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Coupling simulation of hydrodynamic tunneling effect induced by beam impact in high-power accelerators
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作者 Wei Zhang Chao-Fan An +5 位作者 Yong Wang Jian Li Yuan Chen Zhi-Xin Tan Tao Yang Yuan-Cun Nie 《Nuclear Science and Techniques》 2026年第5期228-240,共13页
Under certain accident conditions in particle accelerators,high-power beam irradiation may damage vacuum pipes,magnets,and other key equipment.Therefore,machine protection for high-power accelerators is critical to en... Under certain accident conditions in particle accelerators,high-power beam irradiation may damage vacuum pipes,magnets,and other key equipment.Therefore,machine protection for high-power accelerators is critical to ensure safe operation.It is important to study radiation damage to materials to support the design and operation of machine protection systems.In the shock-wave regime,a pronounced hydrodynamic tunneling effect occurs within materials.The traditional one-way coupling simulation method results in substantial errors in this regime.Therefore,a bidirectional iterative coupling simulation method was developed.This method enables the bidirectional coupling of the Monte Carlo code FLUKA and the thermodynamic program Ansys-Autodyn.Density changes are monitored during the simulations,and the updated density is promptly fed back to FLUKA.The program remodels the target with the new density distribution to calculate the new energy deposition distribution,which is then returned to Autodyn for subsequent simulations.This iterative process continues until the entire beam has completed the energy deposition process.Compared to existing methods,this automated method significantly improves the efficiency of the coupled simulations and reduces the possibility of human error.The HRMT-12 beam irradiation experiment at CERN was used for a benchmark study,and simulations were conducted and compared using different equations of state.The results demonstrate the efficiency and accuracy of this simulation method.Compared to complex and costly beam irradiation experiments,this approach is expected to provide fast and cost-effective scientific guidance for the machine protection of high-power accelerators.Considering the severe consequences of the hydrodynamic tunneling effect,machine protection components such as beam collimators,absorbers,and dump blocks should adopt low-density materials to reduce the energy deposition density.Beam dilution may be required in beam dumping systems to avoid target damage.This method can be applied to the redundancy design of such beam dumping systems. 展开更多
关键词 High-power accelerators Machine protection Irradiation damage Monte Carlo simulation Thermodynamic response
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Production of ^(287,288)Mc isotopes in the ^(48)Ca+^(243)Am reaction at China Accelerator Facility for Superheavy Elements
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作者 X.Y.Huang Z.Y.Zhang +38 位作者 J.G.Wang L.Ma C.L.Yang M.H.Huang X.L.Wu Z.G.Gan H.B.Yang M.M.Zhang Y.L.Tian Y.S.Wang J.Y.Wang Y.H.Qiang G.Xie S.Y.Xu Z.Zhao Z.C.Li L.C.Sun L.Zhu X.Zhang H.Zhou F.Guan Z.H.Li W.X.Huang Z.Qin Y.Wang X.J.Yin Y.F.Cui Z.W.Lu Y.He L.T.Sun Z.Z.Ren S.G.Zhou V.K.Utyonkov A.A.Voinov Yu.S.Tsyganov A.N.Polyakov D.I.Solovyev N.D.Kovrizhnykh M.V.Shumeiko 《Chinese Physics Letters》 2026年第1期9-16,共8页
We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-... We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-2(SHANS2),a gas-filled recoil separator located at the China Accelerator Facility for Superheavy Elements(CAFE2).In total,20 decay chains are attributed to ^(288)Mc and 1 decay chain is assigned to ^(287)Mc.The measured oa-decay properties of ^(287,288)Mc as well as its descendants are consistent with the known data.No additional decay chains originating from the 2n or 5n reaction channels were detected.The excitation function of the ^(243)Am(^(48)Ca,3n)^(288)Mc reaction was measured at the cross-section level of picobarn,which indicates the promising capability for the study of heavy and superheavy nuclei at the facility. 展开更多
关键词 spectrometer heavy atoms fusionevaporation reaction China accelerator Facility Superheavy Elements PRODUCTION decay chains ISOTOPES ca am reaction mc
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Effect of High-Intensity Interval Training on Muscle Strength Growth in Athletes
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作者 Yang Jiao 《Journal of Contemporary Educational Research》 2025年第10期408-414,共7页
High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence ... High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence to analyze mechanisms of HIIT in neuromuscular activation,hormonal responses,muscle fiber adaptation,and metabolic pathway effects.It focuses on its effectiveness in enhancing explosive power,maximum strength,and strength endurance,while also examining the integration of HIIT with traditional resistance training,periodized programming,and personalized prescription.Scientific implementation of HIIT can effectively diversify or even replace conventional strength training,not only offering positive directional changes for strength development but also introducing innovative approaches to sports performance training practices. 展开更多
关键词 high-intensity interval training Muscle strength ATHLETES Intervention effect
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Impacts of High-Intensity Interval Training on Aerobic Capacity, Walking and Balance Function in Stroke Survivors
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作者 Xueli XIANG 《Medicinal Plant》 2025年第5期55-59,66,共6页
[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of ... [Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of Science,SPORTSDiscus,PsycINFO,SCOPUS,CINAHL)up to May 2025.Seventeen randomized controlled trials(RCTs;total n=1142)met inclusion criteria:adults with stroke,device-based HIIT(≥70%HRR/VO 2peak),and outcomes assessing VO_(2)peak,6-min walk distance(6MWD),or Berg Balance Scale(BBS).Methodological quality was evaluated using the PEDro scale.Pooled effect sizes(Hedges'g)were calculated via random-effects models,with heterogeneity quantified by I^(2).[Results]HIIT significantly improved peak oxygen uptake(VO_(2)peak)versus controls(g=0.59,95%CI:0.44-0.75,p<0.001;I^(2)=16.29%).Low heterogeneity and symmetrical funnel plots supported robustness.HIIT also enhanced walking endurance(6MWD:g=0.32,95%CI:0.16-0.48,p<0.01;I^(2)=30%).In contrast,no significant benefit was observed for balance function(BBS:g=0.07,95%CI:-0.13-0.26,p=0.50;I^(2)=0%).[Conclusions]HIIT is a safe and highly effective intervention for enhancing aerobic capacity and walking function post-stroke.Its benefits are maximized at higher intensities and longer durations but do not extend to balance improvement.Integrating HIIT into stroke rehabilitation protocols is strongly recommended to promote functional independence. 展开更多
关键词 high-intensity Interval Training(HIIT) Aerobic capacity WALKING BALANCE Stroke survivors
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Plan for a super η factory at Huizhou accelerator complex
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作者 Xurong Chen Xiong-Hong He +9 位作者 Qiang Hu De-Xu Lin Yang Liu Hao Qiu Xu Sun Ye Tian Rong Wang Hong-Lin Zhang Ya-Peng Zhang Cheng-Xin Zhao 《Nuclear Science and Techniques》 2025年第8期138-153,共16页
As an approximate Goldstone boson with zero quantum number and zero standard model charge,the long-lived η meson exhibits the decay processes that offer a unique opportunity to explore physics beyond the standard mod... As an approximate Goldstone boson with zero quantum number and zero standard model charge,the long-lived η meson exhibits the decay processes that offer a unique opportunity to explore physics beyond the standard model and new sources of charge parity violation.Further,they facilitate the testing of the low-energy quantum chromodynamics theory and measurement of the fundamental parameters of light quarks.To pursue these goals,we propose a plan to construct a super ηfactory at HIAF high-energy terminal or at CiADS after its energy upgrade.The high-intensity proton beam at HIAF enables the production of many η samples,exceeding 1013events per year during the first stage,utilizing multiple layers of thin targets composed of light nuclei.This paper presents the physics goals,the first-version conceptual design of the spectrometer,and preliminary simulation results. 展开更多
关键词 high-intensity frontier Eta meson factory New physics Symmetry breaking Strong interaction Silicon-pixel detector
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Design of insulation support system of 120 keV positive ion source accelerator
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作者 Wen DENG Yahong XIE +5 位作者 Yuming GU Yunfei JIANG Longbin LIU Fang WANG Jianglong WEI Chundong HU 《Plasma Science and Technology》 2025年第1期128-133,共6页
In order to support the physical research on the EAST tokamak,a new positive ion source with designed beam energy of 120 keV was proposed to be developed.Accelerator structure is one of the key components of the ion s... In order to support the physical research on the EAST tokamak,a new positive ion source with designed beam energy of 120 keV was proposed to be developed.Accelerator structure is one of the key components of the ion source.Through the finite element analysis method,the electrostatic analyses of insulators and grid plates were carried out,the material and structure parameters of insulators were determined.The maximum electric field around each insulator is about 4 kV/mm,and the maximum electric field between grids is about 14 kV/mm,which can meet the 120 keV withstand voltage holding.The insulation system for the positive ion source accelerator with 120 keV is designed,and the connection and basic parameters of insulators and support flanges are analyzed and determined. 展开更多
关键词 positive ion source accelerator insulation support system electrostatic simulation
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ParaGraph:a parallel graph computing accelerator based on software-hardware collaboration
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作者 DENG Junyong KANG Yuchun +2 位作者 YE Zekun ZHU Yun JIA Yanting 《High Technology Letters》 2025年第2期105-117,共13页
Graph computing has become pervasive in many applications due to its capacity to represent complex relationships among different objects in the big data era.However,general-purpose architectures are computationally in... Graph computing has become pervasive in many applications due to its capacity to represent complex relationships among different objects in the big data era.However,general-purpose architectures are computationally inefficient for graph algorithms,and dedicated architectures can provide high efficiency,but lack flexibility.To address these challenges,this paper proposes ParaGraph,a reduced instruction set computing-five(RISC-V)-based software-hardware co-designed graph computing accelerator that can process graph algorithms in parallel,and also establishes a performance evaluation model to assess the efficiency of co-acceleration.ParaGraph handles parallel processing of typical graph algorithms on the hardware side,while performing overall functional control on the software side with custom designed instructions.ParaGraph is verified on the XCVU440 field-programmable gate array(FPGA)board with E203,a RISC-V processor.Compared with current mainstream graph computing accelerators,ParaGraph consumes 7.94%less block RAM(BRAM)resources than ThunderGP.Its power consumption is reduced by 86.90%,24.90%,and 76.38%compared with ThunderGP,HitGraph,and GraphS,respectively.The power efficiency of connected components(CC)and degree centrality(DC)algorithms is improved by an average of 6.50 times over ThunderGP,2.51 times over HitGraph,and 3.99 times over GraphS.The software-hardware co-design acceleration performance indicators H/W.Cap for CC and DC are 13.02 and 14.02,respectively. 展开更多
关键词 graph computing software-hardware co-design reduced instruction set computing-five(RISC-V) parallel accelerator
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Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries
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作者 Yawei Xiao Qianqian Gu +2 位作者 Haoyu Li Mengyao Li Yude Wang 《Journal of Energy Chemistry》 2025年第1期377-384,共8页
Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been d... Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices. 展开更多
关键词 Internal electric field Cationic accelerator lon diffusion kinetics Cathode modification strategy Aqueous zinc ion battery
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Compact RF linear accelerator for electron beam irradiation applications at PBP-CMU Electron Linac Laboratory
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作者 Monchai Jitvisate Pittaya Apiwattanakul +3 位作者 Noppadol Kangrang Jatuporn Saisut Chitrlada Thongbai Sakhorn Rimjaem 《Nuclear Science and Techniques》 2025年第4期45-58,共14页
A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear acce... A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear accelerator.The main components include a thermionic DC electron gun,an RF linear accelerator,a beam diagnostic chamber,and a beam exit window for electron beam irradiation.Therefore,reengineering must be performed based on the characteristics of the electron beam and its dynamics throughout the system.In this study,the electron beam current density emitted from the cathode was calculated based on the thermionic emission theory,and the result was used to produce the electron beam distribution in the gun using CST Studio Suite^(■)software.The properties of the electron beam and its acceleration in the linear accelerator and downstream diagnostic section were studied using the ASTRA electron beam dynamics simulation code,with the aim of producing an electron beam with an average energy of 4 MeV at the linear accelerator exit.The transverse beam profile and electron deposition dose in the ambient environment were calculated using Geant4 Monte Carlo simulation software to estimate the beam performance for the irradiation experiments.The parameters studied can be used as guidelines for machine operation and future experimental plans. 展开更多
关键词 Thermionic electron gun RF linear accelerator Electron dynamics simulation Monte Carlo simulation Electron beam irradiation Electron beam processing Deposition dose
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Cosmic Acceleration and the Hubble Tension from Baryon Acoustic Oscillation Data
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作者 Xuchen Lu Shengqing Gao Yungui Gong 《Chinese Physics Letters》 2026年第1期327-332,共6页
We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parame... We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parameter E(z)from the DESI BAO Alcock-Paczynski(AP)data using Gaussian process to perform the null test.We find strong evidence of accelerated expansion from the DESI BAO AP data.By reconstructing the deceleration parameter q(z) from the DESI BAO AP data,we find that accelerated expansion persisted until z■0.7 with a 99.7%confidence level.Additionally,to provide insights into the Hubble tension problem,we propose combining the reconstructed E(z) with D_(H)/r_(d) data to derive a model-independent result r_(d)h=99.8±3.1 Mpc.This result is consistent with measurements from cosmic microwave background(CMB)anisotropies using the ΛCDM model.We also propose a model-independent method for reconstructing the comoving angular diameter distance D_(M)(z) from the distance modulus μ,using SNe Ia data and combining this result with DESI BAO data of D_(M)/r_(d) to constrain the value of r_(d).We find that the value of r_(d),derived from this model-independent method,is smaller than that obtained from CMB measurements,with a significant discrepancy of at least 4.17σ.All the conclusions drawn in this paper are independent of cosmological models and gravitational theories. 展开更多
关键词 baryon acoustic oscillation bao data cosmic accelerated expansion dimensionless hubble parameter reconstructing deceleration parameter null testwe accelerated expansion null tests gaussian process
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Interfacial Evolution and Accelerated Aging Mechanism for LiFePO_(4)/Graphite Pouch Batteries Under Multi-Step Indirect Activation
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作者 Yun Liu Jinyang Dong +11 位作者 Jialong Zhou Yibiao Guan Yimin Wei Jiayu Zhao Jinding Liang Xixiu Shi Kang Yan Yun Lu Ning Li Yuefeng Su Feng Wu Lai Chen 《Nano-Micro Letters》 2026年第4期735-754,共20页
The dissolution of iron from the cathode and electrode/electrolyte interface(EEI)during long cycles significantly accelerates the aging process of LiFePO_(4)(LFP)/graphite batteries;there is a lack of systematic under... The dissolution of iron from the cathode and electrode/electrolyte interface(EEI)during long cycles significantly accelerates the aging process of LiFePO_(4)(LFP)/graphite batteries;there is a lack of systematic understanding of the spatial distribution of the EEI interface layer and the dissolve of Fe ions,especially in terms of the mechanism of the cathode-electrolyte interphase(CEI),solid electrolyte interphase(SEI),and iron dissolution.In this study,aged cells were subjected to continuous activation with constant current and multi-step segmented indirect activation(IA)and analyzed for capacity fade,impedance growth,and active Li^(+)mass loss at the EEI and nanoscale levels.The interaction between dissolved Fe^(2+)and the EEI in LFP/graphite pouch batteries was proposed and verified.The findings indicate that during IA process,the electric field facilitates the migration of solvated ions toward the electrodes,while simultaneously inhibiting the formation of organic species such as ROCO_(2)Li.The SEI primarily consists of a mixture of organic and inorganic small molecules,forming a continuous and uniform film on the electrode surface.This study demonstrates that IA favors the formation of a uniform EEI and offers constructive insights for advancing accelerated lifetime prediction strategies in lithium-ion batteries. 展开更多
关键词 accelerated aging Electrode/electrolyte interface Multi-step segmented indirect activation EEI film Dissolve of Fe ions
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Effects of initial spin orientation on the generation of polarized electron beams from laser wakefield acceleration in plasma
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作者 L.R.Yin X.F.Li +6 位作者 Y.J.Gu N.Cao Q.Kong M.Büscher S.M.Weng M.Chen Z.M.Sheng 《Matter and Radiation at Extremes》 2026年第1期20-28,共9页
The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of... The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of the initial spin direction,the spin dynamics of the electron beam are found to depend on the self-injection mechanism.The effects of wakefields and laser fields are studied using test particle dynamics and particle-in-cell simulations based on the Thomas-Bargmann-Michel-Telegdi equation.Compared with transverse injection,longitudinal injection is found to be preferable for obtaining a highly polarized electron beam. 展开更多
关键词 spin dynamics laser fields test particle dynamics initial spin orientation electron beam laser wakefield acceleration electron beam polarization
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Resilient self-centering viscous-based bracing with SMA and friction springs:Multi-objective control of displacement and acceleration-an analytical study
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作者 Navid Rahgozar M.Shahria Alam 《Resilient Cities and Structures》 2026年第1期133-150,共18页
Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,th... Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,thereby reducing post-earthquake repair costs and contributing to seismic resilience.However,non-structural components,particularly those sensitive to floor acceleration,remain vulnerable,resulting in prolonged func-tional recovery times.This paper aims to address this limitation by introducing a novel structural archetype,the Self-Centering Viscous-Based Braced Frame(SC-VBBF),which integrates superelastic shape memory alloy(SMA)bars,viscous dampers(VDs),and friction springs(FSs).A streamlined analytical approach relies on the strength decoupling of VD from other components using aλfactor to design SC-VBBFs.To evaluate the effectiveness of the hybrid brace,a set of 4-,8-,and 12-story archetypes equipped with SC-PBBs and SC-VBBFs are simulated in OpenSees and analyzed under various earthquake types,including crustal,subcrustal,and subduction events.The results demonstrate the superior performance of the SC-VBBF withλ≤0.5 system compared to SC-PBBFs in mitigating floor accelerations under design-level earthquakes and improving seismic resilience. 展开更多
关键词 SELF-CENTERING Piston-based braced frame Self-centering viscous-based brace Shape memory alloy Viscous damper Friction spring Seismic analysis Design procedure acceleration control
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Optimizing CNN Class Granularity for Power-Efficient Edge AI in Sudden Unintended Acceleration Verification
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作者 HeeSeok Choi Joon-Min Gil 《Computers, Materials & Continua》 2026年第5期1723-1742,共20页
Given the growing number of vehicle accidents caused by unintended acceleration and braking failure,verifying Sudden Unintended Acceleration(SUA)incidents has become a persistent challenge.A central issue of debate is... Given the growing number of vehicle accidents caused by unintended acceleration and braking failure,verifying Sudden Unintended Acceleration(SUA)incidents has become a persistent challenge.A central issue of debate is whether such events stem frommechanical malfunctions or driver pedalmisapplications.However,existing verification procedures implemented by vehiclemanufacturers often involve closed tests after vehicle recalls;thus raising ongoing concerns about reliability and transparency.Consequently,there is a growing need for a user-driven framework that enables independent data acquisition and verification.Although previous studies have addressed SUA detection using deep learning,few have explored howclass granularity optimization affects power efficiency and inference performance in real-time Edge AI systems.To address this problem,this work presents a cloud-assisted artificial intelligence(AI)solution for the reliable verification of SUA occurrences.The proposed system integrates multimodal sensor streams including camera-based foot images,On-Board Diagnostics II(OBD-II)signals,and six-axismeasurements to determine whether the brake pedal was actually engaged at themoment of a suspected SUA.Beyond image acquisition,convolutional neural network(CNN)models perform real-time inference to classify the driver’s pedal operation states with the resulting outputs transmitted and archived in the cloud.A dedicated dataset of brake and accelerator pedal images was collected from 15 vehicles produced by 6 domestic and international manufacturers.Using this dataset,transfer learning techniques were applied to compare and analyze model performance and generalization as the CNN class granularity varied from coarse to fine levels.Furthermore,classification performance was evaluated in terms of latency and power efficiency under different class configurations.The experimental results demonstrated that the proposed solution identified the driver’s pedal behavior accurately and promptly,with the two-class model achieving the highest F1-score and accuracy among all granularity settings. 展开更多
关键词 Edge artificial intelligence(Edge AI) real-time inference sudden unintended acceleration(SUA) convolutional neural networks(CNNs) class granularity optimization pedal placement analysis
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Asymmetric ion acceleration in laser-produced magnetized collisionless shocks
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作者 Tianyi Zhang Ao Guo +8 位作者 Huibo Tang Guangyue Hu Kai Huang Shuoting Shao Shunyi Yang Jiayin Xie Gaoyuan Peng Peng E Quanming Lu 《Matter and Radiation at Extremes》 2026年第2期65-73,共9页
Quasi-hemispherical magnetized collisionless shocks have been generated at the SG-II laser facility through the interaction between a laserproduced supersonic plasma flow and a magnetized ambient plasma,exhibiting an ... Quasi-hemispherical magnetized collisionless shocks have been generated at the SG-II laser facility through the interaction between a laserproduced supersonic plasma flow and a magnetized ambient plasma,exhibiting an angular asymmetric shock profile accompanied by asymmetric ion acceleration.We have conducted test particle simulations using the electromagnetic fields derived from 2D MHD simulations to investigate the asymmetry of ion acceleration.The simulations reproduce the angular asymmetry of the shock and the ion acceleration observed in experiments.The results indicate that shock drift acceleration is the primary mechanism for ion energization in the present quasiperpendicular magnetized shock.The asymmetric shock structure caused by nonuniform ambient plasma forms an asymmetric accelerated electric field,ultimately leading to angular asymmetric ion acceleration,which is consistent with space observations and our experimental results.Our study provides a plausible explanation for the discrepancies reported in previous ion acceleration experiments,and could contribute to understanding of the collisionless shock acceleration. 展开更多
关键词 test particle simulations electromagnetic fields d mhd simulations asymmetric ion acceleration supersonic plasma flow laser produced magnetized collisionless shocks angular asymmetric shock profile asymmetric ion accelerationwe
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Production of light nuclei and hypernuclei at High Intensity Accelerator Facility energy region 被引量:7
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作者 Peng Liu Jin-Hui Chen +1 位作者 Yu-Gang Ma Song Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期84-90,共7页
Heavy-ion collisions are powerful tools for studying hypernuclear physics.We develop a dynamical coalescence model coupled with an ART model(version1.0) to study the production rates of light nuclear clusters and hype... Heavy-ion collisions are powerful tools for studying hypernuclear physics.We develop a dynamical coalescence model coupled with an ART model(version1.0) to study the production rates of light nuclear clusters and hypernuclei in heavy-ion reactions,for instance,the deuteron(d),triton(t),helium(~3He),and hypertriton(_A^3H)in minimum bias(0-80%centrality)~6Li+^(12)C reactions at beam energy of 3.5A GeV.The penalty factor for light clusters is extracted from the yields,and the distributions of 0 angle of particles,which provide direct suggesetions about the location of particle detectors in the near future facility-High Intensity heavy-ion Accelerator Facility(HIAF) are investigated.Our calculation demonstrates that HIAF is suitable for studying hypernuclear physics. 展开更多
关键词 HEAVY-ION accelerator FACILITY HYPERON HYPERNUCLEI COALESCENCE Light NUCLEI
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High-intensity focused ultrasound ablation:An effective bridging therapy for hepatocellular carcinoma patients 被引量:23
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作者 Tan To Cheung Sheung Tat Fan +11 位作者 See Ching Chan Kenneth SH Chok Ferdinand SK Chu Caroline R Jenkins Regina CL Lo James YY Fung Albert CY Chan William W Sharr Simon HY Tsang Wing Chiu Dai Ronnie TP Poon Chung Mau Lo 《World Journal of Gastroenterology》 SCIE CAS 2013年第20期3083-3089,共7页
AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC pa... AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC patients were listed for liver transplantation(UCSF criteria).The median waiting time for transplantation was 9.5 mo.Twenty-nine patients received transarterial chemoembolization(TACE) as a bringing therapy and 16 patients received no treatment before transplantation.Five patients received HIFU ablation as a bridging therapy.Another five patients with the same tumor staging(within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison.Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores,tumor size and number,and cause of cirrhosis.RESULTS:The HIFU group and TACE group showed no difference in terms of tumor size and tumor number.One patient in the HIFU group and no patient in the TACE group had gross ascites.The median hospital stay was 1 d(range,1-21 d) in the TACE group and two days(range,1-9 d) in the HIFU group(P < 0.000).No HIFU-related complication occurred.In the HIFU group,nine patients(90%) had complete response and one patient(10%) had partial response to the treatment.In the TACE group,only one patient(3%) had response to the treatment while 14 patients(48%) had stable disease and 14 patients(48%) had progressive disease(P = 0.00).Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list(P = 0.559).CONCLUSION:HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis.It may reduce the drop-out rate of liver transplant candidate. 展开更多
关键词 Ablation BRIDGING therapy CIRRHOSIS HEPATOCELLULAR CARCINOMA high-intensity FOCUSED ultrasound Liver TRANSPLANT New technology
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High-intensity focused ultrasound treatment for patients with unresectable pancreatic cancer 被引量:20
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作者 Peng-Zhou Li Shai-Hong Zhu +5 位作者 Wei He Li-Yong Zhu Sheng-Ping Liu Yan Liu Guo-Hui Wang Fei Ye 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第6期655-660,共6页
BACKGROUND:High-intensity focused ultrasound(HIFU)is a non-invasive method of solid tissue ablation therapy.However,only a few studies have reported the effect of HIFU for unresectable pancreatic cancer.This study aim... BACKGROUND:High-intensity focused ultrasound(HIFU)is a non-invasive method of solid tissue ablation therapy.However,only a few studies have reported the effect of HIFU for unresectable pancreatic cancer.This study aimed to evaluate the clinical benefits,survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer.METHODS:Twenty-five patients with unresectable pancreatic cancer were enrolled in our study.All patients received HIFU therapy for tumors at least once.The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status(KPS)scores,pain relief,serum CA19-9,and imaging by B-US and CT before and after the therapy.We also recorded median overall survival time and complications caused by the treatment.RESULTS:In the 25 patients,KPS scores were above 60,and increased KPS was observed in 23 patients after treatment.Pain relief occurred in 23 patients.Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients.B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9.Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment.The median overall survival time was 10 months,and the 1-year survival rate was 42%.No severe complications were observed after HIFU treatment.CONCLUSION:HIFU can effectively relieve pain,increase KPS,decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer. 展开更多
关键词 pancreatic cancer high-intensity focused ultrasound THERAPY
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Investigation of production of medical ^(82)Sr and ^(68)Ge for ^(82)Sr/^(82)Rb and ^(68)Ge/^(68)Ga generators via proton accelerator 被引量:3
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作者 Ozan Artun 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第10期137-147,共11页
How to operate^(82)Sr/^(82)Rb and ^(68)Ge/^(68)Ga generators used in the positron emission tomography scan process is explained, and the importance of ^(82)Sr and ^(68)Ge radionuclides for these generators is revealed... How to operate^(82)Sr/^(82)Rb and ^(68)Ge/^(68)Ga generators used in the positron emission tomography scan process is explained, and the importance of ^(82)Sr and ^(68)Ge radionuclides for these generators is revealed. To produce medical ^(82)Sr and ^(68)Ge by means of a proton accelerator in an irradiation time of 24 h, a proton beam current of250 l A, and an energy range E_(proton)= 100 →5 MeV, the cross sections and the neutron emission spectrum curves of(p,xn) reaction processes on Rb-85, Ga-69 and Ga-71 targets were calculated, and the activities and yields of the product were simulated for the reaction processes. Additionally, the integral yields of the reaction processes were determined via the calculated cross-sectional curves and the mass stopping power obtained from the X-PMSP program. Furthermore, based on the obtained results, the appropriate reaction processes for the production of ^(82)Sr and ^(68)Ge isotopes on Rb-85, Ga-69, and Ga-71 targets are discussed. 展开更多
关键词 RADIOISOTOPE PRODUCTION PROTON accelerator PET RADIOISOTOPE generators
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Safety trial of high-intensity focused ultrasound therapy for pancreatic cancer 被引量:13
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作者 Atsushi Sofuni Fuminori Moriyasu +13 位作者 Takatomo Sano Fumihide Itokawa Takayoshi Tsuchiya Toshio Kurihara Kentaro Ishii Syujiro Tsuji Nobuhito Ikeuchi Reina Tanaka Junko Umeda Ryosuke Tonozuka Mitsuyoshi Honjo Shuntaro Mukai Mitsuru Fujita Takao Itoi 《World Journal of Gastroenterology》 SCIE CAS 2014年第28期9570-9577,共8页
AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)wi... AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC. 展开更多
关键词 high-intensity focused ultrasound Pancreatic cancer Safety trial Tumor ablation ULTRASONOGRAPHY
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