bluuebunny/crossref_metadata_2025_split huggingface dataset:
Opto-electronic properties of poly-crystalline La doped BaSnO3 films deposited on quartz substrates
Authors: Kumar Akash , Maurya Sandeep , Patwardhan Suren , Balasubramaniam K R 
Published: February 2021

Abstract
Highly conducting and transparent thin films of La
x
Ba1 − x
SnO3 (x = 0, 0.01 and 0.05) were grown on quartz substrates via pulsed laser deposition. Conductivity increases in orders of magnitude upon vacuum annealing of the as–deposited films. This is attributed to the significant enhancement in carrier concentration due to the increased oxygen vacancy defects (V

O

∙
∙

). Enhanced carrier concentration improves the metallicity in the films at room temperature. Metal to semiconductor transition (MST) is observed in the films with n
e

⩾

1019 cm−3 at low temperatures. The MST shifts towards absolute zero temperature as the carrier concentration in the film increases. Low–temperature resistivity analysis suggests that the charge transport is mainly governed by strong electron–electron interaction. UV–Vis spectroscopy confirms a 60%–80% transmittance in the visible range (400–800 nm) for all the films. Due to the large change in carrier concentration, Burstein Moss (BM) shift is observed, and the bandgap ranges between 3.65–3.98 eV. The effective mass of electron and refractive index estimated from the BM shift and transmittance are found to be 0.6 m
e
and 2, respectively.
Prediction of half-lives of even–even superheavy nuclei
Authors: Pathak Deepika , Singh Navdeep , Kaur Harjeet , Jain Sudhir R 
Published: February 2021

Abstract

α-decay half-lives (

T

1
/
2

α

-values) of even–even and superheavy nuclei (SHN) are determined employing interaction potential involving Coulomb and proximity potentials. The obtained results are compared with the experimental ones and to assess the precision of the present model in reproducing the experimental half-lives, a comparison is drawn with the other methods as well. We require disintegration energy (Q

α
-values) as an input in order to predict the (

T

1
/
2

α

-values) of an experimentally unknown SHN. So, utilizing periodic-orbit theory within microscopic-macroscopic formalism, we have calculated the binding energies and thereafter, Q

α
-values of known SHN. The results are found to be in good agreement with the experimental ones. Subsequently, we predict the logarithmic values of

T

1
/
2

α

’s for even–even unknown SHN whose atomic numbers lie in 118 ⩽ Z ⩽ 126 regime and compare our results with those calculated employing other theoretical methods. Also, the study of spontaneous fission half-lives and branching ratios leads us to predict the SHN which can be identified through α-decay chains in the laboratories. We believe that this work can play a significant role in the experiments leading to the synthesis and identification of new superheavy elements.
Current-induced forces in single-resonance systems
Authors: Deghi Sebastián E , Fernández-Alcázar Lucas J , Pastawski Horacio M , Bustos-Marún Raúl A 
Published: February 2021

Abstract
In recent years, there has been an increasing interest in nanoelectromechanical devices, current-driven quantum machines, and the mechanical effects of electric currents on nanoscale conductors. Here, we carry out a thorough study of the current-induced forces and the electronic friction of systems whose electronic effective Hamiltonian can be described by an archetypal model, a single energy level coupled to two reservoirs. Our results can help better understand the general conditions that maximize the performance of different devices modeled as a quantum dot coupled to two electronic reservoirs. Additionally, they can be useful to rationalize the role of current-induced forces in the mechanical deformation of one-dimensional conductors.
Structure of plate-shape nanodiamonds synthesized from chloroadamantane—are they still diamonds?
Authors: Stelmakh Svitlana , Skrobas Kazimierz , Gierlotka Stanislaw , Palosz Bogdan 
Published: February 2021

Abstract
Atomic structure of plate-shaped nanodiamonds synthesized from chloroadamantane was identified with application of large-Q powder diffraction data. Both reciprocal and real space methods of experimental data analysis were applied. Theoretical atomistic models of nanodiamonds were obtained with application of molecular dynamics (MD) simulations. It was found that examined nanodiamond samples with average grain size from 1.2 up to 2.5 nm are plates build from only six hexagonal carbon layers and they are terminated by (111)B surfaces with three dangling bonds. MD simulations showed that as a result of relaxation of surface stresses there appears a complex system of compressive and tensile strains across and parallel to the surface of the plate-nanodiamonds. Identification of the internal structure of nanodiamond was performed based on the analysis of differential interatomic distance diagrams derived from pair distribution functions G(r). Based on MD simulations an atomic model of plate-grains of diamond was elaborated. Usefulness of lattice parameters determined in a routine diffraction data analysis for characterization of nanodiamonds is questioned. As an alternative the application of the apparent lattice parameter is recommended. A dependence of the overall apparent lattice parameter 〈alp〉 on the size and shape of nanodiamond grains terminated by low index crystal faces is presented.
A deflection-based practicable method for health monitoring of in-service bridges
Authors: Prakash G 
Published: February 2021

Abstract
This paper presents a static deflection-based method for structural health monitoring of in-service bridges. In the past, the use of static as well as dynamic measurements has been investigated for damage detection in bridge elements. However, most of these methods are complex and work only in laboratory settings. Moreover, implementing such methods for in-service bridges is a challenging task. The method presented in this paper is based on a simple structural analysis principle and can be implemented for in-service bridges. Using the principle of virtual work, an analytical expression for deflection change (DC) (i.e. the difference in deflection for healthy and damaged beams) and a consistency function are derived. A plot of the DC curve reveals the damage location, and the consistency function is used to assess the damage severity. Numerical case studies and laboratory experiments are presented to investigate the effectiveness of the proposed method in different cases, such as a simply supported beam subjected to uniform loading and a cantilever beam subjected to uniform loading. Satisfactory damage localization and quantification results were achieved even with a small number of sensors. Both numerical and experimental analysis results show that the proposed model performs reasonably well at detecting and assessing the damage in bridge elements.
The calibration method of the circle-structured light measurement system for inner surfaces considering systematic errors
Authors: Dong Yuchu , Fang Changshuai , Zhu Linlin , Yan Ning , Zhang Xiaodong 
Published: February 2021

Abstract
Light plane deviation and motion direction deviation of stage systems are the two main sources of systematic errors in circle-structured light inner surface measurement systems. In this paper, we propose a new two-step calibration method to compensate these systematic errors. In the first step, a more accurate initial light plane calibration result is obtained by multi-position binocular-structured light calibration. Then, in the second step, the initial result is optimized by measuring the inner radius of a standard ring gauge to obtain the optimal light plane calibration result. Based on this result, the real motion direction is also calibrated by optimization using the inner surface scanning measurement data of the standard ring gauge. The proposed method improves the system calibration accuracy through the second calibration step, making it convenient to operate without using complex calibration targets or expensive equipment. Therefore, this calibration method has the potential to be used in actual measurements. The experimental results show that the mean relative measurement error can reach 0.015% in our homemade measurement system and validate that the measurement system calibrated by our proposed method realizes high-precision and high-repeatability measurements for inner surfaces.
Gate-tunable quantum dot formation between localized-resonant states in a few-layer MoS2
Authors: Kim Bum-Kyu , Choi Dong-Hwan , Yu Byung-Sung , Kim Minsoo , Watanabe Kenji , Taniguchi Takashi , Kim Ju-Jin , Bae Myung-Ho 
Published: February 2021

Abstract
We demonstrate a gate-tunable quantum dot (QD) located between two potential barriers defined in a few-layer MoS2. Although both local gates used to tune the potential barriers have disorder-induced QDs, we observe diagonal current stripes in current resonant islands formed by the alignment of the Fermi levels of the electrodes and the energy levels of the disorder-induced QDs, as evidence of the gate-tunable QD. We demonstrate that the charging energy of the designed QD can be tuned in the range of 2–6 meV by changing the local-gate voltages in ∼1 V.
The effect of curvature induced broken potential vorticity conservation on drift wave turbulences
Authors: Liu Z Y , Zhang Y Z , Mahajan S M 
Published: February 2021

Abstract
The correlation theory of turbulence suppression (Zhang and Mahajan 1993 Phys. Fluids
B5 2000) by velocity shear was constructed by invoking the ansatz of potential vorticity conservation (PVC) that holds for relatively simple (slab) models of drift wave turbulence. It is, therefore, surprising that a detailed modern simulation of the H mode pedestal, using the gyrokinetic code GENE (Hatch et al 2018 Plasma Phys. Control. Fusion
60 084003), found ‘striking agreement’ with the predictions of the analytic model. To understand the reasons for this remarkable agreement, an extended theory that contains finite (magnetic) curvature, and which does not conserve potential vorticity, is developed and ‘solved’ by calculating an inhomogeneous Green function reflecting the fact that the new system has a potential vorticity source. It is, then, demonstrated that the effect of the broken PVC is insignificant for the normal operation parameters in tokamaks; the correction due to curvature is at the order of

2

L
0

/

R

, where

L
0

is the scale length of the local gradient and

R

is the major radius. The excellent agreement between simulation and slab model 1993 theory is therefore not accidental; the latter can be applied with confidence to the tokamak pedestal.
A molecular dynamics study on tensile and low cycle fatigue behaviors of Ti single crystal nanowire
Authors: Ni Yang , Zhou Chuwei 
Published: February 2021

Abstract
It is essential to reveal the fatigue mechanism of the main elements in alloys at the nano scale for the material design against fatigue failure. In the present study, molecular dynamics (MD) simulations have been employed to investigate the static tensile and low cycle fatigue (LCF) behaviors of a defect free single crystal Ti nanowire with hexagonal close-packed (HCP) structure at room temperature (300 K). Results showed that the explosive initiations of body centered cubic and disordered atoms led yielding of Ti nanowire under static tensile load. The following stress response to constant amplitude cyclic strain was found strongly relatived to the instantaneous microstructure configuration at the first unloading. Variation of potential energy was used to characterize the competitions between face-centered cubic (FCC) atoms, body-centered cubic (BCC) atoms and disordered atoms. A conclusion was drew that the cyclic characteristics of Ti nanowire were heavily dependent on the dominant atom configuation during the fatigue process. Additionally, this research also found that static tensile yield strength of Ti nanowire may vary notably with respect to crystal direction, e.g. for [

1
¯

100] (or for [0001]) it is about 1.5 times of that for [11

2
¯

0].
Time-dependent reliability-based design optimization of structures with fuzzy uncertainty
Authors: Fan Chongqing , zhang Zhengkai , wen qingguo 
Published: February 2021

Abstract
For addressing the optimal design parameter for the time-dependent structure involving fuzzy variables, a novel reliability-based design optimization (RBDO) model with the constraints of time-dependent failure possibility (TDFP) is proposed. The solution of the RBDO is a double loop method, the outer loop is deterministic optimization, and the inner loop performs TDFP analysis. For evaluating TDFP in the inner loop, firstly the double-loop nested optimization method (DLOM) is investigated, but the high computational cost of DLOM is impractical, thus the single-loop optimization method is adopted. After the detailed implementation of the proposed RBDO is given, several examples containing one numerical example and two engineering examples are introduced to show the rationality of the proposed approach.
Research on Opportunity Maintenance Strategy of Wind Turbines Based on Incomplete Maintenance
Authors: Liu C , Pang R Y , Han C , Liu T T 
Published: February 2021

Abstract
Aiming at the problem of single maintenance method and high cost of wind turbines, an opportunity maintenance strategy for wind turbines based on incomplete maintenance is proposed. Firstly, based on the historical fault data of the equipment operation, the reliability of each component of the wind turbine is modeled using Weibull distribution, and the service life regression factor and failure rate increasing factor is introduced to build the incomplete maintenance strategy model of the wind turbine. Secondly, according to the opportunity maintenance theory and the reliability requirements of wind turbine components, determine the preventive maintenance reliability threshold and the opportunity maintenance reliability threshold of each component, and adopt three types of maintenance methods: incomplete repair, opportunity repair and replacement of key components within the opportunity repair interval. Based on this, a multi-component opportunity maintenance model for wind turbines based on incomplete maintenance and its decision process are constructed. Finally, the model was simulated and verified through specific wind turbine maintenance cases, and the model was solved using genetic algorithms to determine the optimal opportunity maintenance strategy. Simulation results show that the strategy can coordinate the maintenance time of various components, realize the simultaneous maintenance of multiple components, improve maintenance efficiency, and reduce maintenance costs, thereby verifying the effectiveness of the proposed strategy.
Study on the effect of laser process parameter rs on the cladding quality of camshaft
Authors: Zhang Wen-jia , Xue Jun-fang , Nan Qun-wei , Liu Tong 
Published: February 2021

Abstract
In order to study laser cladding parameters on the quality of laser cladding layer on the stability of influence, this article through the analysis of three great influence the result in the laser cladding process parameters (laser spot radius, cladding speed, laser power) of the different combination, in the WorkBench software to simulate and analyze the law of the cladding layer temperature change over time, sum up the best process parameter combination (P=1000W, V= 0.004mm/s, and R=5mm )for the actual laser cladding for guidance, to enhance the stability and reliability of the laser cladding layer.
Vaccination Strategy Analysis with SIRV Epidemic Model Based on Scale-free Networks with Tunable Clustering
Authors: Meng Xueyu , Cai Zhiqiang , Dui Hongyan , Cao Huiying 
Published: February 2021

Abstract
In this paper, we propose an SIRV (susceptible, infected, recovered, vaccination) evolutionary game model for infectious disease vaccination strategies based on the scale-free networks with tunable clustering. This model takes into account factors such as vaccination effectiveness, vaccination cost, treatment cost after illness, government subsidy rate and treatment discount rate. First of all, we use the idea of evolutionary game to make each individual in the network get two strategies, including vaccination and non-vaccination. Meanwhile, in each propagation process, according to the policy update rule (PUR), each individual updates its game strategy according to the benefit relationship with the adjacent nodes. Then, we analyze the compulsory and voluntary vaccination on the scale-free network with considering the influence of vaccination efficiency, the cost of vaccination, the cost of treatment after illness, the government subsidy rate, the treatment discount rate on vaccination. The results indicate that when the vaccination effectiveness is about 0.9, it is a better value for the evolution of vaccination strategy. For government decision making, choosing appropriate values of s and d can make the overall benefit of society higher.
Dynamics and reliability analysis of the D-knotter winding rope system
Authors: Na R S , Liu Y , Li S 
Published: February 2021

Abstract
The knotter is the core component of the rectangular bale baler. In view of the short service life, low reliability, and easy fracture during the working process, this paper takes the D-knotter’s winding rope system as the research object, lumped mass method and Lagrangain method were adopted to set up dynamic model and equations of winding rope system, Built a dynamic simulation block diagram. The dynamic response analysis of the winding rope system verified the accuracy of the dynamic differential equation and determined the fatigue analysis method. The Six Sigma reliability analysis module was used to analyze the reliability of the winding rope system, the reliability of the winding rope system at different rotational speeds was calculated, putted forward some optimizing measures for fatigue life of winding rope system, the result indicated that the fatigue life of winding rope system after optimization were greatly improved.
An adjustable envelope based EMD method for rolling bearing fault diagnosis
Authors: Hu Y F , Li Q 
Published: February 2021

Abstract
Empirical mode decomposition (EMD) can decompose complex non-stationary signals into the sum of several intrinsic mode functions (IMF), and it is widely used in fault diagnosis of mechanical devices. In order to solve the mode mixing problem and enhance the fault feature extraction ability, an adjustable envelope based EMD (AE-EMD) method was proposed. Firstly, the envelope fitting method is replaced by rational Hermite interpolation, which can effectively avoid the outstanding over and undershoot problem in the conventional fitting curve. Secondly, the optimal parameter in the AE-EMD is searched by grey wolf optimizer (GWO) using the maximum Kurtosis index as the objective function. Then, the AE-EMD method combined with the Hilbert envelope spectrum is employed to extract the fault characteristic frequency. Case study demonstrates that AE-EMD can restrain the mode mixing effectively, and it also has better fault feature extraction ability compared with the conventional EMD. This proposed method has potential significance to the fault diagnosis and condition-based maintenance (CBM) of rolling bearings in the large and complex equipment.
Optimal Design of Multi-Stress Accelerated Degradation Test within Irregular Test Region
Authors: Guo Jinyan , Yang Zhaojun , Chen Chuanhai , Tian Hailong , Luo Wei , Yu Lijuan 
Published: February 2021

Abstract
Motorized spindle is the key functional part of the computer numerical control machine tool and its lifetime determines the reliability level of the machine tool to a great extent. Many efficient plans have been obtained for electronic products but how to design an efficient accelerated degradation test plan for the motorized spindle is still a problem to be solved. In this paper, considering the condition that the loaded stresses of the motorized spindle in practice may not reach their highest levels simultaneously, a novel optimization design method of the accelerated degradation test is proposed within the irregular test region. The orthogonal design theory and the uniform design theory are applied to determine the alternative test plans within the irregular test region for different numbers of stress levels. A numerical example is presented to illustrate the effectiveness of the proposed method. Finally, the sensitivity analysis is conducted to assess the robustness of the optimum plan on parameter variation.
Failure Analysis of Intelligent Door Lock Master Control Chip
Authors: Lin Yang , Jiang Xia , Rong Li , Shiman Xiao , Huasheng Wu , Qi Peng 
Published: February 2021

Abstract
In recent years, smart door locks having password keyboards, fingerprint recognition and communicating function have seen explosive growth. A large number of enterprises engaged in the manufacture of the intelligent door locks, followed by the associated after-sales problems, and the product without power, no reaction phenomenon caused by the failure of master control chip is relatively common, which greatly affects the user experience. In this paper, a mainstream smart door lock products on the market as the research object, a series of failure analysis and root cause search were executed to find the reasons of failure. The research shows that the main reason for the non-power supply and non-response of the intelligent door lock after sale is the fault of the main control chip. The main control chip fails due to the lack of electrostatic protection, which is directly related to the improper production and assembly process.
Reliability Assessment of Machine Tools Considering Multi-effects of Working Conditions
Authors: Hu Wei , Yang Zhaojun , Chen Chuanhai , Wu Yue , Xie Qunya , Zhu Xiaocui 
Published: February 2021

Abstract
Undertaking varying working conditions is common for a machine tool. One single reliability model for determining a single effect is not suitable for the reliability evaluation of machine tools due to the multi-effect of working conditions on the reliability of machine tools. This paper proposes a generalized model using hazard functions and Weibull distribution to assess the reliability of machine tools under different effects of working conditions. This model considers three effects, including the proportional hazard, time, and additive hazard effects. The distribution of time effect is discussed. Furthermore, a secure parameter estimation method is presented to calculate the proposed reliability model. A case study based on field data is presented. The proposed model is compared with classical reliability models. The result shows that the proposed model has better goodness of fit for the realistic cumulative distribution of machine tools.
A short review of reliability-based design optimization
Authors: Dawei ZHU , Jinyu ZHOU , Chunqiu LIU , Zhiling WANG 
Published: February 2021

Abstract
Reliability-based design optimization (RBDO) has become an important branch of reliability engineering after decades of development. In recent years, reliability optimization design methods considering uncertain factors have emerged in an endless stream. This article summarizes the research status and basic principles of RBDO problems. According to the different RBDO methods, the mathematical models of the double-loop method, single-loop method, and decoupling method and their respective advantages and disadvantages are detailed from the perspective of the optimization process. It also focuses on the analysis of several kinds of RBDO bottleneck problems, and discusses the existing related methods and possible solutions.