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Parallel divergence with shared barriers,and niche separation between two sympatric avian species groups 认领 引用 被引量：1
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作者 Lei Wu Huan Wang +10 位作者 Yanzhu Ji Ali Haghani Yan Hao Dezhi Zhang Gang Song Yalin Cheng Martin Päckert Jochen Martens Chenxi Jia Per Alström Fumin Lei 《Journal of Systematics and Evolution》 SCIE CSCD 2026年第1期77-94,共18页
Geographic barriers and geological historical events may play pivotal roles in driving allopatric divergence among closely related species.Here,we investigate the genomic divergence patterns and ecological niche separ... Geographic barriers and geological historical events may play pivotal roles in driving allopatric divergence among closely related species.Here,we investigate the genomic divergence patterns and ecological niche separation of the Willow Tit Poecile montanus and the Marsh Tit P.palustris species groups in China,and their ecological niche separation across East Asia.Through comprehensive genomic sequencing,population genomic analysis,and integration of public occurrence data,we unveil striking parallels in the geographic divergence patterns between these two species groups.Notably,both species exhibit multiple divergent lineages in China,with similar spatial distributions of geneflow barriers.Furthermore,our analysis reveals unique evolutionary histories in the southwestern clades of both species groups,highlighting the intricate interplay between historical distribution dynamics,ecological preferences,and genetic divergence.Our study significantly enhances our understanding of the processes underlying the diversification of closely related widespread species within the framework of shared geographical constraints,and stresses the need for a taxonomic revision. 展开更多
关键词 biogeography East Asia Marsh Tit parallel divergence Willow Tit
FTCSEM—A FORTRAN-based parallelized 1D CSEM forward and inversion program for arbitrary source-receiver geometry 认领 引用
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作者 Wei-ying Chen Si-xu Han +2 位作者 Wan-ting Song Yu-lian Zhu Zheng Liu 《Applied Geophysics》 SCIE CSCD 2026年第2期693-709,870,共17页
This study introduces FTCSEM,a FORTRAN-based,parallelized one-dimensional controlledsource electromagnetic(CSEM)forward modeling and inversion software capable of accommodating arbitrary source-receiver confi guration... This study introduces FTCSEM,a FORTRAN-based,parallelized one-dimensional controlledsource electromagnetic(CSEM)forward modeling and inversion software capable of accommodating arbitrary source-receiver confi gurations.In comparison to existing one-dimensional CSEM tools,FTCSEM incorporates several signifi cant enhancements:it supports transmitters of diverse shapes,quantities,and spatial locations;permits receivers to be positioned flexibly on the surface,subsurface,or in the atmosphere;facilitates simulations and inversions in both frequency and time domains;integrates an adaptive regularized inversion algorithm with multiple model constraints;and leverages GPU-accelerated parallel computing to attain high computational efficiency.Validation through numerical experiments and field data inversion confirms the program’s accuracy and practical applicability.The findings indicate that FTCSEM performs robustly in complex geoelectric environments,multi-source and multi-receiver arrangements,as well as multi-component joint inversion scenarios,thereby offering a versatile and powerful tool for advancing CSEM research and applications. 展开更多
关键词 CSEM forward modeling regularized inversion parallel computing program
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Optimal design of a novel dual-axis parallel solar tracker 认领 引用
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作者 Bin Zhu Liping Wang +2 位作者 Jun Wu Hengchun Cui Yanling Tian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第2期167-179,共13页
Being renewable and readily available,solar energy has gained significant attention in addressing the global energy crisis and climate change.The efficiency of solar-energy harvesting using a concentrator depends on t... Being renewable and readily available,solar energy has gained significant attention in addressing the global energy crisis and climate change.The efficiency of solar-energy harvesting using a concentrator depends on the angle between the incident sunlight and the solar concentrator.Therefore,a solar-energy collection system equipped with a solar tracker that follows the apparent motion of the sun offers the highest collection efficiency.In this study,a novel solar tracker with a parallel mechanism is proposed based on the line graph method.The proposed parallel solar tracker(PST) features a main column with passive movements and two UPU chains that share a common constraint.This design enhances the rotational workspace,stiffness,and load-bearing capacity of the system.To solve the forward kinematics problem of the PST efficiently and accurately,a geometric elimination method is employed,converting the three-dimensional kinematics into a simpler planar problem.This allows the forward kinematics problem to be solved analytically using planar equations.By considering key performance indices,such as the effective workspace,transmission,and manipulability,the structural parameters of the PST are optimized in two steps,thereby identifying the optimal region in the design space.Finally,the computational efficiency and accuracy of both the forward and inverse kinematic solutions for the PST with optimized structural parameters are validated,demonstrating their potential for use in real-time control systems.The proposed novel solar tracker has high stiffness and load-bearing capacity.The study provides a solid foundation for improving the efficiency of solar energy utilization. 展开更多
关键词 Solar tracker Parallel mechanism Forward kinematics Effective workspace Transmissibility Manipulability
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The three-dimensional meshfree numerical manifold method based on parallel computing 认领 引用
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作者 Keqin Zhang Wei Wu +2 位作者 Danfeng Zhang Yanfei Kang Hehua Zhu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第2期360-371,共12页
The numerical manifold method,extensively utilized in numerical computations,faces significant challenges in generating complex manifold elements,particularly for three-dimensional applications.To overcome this challe... The numerical manifold method,extensively utilized in numerical computations,faces significant challenges in generating complex manifold elements,particularly for three-dimensional applications.To overcome this challenge,the meshfree numerical manifold method is developed by integrating the moving least-squares method into the numerical manifold method,effectively bypassing the need for meshing complex geometric objects.However,the implementation of the moving least-squares method introduces computational efficiency issues.To mitigate these,parallel computing methods have been incorporated,resulting in a tenfold increase in the speed of assembling the stiffness matrix with central processing unit parallelism,and a twentyfold increase with graphics processing unit parallelism.The static mechanical system equations for the meshfree numerical manifold method are derived using the Galerkin method.The method’s effectiveness and accuracy are then validated through a series of numerical experiments.The experiments demonstrated that the meshfree numerical manifold method achieves a high precision with minimal nodes and integration points.Additionally,positioning nodes outside the domain significantly improves computational accuracy at the boundaries. 展开更多
关键词 Meshfree numerical manifold method Three-dimensional computation Parallel computation Elastostatics Moving least-squares
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Advancements and theoretical foundations of cable-driven parallel robots:A comprehensive overview 认领 引用
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作者 Kamran Joyo Han Yuan +2 位作者 Jun Wu Wenfu Xu Honghao Yue 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第3期280-305,共26页
Parallel robotic mechanisms using cables instead of rigid limbs are termed cable-driven parallel robots(CDPRs).Electric motors and pulley mechanisms actuate cables to provide motion for an end-effector in a cable robo... Parallel robotic mechanisms using cables instead of rigid limbs are termed cable-driven parallel robots(CDPRs).Electric motors and pulley mechanisms actuate cables to provide motion for an end-effector in a cable robot.Consequently,CDPRs have emerged as indispensable tools across a spectrum of industrial and technological domains,including astronomy,aerospace,logistics,simulators,and rehabilitation.Their inherent compatibility with the evolving concept of rigid-flexible fusion places CDPRs at the forefront of cutting-edge robotics research.This comprehensive paper aims to consolidate the core theories and advancements underpinning CDPRs,en-compassing key aspects such as configuration design,cable-force distribution,workspace and stiffness analysis,performance evaluation,optimisation techniques,and motion control.We provide in-depth insights into kine-matic modelling,workspace exploration,and cable-force solutions.Furthermore,the paper delves into the in-tricacies of stiffness and dynamic modelling,presenting a range of analytical methods to elucidate their effects on CDPR performance.Addressing reliability concerns and developing a unified control framework are identified as essential in ensuring the practical deployment of CDPRs in real-world scenarios.This research paper offers a comprehensive overview of the theories and advancements in CDPRs,identifying critical areas for further re-search and development to unlock the full potential of these versatile and high-performance robotic systems. 展开更多
关键词 Cable-driven parallel robots Optimisation Path generation Statics Machine learning
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A high-performance parallel algorithm based on problem independent machine learning(PIML)for large-scale topology optimization 认领 引用
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作者 Xinyu Ma Mengcheng Huang +4 位作者 Zongliang Du Yilin Guo Chang Liu Yue Mei Xu Guo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第3期197-213,共17页
Although supplying extensive design space,the curse of dimensionality restricts the widespread application of largescale topology optimization in practical engineering.Various acceleration techniques have been integra... Although supplying extensive design space,the curse of dimensionality restricts the widespread application of largescale topology optimization in practical engineering.Various acceleration techniques have been integrated with topology optimization,achieving significant attention and progress in large-scale problems.This work aims to investigate how much benefit can be obtained by combining parallel computing and machine learning techniques to enhance the efficiency of large-scale topology optimization algorithms.Accordingly,a parallel problem independent machine learning(PIML)-enhanced topology optimization method is proposed.The PIML model substantially reduces the dimension of the condensed stiffness matrix and its computational cost,and parallel computing reduces the workload per process and enables the application of a parallel multigrid solver.Besides,several techniques,such as matrix-free implementation,direct condensation of uniform coarse elements,and adjusting computational resource limits,have been developed to enhance computational efficiency.The weak scaling efficiency,strong scaling speedup,and maximum achievable efficiency of the proposed method are validated across multiple numerical examples,showing significant improvement in the tractable problem size and solution efficiency compared to traditional topology optimization algorithms. 展开更多
关键词 Topology optimization Large-scale Problem independent machine learning(PIML) Parallel computing
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Stiffness evaluation and experimental test of a novel redundantly actuated parallel machining robot 认领 引用
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作者 Hanliang Fang Jian Wang +2 位作者 Shuyi Ge Fufu Yang Jun Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期413-422,共10页
Parallel machining robot is a new type of robotized equipment for high-efficiency machining structural com-ponents with complex geometries.Terminal rigidity is of great importance index for such type of equipment,whic... Parallel machining robot is a new type of robotized equipment for high-efficiency machining structural com-ponents with complex geometries.Terminal rigidity is of great importance index for such type of equipment,which affects their load capacity and working accuracy.Before a parallel machining robot can be used for heavy-load and high-efficiency machining,its terminal rigidity should be evaluated systematically.The present study is to quantitatively reveal the stiffness properties of a previously invented Z4 redundantly actuated parallel ma-chining robot(RAPMR).For this purpose,two critical issues,i.e.,stiffness modelling and index construction,are clarified to carry out stiffness evaluation of the Z4 RAPMR.Firstly,drawing on the screw theory,a semi-analytic stiffness model of the proposed RAPMR is established at a component level.Secondly,a set of virtual work-based stiffness indices is constructed to evaluate the terminal rigidity of parallel robots.Those indices have a consistent physical unit in describing linear and angular terminal rigidity.With these indices,the local and the global stiffness performance of the Z4 RAPMR are predicted.Thirdly,a laboratory prototype of the proposed RAPMR is fabricated.And the experimental test is performed to verify the correctness of the established stiffness model.The present work is expected to provide fundamental information for further light-weight design and rigidity enhancement. 展开更多
关键词 Parallel machining robot Redundantly actuated Terminal rigidity Stiffness model Experimental test
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Optical properties of soil water-extractable organic matter respond to changes in irrigation water quality 认领 引用
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作者 Mikhail BORISOVER Asher BAR-TAL +3 位作者 Nadezhda BUKHANOVSKY Anna BEREZKIN Marcos LADO Guy J.LEVY 《Pedosphere》 SCIE CAS CSCD 2026年第2期638-654,共17页
Treated wastewater(TWW)irrigation may harm soil and agricultural production.Adverse effects of TWW irrigation may be mitigated by changing irrigation water quality,e.g.,use of fresh water(FW),or management,e.g.,lower-... Treated wastewater(TWW)irrigation may harm soil and agricultural production.Adverse effects of TWW irrigation may be mitigated by changing irrigation water quality,e.g.,use of fresh water(FW),or management,e.g.,lower-frequency irrigation(LFI)with TWW.The influence of mitigation treatments on soil organic matter and water-extractable organic matter is unknown.To examine this influence,a study was conducted in an avocado orchard irrigated from 2009 with secondary TWW.Four parallel treatments were applied for six years(2016-2021),involving irrigation with FW,a 1:1 FW-TWW mixture,TWW at LFI(twice a week),and TWW irrigation three times a week as control.Soil samples from three depths were characterized for total organic and inorganic carbon and nitrogen and using Fourier-transform infrared spectra that were decomposed into components by nonnegative matrix factorization.Aqueous extracts of soil samples were characterized for dissolved organic carbon(DOC),inorganic carbon,and nitrogen concentrations,absorbance at254 nm(Abs254),and excitation-emission matrices of fluorescence that were decomposed into components by parallel factor analysis.The Abs254 and fluorescence of humic-like components in the soil extracts were the attributes most consistently responding to irrigation water quality.Irrigation with FW and a 1:1 FW-TWW mixture led to decreases in the concentrations of aromatic and humic-like constituents in the soil extracts compared with the control TWW irrigation.Changing soil irrigation management had no or little impact on those attributes compared with the control TWW irrigation.Results of the study support the use of optical properties related to the concentrations of ultraviolet-absorbing and light-emitting constituents in soil extracts,rather than the whole DOC concentration,as sensitive descriptors suitable for evaluating soil response in different agricultural scenarios. 展开更多
关键词 fluorescence Fourier-transform infrared spectroscopy humic-like substances nonnegative matrix factorization parallel factor analysis specific ultraviolet absorbance treated wastewater
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Numerical Study of Hydrodynamic and Motion Interference Characteristics of Twin Projectiles Entering Water 认领 引用
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作者 QI Chao ZHAO Jia-zhen +3 位作者 WANG Xu HAN Ke-xin WAN Zong-hao LYU Xu-jian 《China Ocean Engineering》 SCIE EI CSCD 2026年第3期521-534,共14页
The water entry of multiple projectiles generates complex motion interference and cavity coupling between bodies,resulting in intricate flow field structures and motion characteristics.This study presents a computatio... The water entry of multiple projectiles generates complex motion interference and cavity coupling between bodies,resulting in intricate flow field structures and motion characteristics.This study presents a computational fluid dynamics(CFD)approach for simulating the hydrodynamic properties of high-speed vertical water entry by parallel projectiles.The numerical method’s validity is verified through experimental comparisons.The study investigates the interference characteristics of parallel projectiles in terms of axis distance,time interval,and water-entry velocity,and compares these behaviors with those of a single projectile.The numerical results reveal that parallel projectile water entry exhibits more complex characteristics,including cavity coupling,surface wetting,and load variations.At G=1.5,extensive shoulder wetting produces substantial lateral forces and yaw moments,affecting both projectiles’attitudes.This negatively impacts underwater trajectory stability and targeting precision.In supercavitating conditions(G≥6),multi-disturbances become negligible.The wake of the leading projectile generates a non-uniform initial flow field for the trailing projectile,while the entry of the trailing projectile subsequently influences the motion of the leading one.This mutual interaction is most pronounced at small time intervals(Δt=0.2 ms).Notably,water-entry velocity exerts less influence on the hydrodynamic characteristics than axis distance and time interval. 展开更多
关键词 parallel projectiles high-speed water entry hydrodynamic characteristics cavity evolution
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A 32‑channel charge‑sensitive amplifier for delay‑line readout of parallel plate avalanche counter array 认领 引用
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作者 Yue‑Zhao Zhang Peng Ma +8 位作者 Zhuang‑Yu Lin Zhen‑Fei Tan Xing‑Chi Han Chen Liu Shuo Wang Da‑Peng Sun Zhi‑Quan Li En‑Hong Wang Shou‑Yu Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第1期164-179,共16页
A 32-channel charge-sensitive amplifier(CSA)is designed for fast timing in the delay-line readout of a parallel plate avalanche counter(PPAC)array.It is realized on a PCB with operational amplifiers and other discrete... A 32-channel charge-sensitive amplifier(CSA)is designed for fast timing in the delay-line readout of a parallel plate avalanche counter(PPAC)array.It is realized on a PCB with operational amplifiers and other discrete components.Each channel consists of an integrator,a pole-zero cancellation net,and a linear amplification stage,which can be adapted to accommodate either positive or negative input signals.The RMS equivalent input noise charges are 3.3 fC,the conversion gains are approximately±2 mV∕fC,and the intrinsic time resolution reaches 32 ps.In the prototype PPAC application,the CSA performs as well as the commercial FTA820A amplifier,providing a position resolution as good as 0.17 mm,and exhibiting reliable stability during several hours of continuous data acquisition. 展开更多
关键词 Charge-sensitive amplifier Fast timing Parallel plate avalanche counter Delay-line Discrete components
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A High-Fidelity and High-Efficiency Simulator for 6G-Integrated Space-Ground Networks 认领 引用
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作者 Haibo Zhou Xiaoyu Liu +5 位作者 Xin Zhang Xiaohan Qin Mengyang Zhang Yuze Liu Weihua Zhuang Xuemin Shen 《Engineering》 SCIE EI CSCD 2026年第1期62-78,共17页
Mega-constellation networks have recently gained significant research attention because of their potential for providing ubiquitous and high-capacity connectivity in future sixth-generation(6G)wireless communication s... Mega-constellation networks have recently gained significant research attention because of their potential for providing ubiquitous and high-capacity connectivity in future sixth-generation(6G)wireless communication systems.However,the high dynamics of network topology and large scale of a megaconstellation pose new challenges to constellation simulation and performance evaluation.To address these issues,we introduce Ultra Star,a high-fidelity and high-efficiency computer simulator to support the development of 6G wireless communication systems with low-Earth-orbit mega-constellation satellites.The simulator facilitates the design and performance analysis of various algorithms and protocols for network operation and deployment.We propose a systematic,scalable,and comprehensive simulation architecture for the high-fidelity modeling of network configurations and for performing highefficiency simulations of network operations and management capabilities,while providing users with intuitive visualizations.We capture heterogeneous topology characteristics by establishing an environment update algorithm that incorporates real ephemeris data for satellite orbit prediction,sun outages,and link handovers.For a realistic simulation of software and hardware configurations,we develop a Network Simulator 3 based network model to support networking protocol extensions.We propose a message passing interface-based parallel and distributed approach with multiple cores or machines to achieve high simulation efficiency in large and complex network scenarios.Experimental results demonstrate the high fidelity and efficiency of Ultra Star can help pave the way for 6G integrated space-ground networks. 展开更多
关键词 Low-Earth-orbit satellite networks Discrete event simulation architecture Parallel and distributed simulation Performance evaluation
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Constrained RLV guidance via pseudospectral model predictive convex programming and predefined-height sliding mode approach 认领 引用
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作者 Zhe LIU Naigang CUI +1 位作者 Feng ZHANG Jialun PU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期466-482,共17页
Online trajectory generation and tracking for the Terminal Area Energy Management(TAEM)phase of a Reusable Launch Vehicle(RLV)is one of the core technologies for achieving a soft landing.The processing of complex non-... Online trajectory generation and tracking for the Terminal Area Energy Management(TAEM)phase of a Reusable Launch Vehicle(RLV)is one of the core technologies for achieving a soft landing.The processing of complex non-convex path constraints significantly reduces the real-time performance of guidance methods.In addition,the terminal full-element state constraints are difficult to satisfy due to the coupling of longitudinal and lateral motion of RLV.To address these issues,a high-precision constrained guidance method for RLV is proposed in this paper.The analytical sensitivity relationships among the terminal states,non-convex path constraints,and control profile are rapidly constructed via multi-interval pseudospectral discretization.The repeated recursive calculation of sensitivity matrix is avoided by linearizing the non-convex constraints at state output points and expanding the sensitivity matrix sequentially,which reduces the time consumption of constraint processing.Furthermore,a model-based prediction-correction process is introduced to eliminate deviation iteratively and constraints are handled using homotopy to improve convergence.Meanwhile,a robust parallel guidance method is presented to overcome numerical instability issues.The guidance commands obtained by trajectory online generation are prioritized executed,while the tracking commands are calculated in parallel to enhance the guidance feasibility.Instead of tracking a fixed reference trajectory,a predefined height-convergent sliding mode surface is designed and tracked online,which can guarantee that the RLV states converge to the desired values at a preset height,even under various uncertainties.Finally,Monte Carlo simulations are conducted to demonstrate the effectiveness and robustness of the proposed method. 展开更多
关键词 Convex optimization Model predictive Parallel guidance Pseudospectral discretization Reusable launch vehicle
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Multi-beam scanning electron microscope(MBSEM):Technological evolution,core breakthroughs,and cross-field applications 认领 引用
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作者 Wuyang Tan Mengni Liu +5 位作者 Ke Pei Chendi Yang Jiazhuan Qin Chao Wang Xuebing Zhao Renchao Che 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第6期501-512,共12页
Multi-beam scanning electron microscope(MBSEM)reconciles the inherent contradiction between“resolution and throughput”of traditional scanning electron microscopes(SEMs)through parallel electron beam manipulation,eme... Multi-beam scanning electron microscope(MBSEM)reconciles the inherent contradiction between“resolution and throughput”of traditional scanning electron microscopes(SEMs)through parallel electron beam manipulation,emerging as a key technology to address the bottlenecks in large-volume,high-resolution imaging and advanced industrial inspection.This article provides a comprehensive overview of MBSEM,covering its evolutionary course of technology,core design fundamentals,and interdisciplinary applications.First,it sorts out the evolutionary process from conceptualization in the early 21 st century to commercialization in the 2010s,clarifying the core logic of breaking through the physical limitations of single-beam systems via“multi-beam parallelism”.Subsequently,focusing on the core technological chain of“beam generation–optical focusing–signal detection–data processing”,it conducts an in-depth analysis of the design concepts,technical characteristics,and applicable scenarios of three mainstream architectures:the single-source single-column,split optical system,and semiconductor-specific multi-beam inspection(MBI).Combined with representative research and product data from teams such as Delft University of Technology,Zeiss,and ASML/HMI,it reveals the differentiated advantages of each architecture in beam uniformity(the relative deviation percentage of the current density and probe size of each sub-beam in the multi-beam array from the central beam,with a smaller deviation value indicating better uniformity)and signal crosstalk(the percentage of the interference signal intensity to the target signal intensity when the detection signal of a single beam in the multi-beam array interferes with the detection channel of adjacent beams)control,and throughput(the percentage of the interference signal intensity to the target signal intensity when the detection signal of a single beam in the multi-beam array interferes with the detection channel of adjacent beams)improvement.Finally,integrating the practical demands of neuroscience connectomics,advanced semiconductor manufacturing processes,and biomedicine,it elaborates on the application breakthroughs of MBSEM in the three-dimensional(3D)reconstruction of large-volume brain tissue,wafer defect screening for 7 nm and smaller nodes,and low-damage imaging of thin biological tissues,and compares its disruptive value relative to traditional technologies(single-beam SEM,optical inspection).Unlike previous reviews,this work systematically integrates both academic prototypes and industrial systems for the first time,providing an in-depth analysis of the differentiated trade-offs among imaging speed,resolution,and sample adaptability across different architectures,offering a systematic reference for MBSEM R&D and interdisciplinary applications. 展开更多
关键词 multi-beam scanning electron microscopy(MBSEM) parallel imaging technology connectomics advanced semiconductor process inspection beam control and signal processing
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Symmetry Breaking in Parallel 1-K Sorption Coolers and Passive Suppression Strategy 认领 引用
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作者 Lihao Lu Yan Lu +2 位作者 Zhenhua Jiang Shaoshuai Liu Yinong Wu 《Frontiers in Heat and Mass Transfer》 EI CAS 2026年第3期105-122,共18页
Sub-Kelvin cooling technology is a critical prerequisite for high-sensitivity detection in deep space exploration and quantum computing.Operating identical sorption coolers in parallel is a common engineering approach... Sub-Kelvin cooling technology is a critical prerequisite for high-sensitivity detection in deep space exploration and quantum computing.Operating identical sorption coolers in parallel is a common engineering approach to enhance cooling capacity and extend hold time for these cryogenic platforms.However,this study reports an unexpected"symmetry breaking"phenomenon observed in a parallel Helium-4 sorption cooling system where the cold heads are connected via Oxygen-Free High Thermal Conductivity(OFHC)copper linkages.Instead of the expected uniform load sharing,the system spontaneously evolves into an asymmetric"quasi-series"operational mode.In this state,one cooler preferentially consumes its liquid helium inventory while the other remains dormant,significantly reducing system efficiency.To elucidate the underlying physics,a transient thermal-fluidic resistance network model was developed and validated against experimental data obtained from a dual-cooler test rig pre-cooled by a G-M cryocooler.Theoretical analysis reveals that this thermal locking originates from a positive feedback loop driven by the temperature-dependent thermal conductivity of the copper straps.Experimental results further demonstrate that system stability degrades significantly with increasing thermal load,with the synchronization ratio dropping from 75.3%at 0 mW to 51.3%at 3 mW.This indicates that at higher temperatures,the destabilizing gain of the thermal link overwhelms the restoring stiffness of the sorption mechanism.To address this intrinsic instability,a passive suppression strategy using a series"Ballast Thermal Resistance"is proposed.Numerical optimization identifies a critical resistance value of approximately 10 K/W,which effectively dampens the positive feedback and restores the synchronization ratio to over 95%with a negligible thermal penalty of less than 20 mK.These findings provide a theoretical basis and practical design guidelines for the stabilization of multi-cooler cryogenic networks. 展开更多
关键词 Sorption cooler parallel system symmetry breaking thermal locking passive stabilization ballast thermal resistance
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A Deep Reinforcement Learning-Based Partitioning Method for Power System Parallel Restoration 认领 引用
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作者 Changcheng Li Weimeng Chang +1 位作者 Dahai Zhang Jinghan He 《Energy Engineering》 EI 2026年第1期243-264,共22页
Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision... Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training. 展开更多
关键词 Partitioning method parallel restoration deep reinforcement learning experience replay buffer partitioning modularity
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A Competitive Parallel Animated Oat Optimization Algorithm for Reversible Digital Watermarking 认领 引用
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作者 Shu-Chuan Chu Libin Fu Jeng-Shyang Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第7期1209-1238,共30页
The Animated Oat Optimization Algorithm(AOO)is a novel evolutionary algorithm inspired by the behavior of animated oats.This paper proposes a Competitive Parallel Animated Oat Optimization Algorithm(CPAOO)comprising t... The Animated Oat Optimization Algorithm(AOO)is a novel evolutionary algorithm inspired by the behavior of animated oats.This paper proposes a Competitive Parallel Animated Oat Optimization Algorithm(CPAOO)comprising two components.First,a parallel strategy is employed in which inter-subpopulation communication is triggered at predefined iteration thresholds to balance exploration and exploitation.Second,a grouped competition strategy with incentive mechanisms is introduced,enabling the prioritized evolution of superior individuals to enhance the algorithm’s efficiency.Furthermore,building on the Prediction Error Expansion(PEE)algorithm,this paper proposes a Dual-Layer PEE(DLPEE)algorithm for reversible digital watermarking.Based on differences in pixel values around embedding points,image blocks are classified as either smooth or textured regions.The CPAOO algorithm is used to optimize the weights of the pixel predictor and to prioritize embedding secret information in smooth blocks.This approach enhances both the embedding capacity and the invisibility of the watermarked data.Experimental results demonstrate that the proposed methods achieve satisfactory performance. 展开更多
关键词 Evolutionary algorithm parallel strategy communication strategy grouped competition strategy reversible digital watermarking
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露天矿卡平行自主运输系统研究 认领 引用 被引量：2
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作者 郭伦锋 郭一楠 +3 位作者 葛世荣 杨健健 纪佩瑶 王杰 《工矿自动化》 CSCD 北大核心 2026年第3期1-14,143,共14页
露天矿运输系统具有设备多样、作业点分布、作业流程时空耦合、环境动态变化等特性,导致其高效管理与控制存在挑战。此外,极端工况下系统测试困难及特定场景的感知数据不足,使系统性能难以全面评估,导致决策与控制策略对场景的适应性差... 露天矿运输系统具有设备多样、作业点分布、作业流程时空耦合、环境动态变化等特性,导致其高效管理与控制存在挑战。此外,极端工况下系统测试困难及特定场景的感知数据不足,使系统性能难以全面评估,导致决策与控制策略对场景的适应性差,泛化能力弱,运行稳定性与安全性难以保障,从而影响系统整体可靠性。针对上述问题,提出一种基于平行理论与车路云融合控制理念的露天矿平行自主运输系统。该系统由物理系统、工业互联网和人工系统3个部分构成。其中,人工系统采用边缘云、矿山云和中心云三级云控架构,通过云控基础平台与云控应用平台实现多层级协同控制。云控基础平台是云计算中心,可保障各级云控应用对实时性与服务范围的多样化需求。云控应用平台包括资源库及面向生成场景的平行学习与平行协同。资源库由模型库和算法库构成,实现建模方法选取和场景定义,为算法训练与协同控制提供方法支撑。平行学习通过虚实结合的平行训练与平行测试,构建人工系统和实际运输系统之间的数据闭环,从而解决算法数据不足和极端场景测试困难问题,推动系统自演化。平行协同基于三级云控架构与多智能体技术,实现协同感知、态势预测和分层分布式协同控制,有效应对多设备协同管理复杂与实时控制难题。实例分析结果表明,平行训练方法不仅有效减少了数据采集和标注的工作量,同时也显著提高了目标检测模型的精度和鲁棒性。 展开更多
关键词 露天矿 自主运输 平行训练与测试 虚实结合 多智能体 平行学习 平行协同
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一种面向多模态模型的分区混合并行优化方法 认领 引用 被引量：1
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作者 巨涛 丁肖健 +1 位作者 郭东雨 火久元 《西安交通大学学报》 EI CAS CSCD 北大核心 2026年第2期229-240,共12页
针对多模态模型架构复杂、参数量庞大、算力需求高,导致训练难度大、效率低,以及现有数据并行与模型并行策略难以应对内部异构特性的问题,提出了一种面向多模态模型的分区混合并行优化(MMHP)方法。首先根据多模态模型中不同子模块的异构... 针对多模态模型架构复杂、参数量庞大、算力需求高,导致训练难度大、效率低,以及现有数据并行与模型并行策略难以应对内部异构特性的问题,提出了一种面向多模态模型的分区混合并行优化(MMHP)方法。首先根据多模态模型中不同子模块的异构性,构建模块依赖图,识别关键切分点,实现模块分区,保证子模块间的负载均衡;其次,针对不同模块分区的参数规模和计算需求,融合数据并行与模型并行,设计混合并行优化方法以适应异构计算任务的多样化需求;最后,基于动态规划设计计算任务调度优化算法,动态分配计算资源,实现计算任务与资源合理匹配,进一步优化计算资源的利用率,提升模型的训练效率。实验结果表明,在不影响模型训练精度的情况下,所提出的MMHP方法可充分利用计算资源,提升多模态模型的训练效率,与现有主流并行策略相比,训练速度最大可提升2倍。 展开更多
关键词 多模态模型 混合并行 并行优化 模块分区 调度优化
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Investigation on optical sinc-shaped Nyquist pulse generation based on external modulation 认领 引用
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作者 Jin YUAN Xiuxiu XU 《Optoelectronics Letters》 EI 2026年第2期82-86,共5页
In this paper, a scheme for generating sinc-shaped optical Nyquist pulses based on external modulation is proposed. First, five flat optical frequency comb(OFC) lines are generated by a dual-parallel Mach–Zehnder mod... In this paper, a scheme for generating sinc-shaped optical Nyquist pulses based on external modulation is proposed. First, five flat optical frequency comb(OFC) lines are generated by a dual-parallel Mach–Zehnder modulator(DP-MZM) for optical carrier phase cancellation interference. Then, the phase-locked OFC is split into two paths, one of which is transmitted to a single-drive Mach–Zehnder modulator(SD-MZM) for the modulation of the even-order side-band suppression, and the other is used to remodulate the signal in order to obtain equally spaced comb lines. Eventually, equal frequency spaced phase-locked 15-line OFCs are generated and extremely narrow over-zero width Nyquist pulses are realized at 2.5 GHz, 5 GHz, 10 GHz and 20 GHz. The root-mean-square error(RMSE) is calculated for the generated Nyquist pulses which enables the verification of the signal quality. 展开更多
关键词 remodulate s dual parallel Mach Zehnder modulator phase locked optical frequency comb external modulation optical carrier phase cancellation interference flat optical frequency single drive Mach Zehnder modulator optical sinc shaped Nyquist pulses
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煤自燃微观活性结构动态演化与平行反应机制 认领 引用 被引量：4
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作者 王凯 李全芳 +1 位作者 邓军 李鑫 《煤炭学报》 EI CAS CSCD 北大核心 2026年第2期1391-1403,共13页
煤自燃是多步平行反应协同放热并积聚的结果,其放热特性与微观活性结构演化密切相关。为揭示煤自燃多步平行反应路径,采用差示扫描量热、傅里叶原位红外试验与电子顺磁共振试验等手段,测试了变质程度由低到高的4种煤样(SYS、ZJM、YZ、LF... 煤自燃是多步平行反应协同放热并积聚的结果,其放热特性与微观活性结构演化密切相关。为揭示煤自燃多步平行反应路径,采用差示扫描量热、傅里叶原位红外试验与电子顺磁共振试验等手段,测试了变质程度由低到高的4种煤样(SYS、ZJM、YZ、LF)氧化升温过程中官能团与自由基演变特征。结果表明:4种变质程度煤自燃过程均存在脱水脱气、吸附氧气、氧化分解、气相燃烧、固相燃烧等5类平行反应序列,其放热曲线变化及特征温度点偏移与平行反应序列的叠加竞争有关。不同变质程度煤样的活性结构分布差异影响氧化自燃的反应路径,随着变质程度的升高,煤样氧化分解温度降低、燃点温度滞后。不同平行反应序列对煤自燃放热变化的贡献存在差异,脱水脱气与吸附氧气物理反应序列对煤自燃热量变化的贡献率十分微小,在2%左右。氧化分解反应对SYS煤样放热贡献率达67.4%,而气相与固相燃烧反应序列在ZJM、YZ和LF煤样中占据主导地位。ZJM和YZ煤样因放热型反应序列的叠加呈现双放热峰特征,升温速率提高会延迟特征温度但增强了燃烧强度。各阶段官能团与自由基的定性定量分析表明了煤自燃过程中的平行反应类型与协同作用机制。反应初期,羟基和脂肪烃与物理吸附氧反应生成氢过氧化物—OOH,自由基浓度先降后升,煤样热流曲线呈现微小吸热峰;随着温度升高,氧化分解反应占据主导地位,α位带羟基的次乙基键与氧气反应生成醚键,过氧化物大量分解,自由基浓度增长1.8倍左右。其中,中等变质程度的ZJM和YZ煤样因氧化分解反应放热,其热流曲线呈现肩峰。中高温阶段,芳环吸附氧形成的过氧化物前驱体裂解产生羰基,脂肪链断裂促使自由基浓度达到峰值。高温阶段,气相燃烧主导反应,C=O持续呈现高吸光度,芳烃—CH峰面积比衰减60%左右。研究阐明了煤自燃平行反应序列类型及微观活性结构演变规律,明确了平行反应序列的作用路径及煤自燃放热关键官能团。 展开更多
关键词 平行反应 官能团 变质程度 特征温度 自由基
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