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Fourier and wavelet transformations application to fault detection of induction motor with stator current

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Journal of Central South University 2010年第1期17卷 93-101页

作者： LEE Sang-hyuk 王一奇 song jung-il School of Mechatronics Changwon National University

Fault detection of an induction motor was carried out using the information of the stator current. After synchronizing the actual data, Fourier and wavelet transformations were adopted in order to obtain the sideband or detail value characteristics under healthy and various faulty operating conditions. The most reliable phase current among the three phase currents was selected using an approach that employs the fuzzy entropy measure. Data were trained with a neural network system, and the fault detection algorithm was verified using the unknown data. Results of the proposed approach based on Fourier and wavelet transformations indicate that the faults can be properly classified into six categories. The training error is 5.3×10-7, and the average test error is 0.103.

关键词： Fourier transformation wavelet transformation induction motor fault detection

Finite element and experimental analysis of Vickers indentation testing on Al_2O_3 with diamond-like carbon coating

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Journal of Central South University 2012年第5期19卷 1175-1181页

作者： ZHAI Jian-guang WANG Yi-qi KIM Tae-gyu song jung-il Department of Mechanical Engineering Changwon National University Changwon 641-773 Korea Department of Nanosystem and Nanoprocess Engineering Pusan National University Pusan 609-735 Korea

Numerical simulation and experimental study of the Vickers indentation testing of the Al2O3 ceramic coated by diamond-like carbon(DLC) layer were *** numerical analysis was implemented by a two-dimensional finite element(FE) axis symmetry *** analysis results gave insight into the fracture mechanism of DLC films coated on brittle ceramic(Al2O3) *** maximum principal stress field was used to locate the most expected area for crack formation and propagation during the Vickers indentation *** results show that the median crack initiates in the interface under indenter,before ring crack occurs as the indenter presses ***,the plastic deformation appears when the indenter penetrates into the *** thicker DLC coating increases the Vickers hardness and fracture toughness.

关键词： Vickers indentation testing finite element diamond-like carbon Al2O3 fracture toughness

Optimizing electrophoretic deposition conditions for enhancement in electrical conductivity of carbon fiber/carbon nanotube/epoxy hybrid composites

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Journal of Central South University 2012年第11期19卷 3017-3022页

作者：王一奇 BYUN Joon-hyung KIM Byung-sun song jung-il Department of Mechanical Engineering Changwon National University Changwon 641-773 Korea Korea Institute of Materials Science Changwon 641-831 Korea

The effectiveness of optimizing electrical conductivity of carbon fiber/carbon nanotube （CNT）/epoxy hybrid composites via Taguchi method was demonstrated. CNTs were induced on carbon fabric by electrophoretic deposition （EPD） technique. The essential deposition parameters were identified as l） the deposition time, 2） the deposition voltage, 3） the mass fraction of CNTs in suspension, and 4） the distance between the electrodes. An experimental design was then performed to establish the appropriate levels for each factor. An orthogonal array of L9 （34） was designed to conduct the experiments. Electrical conductivity results were collected as the response. The relative influences of design parameters on the response were discussed. Using the model, signal to noise （S/N） ratio and response characteristics for the optimized deposition parameter combination were predicted. The results show clearly that the optimum condition of electrophoretic deposition （EPD） process improves the electrical conductivity of carbon/epoxy hybrid composites.

关键词： design of experiment electrophoretic deposition carbon nanotube Taguchi method signal to noise (S/N) ratio analysisof variance (ANOVA)

Dry sliding wear behavior of Al_2O_3 fiber and SiC particle reinforced aluminium based MMCs fabricated by squeeze casting method

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Transactions of Nonferrous Metals Society of China 2011年第7期21卷 1441-1448页

作者：王一奇宋正日朝国昌原国立大学机械工程学院

Al2O3 fiber （Al2O3f） and SiC particle （SiCp） hybrid metal matrix composites （MMCs） were fabricated by squeeze casting *** tests were carried out using a pin-on-disk friction and wear tester by sliding these pin specimens at a constant speed of 0.36 m/s （570 r/min） against a steel counter disk at room temperature,100 C and 150 C,*** observe the wear characteristics and investigate the wear mechanism,the morphologies of the worn surfaces and specific wear rate were analyzed by using scanning electron microscope （SEM） and Arrhenius ***,the effects of fiber orientation and hybrid ratio were discussed.

关键词： metal matrix composites dry sliding wear wear resistance friction of coefficient

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： song Jiang Congwen Zhu Ning Jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

Sand-polished Kapton film and aluminum as source of electron transfer triboelectric nanogenerator through vertical contact separation mode

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International Journal of Smart and Nano Materials 2020年第1期11卷 38-46页

作者： Ravi Kumar Cheedarala jung il song Research Institute of Mechatronics Department of Mechanical EngineeringChangwon National UniversityUichang-guChangwon CityS.Korea

Contact electrification is a direct triboelectrification method for producing current through charge transfer when two different differentiated materials have brought into *** the first time,we developed a simple triboelectric nanogenerator(TENG)where the electronic charges were realized through contact separation mode between sand-polished Kapton(SPK)and Al ***,we demonstrated the energetic interfacial contact between these surfaces and observed satisfactory output *** novel SPK-TENG produced 40 V and 2.8μA,of open-circuit voltages(V_(oc))and short-circuit currents(Isc)at 4 Hz,***,the SPK-TENG was dramatically increased up the performance of TENG,up to 40% of V_(oc) and 42% of I_(sc),with respect to the Kapton film because the mobility of electrons is very high on the device surface compared to the other pristine Kapton *** fabricated SPK-TENGs were good candidates for satisfying the need for alternative contact separation mode TENGs.

关键词： Kapton contactelectrification K-Al TENG SPK-Al TENGs electron transfer mechanism

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Inspires effective alternatives to backpropagation:predictive coding helps understand and build learning

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Neural Regeneration Research 2025年第11期20卷 3215-3216页

作者： Zhenghua Xu Miao Yu Yuhang song School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjinChina Department of Computer Science University of OxfordOxfordUK

Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human *** enable learning by brain and machine,it is essential to accurately identify and correct the prediction errors,referred to as credit assignment(Lillicrap et al.,2020).It is critical to develop artificial intelligence by understanding how the brain deals with credit assignment in neuroscience.

关键词： assignment learning enable

Neuronal regulated cell death in aging-related neurodegenerative diseases:key pathways and therapeutic potentials

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Neural Regeneration Research 2025年第8期20卷 2245-2263页

作者： Run song Shiyi Yin Jiannan Wu Junqiang Yan Department of Neurology The First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyangHenan ProvinceChina Neuromolecular Biology Laboratory The First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyangHenan ProvinceChina

Regulated cell death(such as apoptosis,necroptosis,pyroptosis,autophagy,cuproptosis,ferroptosis,disulfidptosis)involves complex signaling pathways and molecular effectors,and has been proven to be an important regulatory mechanism for regulating neuronal aging and ***,excessive activation of regulated cell death may lead to the progression of aging-related *** review summarizes recent advances in the understanding of seven forms of regulated cell death in age-related ***,the newly identified ferroptosis and cuproptosis have been implicated in the risk of cognitive impairment and neurodegenerative *** forms of cell death exacerbate disease progression by promoting inflammation,oxidative stress,and pathological protein *** review also provides an overview of key signaling pathways and crosstalk mechanisms among these regulated cell death forms,with a focus on ferroptosis,cuproptosis,and *** instance,FDX1 directly induces cuproptosis by regulating copper ion valency and dihydrolipoamide S-acetyltransferase aggregation,while copper mediates glutathione peroxidase 4 degradation,enhancing ferroptosis ***,inhibiting the Xc-transport system to prevent ferroptosis can increase disulfide formation and shift the NADP^(+)/NADPH ratio,transitioning ferroptosis to *** insights help to uncover the potential connections among these novel regulated cell death forms and differentiate them from traditional regulated cell death *** conclusion,identifying key targets and their crosstalk points among various regulated cell death pathways may aid in developing specific biomarkers to reverse the aging clock and treat age-related neurodegenerative conditions.

关键词： apoptosis autophagy cuproptosis disulfidptosis ferroptosis necroptosis neurodegenerative disease neurological aging diseases PANoptosis pyroptosis