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Kinematic deformation and intensity assessment of the 2021 Maduo M_(S)7.4 earthquake in Qinghai revealed by high-frequency GNSS
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作者 Yu Li Yuebing Wang +2 位作者 Lijiang Zhao Hongbo Shi Pingping Wang 《Geodesy and Geodynamics》 EI CSCD 2024年第3期230-240,共11页
Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advance... Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advancement of GNSS observation and data processing makes it play an important role in this field,especially the high-frequency GNSS.We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the M_(S)7.4 Maduo earthquake epicenter.The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained.The results show that:1)Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter.Coseismic response deformation on the east and west sides shows bilateral asymmetry,which markedly differs from the symmetry presented by surface rupture.2)The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area,although the former is generally slightly smaller than the latter.3)There may exist obstacles on the eastern side of the seismogenic fault.The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault(KPJF)and Maqin-Maqu segment,resulting in higher seismic risk in the future. 展开更多
关键词 Maduo earthquake high-frequency GNSS Kinematic deformation Seismic intensity
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Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment
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作者 Dawei Ruan Mingwei Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期821-844,共24页
The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is ... The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the foundation.The high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe cases.This article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element model.By proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through coupling.Taking into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are obtained.The validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance region.The design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel. 展开更多
关键词 Tunnel equipment high-frequency units startup conditions transient dynamics dynamic response foundation design
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Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding
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作者 Thomas Lesser Frank Wolfram +1 位作者 Conny Braun Reiner Gottschall 《World Journal of Experimental Medicine》 2024年第1期88-99,共12页
BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is ... BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion. 展开更多
关键词 One-lung ventilation Unilateral superimposed high-frequency jet ventilation One-lung flooding
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Therapeutic efficacy of methylprednisolone sodium succinate via diverse administration routes for mid-to high-frequency sudden sensorineural hearing loss
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作者 Xiang-Da Meng Ting-Ting Li Li-Min Deng 《World Journal of Clinical Cases》 SCIE 2024年第18期3321-3331,共11页
BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use o... BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use of methylprednisolone sodium succinate(MPSS)via different administration routes,in combination with conventional medications,remains a topic of interest.AIM To compare the therapeutic efficacy of MPSS administered via different routes in combination with conventional drugs for the treatment of mid-to high-frequency SSNHL.METHODS The medical records of 109 patients with mid-to high-frequency SSNHL were analyzed.The patients were divided into three groups based on the route of administration:Group A[intratympanic(IT)injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection],Group B(intravenous injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection),and Group C(single IT injection of MPSS).The intervention effects were compared and analyzed.RESULTS The posttreatment auditory thresholds in Group A(21.23±3.34)were significantly lower than those in Groups B(28.52±3.36)and C(30.23±4.21;P<0.05).Group A also exhibited a significantly greater speech recognition rate(92.23±5.34)than Groups B and C.The disappearance time of tinnitus,time to hearing recovery,and disappearance time of vertigo in Group A were significantly shorter than those in Groups B and C(P<0.05).The total effective rate in Group A(97.56%)was significantly greater than that in Groups B and C(77.14%and 78.79%,χ^(2)=7.898,P=0.019).Moreover,the incidence of adverse reactions in Groups A and C was significantly lower than that in Group B(4.88%,3.03%vs 2.57%,χ^(2)=11.443,P=0.003),and the recurrence rate in Group A was significantly lower than that in Groups B and C(2.44%vs 20.00%vs 21.21%,χ^(2)=7.120,P=0.028).CONCLUSION IT injection of MPSS combined with conventional treatment demonstrates superior efficacy and safety compared to systemic administration via intravenous infusion and a single IT injection of MPSS.This approach effectively improves patients'hearing and reduces the risk of disease recurrence. 展开更多
关键词 Sudden loss of hearing at middle-and high-frequency of the descending type Methylprednisolone sodium succinate Intratympanic injection Intravenous injection
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Radio-frequency measurements of energetic-electron-driven emissions using high-frequency magnetic probe on XuanLong-50 spherical torus
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作者 王明远 伦秀春 +3 位作者 薄晓坤 刘兵 刘阿娣 石跃江 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期33-38,共6页
A high-frequency magnetic probe is designed and developed on the XuanL ong-50(EXL-50)spherical torus to measure high-frequency magnetic field fluctuation.The magnetic loop,radio filters,radio-frequency limiter,and dat... A high-frequency magnetic probe is designed and developed on the XuanL ong-50(EXL-50)spherical torus to measure high-frequency magnetic field fluctuation.The magnetic loop,radio filters,radio-frequency limiter,and data acquisition system of the probe are comprehensively examined.The fluctuation data from the EXL-50 plasma are analyzed in the time–frequency domain using fast Fourier transforms.Moreover,distinct high-frequency instabilities are detected using this diagnostic system.In particular,significant frequency chirping is observed,which is consistent with the bumpon-tail drive instability predicted using the Berk–Breizman model. 展开更多
关键词 high-frequency magnetic probe high-frequency instabilities XuanLong-50
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Tuning magneto-dielectric properties of Co_(2)Z ferrites via Gd doping for high-frequency applications
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作者 武剑 卢冰 +6 位作者 张颖 陈一鑫 孙凯 陈大明 李强 刘颖力 李颉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期468-473,共6页
Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,an... Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,and 0.20)materials are successfully prepared by using solid-state method at 925℃for 4 h with 2.5-wt%Bi_(2)O_(3)sintering aids.The content of Gd^(3+)ion can affect micromorphology,grain size,bulk density,and magneto-dielectric properties of the ferrite.With Gd^(3+)ion content increasing,saturation magnetization(Ms)first increases and then decreases.The maximum value of Ms is 44.86 emu/g at x=0.15.Additionally,sites occupied by Gd^(3+)ions can change magnetic anisotropy constant of the ferrite.Magnetocrystalline anisotropy constant(K_1)is derived from initial magnetization curve,and found to be related to spin-orbit coupling and intersublattice interactions between metal ions.The real part of magnetic permeability(μ′)and real part of dielectric permittivity(ε′)are measured in a frequency range of 10 MHz-1 GHz.When x=0.15,material has excellent magneto-dielectric properties(μ′≈12.2 andε′≈17.61),low magnetic loss(tanδμ≈0.03 at 500 MHz),and dielectric loss(tanδε≈0.04 at 500 MHz).The results show that Gd-doped Co_(2)Z ferrite has broad application prospects in multilayer filters and high-frequency antennas. 展开更多
关键词 Co_(2)Z ferrite magneto-dielectric properties Gd doping high-frequency applications
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Nullors, and Nullor Circuits;There Applications in Symbolic Circuit Analysis and Design
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作者 Reza Hashemian 《Applied Mathematics》 2024年第1期33-45,共13页
The objective in this presentation is to introduce some of the unique properties and applications of nullors in active circuit analysis and designs. The emphasis is to discuss the role nullors can play in symbolic rep... The objective in this presentation is to introduce some of the unique properties and applications of nullors in active circuit analysis and designs. The emphasis is to discuss the role nullors can play in symbolic representation of transfer functions. To show this we adopt the topological platform for the circuit analysis and use a recently developed Admittance Method (AM) to achieve the Sum of Tree Products (STP), replacing the determinant and cofactors of the Nodal Admittance Matrix (NAM) of the circuit. To construct a transfer function, we start with a given active circuit and convert all its controlled sources and I/O-ports to nullors. Now, with a solid nullor circuit (passive elements and nullors) we first eliminate the passive elements through AM operations. This produces the STPs. Second, the all-nullor circuit is then used to find the signs or the STPs. Finally, the transfer function (in symbolic, if chosen) is obtained from the ratio between the STPs. 展开更多
关键词 Admittance Method Analog circuits Nullors Nullor circuits Sum of Tree Products Transfer Functions
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Interplay between topology and localization on superconducting circuits
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作者 关欣 霍炳燕 陈刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期240-246,共7页
Topological insulators occupy a prominent position in the realm of condensed matter physics. Nevertheless, the presence of strong disorder has the potential to disrupt the integrity of topological states, leading to t... Topological insulators occupy a prominent position in the realm of condensed matter physics. Nevertheless, the presence of strong disorder has the potential to disrupt the integrity of topological states, leading to the localization of all states.This study delves into the intricate interplay between topology and localization within the one-dimensional Su–Schrieffer–Heeger(SSH) model, which incorporates controllable off-diagonal quasi-periodic modulations on superconducting circuits.Through the application of external alternating current(ac) magnetic fluxes, each transmon undergoes controlled driving,enabling independent tuning of all coupling strengths. Within a framework of this model, we construct comprehensive phase diagrams delineating regions characterized by extended topologically nontrivial states, critical localization, and coexisting topological and critical localization phases. The paper also addresses the dynamics of qubit excitations, elucidating distinct quantum state transfers resulting from the intricate interplay between topology and localization. Additionally, we propose a method for detecting diverse quantum phases utilizing existing experimental setups. 展开更多
关键词 TOPOLOGY LOCALIZATION superconducting circuits
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Quantum algorithm for minimum dominating set problem with circuit design
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作者 张皓颖 王绍轩 +2 位作者 刘新建 沈颖童 王玉坤 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期178-188,共11页
Using quantum algorithms to solve various problems has attracted widespread attention with the development of quantum computing.Researchers are particularly interested in using the acceleration properties of quantum a... Using quantum algorithms to solve various problems has attracted widespread attention with the development of quantum computing.Researchers are particularly interested in using the acceleration properties of quantum algorithms to solve NP-complete problems.This paper focuses on the well-known NP-complete problem of finding the minimum dominating set in undirected graphs.To expedite the search process,a quantum algorithm employing Grover’s search is proposed.However,a challenge arises from the unknown number of solutions for the minimum dominating set,rendering direct usage of original Grover’s search impossible.Thus,a swap test method is introduced to ascertain the number of iterations required.The oracle,diffusion operators,and swap test are designed with achievable quantum gates.The query complexity is O(1.414^(n))and the space complexity is O(n).To validate the proposed approach,qiskit software package is employed to simulate the quantum circuit,yielding the anticipated results. 展开更多
关键词 quantum algorithm circuit design minimum dominating set
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Neuromorphic circuits based on memristors: endowing robots with a human-like brain
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作者 Xuemei Wang Fan Yang +7 位作者 Qing Liu Zien Zhang Zhixing Wen Jiangang Chen Qirui Zhang Cheng Wang Ge Wang Fucai Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期47-63,共17页
Robots are widely used,providing significant convenience in daily life and production.With the rapid development of artificial intelligence and neuromorphic computing in recent years,the realization of more intelligen... Robots are widely used,providing significant convenience in daily life and production.With the rapid development of artificial intelligence and neuromorphic computing in recent years,the realization of more intelligent robots through a pro-found intersection of neuroscience and robotics has received much attention.Neuromorphic circuits based on memristors used to construct hardware neural networks have proved to be a promising solution of shattering traditional control limita-tions in the field of robot control,showcasing characteristics that enhance robot intelligence,speed,and energy efficiency.Start-ing with introducing the working mechanism of memristors and peripheral circuit design,this review gives a comprehensive analysis on the biomimetic information processing and biomimetic driving operations achieved through the utilization of neuro-morphic circuits in brain-like control.Four hardware neural network approaches,including digital-analog hybrid circuit design,novel device structure design,multi-regulation mechanism,and crossbar array,are summarized,which can well simulate the motor decision-making mechanism,multi-information integration and parallel control of brain at the hardware level.It will be definitely conductive to promote the application of memristor-based neuromorphic circuits in areas such as intelligent robotics,artificial intelligence,and neural computing.Finally,a conclusion and future prospects are discussed. 展开更多
关键词 neuromorphic devices neuromorphic circuits hardware networks MEMRISTORS humanlike robots
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Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform
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作者 娄小平 昝慧茹 徐雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期247-253,共7页
This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a... This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement techniques.The QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding phase.This innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely implemented.Unlike existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation process.To assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud platform.The results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind signatures.Furthermore,we have established authentic security thresholds(82.102%)in the presence of real noise,thereby emphasizing the practicality of our proposed solution. 展开更多
关键词 proxy blind signature quantum circuits quantum computation IBM quantum cloud platform
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Analysis of multiple-faults of high-voltage circuit breakers based on non-negative matrix decomposition
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作者 Yongrong Zhou Zhaoxing Ma +1 位作者 Hao Chen Ruihua Wang 《Global Energy Interconnection》 EI CSCD 2024年第2期179-189,共11页
High-voltage circuit breakers are the core equipment in power networks,and to a certain extent,are related to the safe and reliable operation of power systems.However,their core components are prone to mechanical faul... High-voltage circuit breakers are the core equipment in power networks,and to a certain extent,are related to the safe and reliable operation of power systems.However,their core components are prone to mechanical faults.This study proposes a component separation method to detect multiple mechanical faults in circuit breakers that can achieve online real-time monitoring.First,a model and strategy are presented for obtaining mechanical voiceprint signals from circuit breakers.Subsequently,the component separation method was used to decompose the voiceprint signals of multiple faults into individual component signals.Based on this,the recognition of the features of a single-fault voiceprint signal can be achieved.Finally,multiple faults in high-voltage circuit breakers were identified through an experimental simulation and verification of the circuit breaker voiceprint signals collected from the substation site.The research results indicate that the proposed method exhibits excellent performance for multiple mechanical faults,such as spring structures and loose internal components of circuit breakers.In addition,it provides a reference method for the real-time online monitoring of high-voltage circuit breakers. 展开更多
关键词 High voltage circuit breaker Signal separation MONITOR Multiple faults Power system
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A study on characteristic indexesof railway ballast bed underhigh-frequency radar
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作者 Shilei Wang Zhan Peng +2 位作者 Guixian Liu Weile Qiang Chi Zhang 《Railway Sciences》 2023年第1期33-47,共15页
Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of rai... Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of railway ballast bed.Design/methodology/approach–Based on original radar signals,the time–frequency characteristics of radar signals were analyzed,five ballast bed condition characteristic indexes were proposed,including the frequency domain integral area,scanning area,number of intersections with the time axis,number of timedomain inflection points and amplitude envelope obtained by Hilbert transform,and the effectiveness and sensitivity of the indexes were analyzed.Findings–The thickness of ballast bed tested at the sleep bottom by high-frequency radar is up to 55 cm,which meets the requirements of ballast bed detection.Compared with clean ballast bed,the values of the five indexes of fouled ballast bed are larger,and the five indexes could effectively show the condition of the ballast bed.The computational efficiency of amplitude envelope obtained by Hilbert transform is 140 s$km1,and the computational efficiency of other indexes is 5 s$km1.The amplitude envelopes obtained by Hilbert transform in the subgrade sections and tunnel sections are the most sensitive,followed by scanning area.The number of intersections with the time axis in the bridge sections was the most sensitive,followed by the scanning area.The scanning area can adapt to different substructures such as subgrade,bridges and tunnels,with high comprehensive sensitivity.Originality/value–The research can provide appropriate characteristic indexes from the high-frequency radar original signal to quantitatively evaluate ballast bed condition under different substructures. 展开更多
关键词 Ballasted track Ballast bed high-frequency radar TEST Time–frequency characteristics Characteristic indexes
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Understanding the correlation between energy-state mismatching and open-circuit voltage loss in bulk heterojunction solar cells
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作者 Hyun-Seock Yang Danbi Kim +7 位作者 Chang-Mok Oh Vellaiappillai Tamilavan Pesi MHangoma Hojun Yi Bo RLee Insoo Shin In-Wook Hwang Sung Heum Park 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期164-174,共11页
Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires ener... Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires energy-state matching between the donor and acceptor at the BHJ interfaces.Thus,both geometrically and energetically accessible delocalized state matching at the hot energy level is crucial for achieving efficient PICT.In this study,an effective method for quantifying the hot state matching of OPVs was developed.The degree of energy-state matching between the electron donor and acceptor at BHJ interfaces was quantified using a mismatching factor(MF)calculated from the modified optical density of the BHJ.Furthermore,the correlation between the open-circuit voltage(Voc)of the OPV device and energy-state matching at the BHJ interface was investigated using the calculated MF.The OPVs with small absolute MF values exhibited high Voc values.This result clearly indicates that the energy-state matching between the donor and acceptor is crucial for achieving a high Voc in OPVs.Because the MF indicates the degree of energy-state matching,which is a critical factor for suppressing energy loss,it can be used to estimate the Voc loss in OPVs. 展开更多
关键词 bulk heterojunction open circuit voltage organic photovoltaics photoinduced charge transfer voltage loss
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Electromagnetic Performance Analysis of Variable Flux Memory Machines with Series-magnetic-circuit and Different Rotor Topologies
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作者 Qiang Wei Z.Q.Zhu +4 位作者 Yan Jia Jianghua Feng Shuying Guo Yifeng Li Shouzhi Feng 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期3-11,共9页
In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor topologies.Based on a V-type VFM machine,five topologies... In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor topologies.Based on a V-type VFM machine,five topologies with different interior permanent magnet(IPM)arrangements are evolved and optimized under same constrains.Based on two-dimensional(2-D)finite element(FE)method,their electromagnetic performance at magnetization and demagnetization states is evaluated.It reveals that the iron bridge and rotor lamination region between constant PM(CPM)and variable PM(VPM)play an important role in torque density and flux regulation(FR)capabilities.Besides,the global efficiency can be improved in VFM machines by adjusting magnetization state(MS)under different operating conditions. 展开更多
关键词 Memory machine Permanent magnet Rotor topologies Series magnetic circuit Variable flux
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Total ionizing dose effect modeling method for CMOS digital-integrated circuit
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作者 Bo Liang Jin-Hui Liu +3 位作者 Xiao-Peng Zhang Gang Liu Wen-Dan Tan Xin-Dan Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期32-46,共15页
Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID eff... Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID effects in complementary metaloxide semiconductor(CMOS)digital ICs based on the input/output buffer information specification(IBIS)was proposed.The digital IC was first divided into three parts based on its internal structure:the input buffer,output buffer,and functional area.Each of these three parts was separately modeled.Using the IBIS model,the transistor V-I characteristic curves of the buffers were processed,and the physical parameters were extracted and modeled using VHDL-AMS.In the functional area,logic functions were modeled in VHDL according to the data sheet.A golden digital IC model was developed by combining the input buffer,output buffer,and functional area models.Furthermore,the golden ratio was reconstructed based on TID experimental data,enabling the assessment of TID effects on the threshold voltage,carrier mobility,and time series of the digital IC.TID experiments were conducted using a CMOS non-inverting multiplexer,NC7SZ157,and the results were compared with the simulation results,which showed that the relative errors were less than 2%at each dose point.This confirms the practicality and accuracy of the proposed modeling method.The TID effect model for digital ICs developed using this modeling technique includes both the logical function of the IC and changes in electrical properties and functional degradation impacted by TID,which has potential applications in the design of radiation-hardening tolerance in digital ICs. 展开更多
关键词 CMOS digital-integrated circuit Total ionizing dose IBIS model Behavior-physical hybrid model Physical parameters
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Fluid-chemical modeling of the near-cathode sheath formation process in a high current broken in DC air circuit breaker
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作者 彭世东 李静 +3 位作者 段薇 曹云东 刘树鑫 黄浩 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期523-538,共16页
When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop thr... When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop through the near-electrode sheath is an important means to build up the arc voltage, which directly determines the current-limiting performance of the DCCB. A numerical model to describe the near-electrode sheath formation process can provide insight into the physical mechanism of the arc formation, and thus provide a method for arc energy regulation. In this work, we establish a two-dimensional axisymmetric time-varying model of a medium-voltage DCCB arc when interrupted by high current based on a fluid-chemical model involving 16 kinds of species and 46 collision reactions. The transient distributions of electron number density, positive and negative ion number density, net space charge density, axial electric field, axial potential between electrodes, and near-cathode sheath are obtained from the numerical model. The computational results show that the electron density in the arc column increases, then decreases, and then stabilizes during the near-cathode sheath formation process, and the arc column's diameter gradually becomes wider. The 11.14 V–12.33 V drops along the17 μm space charge layer away from the cathode(65.5 k V/m–72.5 k V/m) when the current varies from 20 k A–80 k A.The homogeneous external magnetic field has little effect on the distribution of particles in the near-cathode sheath core,but the electron number density at the near-cathode sheath periphery can increase as the magnetic field increases and the homogeneous external magnetic field will lead to arc diffusion. The validity of the numerical model can be proven by comparison with the experiment. 展开更多
关键词 near-cathode sheath atmospheric pressure air arc fluid-chemical model high current DC air circuit breaker(DCCB)
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Improved high-frequency equivalent circuit model based on distributed effects for SiGe HBTs with CBE layout
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作者 孙亚宾 李小进 +1 位作者 张金中 石艳玲 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期502-508,共7页
In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors(HBTs) with a CBE layout, where we consider the distributed effects along the base region. The actua... In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors(HBTs) with a CBE layout, where we consider the distributed effects along the base region. The actual device structure is divided into three parts: a link base region under a spacer oxide, an intrinsic transistor region under the emitter window,and an extrinsic base region. Each region is considered as a two-port network, and is composed of a distributed resistance and capacitance. We solve the admittance parameters by solving the transmission-line equation. Then, we obtain the smallsignal equivalent circuit depending on the reasonable approximations. Unlike previous compact models, in our proposed model, we introduce an additional internal base node, and the intrinsic base resistance is shifted into this internal base node,which can theoretically explain the anomalous change in the intrinsic bias-dependent collector resistance in the conventional compact model. 展开更多
关键词 SiGe heterojunction bipolar transistors(HBT) small-signal equivalent circuit distributed effects CBE layout
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6-35 SFC High-frequency Signal Input Circuit Fault Analysis
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作者 Jin Peng Su Xueming +4 位作者 Xu Zhe Wang Xianwu Zhang Ruifeng Lan Tao Tian Ruixia 《IMP & HIRFL Annual Report》 2014年第1期290-290,共1页
The Dee voltage of the RF cavity in cyclotron HIRFL-SFC is not high enough when resonance frequency is8.536 MHz. By repeatedly measuring and adjusting the parameters of the cavity and transmitter tank circuit, Deevolt... The Dee voltage of the RF cavity in cyclotron HIRFL-SFC is not high enough when resonance frequency is8.536 MHz. By repeatedly measuring and adjusting the parameters of the cavity and transmitter tank circuit, Deevoltage can only be added to 40 kV, which doesn't meet the physical requirement of 80 kV.One output port of the RF divider is open circuit in the process of inspection which was discovered occasionally.SFC signal comes from the SSC,which is divided into two (see Fig. 1) , but the one open suspension through 4.4m 50 Ω coaxial cable and don't connect the load. After removing the cable from the divider, the Dee voltage ofSFC could be added to 70 kV easily. At the same time the value of amplitude stability gain is lower than usual, theinput signal amplitude that is too high. The value changes from 240 to 440 mV when measuring the input signalwith an oscilloscope, the reason is caused by 4.4 m terminal open line. The analysis and conclusions are as follows. 展开更多
关键词 FREQUENCY SIGNAL circuit
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基于MSPA-MCR-CIRCUIT的山西省运城市景观生态网络构建
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作者 许涛 樊鹤翔 +2 位作者 周可钦 李涵璟 王苗 《中国园林》 CSCD 北大核心 2024年第3期114-118,共5页
山西省运城市位于黄河中下游三省交界处,其景观要素成分复杂,对运城景观生态网络斑块与廊道的研究有利于黄河生态系统稳定性的保护。基于形态空间格局理论(MSPA)确定连通性强的核心斑块,识别核心生态源地,以最小累计阻力模型(MCR)为基础... 山西省运城市位于黄河中下游三省交界处,其景观要素成分复杂,对运城景观生态网络斑块与廊道的研究有利于黄河生态系统稳定性的保护。基于形态空间格局理论(MSPA)确定连通性强的核心斑块,识别核心生态源地,以最小累计阻力模型(MCR)为基础,叠加7种阻力因子构建综合阻力面,根据重力模型划分生态廊道等级。以基于电路理论(CIRCUIT)的Linkage Mapper工具识别生态夹点和障碍点作为生态节点,综合构建源地(面)-廊道(线)-节点(点)的运城市景观生态网络。结果表明:1)运城市核心生态源地有9处,综合重力模型和实际建设需求划分13条重要生态廊道和10条一般生态廊道,识别出关键生态节点17个,一般生态节点34个;2)现有重要生态廊道集中于运城南部,南北方向生态联系较弱,可优先加强贯穿稷山县、新绛县、闻喜县的重要生态廊道建设;3)MSPA模型与电路理论的综合运用可提升景观生态网络构建的科学性和准确性,有利于确定生态修复关键区域,为生态修复项目的布局提供有力支撑。 展开更多
关键词 风景园林 景观生态网络 形态空间格局理论 最小累计阻力模型 电路理论 源地-廊道-节点
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