bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research On Sensorless Control Of Permanent Magnet Synchronous Motor
Authors: Li Haohao , Chen Qigong , Xie Wei , Lei Shouzhong 
Published: January 2022

Abstract
Aiming at the problem that there is no position sensor to observe the rotor position and speed of the built-in permanent magnet synchronous motor under the traditional method of high frequency rotating voltage signal injection, the estimation accuracy of rotor position and speed is low because of the use of a variety of filters in the signal demodulation process. The generalized second-order integrator is used to replace the traditional filters to extract the high frequency response current. In order to reduce the filtering delay problem existing in the traditional signal demodulation method, a new signal demodulation method is proposed, and the rotor position estimation is compensated with appropriate phase compensation. At the same time, appropriate phase compensation is carried out for the estimation of rotor position By constructing IPMSM sensorless vector control simulation module in Simulink simulation, compared with the traditional high-frequency injection method, the improved algorithm can estimate the rotor magnetic pole position more accurately and faster in the process of sensorless control of the motor in the low speed range, and has better stability introduction.
Simulation of master-slave optimal synchronous control of double motors based on Simulink
Authors: Zhang Nan , Wu Shiling , Jia Yijun , An Zhaozhe 
Published: January 2022

Abstract
In the working process of vibration machinery, as the output device of power source, the synchronous running state of motor has a decisive influence on the working efficiency of vibration machinery. This paper mainly studies the control synchronization of the double-mass vibration system driven by two motors. Firstly, the dynamic model of the vibration system is established and the vertical displacement equation of the vibration system is derived. Secondly, using adaptive model and PD control algorithm, the controller of motor in vibration system is designed to achieve accurate control of motor and eccentric block motion. Finally, the vibration synchronization effect of the control system and the effectiveness of the control system are verified by modeling and simulation with MATLAB/Simulink software. The test results show that when the main motor is in different initial phases, the variable parameter controller can achieve the control synchronization of the main motor and the slave motor in a short time and achieve a better control synchronization effect. Relevant research results can provide theoretical basis for the design of double-motor vibration machinery.
Vibration pile driving system based on Sliding Mode Control
Authors: An Zhaozhe , Zhang Nan , Jia Yijun 
Published: January 2022

Abstract
The sliding mode variable structure synchronous control of vibration pile driving system driven by double DC motors is studied. Firstly, the model of double machine driven vibratory pile driving system is established, and the theoretical derivation of system synchronization and stability is carried out. Secondly, the sliding mode variable structure control method is used to realize the phase speed synchronous control of two motors in the vibration system. Finally, Simulink is used to verify the correctness of the theoretical derivation, and the vibration displacement of the pile driving system is simulated and analyzed. The research shows that the sliding mode variable structure control can realize the synchronous control of the double machine driven vibratory pile driving system, which provides a theoretical and practical engineering basis for the design of this type of vibratory pile driving system.
Uncertainty quantification and global sensitivity analysis for composite cylinder shell via data-driven polynomial chaos expansion
Authors: Chen Ming , Zhang Xinhu , Shen Kechun , Pan Guang 
Published: January 2022

Abstract
The mechanical properties of composite material exhibit inherent variation with uncertainty. Uncertainties in material properties propagate and result in uncertainties of mechanical performance of structure made of composite material. Polynomial chaos expansion (PCE) is implemented to carry out uncertainty quantification (UQ) and global sensitivity analysis (GSA) of cylinder shell made of composite material for this paper. A case study concerning eigenvalue buckling load of composite cylinder shell is investigated. Design of experiment (DOE) is conducted by utilizing Latin hypercubic sampling. Then data-driven PCE is established and later validated. Statistical moments (mean and standard deviation) and Sobol sensitivity indices of eigenvalue buckling load are obtained respectively. It is found that the PCE can serve as an efficient approach to handle UQ and GSA in engineering applications.
Study on prediction model of surface roughness of SiCp/Al composites based on Neural Network
Authors: Sun Hao , Zhang Chaochao , Li Yikai , Yin Tingting , Zhang Hanming , Pu Jin 
Published: January 2022

Abstract
In order to effectively meet the actual industrial production standards and improve the prediction accuracy of composite surface roughness, a prediction model of SiCp/Al composite surface roughness based on neural network is proposed. The influence parameters of surface roughness of SiCp/Al composites are analyzed from the cutting tool parameters, and the mathematical calculation of surface roughness of SiCp/Al composites is carried out. Using neural network technology, by determining various parameters of neural network, collecting and processing various data of material surface, the surface roughness prediction model of SiCp/Al composite is constructed to realize the surface roughness prediction of SiCp/Al composite. The experimental results show that the maximum error between the actual value and the predicted value of the surface roughness of composite materials from the prediction model established in this paper is only 0.013, and the average error percentage between the actual value and the predicted value is 0.705%, which can effectively improve the prediction accuracy of the surface roughness of composite materials and meet the standards of actual industrial production.
Uniformity of response of Uranium fission chambers used as neutron beam monitors
Authors: Lafont F. , Guerard B. , Hall-Wilton R. , Kanaki K. 
Published: January 2022

Abstract
Uranium fission chambers are commonly used for neutron beam
monitoring in neutron research facilities. The challenges brought
with the renewing or commissioning of new neutron facilities
encourage to minimize the interaction between the monitor and the
neutron beam. In order to characterize both their detection
efficiency and transmission factor, several fission chambers, have
been scanned on the CT1 monochromatic beam line of the ILL. Results
show that the monitor transparency, measured at the center of the
monitor, varies from 90% to 96%, and that the detection efficiency
varies by as much as 50% over the active area.
Ultrafast high energy electron lens radiography suitable for transient electromagnetic field diagnosis
Authors: Xiao J.H. , Du Y.C. , Li H.Q. , Zhao Y.T. , Sheng L. 
Published: January 2022

Abstract
Transient electromagnetic fields — during or after
laser/particle beam-target interaction — are a significant and
hardly explored parameter. This paper proposes a new method for
measuring transient electromagnetic fields, based on ultrafast
high-energy electron lens radiography, that has a high tolerance for
matter in the diagnosed region. With this method, a continuous point
strength diagnosis helps to obtain delicate. Furthermore, dual-band
diagnosis can be used to determine the field direction. To verify
its feasibility, a 50 MeV electron lens radiography beamline was
designed and optimized and a preliminary simulation for diagnosing
circular magnetic fields ranging from 170 T·μm to
680 T·μm was performed. For a number density of
2000/pixel and ±10% non-uniformity, ±15% diagnostic
field strength accuracy has been obtained. The direction diagnosis
also works well. Combined with the advantages of high-energy
electron beams, ultrafast high-energy electron lens radiography is
suitable for transient electromagnetic field diagnosis.
Feasibility of neutral particle analysis for fast-ion measurements at W7-X
Authors: Bannmann S. , Bozhenkov S. , Äkäslompolo S. , Poloskei P. , Schneider W. , Ford O. , Wolf R.C. 
Published: January 2022

Abstract
A preliminary study investigating capabilities of a planned
but not yet installed neutral particle analyzer
(NPA) [1,2] system combined with a
diagnostic neutral beam at Wendelstein 7-X
(W7-X) [3] is
presented. Additionally two NPAs viewing the neutral beam injection
(NBI) [4] source 8 beam and using it as neutral
source are studied. The main focus is laid on what information about
NBI fast-ion slowing down distributions can be inferred from active
NPA measurements when altering the magnetic configuration, plasma
β, density, electron temperature or radial electric field. For
an order of magnitude estimation of the passive signal a model for
penetration of neutral hydrogen recycling from the first wall is
implemented. For the active signal a diagnostic neutral beam
injector was simulated using FIDASIM [5]. The
fast-ion slowing down distributions were calculated with
ASCOT [6].

The synthetic NPA signal is found in general to be sensitive to
changes in the fast-ion distribution function. Distinct features can
be seen in the high energy active signal in the high-mirror
configuration when changing β, especially, when looking at
deeply trapped fast particles. However, for the initially planned
installation geometry of the NPA diagnostic most fast-ion
distributions exhibit only small differences in the magnitude and
especially shape. In a high density case in the standard magnetic
configuration with a central β of 8%, the fast-ion density in
the core region is too low to provide a measurable flux of charge
exchanged neutrals. The passive signal from the inner plasma regions
is found to be negligible compared to the active signal.
Design and development of the S-band high power test stand for multi-purpose applications at IHEP
Authors: Liu J.D. , Zhou Z.S. , Gan N. , He X. , He D.Y. , Ma X.P. , Wang S.C. , Dong D. , Zhang J.R. , Li J.Y. 
Published: January 2022

Abstract
A multipurpose S-band high-power test stand (HPTS) developed
at the Institute of High Energy Physics (IHEP) of China is routinely
used for radio-frequency (RF) conditioning of couplers and resonant
structures, as well as other high-power experiments in the S-band
frequency regime. The HPTS with a peak power of 230 MW was
developed to meet requirements of various applications with multiple
frequencies (2856 MHz/2998 MHz) and power levels
(45 MW/50 MW/65 MW/80 MW) for different accelerator projects at
the IHEP, e.g. the High Energy Photon Source (HEPS), Beijing
Electron Positron Collider (BEPCII), Circular Electron Positron
Collider (CEPC).

This paper describes the design and implementation of the system in
detail. The highlight of the HPTS is the impedance-matched design to
accommodate different impedances, allowing a single pulse modulator
to supply different types of klystron loads. The control system,
developed under the Experimental Physics and Industrial Control
System (EPICS), adopts a combination of Micro Telecommunications
Computing Architecture (MTCA) based low-level RF system (LLRF) and
programmable logic controller (PLC) based interlock unit
controllers, and enables a real-time data acquisition and
visualization. To ensure a high reliability and high-gradient RF
power conditioning, the interlock unit integrates various protection
features, like the short circuit load, high standing wave ratio, low
vacuum, arcing detector, and abnormal dark current. It is worth
mentioning that the entire conditioning procedure can be performed
unattended automatically controlled. The test stand has been
operated stably for more than 7,000 hours for many rounds of
high-power RF conditioning with different power/frequency
requirements, which indicates that the HPTS can provide a stable,
reliable, and automatic high-power testing for the development of
S-band related devices.
Exact and approximate mean first passage times on trees and other necklace structures: a local equilibrium approach
Authors: Förster Yanik-Pascal , Gamberi Luca , Tzanis Evan , Vivo Pierpaolo , Annibale Alessia 
Published: January 2022

Abstract
In this work we propose a novel method to calculate mean first-passage times (MFPTs) for random walks on graphs, based on a dimensionality reduction technique for Markov state models, known as local-equilibrium (LE). We show that for a broad class of graphs, which includes trees, LE coarse-graining preserves the MFPTs between certain nodes, upon making a suitable choice of the coarse-grained states (or clusters). We prove that this relation is exact for graphs that can be coarse-grained into a one-dimensional lattice where each cluster connects to the lattice only through a single node of the original graph. A side result of the proof generalises the well-known essential edge lemma (EEL), which is valid for reversible random walks, to irreversible walkers. Such a generalised EEL leads to explicit formulae for the MFPTs between certain nodes in this class of graphs. For graphs that do not fall in this class, the generalised EEL provides useful approximations if the graph allows a one-dimensional coarse-grained representation and the clusters are sparsely interconnected. We first demonstrate our method for the simple random walk on the c-ary tree, then we consider other graph structures and more general random walks, including irreversible random walks.
Investigation of the mechanical response and deformation mechanism of cortical bone material under combined compression and bending loads
Authors: Sun Xingdong , Xu Ke , Wang Jie , Xu Liangyuan , Fang Liangfei , Jiang Rui , Yang Yingchun 
Published: January 2022

Abstract
Objective service load is the load pattern of cortical bone in practical conditions. The objective service load conditions of cortical bone are complicated, usually including two or more load patterns. The mechanical behavior and deformation mechanism of cortical bone material under coupling load pattern and single load pattern are diametrically different. However, nowadays, researches on the mechanical response of cortical bone have been heavily focused on the single load pattern, which couldn’t reveal the potential deformation mechanism accurately. For the purpose of obtaining the objective mechanical properties under complicated loading patterns, the mechanical response and deformation mechanism of bone material under compression-bending coupling load were investigated by in-situ test. The research shows that bending strength increased under the compression-bending coupling load than the single bending load. By in-situ observation, the variations of surface strain distribution and cracks directions were the potential reasons for the increase of the bending strength. It was found that the cracks changed from transverse fracture to integrated patterns with transverse fracture and longitudinal fracture. Larger fracture range and tortuous crack propagation increased the fracture energy dissipation, which led to an enlarged bending strength under the compression-bending coupling load. Through theoretical analysis and numerical calculation, the impeded effect to the increasing of bending deflection was dominant before the final fracture with the adding of the compression load. The numerical calculation result was consistent with the result of the experiment. This present work would provide new references to further studies on the mechanical behavior of cortical bone under complicated loading patterns.
Synthesis and structural analysis of beta cobalt hydroxide (ß-CoOH) nanosheets derived from ZIF 67 metal-organic framework
Authors: Manimegalai M , Annaraj J 
Published: January 2022

Abstract
In the present work, a facile synthesis of beta-cobalt hydroxide (ß-CoOH) nanosheets from ZIF-67 structure using thermolysis method has been described. The cobalt hydroxide nanosheets grown on carbon cloth would be highly benificial for wide-ranging applications including catalysis and batteries. The XRD studies show that the crystallite sizes are below 100 nanometers for both the ZIF structure and the derived CoOH. The compositional analysis shows that cobalt contributed more to the weight percentage. FESEM images reveal that cobalt nanosheets were grown on the carbon fiber. Also, the TEM images show that nanosheets morphology has been exhibited on the surface of carbon cloth because of the CoOH coating. Further, the chemical composition and purity of the (ß-CoOH) nanosheets on CC were perceived using EDX and XPS analyses.
Synergistic effects of Y and Nd on grain refinement of Mg-Y-Nd-Al alloy
Authors: Zhao Lili , Wang Liping , Wang Lei , Feng Yicheng , Fan Rui , Zhao Sicong , Fu Yuanke 
Published: January 2022

Abstract
In this study, the synergistic effects of Y and Nd on the grain refinement of the as-cast Mg-Y-Nd-Al alloy was investigated by varying Y and Nd contents while fixing their total content (Y + Nd) at 7%. When the contents of Y and Nd were 3% and 4%, respectively, the refinement was most effective and the smallest grain size of 49 ± 5 μm was achieved. The grain refinement process was primarily controlled by the heterogeneous nucleation and the growth restriction factor (Q value). Y could only form Al2RE phase with Al, while both Al2RE and Al11RE3 were formed between Nd and Al. The Al2RE phase acted as nucleation particles of α-Mg and facilitated heterogeneous nucleation; however, Al11RE3 was an unfavorable phase for heterogeneous nucleation. When the Y content was less than 3%, the quantity of Al2RE phase increased when more Y was available, which resulted in more active nucleation particles and better refinement. When the Y content exceeded 3%, the Q value (growth limiting factor) of the alloy decreased, while the quantity of Al2RE phase remained unchanged. This would lead to a decreased number of active nucleation particles and a less effective grain refinement.
Simple precipitation method to reduce the particle size of glutinous rice flour: physicochemical evaluation
Authors: Takarini Veni , Asri Lia A T W , Djustiana Nina , Hadi Bambang Kismono 
Published: January 2022

Abstract
Submicron- and nano-sized starch can be employed as organic filler particles in composites. Starch with this size range can be used as an alternative filler for dental impression materials that are used to create an accurate replica or mold of the hard and soft oral tissues. In this work we selected glutinous rice flour as a starch source comprising a high amylopectin content. We carried out two different precipitation methods to reduce the particle size of glutinous rice flour and evaluated the changes on the particle size, morphological, crystallinity, and thermal properties. First precipitation method involved addition of ethanol into an aqueous phase consisting of flour and water, while in the second method (instant precipitation) we added the aqueous phase into the ethanol organic phase. We observed that both methods lead to the decrease of the glutinous rice flour crystallinity from 21.85% to around 4.30%–10.99%. The precipitation also decreased the gelatinization temperature of the treated filler particles from 87.7℃ to around 80.3–85.3℃. We found the morphological transition of glutinous rice flour from polyhedral to nearly spherical-shaped particles. First method resulted in agglomerated particles that were not perfectly distributed. While by employing the instant precipitation method we successfully reduced the particle size from 3411.5 nm to 259.5 nm. To conclude, instant precipitation method offers a simple route to reduce the particle size of glutinous rice flour to submicron-sized range.
Enhanced current path by circularly and periodically-aligned semiconducting single-walled carbon nanotubes for logic circuit device
Authors: Park Boik , Jang Jongsu , Kim Hyeonggyu , Seo Jiseok , Yoo Hyunjun , Kim Taehoon , Hong Yongtaek 
Published: January 2022

Abstract
Improving the performance of solution-processed single-walled carbon nanotube thin film transistors (SWCNT TFTs) is essential to their wide usage in next generation large-area electronic devices. However, uncontrollable tube-tube junction and random network formation from conventional solution processes of SWCNTs has limited mobility and on-current level of SWCNT TFTs. Herein, we demonstrate a facile method by switching idea of reducing coffee-ring of the conventionally solution-processed or inkjet-printed thin films. Spontaneous coffee-ring formation of the inkjet-printed droplets is found to enhance directional alignment of SWCNTs in the outer rim of the coffee-rings. The evaporation-driven capillary flow toward the rim inside induces migration of SWCNT and thus forms densely aligned SWCNT rings. Periodic connection of such rings can provide high-current path at a given voltage. Therefore, by additionally forming the periodically connected rings on a pre-established random network of SWCNT in channel area of TFTs, we significantly improved the mobility and I
on/I
off ratio of SWCNT TFTs without degradations in other electrical parameters such as threshold voltage and subthreshold swing. We also demonstrated all-solution-processed inverters with higher voltage-gain in comparison with conventional ones.
Monitoring thermal defects in rail and rail joints using piezo impedance-based structural health monitoring (PISHM)
Authors: Banerjee Tathagata , Moharana Sumedha 
Published: January 2022

Abstract
Rail track derailment has been proven to be the cause of most of the rail accidents in recent years. High-temperature strains in railways caused by rail traction and thermal variation are the main causes of derailment, which lead to buckling. The likelihood of passenger deaths and maintenance costs will be reduced if thermal strains and failure in rails are detected early. This research attempts to provide a preventative strategy for detecting thermal strains and deformation caused by temperature fluctuations at railways. Using the electromechanical impedance (EMI) technique, piezoelectric sensors were used to acquire piezo coupled structural signatures for lab-sized rail samples, i.e. plain rail and rail joints, for gradual temperature escalation and repeat heat cycle. The experimental conductance signatures were obtained for the incremental rise in temperature (30–80 °C) in ambient conditions, and repetitive thermal cycles. To better diagnose structural problems induced only by the effect of heat on the host structure, thermal compensation is proposed. The piezo–coupled signatures for thermal changes in rail and rail junctions (weld and bolt) were found to be particularly effective in detecting incipient structural alterations for both steady and cyclic temperature variations. Statistical damage index was used to quantify the damage for all types of rail-joint bar caused due to temperature variation. Overall, this study has paved an experimental technique that can be used to detect early damage in rail and rail joints due to thermal loading.