bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of the Ronchi test for arbitrary wave aberrations in imaging systems
Authors: Hassani Khosrow 
Published: November 2020

Abstract
The Ronchi test is a simple qualitative method to identify aberrations in imaging systems: a binary grating is superimposed on its own image formed by the system to produce patterns, known as Ronchigrams, that manifest the aberrations in the system. In practice, the experimentally recorded Ronchigrams are compared with model-based simulations to infer the types and amounts of wave aberrations. In this article an effective algorithm to simulate the Ronchigrams in an imaging system under arbitrary third-order wave aberrations is introduced. The method uses simple coordinate interpolation to transfer the grating transmittance from the object to the image space. High-quality Ronchigrams for all types of wave aberrations can easily be produced. For demonstration purposes, experimental Ronchigrams obtained in real imaging systems are also provided and compared with the simulations. The results show that this technique can both be used as an educational tool, and also in a real test setup.
Fourier transform method for the electrostatic self-energy of a solid sphere with uniform volume charge density
Authors: Ciftja Orion 
Published: November 2020

Abstract
The problem of a solid sphere with uniform volume charge density is encountered in virtually all undergraduate calculus-based physics textbooks dealing with the topic of electromagnetism. This example illustrates well the use of Gauss’s law and from there one can easily derive all the quantities of interest such as electrostatic field, potential, self-energy, and so on. Undergraduate physics majors are also well aware of the theory of Fourier transforms from having taken mathematics courses. Nevertheless, despite its great utility, the Fourier transform method is rarely mentioned as a powerful tool to solve physics problems at this level. To address this shortcoming, in this work we propose a possible scenario which may allow an instructor to introduce this powerful method to a proper undergraduate audience without any major pedagogical drawback. The case study that we choose is that of a solid sphere with uniform volume charge density. Specifically, we show the calculation of its electrostatic self-energy by using Fourier transform techniques. The main idea of this work is to draw reader’s attention to the versatility of the approach that can, in principle, be applied to other more geometrically complicated bodies where Gauss’s law does not lead to simple solutions. Concurrently, this work also provides instructional approaches that intertwine content-specific and pedagogical viewpoints that can be useful to all undergraduate students and teachers who wish to enhance their command of the subject.
A neural-network based framework of developing cross interaction in alloy embedded-atom method potentials: application to Zr–Nb alloy
Authors: Lin Bo , Wang Jincheng , Li Junjie , Wang Zhijun 
Published: November 2020

Abstract
Interaction potentials are critical to molecular dynamics simulations on fundamental mechanisms at atomic scales. Combination of well-developed single-element empirical potentials via cross interaction (CI) is an important and effective way to develop alloy embedded-atom method (EAM) potentials. In this work, based on neural-network (NN) models, firstly we proposed a framework to construct CI potential functions via utilizing single-element potentials. The framework contained four steps: (1) extracting characteristic points from single-element potential functions, (2) constructing CI functions by cubic spline interpolation, (3) evaluating the accuracy of CI functions by referring to first-principle (FP) data, and (4) searching for reasonable CI functions via NN models. Then with this framework, we developed a Zr–Nb alloy CI potential utilizing the MA-III (pure Zr potential developed by Mendelev and Ackland in 2007) and the Fellinger, Park and Wilkins (FPW) (pure Nb potential developed by FPW in 2010) potentials as single-element parts. The calculated results with this Zr–Nb alloy potential showed that: (1) the newly developed CI potential functions could simultaneously present the potential-function features of Zr and Nb; (2) the normalized energy–volume curves of L12 Zr3Nb, B2 ZrNb and L12 ZrNb3 calculated by this CI potential reasonably agreed with FP results; (3) the referred MA-III Zr and FPW Nb potentials can satisfactorily reproduce the priority of prismatic slip in Zr and the tension–compression asymmetry of 〈111〉{112} slip in Nb, while other ab initio developed Zr–Nb alloy potentials cannot. Our study indicates that, this NN based framework can take full advantage of single-element potentials, and is very convenient to develop EAM potentials of alloys; moreover, the new-developed Zr–Nb alloy EAM potential can reasonably describe the complicated deformation behaviors in Zr–Nb systems.
Molecular beam magnetic resonance coupled with a cryogenically cooled, pulsed laser vaporization source and time-of-flight mass spectrometry
Authors: Fuchs Thomas M , Schäfer Rolf 
Published: November 2020

Abstract
A molecular beam magnetic resonance apparatus designed for the study of polyatomic molecules and small metal clusters is described. In contrast to atoms, vibrational and rotational excitation in clusters and molecules invoke spin relaxation upon a change of magnetic flux density. To prevent this, a pulsed laser vaporization source with a cryogenically cooled nozzle is utilized to minimize thermal excitation and a magnet setup has been designed to diminish magnetic field fluctuations. The apparatus is evaluated by Stern–Gerlach and resonance experiments on an atomic europium beam with the identical pulsed laser vaporization source.
Resonance-based bandwidth Fourier decomposition method for gearbox fault diagnosis
Authors: Deng Minqiang , Deng Aidong , Zhu Jing , Shi Yaowei , Liu Yang , Chen Qiang 
Published: November 2020

Abstract
This paper aims to investigate the response mechanism of faulty gears, and further proposes a resonance-based bandwidth Fourier decomposition (RBBFD) method for gearbox fault identification. To reveal the vibration patterns of the gear-pair system, a dynamic model with time-varying stiffness is established to obtain the transient response excited by local damage. The analysis results demonstrate that the impulse response of a faulty gear is essentially carried by the natural frequency instead of the widely recognized meshing frequency and its harmonies. After that, the RBBFD method is developed based on the dynamic characteristics. In the proposed method, the resonance frequencies of the gear system are estimated according to the maximum point distribution of the Fourier spectrum, and then the Fourier spectrum bandwidth optimization algorithm is introduced to decompose the vibration signal into mono-components centered on the estimated natural frequencies. A new criterion termed the characteristic frequency ratio is utilized to measure the fault-related degree of the decomposed modes, and the fault type is identified by Hilbert demodulation. The effectiveness of RBBFD is verified through two diagnostic cases. The comparison with several state-of-art works validates the superiority of the proposed method in gearbox fault diagnosis.
A particle debonding model considering interface nanoscale damage effect
Authors: Liu Yu , Chen Jieshi , Dong Xianghuai 
Published: November 2020

Abstract
The debonding of the inclusions or second phase particles from matrix which is controlled by energy and stress condition is an important source of voids nucleation in engineering materials. In this paper, firstly it is confirmed that energy condition for debonding can easily be satisfied for micron scale particles in plastic deformation by numerical simulation; then a stress controlled debonding model introducing the effect of nanoscale damage of the interface is proposed; then the parameters of the model are determined by fitting the published experimental data. Unlike traditional debonding models, the proposed model can reasonably predict the size effect that the debonding strain will increase with the decrease of particle size at micron scale, which was observed by experiments.
Evaluation of eddy current distortion and field inhomogeneity distortion corrections in MR diffusion imaging using log-demons DIR method
Authors: Arsenault Theodore , Yin Fang Fang , Chino Junzo , Craciunescu Oana , Chang Jim Zheng 
Published: November 2020

Abstract
To investigate the feasibility of the log-demons deformable image registration (DIR) method to correct eddy current and field inhomogeneity distortions while preserving diffusion tensor information. Diffusion-weighted images (DWIs) are susceptible to distortions caused by eddy current and echo-planar imaging (EPI) gradients. We propose a post-acquisition correction algorithm using the log-demons DIR technique for eddy current and field inhomogeneity distortions of DWI. The new correction technique was applied to DWI acquired using a diffusion phantom and the multiple acquisitions for standardization of structural imaging validation and evaluation (MASSIVE) brain database. This method is compared to previous methods using cross-correlation, mutual information (MI). In the phantom study, the log-demons algorithm reduced eddy current and field inhomogeneity distortions while preserving diffusion tensor information when compared to affine and demon’s registration techniques. Analysis of the tensor metrics using percent difference and the root mean square of the apparent diffusion coefficient and fractional anisotropy found that the log-demons algorithm outperforms the other algorithms in terms of preserving diffusion information. In the MASSIVE study, the average MI of all slices increased for both eddy current and field inhomogeneity distortion correction. The average absolute differences of all slices between corrected images with opposing gradients were also on average decreased. This work indicates that the log-demons DIR algorithm is feasible to reduce eddy current and field inhomogeneity distortions while preserving quantitative diffusion information.
Quantitative analysis of bony birth canal for periacetabular osteotomy patient by template fitting
Authors: Shao Long , Li Heng , Liu Xinxin , Wang Yanjun , Shi Liujia , Ai Danni , Fan Jingfan , Song Hong , Zhang Hong , Yang Jian 
Published: November 2020

Abstract
Periacetabular osteotomy (PAO) is a joint preservation procedure for developmental dysplasia of the hip. Such a procedure requires osteotomy of the medial wall of the acetabulum, which may cause the narrow of the bony birth canal and increase the risk of complications during the childbirth process in the future. Using quantitative analysis of the bony birth canal to determine the risk of complications for the childbirth process remains a challenging task. The purpose of this paper is to explore a new 3D CT measurement method to quantify the narrowest parameters of the bony birth canal of the female patients with hip dysplasia before and after unilateral PAO surgery. By analyzing the impact of PAO surgery on the bony birth canal, the patient’s risk of complications during the childbirth process in the future can be estimated, and it can be utilized for doctors to determine the impact of unilateral PAO for choosing appropriate delivery method. In this paper, a mean shape of the preoperative pelvises is obtained by using the statistical shape model algorithm, and the mean shape includes pelvic shape features of all the preoperative pelvises, and it can be utilized as the standard pelvic template. A bidirectional iterative algorithm is used to generate a standard bony birth canal path template. Then, the pelvic registration and principal plane deformation constraint are utilized to calculate the optimal bony birth canal path. The proposed method is verified in 31 cases of CT data with the approval of the institutional review board. The test data contain preoperative and postoperative CT images. Compared with the benchmark method, the measurement accuracy of the narrowest position and diameter of the bony birth canal is improved by 65% and 78%, respectively. In addition, the processing speed is increased by 32%. Experimental results demonstrate that the proposed method has high accuracy and validity for quantifying the bony birth canal. The proposed method can measure the anatomical parameters of the bony birth canal accurately. In addition, the doctor can make optimal planning for childbirth with the help of the quantitative analysis of the bony birth canal.
A scan driver including light emission control integrated by metal-oxide thin-film transistors
Authors: Liu Chun , Lin Yi-Zhen , Wu Wei-Jing , Zhou Lei , Xu Miao , Wang Lei , Peng Jun-Biao 
Published: November 2020

Abstract
This paper presents a new scan driver including a light emission control module, which is fabricated by metal oxide thin-film transistors (TFTs) with back channel etched structures. The proposed scan driver employs the capacitor coupling effect and two-step-resetting method to output SCAN and EM signals simultaneously. Therefore, there is no need to design the scan driver circuit and the light emission control circuit separately, which saves the resources of peripheral driving signals and area of TFT integrated circuits. Thirty stages of the proposed scan driver are fabricated on a glass substrate to verify its function. Experimental results show that each stage can output full-swing waveforms for SCAN and EM signals, which have little distortion and exhibit good stability with a 10 us pulse width. The measured power consumption per stage of the proposed scan driver is 85 µW at a clock frequency of 33.4 kHz.
Electronic Maxwell’s equations
Authors: Li Mingjie , Shi Peng , Du Luping , Yuan Xiaocong 
Published: November 2020

Abstract
To date, the wave nature of electron has been widely researched, together with its similarity to optics. To unify electronic waves and electromagnetic waves, we establish four equations analogous to Maxwell’s equations by expressing the Dirac equation in terms of the quaternions. We develop some fundamental theories from the electronic version of Maxwell’s equations. In practice, solving electron wave problem is convenient without appearance of quantum operators such as Pauli matrices. The benefit is its potential in the analysis and applications of diverse electron beams, for example, phase-shift control. Moreover, physical quantities represented by electronic vector fields are notably similar to those in optics, making it possible to apply some ideas developed in optics in the research of electron.
Symmetry-protection of multiphoton states of light
Authors: Lasa-Alonso Jon , Molezuelas-Ferreras Martín , Miguel Varga J J , García-Etxarri Aitzol , Giedke Géza , Molina-Terriza Gabriel 
Published: November 2020

Abstract
In this manuscript we analyze the emergence of protected multiphoton states in scattering problems with cylindrical symmetry. In order to do that, we first provide a formal definition of the concept of postselected symmetry-protection. We show that the notion of symmetry-protection is not limited to one- or two-photon states, on the contrary, it can be formally extended to the multiphoton case. In addition, we prove for the case of cylindrical symmetry that all possible multiphoton protected states are constructed from a small set of one- and two-photon states. Finally, we point out possible applications that symmetry-protected states may have in quantum communications, concretely, in the construction of decoherence-free subspaces.
Interacting quantum mixtures for precision atom interferometry
Authors: Corgier Robin , Loriani Sina , Ahlers Holger , Posso-Trujillo Katerine , Schubert Christian , Rasel Ernst M , Charron Eric , Gaaloul Naceur 
Published: November 2020

Abstract
We present a source engineering concept for a binary quantum mixture suitable as input for differential, precision atom interferometry with drift times of several seconds. To solve the non-linear dynamics of the mixture, we develop a set of scaling approach equations and verify their validity contrasting it to the one of a system of coupled Gross–Pitaevskii equations. This scaling approach is a generalization of the standard approach commonly used for single species. Its validity range is discussed with respect to intra- and inter-species interaction regimes. We propose a multi-stage, non-linear atomic lens sequence to simultaneously create dual ensembles with ultra-slow kinetic expansion energies, below 15 pK. Our scheme has the advantage of mitigating wave front aberrations, a leading systematic effect in precision atom interferometry.
Super sub-wavelength interference via high-order correlation of light fields
Authors: Zhang Erfeng , Xu Yaokun , Li Dun , Dai Weihua 
Published: November 2020

Abstract
We propose a scheme to realize super sub-wavelength interference in virtue of high-order spatial correlation with a programmable light source, which can be applied to enhance precision in measurement and control. In this proposal, the light source is produced by modulating the wavefront of a laser beam randomly in time with a phase-only spatial light modulator (SLM). Combing the intensity patterns measured by a CCD camera and the computed intensity patterns using the phase masks loaded on the SLM, the super sub-wavelength interference pattern of an object can be obtained by using high-order spatial correlation measurement. The resolution of the interference pattern can, in principle, be arbitrarily high, and a higher resolution can be obtained as the order of the correlation function increases.
Photoionization dynamics of Mg atoms during Paul trap loading using a two-color UV laser system
Authors: Aksenov Mikhail , Zalivako Ilia , Semenin Nikita , Smirnov Vasilii , Zhuravlev Igor , Vishnyakov Pavel , Sidorov Pavel , Borisenko Alexander , Semerikov Ilia , Khabarova Ksenia , Kolachevsky Nikolai 
Published: November 2020

Abstract
Trapped ions have proven to be a powerful instrument in quantum logic, precision metrology and tests of fundamental theories. Many applications require isotopically pure ion crystals to be trapped; however, selective loading methods require either isotopically pure atom sources or dedicated ultraviolet laser systems. Here we investigate the loading dynamics of the isotopically pure magnesium ion crystals photoionized and Doppler-cooled with a two-color UV laser system at 285 nm and 280 nm. The system shares the same tapered amplifier and the first stage of a second-harmonic generation for both wavelengths, which significantly reduces the complexity and cost of the experiment. A selective loading rate of 0.05 ions s−1 was achieved, supporting theoretical evaluations.
Using modern CAE systems for assessing the building structures made of traditional building materials technical condition
Authors: Alpatov V , Balzannikov M 
Published: November 2020

Abstract
Modern “computer-aided design” (CAD) systems allow to process difficult researches on building structures of buildings and constructions. Program complexes, allowing to calculate and get performance predictions of materials and constructions made from them, considered as CAE (Computer Aided Engineering). CAE systems are used not only for creating and researching new materials, but also widely used for rating of traditional material condition. For brick chimney technical condition research program complexes SolidWorks and «Lira-W» were used. Using these calculation complexes structural rigidity, brickwork structures strength ratings were made, the need for taking measures to strengthen the construction was set. Using numerical researches, hazardous locations were identified along the height of the structure. For hazardous locations, a comparative analysis of obtained values of stresses in masonry was carried out in two calculation complexes.
Study of bonding zone composite reinforced structures
Authors: Nikitin K E , Zhukov D I , Moskovtseva V S 
Published: November 2020

Abstract
A bonding zone between elements of layered composite concrete structure was investigated. Results of stress-strain state, nonlinear deformation, and crack resistance of this zone are presented. The bonding zone simulation was performed using the developed methodology based on the finite element method. The problem was solved in a nonlinear formulation using elements with nonlinear material properties and one-side contact elements. A fragment of a layered structure made of two concretes with different strength and under the action of shear forces was considered. Based on the available experimental data, shear stiffness of the bonding zone was calculated. The simulation of the deformation process for the composite structure was performed taking into account its nonlinear deformation and consideration of the cracking process up to the moment of its complete failure. The obtained results of are compared with experimental data. The necessity of using the actual strength and deformation characteristics of the shear of the bonding zone when modeling the deformation process and evaluating the ultimate breaking load is shown.
Differences in the calculation of reinforcement in reinforced concrete floor slabs, calculated in the LIRA program according to the theories of Wood R H and Karpenko N I
Authors: Khayrnasov K Z 
Published: November 2020

Abstract
The calculation methodology presented in the program LIRA is based on the theory of academician N I Karpenko about reinforced concrete structures and their deformations. As an additional option for calculating and constructing elements in the program, the method of Wood’s theory. At the same time, the results of reinforcement calculated according to these theories are significantly different, while the use of any of these theories is allowed by normative documents binding on the territory of Russia and the final choice of theory depends only on the experience of the engineer. The aim of this work is to identify the features of calculating the distribution of reinforcement according to the theories of Wood’s and Karpenko’s. The results of the study of reinforced concrete floor slabs loaded with a constant uniformly distributed load with articulated support on short sides are obtained. The study showed that reinforcement according to the theories of Karpenko’s and Wood’s differs mainly by 10 and in environs of consolidation by 70%. The results were analyzed.
Research of features of increasing operational reliability of historical buildings in Russia
Authors: Krygina A M , Koshlich Y A , Oberemok M I 
Published: November 2020

Abstract
Considering the high importance of historic buildings in shaping the architectural appearance of Russian cities, the features of reconstruction of these buildings and structures are performed in this paper to ensure the operational safety of the properties and their structural safety. There is proposed a comprehensive approach to solving the problem which includes the following main types of research: studying the design features of historical real estate, analyzing the reliability of structural and finishing materials, including the study of their authenticity. Special attention is paid to assessing the impact of natural and technogenic impacts on the reliability of the structural scheme of the object as a whole and its individual elements, monitoring new construction in adjacent territories, geotechnical monitoring, assessing the impact of building reconstruction on changes in the design scheme of the building.