bluuebunny/crossref_metadata_2025_split huggingface dataset:
The realization of quantum anomalous Hall effect in two dimensional electron gas
Authors: Wu Hua-rui , Wu Bing-lan , Cheng Shu-guang , Jiang Hua 
Published: November 2020

Abstract
The quantum anomalous Hall effect (QAHE), carrying dissipationless chiral edge states, occurs without any magnetic field. Two main strategies were proposed to host QAHE: the magnetic topological insulator thin films and graphene systems. Only the former one was realized in experiment at low temperature. In this paper, by dealing with the two-dimensional electron gas with an anti-dot lattice, a realistic platform is proposed to host the QAHE with both Chern number

C
=
−
1

and

C
=
2

. Based on the calculation of the Berry curvature integral and spacial wave function, the topological nature of the QAH edge states is well demonstrated. In the QAH region, the conductance shows quantized plateaus and their values are robust against Anderson disorder. In addition, we have also studied the effects of the size and shape of the anti-dot lattice on QAHE and they provide extra manners to adjust the system parameters. Taking the advantages of the well developed micro-manufacture technique in semiconductors, the proposal is experimentally accessible in micro-scale.
Effect of zitterbewegung on the propagation of wave packets in ABC-stacked multilayer graphene: an analytical and computational approach
Authors: Lavor I R , da Costa D R , Chaves Andrey , Sena S H R , Farias G A , Van Duppen B , Peeters F M 
Published: November 2020

Abstract
The time evolution of a low-energy two-dimensional Gaussian wave packet in ABC-stacked n-layer graphene (ABC-NLG) is investigated. Expectation values of the position (x, y) of center-of-mass and the total probability densities of the wave packet are calculated analytically using the Green’s function method. These results are confirmed using an alternative numerical method based on the split-operator technique within the Dirac approach for ABC-NLG, which additionally allows to include external fields and potentials. The main features of the zitterbewegung (trembling motion) of wave packets in graphene are demonstrated and are found to depend not only on the wave packet width and initial pseudospin polarization, but also on the number of layers. Moreover, the analytical and numerical methods proposed here allow to investigate wave packet dynamics in graphene systems with an arbitrary number of layers and arbitrary potential landscapes.
Robust cepstral analysis at variable wavelength scan depth for narrowband tunable laser absorption spectroscopy
Authors: Li Jidong , Schwarm Kevin K , Wei Chuyu , Mitchell Spearrin R 
Published: November 2020

Abstract
This work focuses on optimizing the modified free induction decay (m-FID) method, or cepstral analysis, for accuracy, precision, and robustness in performing laser absorption spectroscopy at conditions of variable baseline distortion where laser tuning range is of a similar order of magnitude as the targeted spectral linewidth. The optimum selections of the initial and final time of the m-FID signal were assessed at variable scan indices (ratio of laser scan range to spectral linewidth), and guidance is offered in parameter selection based on scan index and noise characteristics of the optical system. The sensitivities of the m-FID method to multiple types of baseline distortion were also analyzed to reflect typical experimental factors such as beam attenuation, background radiation, and laser stability. Experimental demonstration of the technique was performed with an interband cascade laser targeting the CO2 transition (0001

←

0000) R(60) near 4.2 micron to measure gas concentration at variable scan indices in a static cell by using both the m-FID and direct absorption spectroscopy (DAS) method while varying injection current amplitude. An estimated baseline was determined by the measured laser output and superimposed with different types and levels of distortion. Under conditions of signal distortion, the m-FID method is shown to demonstrate superior accuracy and precision with smaller deviations in time than that rendered by typical DAS, especially at smaller scan depths, showing its potential for measurements at elevated pressures or at a high scan frequency where distributed feedback lasers typically yield narrower tuning range.
Fixing positions and orientations of laser trackers during bundle adjustment in multi-station measurements
Authors: Wang Zhaoyi , Luo Tao , Wang Wei , Huang Qingqing , Li Xiao 
Published: November 2020

Abstract
The accumulated errors in multi-station measurements make it challenging to meet higher precision requirements for annular or straight tunnel measurements in the accelerator alignment field. In this paper, a study on fixing positions and orientations of laser trackers during the bundle adjustment is presented. First, we adopt the mixed least squares-total least squares algorithm to calculate the spatial-transformation parameters. Then, according to the principle of bundle adjustment based on laser trackers, we design four schemes and compare them to determine which scheme results in the highest precision. Experimental results show that fixing each station’s position and orientation can considerably decrease the absolute point errors from 0.130 to 0.069 mm within 15 m × 10 m × 3 m, and fixing stations’ orientations is better than fixing their positions. This research can derive high-precision schemes that effectively reduce accumulated errors in annular or straight tunnel measurements, and it can apply to other robotic sensors as well.
The effects of substitutional Fe-doping on magnetism in MoS2 and WS2 monolayers
Authors: Kang Kyungnam , Fu Shichen , Shayan Kamran , Anthony Yoshimura , Dadras Siamak , Yuzan Xiong , Kazunori Fujisawa , Terrones Mauricio , Zhang Wei , Strauf Stefan , Meunier Vincent , Vamivakas A Nick , Yang Eui-Hyeok 
Published: November 2020

Abstract
Doping of two-dimensional (2D) semiconductors has been intensively studied toward modulating their electrical, optical, and magnetic properties. While ferromagnetic 2D semiconductors hold promise for future spintronics and valleytronics, the origin of ferromagnetism in 2D materials remains unclear. Here, we show that substitutional Fe-doping of MoS2 and WS2 monolayers induce different magnetic properties. The Fe-doped monolayers are directly synthesized via chemical vapor deposition. In both cases, Fe substitutional doping is successfully achieved, as confirmed using scanning transmission electron microscopy. While both Fe:MoS2 and Fe:WS2 show PL quenching and n-type doping, Fe dopants in WS2 monolayers are found to assume deep-level trap states, in contrast to the case of Fe:MoS2, where the states are found to be shallow. Using μm- and mm-precision local NV− magnetometry and superconducting quantum interference device, we discover that, unlike MoS2 monolayers, WS2 monolayers do not show a magnetic phase transition to ferromagnetism upon Fe-doping. The absence of ferromagnetism in Fe:WS2 is corroborated using density functional theory calculations.
Gold nanoparticle-assisted plasmonic enhancement for DNA detection on a graphene-based portable surface plasmon resonance sensor
Authors: Prabowo Briliant Adhi , Purwidyantri Agnes , Liu Bei , Lai Hsin-Chih , Liu Kou-Chen 
Published: November 2020

Abstract
The impact of different gold nanoparticle (GNP) structures on plasmonic enhancement for DNA detection is investigated on a few-layer graphene (FLG) surface plasmon resonance (SPR) sensor. Two distinct structures of gold nano-urchins (GNu) and gold nanorods (GNr) were used to bind the uniquely designed single-stranded probe DNA (ssDNA) of Mycobacterium tuberculosis complex DNA. The two types of GNP-ssDNA mixture were adsorbed onto the FLG-coated SPR sensor through the π-π stacking force between the ssDNA and the graphene layer. In the presence of complementary single-stranded DNA, the hybridization process took place and gradually removed the probes from the graphene surface. From SPR sensor preparation, the annealing process of the Au layer of the SPR sensor effectively enhanced the FLG coverage leading to a higher load of the probe DNA onto the sensing interface. The FLG was shown to be effective in providing a larger surface area for biomolecular capture due to its roughness. Carried out in the DNA hybridization study with the SPR sensor, GNu, with its rough and spiky structures, significantly reinforced the overall DNA hybridization signal compared with GNr with smooth superficies, especially in capturing the probe DNA. The DNA hybridization detection assisted by GNu reached the femtomolar range limit of detection. An optical simulation validated the extreme plasmonic field enhancement at the tip of the GNu spicules. The overall integrated approach of the graphene-based SPR sensor and GNu-assisted DNA detection provided the proof-of-concept for the possibility of tuberculosis disease screening using a low-cost and portable system to be potentially applied in remote or third-world countries.
Nanoconstructs as a versatile tool for detection and diagnosis of Alzheimer biomarkers
Authors: Gopalan Divya , Pandey Abhijeet , Alex Angel Treasa , Kalthur Guruprasad , Pandey Sureshwar , Udupa Nayanabhirama , Mutalik Srinivas 
Published: November 2020

Abstract
The current review focuses towards the advancements made in the past decade in the field of nanotechnology for the early Alzheimer’s disease (AD) diagnosis. This review includes the application of nanomaterials and nanosensors for the early detection of the main AD biomarkers (amyloid beta, phosphorylated tau, apolipoprotein E4 allele or APOE4, microRNAs, cholesterol, hydrogen peroxide etc) in biological fluids, to detect the biomarkers at a very low concentration ranging in pico, femto and even atto molar concentrations. The field of drug development has always aimed and is constantly working on developing disease modifying drugs, but these drugs will only succeed when given in the early disease stages. Thus, developing efficient diagnostic tools is of vital importance. Various nanomaterials such as liposomes; dendrimers; polymeric nanoparticles; coordination polymers; inorganic nanoparticles such as silica, manganese oxide, zinc oxide, iron oxide, super paramagnetic iron oxides; quantum dots, silver nanoparticles, gold nanoparticles, and carbon based nanostructures (carbon nanotubes, graphene oxide, nanofibres, nanodiamonds, carbon dots); Up-conversion nanoparticles; 2D nanomaterials; and radioactive nanoprobes have been used in constructing and improving efficiency of nano-sensors for AD biosensing at an early stage of diagnosis.
Balls rolling down a playground slide: What factors influence their motion?
Authors: Pendrill Ann-Marie 
Published: November 2020

Abstract
Take a selection of balls and marbles along to a nearby playground slide and let students investigate factors that may influence how balls accelerate down an inclined plane. Students can make hypotheses in small groups, plan investigations to test multiple possible explanations and draw conclusions about the importance of different variables. The experiments illustrate the principle of equivalence between inertial and gravitational mass, as well as of the importance of mass distribution. Students can develop an intuitive feeling for these concepts even without dealing with the full mathematical treatment, which involves torque, angular momentum and moment of inertia, typically treated in high-school or introductory university physics courses. The paper discusses this investigation as part of a setup of teacher professional development events on a playground.
Liver-ultrasound-guided lung tumour tracking for scanned proton therapy: a feasibility study
Authors: Krieger Miriam , Giger Alina , Jud Christoph , Duetschler Alisha , Salomir Rares , Bieri Oliver , Bauman Grzegorz , Nguyen Damien , Cattin Philippe C , Weber Damien C , Lomax Antony J , Zhang Ye 
Published: November 2020

Abstract
Pencil beam scanned (PBS) proton therapy of lung tumours is hampered by respiratory motion and the motion-induced density changes along the beam path. In this simulation study, we aim to investigate the effectiveness of proton beam tracking for lung tumours both under ideal conditions and in conjunction with a respiratory motion model guided by real-time ultrasound imaging of the liver. Multiple-breathing-cycle 4DMRIs of the thorax and abdominal 2D ultrasound images were acquired simultaneously for five volunteers. Deformation vector fields extracted from the 4DMRI, referred to as ground truth motion, were used to generate 4DCT(MRI) data sets of two lung cancer patients, resulting in 10 data sets with variable motion patterns. Given the 4DCT(MRI) and the corresponding ultrasound images as surrogate data, a patient-specific motion model was built. The model consists of an autoregressive model and Gaussian process regression for the temporal and spatial prediction, respectively. Two-field PBS plans were optimised on the reference CTs, and 4D dose calculations (4DDC) were used to simulate dose delivery for (a) unmitigated motion, (b) ideal 2D and 3D tracking (both beam adaption and 4DDC based on ground truth motion), and (c) realistic 2D and 3D tracking (beam adaption based on motion predictions, 4DDC on ground truth motion). Model-guided tracking retrieved clinically acceptable target dose homogeneity, as seen in a substantial reduction of the D5%–D95% compared to the non-mitigated simulation. Tracking in 2D and 3D resulted in a similar improvement of the dose homogeneity, as did ideal and realistic tracking simulations. In some cases, however, the tracked deliveries resulted in a shift towards higher or lower dose levels, leading to unacceptable target over- or under-coverage. The presented motion modelling framework was shown to be an accurate motion prediction tool for the use in proton beam tracking. Tracking alone, however, may not always effectively mitigate motion effects, making it necessary to combine it with other techniques such as rescanning.
Towards effective assessment of normal hearing function from ABR using a time-variant sweep-tone stimulus approach
Authors: Jiang Yanbing , Samuel Oluwarotimi Williams , Zhang Haoshi , Chen Shixiong , Li Guanglin 
Published: November 2020

Abstract

Objective. The auditory brainstem response (ABR) audiometry is a means of assessing the functional status of the auditory neural pathway in the clinic. The conventional click ABR test lacks good neural synchrony and it mainly evaluates high-frequency hearing while the common tone-burst ABR test only detects hearing loss of a certain frequency at a time. Additionally, the existing chirp stimuli are designed based on average data of cochlear characteristics, ignoring individual differences amongst subjects. Approach. Therefore, this study designed a new stimulus approach based on a sweep-tone concept with a time variant and spectrum characteristics that could be customized based on an individual’s cochlear characteristics. To validate the efficiency of the proposed method, we compared its performance with the click and tone-bursts using ABR recordings from 11 normal-hearing adults. Main results. Experimental results showed that the proposed sweep-tone ABR achieved a higher amplitude compared with those elicited by the click and tone-bursts. When the stimulus level or rate was varied, the sweep-tone ABR consistently elicited a larger response than the corresponding click ABR. Moreover, the sweep-tone ABR appeared earlier than the click ABR under the same conditions. Specifically, the mean wave V peak-to-peak amplitude of the sweep-tone ABR was 1.3 times that of the click ABR at 70 dB nHL (normal hearing level) and a rate of 20 s−1, in which the former saved 40% of test time. Significance. In summary, the proposed sweep-tone approach is found to be more efficient than the traditional click and tone-burst in eliciting ABR.
Machining method for controlling the behaviours of Bingham fluids in cluster magnetorheological polishing pads
Authors: Luo Bin , Yan Qiusheng , Huang Zhanliang , Pan Jisheng , Fu Youzhi 
Published: November 2020

Abstract
Cluster magnetorheological finishing is a novel machining method for attaining super-smooth and even surfaces. The aim of the research is to strengthen the role of cluster magnetorheological polishing pads and improve the material removal rate (MRR) while attaining smooth and undamaged surfaces. To this end, a novel polishing disk with three-dimensional (3D) microstructures was formed by machining an array of holes on the surface of a polishing disk. The influences of the type of abrasives, geometric parameters of the holes, and polishing time on the roughness and MRR of the machined surface were explored. The test result showed that a polishing disk with multiple holes contributes to a higher MRR and a lower surface roughness relative to a smooth polishing disk, significantly improving the polishing effect; the diameter and distribution of multiple holes on the surface of the polishing disk exhibit a significant effect on the polishing process. The polishing effect with silica sols is most remarkably improved. The solid-state chemical reaction between sapphire and silica sols promotes material removal; relative to a smooth polishing disk, the MRR is increased by 107% and the surface roughness is decreased by 11%. The surface roughness is reduced from Ra 5.14 nm to Ra 0.24 nm by utilising the optimised technological parameters. Under the synergistic action of mechanical removal enhancement of polishing disks with multiple holes and chemical removal of silica sol sapphire can obtain super smooth undamaged surfaces efficiently.
Quantum hydrodynamics description of spin-1 Bose–Einstein condensates
Authors: Trukhanova Mariya Iv , Obukhov Yuri N 
Published: November 2020

Abstract
We develop a novel model of the magnetized spin-1 Bose–Einstein condensate (BEC) of neutral atoms, using the method of many-particle quantum hydrodynamic (QHD) and propose an original derivation of the system of continual equations. We consider bosons with a spin-spin interaction and a short range interaction in the first order in the interaction radius, on the of basis of the self-consistent field approximation of the QHD equations. We demonstrate that the dynamics of the fluid velocity and magnetization is determined by a nontrivial modification of the Euler and Landau–Lifshitz equation, and show that a nontrivial modification of the spin density evolution equation contains the spin torque effect that arises from the self-interactions between spins of the bosons. The properties of the dispersion spectrum of collective excitations are described. We obtain the new contribution of the self-interaction of spins in the spin wave spectrum together with the influence of an external magnetic field and spin-spin interactions between polarized particles. The anisotropic spin wave instability is predicted.
Editorial Preface
Authors: Jan Pahl Peter , Galishnikova Vera , Vatin Nikolai , Kharun Makhmud , Koroteev Dmitry 
Published: November 2020

The present proceedings include a selection of papers submitted to the International Conference on Engineering Systems 2020 (ICES 2020), which was held during 14-16 October 2020 in the RUDN University, Moscow, Russia.
ICES 2020 was dedicated to the 60th anniversary of RUDN University. International Conference on Engineering Systems (ICES), held annually at the Peoples’ Friendship University of Russia (RUDN University), has created a platform for summarizing research in various areas of engineering. The aim of the conference is to foster and conduct collaborative interdisciplinary research amongst the researchers, professionals and industrialists to share their research experiences and indulge in interactive discussions and special sessions at the event.
In light of travel restrictions around the world to control COVID-19 pademic, ICES 2020 adopted the format of virtual conference through Google Meet network to provide a forum for experts and scholars to share real-time information and discuss the latest findings on various engineering fields. The conference included keynote speech and online discussion, and each presenter has 20–25 minutes (including Q&A).
With the full support from the International Scientific Committee, all submissions have been through rigorous review and process to meet the requirements of international publication standard. Accepted papers were presented in five sessions of the conference: 1) Fundamental Engineering, 2) Civil and Structural Engineering, 3) Mechanical Engineering, 4) Composite Materials, 5) Hydraulic and Geological Engineering. We hope that this collection will be useful for many specialists and researchers from various engineering fields.
List of Conference Chair, Conference secretary, International Scientific Committee and Guest Editors are available in this pdf.
Systems thinking ontology of emergent properties for complex engineering systems
Authors: Nikolaev M Y , Fortin C 
Published: November 2020

Abstract
This paper presents a developed ontology of emergent properties characterizing the emergent behavior of complex engineering systems, which is the emergence of greater functionality of the overall system compared to the sum of the functionalities of system components. The ontology is based on the systems thinking approach used in systems architecture, one of the key points to consider in the conceptual design of engineering systems and used to manage the complexity of systems. Firstly, in the paper, research attributes and the adaptation of the term “ontology” for systems thinking are given. Secondly, the coverage of analyzed literature sources in the description of the literature search is demonstrated. Thirdly, the developed ontology consisting of semantics and relationships of systems emergent properties is presented. The proposed ontology is followed by highlighting its possible systems engineering applications. Finally, in conclusion, the benefits of the developed ontology are mentioned. Overall, the current paper combines aspects of systems engineering with key elements of the design of complex systems.
Features of the stress-strain state in the corner zones of structures
Authors: Frishter L 
Published: November 2020

Abstract
Corner regions of structures are characterized by a complex stress-strain state (SSS), caused by both the shape of the boundary or the “geometric factor”, and the finite rupture of the specified forced deformations, mechanical properties that go to the contact surface of the elements of composite structures. The relevance of the work consists in the analysis of local SSS in the corner zone of the region boundary with various study approaches: theoretical, experimental. For the theoretical analysis of the SSS of the region, we consider the resolving system of equations of the problem of the theory of elasticity in the zone of the cutout of the boundary and elements of the similarity theory; the photoelasticity method is used for experimental studies. An experimental solution was obtained on polymer composite models with an angle cut of the boundary under the action of forced deformations in one of the regions. The analysis of possibilities of theoretical, experimental approaches of SSS studies in zones with irregular point of border allows to reveal zones of applicability of solutions of linear elasticity problem.