high temperatures (350 °C) due to slip system activation at low stress (near 600 MPa), which resulted in a higher deformation energy dissipation. Due to the residual stress and null slip activation, the AB samples showed low damping capacity and low permanent strain at any temperature; however, they showed greater degree of SE. The AM technique of laser powder bed fabrication is concluded to be a viable option for producing printed parts with SE and damping properties.
A DFT modulated analysis of manganese doped graphene nanoribbons as a potential material for sensing of highly toxic gases CO, PH3 and SbH3
Authors: R Jyoti , Chauhan Moondeep , Kashyap Rajiv , Singh Mehar , Choudhary B C , Sharma Ramesh K 
Published: February 2023

Abstract
A theoretical Density-functional theory (DFT) study has been carried out to explore the interaction of highly toxic gases carbon monoxide (CO), phosphine (PH3) and stibine (SbH3) with pristine (AGNR) and manganese (Mn) doped armchair graphene nanoribbon (AGNR-Mn). The adsorption behaviour of these gases has been analyzed by calculating the binding distance, adsorption energy (Eads), band structure, density of state spectrum, and current-voltage characteristics. In the case of AGNR, the highest Eads = −0.19 eV has been observed for the CO gas. The Mn doping leads to the high stability and substantial improvement in adsorption performance due to covalent interaction with gas molecules. The enhancement in adsorption energy by 19, 26 and 23 times for CO, PH3 and SbH3 respectively has been observed using AGNR-Mn instead of AGNR. The adsorption of these gases shows a considerable enhancement in the DOS around Fermi level. Furthermore, using I-V characteristics, the response of all these gases is observed and it has been found that the response of PH3 and SbH3 gas to AGNR-Mn are 48% and 45% respectively. These findings indicate that the AGNR-Mn system can be explored as a highly sensitive material for potential gas sensing of PH3 and SbH3.
High-speed Focal Plane Wave Front Sensing with an Optical Chopper
Authors: Gerard Benjamin L. , Dillon Daren , Cetre Sylvain , Jensen-Clem Rebecca 
Published: February 2023

Abstract
Focal plane wave front sensing and control is a critical approach to reducing noncommon path errors between a conventional astronomical adaptive optics (AO) wave front sensor (WFS) detector and a science camera. However, in addition to mitigating noncommon path errors, recent focal plane wave front sensing techniques have been developed to operate at speeds fast enough to enable “multi-WFS” AO, where residual atmospheric errors are further corrected by a focal plane WFS. Although a number of such techniques have been recently developed for coronagraphic imaging, here we present one designed for noncoronagraphic imaging. Utilizing conventional AO system components, this concept additionally requires (1) a detector imaging the focal plane of the WFS light source and (2) a pupil plane optical chopper device that is the noncommon path to the first WFS and is synchronized to the focal plane imager readout. These minimal hardware requirements enable the temporal amplitude modulation to resolve the sine ambiguity of even wave-front modes for low, mid, and high wave front spatial frequencies. Similar capabilities have been demonstrated with classical phase diversity by defocusing the detector, but such techniques are incompatible with simultaneous science observations. This optical chopping technique, however, enables science imaging at up to 50% duty cycle. We present both simulations and laboratory validation of this concept on SEAL, the Santa Cruz Extreme AO Laboratory testbed.
Magnetic island formation and rotation braking induced by low-Z impurity penetration in an EAST plasma
Authors: Zeng Shiyong , Zhu Ping , Zhou Ruijie , Xu Ming 
Published: February 2023

Abstract
Recent observations of the successive formations of the

4

/

1
,
3

/

1

, and

2

/

1

magnetic islands as well as the subsequent braking of the

2

/

1

mode during a low-Z impurity penetration process in EAST experiments are well reproduced in our 3D resistive MHD simulations. The enhanced parallel current perturbation induced by impurity radiation predominately contributes to the tearing mode growth, and the

2

/

1

island rotation is mainly damped by the impurity accumulation as results of the influence from high n modes.
Processing diagram for powder bed additive manufacturing
Authors: Koleva E , Kolev G , Koleva L 
Published: February 2023

Abstract
This paper presents the developed software for processing parameter simulation and optimization of powder bed additive manufacturing by concentrated energy beams. The simulations are realized by implementation of a normalized processing diagram and analytical model simulating heating of powder layers by a moving linear heat source. Their implementation is demonstrated for electron beam or laser additive manufacturing of industrial alloys. The developed software and the processing diagram provide a useful reference and methodology to support the selection of appropriate processing parameters during the early development stages of concrete powder bed additive manufacturing technology, building production digital twins or development of integrated process management system.
Atomic layer etching of nanowires using conventional reactive ion etching tool
Authors: Khan M B , Shakeel Sh , Richter K , Ghosh S , Erbe A , Georgiev Yo M 
Published: February 2023

Abstract
Innovative material and processing concepts are needed to further enhance the performance of complementary metal-oxide-semiconductor (CMOS) transistors-based circuits as the scaling limits are being reached. To supplement that, we report on the development of an atomic layer etching (ALE) process to fabricate small and smooth nanowires using a conventional dry etching tool. Firstly, a negative tone resist (hydrogen silsesquioxane) is spin-coated on Silicon Germanium-on-insulator (SiGeOI) samples and electron beam lithography is performed to create nanopatterns. These patterns act as an etch mask and are transferred into the SiGeOI layer using an inductively-coupled plasma reactive ion etching (ICP-RIE) process. Subsequently, an SF6 and Ar+ based ALE process is employed to smoothen the nanowires and reduce their widths. SF6 modifies the surface of the samples, while in the next step Ar+ removes the modified surface. To investigate the effect of this process on the nanowire width, several ALE cycles are performed. The etched features are inspected using scanning electron microscopy. With the increasing number of ALE cycles, a reduction in the width is observed. An etch per cycle of 1.1 Å is obtained.
A comprehensive study on the microstructure of plasma spraying coatings after electron beam remelting
Authors: St Węglowski M , Śliwiński P , Dymek S , Kalemba-Rec I , Kapuściński M , Wrona A , Kustra K 
Published: February 2023

Abstract
One of the most popular thermal spraying technology is atmospheric plasma spraying (APS). However, it should be noted, that numerous imperfections in the APS surface layers can be occurred. The porosity, microcracks as well as lamellar microstructure occurred. Moreover, the adhesion of the coating is limited. However, the reduction of porosity and other imperfections by remelting process can be eliminated. The laser or electron beams for remelting are the most popular technologies. Mainly, power of the beam and travelling speed influence on the thickness and the final properties of the remelted coatings. In the paper, the electron beam (EB) process for remelting of plasma spraying surface layers in relation to microstructure is presented. The Ni20%Cr + 30%Re APS coating on stainless steel substrate 316Ti grade by electron beam was remelted. The effect of remelting process on microstructure was presented. The light microscopy (LM) as well as scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS) for microstructure analysis of APS coatings after EB remelting were used. The results show that the APS coatings subjected EB remelted becomes much denser. Moreover, the porosity was reduced and the chemical composition of the coatings after remelting became homogeneous.
The quality improvement of welded joints of die-cast Al alloys using oscillation and current modulation of the electron beam
Authors: Drimal D , Kovac L , Sekerka R , Kasencak M 
Published: February 2023

Abstract
The issues of the difficult weldability of the high-pressure die-cast aluminum alloys - AlSi10Mg(Fe) were studied within the presented paper. The metallographic, CT, and EDX analyses of castings were performed to identify potential origins of weld joint imperfections and deteriorated weldability. A comparative welding test of welding gravitation die-cast alloys was accomplished to review the influence of the melting process on the weld quality. The casting process was analyzed and several mediums were evaluated as potential sources of material contamination. The selected contaminants were intentionally introduced into the weld joints. The research on welding process improvement and the reduction of the susceptibility to the presence of impurities was accomplished in the next step. The aim of the experiments was the use of dynamic deflection of the electron beam and pulse modulation of its power. The influence of different oscillation frequencies, amplitudes, and patterns was examined. The verified technology was developed, based on the achieved results.
Study of electron beam refining of metals by modelling of heat processes
Authors: Vutova K 
Published: February 2023

Abstract
The development and application of heat mathematical models and simulation tools, taking into account peculiarities of the investigated metals enable a more precise determination of the effect of the electron beam melting parameters (beam power, residence time, etc.) on the quality of the refined metal, to assess the relation between the processes and the material properties, as well as to formulate recommendations regarding the controlled parameters for increasing the efficiency of the technological e-beam melting and refining process. In this work, developed time-dependent simulation tool for heat transfer modeling at e-beam melting, aiming to aid understanding and optimizing electron beam refining process of metals materials, is applied for melting of different metals (tantalum, copper, and titanium). The model is validated using experimental data for the melted pool geometry and results are discussed.
Development of Asset Administration Shell for the components of EBMR plant
Authors: Ivanova T , Gocheva D , Batchkova I , Belev Y 
Published: February 2023

Abstract
The use of reference architectures and frameworks is an important prerequisite for dealing with the complexity, diversity and heterogeneity of cyber-physical systems. One of the most popular architectures is RAMI 4.0, suggested by the Industry 4.0 Working Group. According to RAMI 4.0, the Asset Administration Shell (AAS) is a digital copy of assets, an implementation of the digital twin for Industry 4.0. The paper represents a semantic approach for development of AAS, which presents the data model through ontology. The semantic model allows for the presentation of facts, data schemes and meta-data in a unified way, using a global identification scheme. An example from the development of AAS for I4.0 components of an EBMR plant illustrates the approach.
Two-dimensional PIC simulation of the ion-extraction process in an electrostatic field using different electrode configurations
Authors: Singh P , Sridhar G , Maiti N 
Published: February 2023

Abstract
The ion-extraction process from a finite-size photoplasma is simulated by using a two-dimensional electrostatic particle-in-cell code. To investigate the impact of different electrode configurations on the ion extraction process the parallel plate, wire-type, II-type, and M-type electrode configurations are used. The present study compares the ion extraction time of these electrodes and provides a quantitative audit of the photoions. Through this, it is observed that the M-type electrode configuration extracts more ions in less time than the other electrode configurations. Subsequently, this study quantifies the ion collection on different electrodes, which can be further utilized to design the electrode configuration. Moreover, it gives a systematic study of the ion extraction process in an electrostatic field with different electrode configurations.
Growth of mesenchymal stem cells at the surface of silicone, mineral and plant-based oils
Authors: Peng Lihui , Nadal Clémence , Gautrot Julien E 
Published: February 2023

Abstract
Bioemulsions are attractive platforms for the expansion of adherent cells in bioreactors. Their design relies on the self-assembly of protein nanosheets at liquid–liquid interfaces, displaying strong interfacial mechanical properties and promoting integrin-mediated cell adhesion. However, most systems developed to date have focused on fluorinated oils, which are unlikely to be accepted for direct implantation of resulting cell products for regenerative medicine, and protein nanosheets self-assembly at other interfaces has not been investigated. In this report, the composition of aliphatic pro-surfactants palmitoyl chloride and sebacoyl chloride, on the assembly kinetics of poly(L-lysine) at silicone oil interfaces and characterisation of ultimate interfacial shear mechanics and viscoelasticity is presented. The impact of the resulting nanosheets on the adhesion of mesenchymal stem cells (MSCs) is investigated via immunostaining and fluorescence microscopy, demonstrating the engagement of the classic focal adhesion-actin cytoskeleton machinery. The ability of MSCs to proliferate at the corresponding interfaces is quantified. In addition, expansion of MSCs at other non-fluorinated oil interfaces, based on mineral and plant-based oils is investigated. Finally, the proof-of-concept of such non-fluorinated oil systems for the formulation of bioemulsions supporting stem cell adhesion and expansion is demonstrated.
Non-parametric projections of national income distribution consistent with the Shared Socioeconomic Pathways
Authors: Narayan Kanishka B , O’Neill Brian C , Waldhoff Stephanie T , Tebaldi Claudia 
Published: February 2023

Abstract
Understanding and projecting income distributions within countries and regions is important to understanding consumption trends and the distributional consequences of climate impacts and responses. Several global, country-level projections of income distribution are available but most project only the Gini coefficient (a summary statistic of the distribution) or utilize the Gini along with the assumption of a lognormal distribution. We test the lognormal assumption and find that it typically underestimates income in the highest deciles and over-estimates it in others. We find that a new model based on two principal components of national time series data for income distribution provides a better fit to the data for all deciles, especially for the highest and lowest. We also construct a projection model in which the first principal component is driven by the Gini coefficient and the second captures deviations from this relationship. We use the model to project income distribution by decile for all countries for the five shared socioeconomic pathways. We find that inequality is consistently higher than projections based on the Gini and the lognormal functional form, with some countries reaching ratios of the highest to lowest income deciles that are almost three times their value using the lognormal assumption.
Potential adoption of oil palm agroforestry in Sungai Jernih Village, Jambi, Indonesia
Authors: Madjid M I N , Marhaento H , Permadi D B , Susanti A , Budiadi  , Riyanto S , Imron M A , Ardiansyah F , Ridho D , Nissauqodry S V , Susanto M G , Cahyani A P , Irawan B , Yanarita  
Published: February 2023

Abstract
About 3.4 million hectares of oil palm (Elaeis guineensis Jacq.) plantations occupied the forest area in Indonesia by 2019. The enrichment of monoculture oil palm using forest tree species became one of the solutions toward the forest transition processes within a target period associated with the social forestry program. Within this context, smallholder farmers acquired the right to manage oil palm plantations inside forest areas through social forestry permits. Smallholder farmers had to plant and maintain 100 forest tree species per hectare. Research on oil palm agroforestry adoption focused on the factors and barriers to the adoption process and little about the outcome of the adoption. Therefore, this research aimed to predict smallholders’ peak adoption of oil palm agroforestry. Data was collected using Focus Group Discussion (FGD) with 133 members of the forest farmer group in Sungai Jernih Village, Jambi Province. Data were analysed using Adoption and Diffusion Outcome Prediction Tool (ADOPT) to predict peak level adoption and the time to reach peak adoption. Sensitivity analysis was conducted to assess changes in oil palm agroforestry adoption affected by 22 variables. The results showed that peak level adoption and time to reach peak adoption of oil palm agroforestry are 79% and 19 years, respectively. This research suggested that oil palm agroforestry adoption needed external assistance from the government.
Preliminary assessment of arbuscular mycorhizal inoculation in teak and napier grass agroforestry practice treated with soil amendments
Authors: Vijayanathan J , Mohamad A R , Lias M S 
Published: February 2023

Abstract
Soil amendments are known to improve soil structure, increase moisture content, improve fertility and facilitate soil microbial functions. The objective of this study was to determine the effects of gypsum on colonization of arbuscular mycorrhizas in teak plantations planted as fences for napier grass. Teak seedlings were planted in October 2019 and divided into 4 blocks, A, B, C and D comprising 32 seedlings. Plots of A and C were treated with treatments of 3 kg of gypsum and 3 kg of compost (1:1), whereas B and D were control plots. NPK fertilizer was applied at every seedling at the rate of 0.05 kg for all blocks. Seedling heights and mean basal diameter (mm) were assessed at 9 months after planting. Soil samples for microbial study were taken before and after planting at 30 cm depth and screened for mycorrhizal spores and roots at the end of the experiment. Increased values for seedling heights and mean basal diameter (20-35%) were recorded for treatments B and C. Results pointed out that the amount of spore percentages were somewhat reduced in C and D and a slight increase was seen in treatments A and B. Root inoculation percentages in A and C were somewhat higher (1- 6%) as compared to B and D (0.5%). Early findings point out that application of gypsum and composts were not detrimental to the microbial population of arbuscular mycorrhiza as these treatments showed higher presence of hyphae and vesicles in fine roots and did not hamper physical growth. The role of soil amendments needs to be further investigated in terms of enhancing soil microbial population.