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Construction of Even-Variable 2-Output Almost Optimal Five-Valued Spectra Boolean Functions
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作者 SONG Chao-Fan JI Yan-Han SUN Yu-Juan 《密码学报(中英文)》 北大核心 2025年第3期714-728,共15页
Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively ... Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively studied over the past few decades,there has been limited research on the construction of almost optimal five-valued spectra vectorial Boolean functions.In this paper,we present a construction method for even-variable 2-output almost optimal five-valued spectra balanced Boolean functions,whose Walsh spectra values belong to the set{0,±2^(n/2),±2^(n/2+1)},at the same time,we discuss the existence of sufficient conditions in the construction.Additionally,this paper presents a novel construction method for balanced single-output Boolean functions with even variables featuring a special five-valued spectral structure,whose Walsh spectra values are constrained to the set{0,±2^(n/2),±3·2^(n/2)}.These functions provide new canonical examples for the study of Boolean function spectral theory. 展开更多
关键词 Boolean function Walsh transform semi-bent function five-valued function totally disjoint spectra functions
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Public-Key Function-Private Inner-Product Predicate Encryption from Pairings
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作者 WAN Ming WANG Geng GU Da-Wu 《密码学报(中英文)》 北大核心 2025年第1期227-246,共20页
This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals noth... This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals nothing about the predicate f,as long as f is drawn from an evasive distribution with sufficient entropy.The proposed scheme extends the group-based public-key function-private predicate encryption(FP-PE)for“small superset predicates”proposed by Bartusek et al.(Asiacrypt 19),to the setting of inner-product predicates.This is the first construction of public-key FP-PE with enhanced function privacy security beyond the equality predicates,which is previously proposed by Boneh et al.(CRYPTO 13).The proposed construction relies on bilinear groups,and the security is proved in the generic bilinear group model. 展开更多
关键词 predicate encryption function privacy inner product generic group model
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Tuning surface functional groups and crystallinity in activated carbon for high-voltage lithium-ion capacitors
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作者 AN Ya-bin SUN Yu +5 位作者 ZHANG Ke-liang LI Chen SUN Xian-zhong WANG Kai ZHANG Xiong MA Yan-wei 《新型炭材料(中英文)》 北大核心 2025年第5期1085-1097,I0019-I0021,共16页
Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operati... Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs. 展开更多
关键词 Activated carbon Lithium-ion capacitors Surface functional groups Microcrystalline domains High-voltage cathod
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A series of iridium(Ⅲ)complexes with fluorophenyl isoquinoline ligand and low-efficiency roll-off properties:A density functional theory study
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作者 QIN Zhengkun PAN Zicong +2 位作者 TIAN Hui ZHANG Wanyi SONG Mingxing 《无机化学学报》 北大核心 2025年第6期1235-1244,共10页
We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic ligh... We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction. 展开更多
关键词 density functional theory organic light-emitting diodes luminescent materials Ir(Ⅲ)complexes
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rTMS Improves Cognitive Function and Brain Network Connectivity in Patients With Alzheimer’s Disease
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作者 XU Gui-Zhi LIU Lin +4 位作者 GUO Miao-Miao WANG Tian GAO Jiao-Jiao JI Yong WANG Pan 《生物化学与生物物理进展》 北大核心 2025年第8期2131-2145,共15页
Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,n... Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,neural oscillatory dynamics,and brain network reorganization remain unclear.This investigation seeks to systematically evaluate the therapeutic potential of rTMS as a non-invasive neuromodulatory intervention through a multimodal framework integrating clinical assessments,molecular profiling,and neurophysiological monitoring.Methods In this prospective double-blind trial,12 AD patients underwent a 14-day protocol of 20 Hz rTMS,with comprehensive multimodal assessments performed pre-and postintervention.Cognitive functioning was quantified using the mini-mental state examination(MMSE)and Montreal cognitive assessment(MOCA),while daily living capacities and neuropsychiatric profiles were respectively evaluated through the activities of daily living(ADL)scale and combined neuropsychiatric inventory(NPI)-Hamilton depression rating scale(HAMD).Peripheral blood biomarkers,specifically Aβ1-40 and phosphorylated tau(p-tau181),were analyzed to investigate the effects of rTMS on molecular metabolism.Spectral power analysis was employed to investigate rTMS-induced modulations of neural rhythms in AD patients,while brain network analyses incorporating topological properties were conducted to examine stimulus-driven network reorganization.Furthermore,systematic assessment of correlations between cognitive scale scores,blood biomarkers,and network characteristics was performed to elucidate cross-modal therapeutic associations.Results Clinically,MMSE and MOCA scores improved significantly(P<0.05).Biomarker showed that Aβ1-40 level increased(P<0.05),contrasting with p-tau181 reduction.Moreover,the levels of Aβ1-40 were positively correlated with MMSE and MOCA scores.Post-intervention analyses revealed significant modulations in oscillatory power,characterized by pronounced reductions in delta(P<0.05)and theta bands(P<0.05),while concurrent enhancements were observed in alpha,beta,and gamma band activities(all P<0.05).Network analysis revealed frequency-specific reorganization:clustering coefficients were significantly decreased in delta,theta,and alpha bands(P<0.05),while global efficiency improvement was exclusively detected in the delta band(P<0.05).The alpha band demonstrated concurrent increases in average nodal degree(P<0.05)and characteristic path length reduction(P<0.05).Further research findings indicate that the changes in the clinical scale HAMD scores before and after rTMS stimulation are negatively correlated with the changes in the blood biomarkers Aβ1-40 and p-tau181.Additionally,the changes in the clinical scales MMSE and MoCA scores were negatively correlated with the changes in the node degree of the alpha frequency band and negatively correlated with the clustering coefficient of the delta frequency band.However,the changes in MMSE scores are positively correlated with the changes in global efficiency of both the delta and alpha frequency bands.Conclusion 20 Hz rTMS targeting dorsolateral prefrontal cortex(DLPFC)significantly improves cognitive function and enhances the metabolic clearance ofβ-amyloid and tau proteins in AD patients.This neurotherapeutic effect is mechanistically associated with rTMS-mediated frequency-selective neuromodulation,which enhances the connectivity of oscillatory networks through improved neuronal synchronization and optimized topological organization of functional brain networks.These findings not only support the efficacy of rTMS as an adjunctive therapy for AD but also underscore the importance of employing multiple assessment methods—including clinical scales,blood biomarkers,and EEG——in understanding and monitoring the progression of AD.This research provides a significant theoretical foundation and empirical evidence for further exploration of rTMS applications in AD treatment. 展开更多
关键词 transcranial magnetic stimulation Alzheimer’s disease power spectral density ELECTROENCEPHALOGRAM brain functional network
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Functional cartography of heterogeneous combat networks using operational chain-based label propagation algorithm
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作者 CHEN Kebin JIANG Xuping +2 位作者 ZENG Guangjun YANG Wenjing ZHENG Xue 《Journal of Systems Engineering and Electronics》 2025年第5期1202-1215,共14页
To extract and display the significant information of combat systems,this paper introduces the methodology of functional cartography into combat networks and proposes an integrated framework named“functional cartogra... To extract and display the significant information of combat systems,this paper introduces the methodology of functional cartography into combat networks and proposes an integrated framework named“functional cartography of heterogeneous combat networks based on the operational chain”(FCBOC).In this framework,a functional module detection algorithm named operational chain-based label propagation algorithm(OCLPA),which considers the cooperation and interactions among combat entities and can thus naturally tackle network heterogeneity,is proposed to identify the functional modules of the network.Then,the nodes and their modules are classified into different roles according to their properties.A case study shows that FCBOC can provide a simplified description of disorderly information of combat networks and enable us to identify their functional and structural network characteristics.The results provide useful information to help commanders make precise and accurate decisions regarding the protection,disintegration or optimization of combat networks.Three algorithms are also compared with OCLPA to show that FCBOC can most effectively find functional modules with practical meaning. 展开更多
关键词 functional cartography heterogeneous combat network functional module label propagation algorithm operational chain
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Nicotinic Acid Activated Cp_(2)TiCl_(2) for Synergistic Catalysis of C-H Functionalization to Synthesize 2-(N-substituted amino)-1,4-Naphthoquinones
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作者 WANG Yunyun MA Caixia WANG Tao 《分子催化(中英文)》 北大核心 2025年第5期472-482,I0005,共12页
Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strateg... Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle. 展开更多
关键词 C-H functionalization 2-(N-substituted amino)-1 4-naphthoquinone Cp_(2)TiCl_(2) synergistic catalysis
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Energy flow control of nanofluid-based direct absorption solar collectors with functional optical coatings for efficient solar harvesting
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作者 XU Bing ZENG Rui-jing +1 位作者 ZHENG Nian-ben SUN Zhi-qiang 《Journal of Central South University》 2025年第8期3124-3135,共12页
The nanofluid-based direct absorption solar collector(NDASC)ensures that solar radiation passing through the tube wall is directly absorbed by the nanofluid,reducing thermal resistance in the energy transfer process.H... The nanofluid-based direct absorption solar collector(NDASC)ensures that solar radiation passing through the tube wall is directly absorbed by the nanofluid,reducing thermal resistance in the energy transfer process.However,further exploration is required to suppress the outward thermal losses from the nanofluid at high temperatures.Herein,this paper proposes a novel NDASC in which the outer surface of the collector tube is covered with functional coatings and a three-dimensional computational fluid dynamics model is established to study the energy flow distributions on the collector within the temperature range of 400-600 K.When the nanofluid’s absorption coefficient reaches 80 m^(-1),the NDASC shows the optimal thermal performance,and the NDASC with local Sn-In_(2)O_(3) coating achieves a 7.8% improvement in thermal efficiency at 400 K compared to the original NDASC.Furthermore,hybrid coatings with Sn In_(2)O_(3)/WTi-Al_(2)O_(3) are explored,and the optimal coverage angles are determined.The NDASC with such coatings shows a 10.22%-17.9% increase in thermal efficiency compared to the original NDASC and a 7.6%-19.5% increase compared to the traditional surface-type solar collectors,demonstrating the effectiveness of the proposed energy flow control strategy for DASCs. 展开更多
关键词 direct absorption solar collector NANOFLUID functional optical coatings energy flow control
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A new damage constitutive model for rock strain softening based on an improved Logistic function
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作者 GUO Yun-peng LIU Dong-qiao +1 位作者 YANG Sheng-kai LI Jie-yu 《Journal of Central South University》 2025年第8期3070-3094,共25页
This study proposed a new and more flexible S-shaped rock damage evolution model from a phenomenological perspective based on an improved Logistic function to describe the characteristics of the rock strain softening ... This study proposed a new and more flexible S-shaped rock damage evolution model from a phenomenological perspective based on an improved Logistic function to describe the characteristics of the rock strain softening and damage process.Simultaneously,it established a constitutive model capable of describing the entire process of rock pre-peak compaction and post-peak strain softening deformation,considering the nonlinear effects of the initial compaction stage of rocks,combined with damage mechanics theory and effective medium theory.In addition,this research verified the rationality of the constructed damage constitutive model using results from uniaxial and conventional triaxial compression tests on Miluo granite,yellow sandstone,mudstone,and glutenite.The results indicate that based on the improved Logistic function,the theoretical damage model accurately describes the entire evolution of damage characteristics during rock compression deformation,from maintenance through gradual onset,accelerated development to deceleration and termination,in a simple and unified expression.At the same time,the constructed constitutive model can accurately simulate the stress-strain process of different rock types under uniaxial and conventional triaxial compression,and the theoretical model curve closely aligns with experimental data.Compared to existing constitutive models,the proposed model has significant advantages.The damage model parameters a,r and β have clear physical meanings and interact competitively,where the three parameters collectively determine the shape of the theoretical stress−strain curve. 展开更多
关键词 rock mechanics strain softening improved Logistic function S-shaped model damage evolution constitutive model
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Variable reward function-driven strategies for impulsive orbital attack-defense games under multiple constraints and victory conditions
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作者 Liran Zhao Sihan Xu +1 位作者 Qinbo Sun Zhaohui Dang 《Defence Technology(防务技术)》 2025年第9期159-183,共25页
This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breac... This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breach the defender's interception to rendezvous with the target,while the defender seeks to protect the target by blocking or actively pursuing the attacker.Four different maneuvering constraints and five potential game outcomes are incorporated to more accurately model AD game problems and increase complexity,thereby reducing the effectiveness of traditional methods such as differential games and game-tree searches.To address these challenges,this study proposes a multiagent deep reinforcement learning solution with variable reward functions.Two attack strategies,Direct attack(DA)and Bypass attack(BA),are developed for the attacker,each focusing on different mission priorities.Similarly,two defense strategies,Direct interdiction(DI)and Collinear interdiction(CI),are designed for the defender,each optimizing specific defensive actions through tailored reward functions.Each reward function incorporates both process rewards(e.g.,distance and angle)and outcome rewards,derived from physical principles and validated via geometric analysis.Extensive simulations of four strategy confrontations demonstrate average defensive success rates of 75%for DI vs.DA,40%for DI vs.BA,80%for CI vs.DA,and 70%for CI vs.BA.Results indicate that CI outperforms DI for defenders,while BA outperforms DA for attackers.Moreover,defenders achieve their objectives more effectively under identical maneuvering capabilities.Trajectory evolution analyses further illustrate the effectiveness of the proposed variable reward function-driven strategies.These strategies and analyses offer valuable guidance for practical orbital defense scenarios and lay a foundation for future multi-agent game research. 展开更多
关键词 Orbital attack-defense game Impulsive maneuver Multi-agent deep reinforcement learning Reward function design
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Generalized multiple-mode prolate spheroidal wave functions multi-carrier waveform with index modulation
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作者 XU Zhichao LU Faping +5 位作者 ZHANG Lifan YANG Dongkai LIU Chuanhui KANG Jiafang AN Qi ZHANG Zhilin 《Journal of Systems Engineering and Electronics》 2025年第2期311-322,共12页
A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The p... A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The proposed method,based on the optimized multi-index modulation, does not limit the number of signals in the first and second constellations and abandons the concept of limiting the number of signals in different constellations. It successfully increases the spectrum efficiency of the system while expanding the number of modulation symbol combinations and the index dimension of PSWFs signals. The proposed method outperforms the PSWFs multi-carrier index modulation method based on optimized multiple indexes in terms of spectrum efficiency, but at the expense of system computational complexity and bit error performance. For example, with n=10 subcarriers and a bit error rate of 1×10^(-5),spectral efficiency can be raised by roughly 12.4%. 展开更多
关键词 prolate spherical wave function(PSWF) generalized multiple-mode index modulation spectral efficiency.
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A diagnosis method based on graph neural networks embedded with multirelationships of intrinsic mode functions for multiple mechanical faults
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作者 Bin Wang Manyi Wang +3 位作者 Yadong Xu Liangkuan Wang Shiyu Chen Xuanshi Chen 《Defence Technology(防务技术)》 2025年第8期364-373,共10页
Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types o... Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types of signals or faults in individual mechanical components while being constrained by data types and inherent characteristics.To address the limitations of existing methods,we propose a fault diagnosis method based on graph neural networks(GNNs)embedded with multirelationships of intrinsic mode functions(MIMF).The approach introduces a novel graph topological structure constructed from the features of intrinsic mode functions(IMFs)of monitored signals and their multirelationships.Additionally,a graph-level based fault diagnosis network model is designed to enhance feature learning capabilities for graph samples and enable flexible application across diverse signal sources and devices.Experimental validation with datasets including independent vibration signals for gear fault detection,mixed vibration signals for concurrent gear and bearing faults,and pressure signals for hydraulic cylinder leakage characterization demonstrates the model's adaptability and superior diagnostic accuracy across various types of signals and mechanical systems. 展开更多
关键词 Fault diagnosis Graph neural networks Graph topological structure Intrinsic mode functions Feature learning
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High-thermal free vibration analysis of functionally graded microplates using a new finite element formulation based on TSDT and MSCT
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作者 Huu Trong Dang Nhan Thinh Hoang +2 位作者 Quoc Hoa Pham Trung Thanh Tran Huy Gia Luong 《Defence Technology(防务技术)》 2025年第2期131-149,共19页
Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis r... Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis remain significant challenges.This research aims to develop an effective computational method for analyzing the free vibration of functionally graded(FG)microplates under high temperatures while resting on a Pasternak foundation(PF).This formulation leverages a new thirdorder shear deformation theory(new TSDT)for improved accuracy without requiring shear correction factors.Additionally,the modified couple stress theory(MCST)is incorporated to account for sizedependent effects in microplates.The PF is characterized by two parameters including spring stiffness(k_(w))and shear layer stiffness(k_(s)).To validate the proposed method,the results obtained are compared with those of the existing literature.Furthermore,numerical examples explore the influence of various factors on the high-temperature free vibration of FG microplates.These factors include the length scale parameter(l),geometric dimensions,material properties,and the presence of the elastic foundation.The findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the results of this research will have great potential in military and defense applications such as components of submarines,fighter aircraft,and missiles. 展开更多
关键词 Microplates functionally graded material Finite element method Modified couple stress theory New TSDT High-thermal free vibration Pasternak foundation
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An isogeometric approach for vibration characteristics analysis of functionally graded triply periodic minimal sandwich curved-doubly shell integrated with magneto-electro surface layers subjected to lowvelocity impact load
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作者 Le Hoai Pham Hoang Tu +1 位作者 Van Ke Tran Nguyen Thi Hue 《Defence Technology(防务技术)》 2025年第8期101-125,共25页
In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-ele... In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-electric surface layers(referred to as"FG-TPMS-MEE curved-doubly shells")subjected to low-velocity impact loads.This study presents low-velocity impact load model based on a single springmass(S-M)approach.The FG-TPMS-MEE curved-doubly shells are covered with two magneto-electric surface layers,while the core layer consists of three types:I-graph and Wrapped Package-graph(IWP),Gyroid(G),and Primitive(P),with various graded functions.These types are notable for their exceptional stiffness-to-weight ratios,enabling a wide range of potential applications.The Maxwell equations and electromagnetic boundary conditions are applied to compute the change in electric potentials and magnetic potentials.The equilibrium equations of the shell are derived from a refined higher-order shear deformation theory(HSDT),and the transient responses of the FG-TPMS-MEE curveddoubly shells are subsequently determined using Newmark's direct integration method.These results have applications in structural vibration control and the analysis of structures subjected to impact or explosive loads.Furthermore,this study provides a theoretical prediction of the low-velocity impact load and magneto-electric-elastic effects on the free vibration and transient response of FG-TPMS-MEE curved-doubly shells. 展开更多
关键词 IGA approach Free vibration and transient response Magneto-electro-elastic curved-doubly shell Low-velocity impact load functionally graded triply periodic minimal
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Aerial-ground collaborative delivery route planning with UAV energy function and multi-delivery
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作者 GUO Jingfeng SONG Rui HE Shiwei 《Journal of Systems Engineering and Electronics》 2025年第2期446-461,共16页
With the rapid development of low-altitude economy and unmanned aerial vehicles (UAVs) deployment technology, aerial-ground collaborative delivery (AGCD) is emerging as a novel mode of last-mile delivery, where the ve... With the rapid development of low-altitude economy and unmanned aerial vehicles (UAVs) deployment technology, aerial-ground collaborative delivery (AGCD) is emerging as a novel mode of last-mile delivery, where the vehicle and its onboard UAVs are utilized efficiently. Vehicles not only provide delivery services to customers but also function as mobile ware-houses and launch/recovery platforms for UAVs. This paper addresses the vehicle routing problem with UAVs considering time window and UAV multi-delivery (VRPU-TW&MD). A mixed integer linear programming (MILP) model is developed to mini-mize delivery costs while incorporating constraints related to UAV energy consumption. Subsequently, a micro-evolution aug-mented large neighborhood search (MEALNS) algorithm incor-porating adaptive large neighborhood search (ALNS) and micro-evolution mechanism is proposed. Numerical experiments demonstrate the effectiveness of both the model and algorithm in solving the VRPU-TW&MD. The impact of key parameters on delivery performance is explored by sensitivity analysis. 展开更多
关键词 aerial-ground collaborative delivery(AGCD) route planning unmanned aerial vehicle(UAV)energy function UAV multi-delivery micro-evolution adaptive large neighborhood search.
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Vehicle and onboard UAV collaborative delivery route planning:considering energy function with wind and payload
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作者 GUO Jingfeng SONG Rui HE Shiwei 《Journal of Systems Engineering and Electronics》 2025年第1期194-208,共15页
The rapid evolution of unmanned aerial vehicle(UAV)technology and autonomous capabilities has positioned UAV as promising last-mile delivery means.Vehicle and onboard UAV collaborative delivery is introduced as a nove... The rapid evolution of unmanned aerial vehicle(UAV)technology and autonomous capabilities has positioned UAV as promising last-mile delivery means.Vehicle and onboard UAV collaborative delivery is introduced as a novel delivery mode.Spatiotemporal collaboration,along with energy consumption with payload and wind conditions play important roles in delivery route planning.This paper introduces the traveling salesman problem with time window and onboard UAV(TSPTWOUAV)and emphasizes the consideration of real-world scenarios,focusing on time collaboration and energy consumption with wind and payload.To address this,a mixed integer linear programming(MILP)model is formulated to minimize the energy consumption costs of vehicle and UAV.Furthermore,an adaptive large neighborhood search(ALNS)algorithm is applied to identify high-quality solutions efficiently.The effectiveness of the proposed model and algorithm is validated through numerical tests on real geographic instances and sensitivity analysis of key parameters is conducted. 展开更多
关键词 vehicle and onboard unmanned aerial vehicle(UAV)collaborative delivery energy consumption function route planning mixed integer linear programming model adaptive large neighborhood search(ALNS)algorithm
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基于GWO-RBF神经网络的城市机动车能耗预测
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作者 李四洋 张瑞 +2 位作者 李雅男 陈贺鹏 陈艳艳 《科学技术与工程》 北大核心 2025年第8期3480-3486,共7页
在交通碳达峰和碳中和的背景下,高精度、细粒度、可实施性强的机动车能耗实时预测方法成为交通减碳关键组成之一。针对传统基于回归的车辆能耗模型普适性较差的问题,提出了一种基于径向基函数神经网络(radial basis function neural net... 在交通碳达峰和碳中和的背景下,高精度、细粒度、可实施性强的机动车能耗实时预测方法成为交通减碳关键组成之一。针对传统基于回归的车辆能耗模型普适性较差的问题,提出了一种基于径向基函数神经网络(radial basis function neural network,RBFNN)的车辆能耗预测模型。首先分析车辆能耗影响因素并基于Min-Max标准化方法对影响因素矩阵进行归一化处理,然后基于灰狼算法(grey wolf optimization,GWO)优化RBFNN算法隐藏层中心点、高斯函数的宽度和隐含层与输出层连接的权值的训练,最后从横向模型对比和实车实测数据进行模型预测准确度分析。测试结果表明:RBFNN算法预测准确度较传统回归模型提高约12%,整体准确度达到90%以上,能够很好地对城市机动车能耗进行预测。 展开更多
关键词 机动车 能耗 径向基函数神经网络(RBFNN) 灰狼算法(GWO)
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基于PSO-RBFNN的舰船光纤通信流量预测
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作者 储蓄蓄 洪东 《舰船科学技术》 北大核心 2025年第20期190-194,共5页
为及时捕捉通信流量的变化,提出基于粒子群优化算法-径向基函数神经网络(Particle Swarm Optimization-Radial Basis Function Neural Network,PSO-RBFNN)的舰船光纤通信流量预测方法。以舰船光纤通信网络结构为基础,分析舰船光纤通信... 为及时捕捉通信流量的变化,提出基于粒子群优化算法-径向基函数神经网络(Particle Swarm Optimization-Radial Basis Function Neural Network,PSO-RBFNN)的舰船光纤通信流量预测方法。以舰船光纤通信网络结构为基础,分析舰船光纤通信流量特性,确定动态冲击性、多周期叠加特性和时空相关性为通信流量特征;利用径向基函数神经网络,在舰船光纤通信网络结构的历史流量数据内,提取动态冲击性、多周期叠加特性和时空相关性特征,建立光纤通信流量预测模型;通过粒子群优化算法,优化预测模型参数,确保该模型能够及时捕捉通信流量的变化,输出高精度的舰船光纤通信流量预测结果。实验证明:该方法可有效提取舰船光纤通信流量特征,实现通信流量预测;在不同舰船航行环境下,该方法流量预测的均等系数均高于0.90,即预测精度较高。 展开更多
关键词 粒子群 径向基函数 神经网络 舰船光纤通信 动态冲击性
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基于PSO-RBFNN的船舶横摇运动实时预报
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作者 廖声浩 王立军 +3 位作者 王思思 贾宝柱 尹建川 李荣辉 《广东海洋大学学报》 北大核心 2025年第2期103-108,共6页
【目的】针对船舶横摇运动具有非线性和多变量耦合等特征,提出一种基于粒子群优化(PSO)径向基函数神经网络(RBFNN)的预报模型,以提升预报精度,支持智能航行。【方法】构建基于PSO和RBFNN的混合预报方案。采用PSO对RBFNN的中心和宽度参... 【目的】针对船舶横摇运动具有非线性和多变量耦合等特征,提出一种基于粒子群优化(PSO)径向基函数神经网络(RBFNN)的预报模型,以提升预报精度,支持智能航行。【方法】构建基于PSO和RBFNN的混合预报方案。采用PSO对RBFNN的中心和宽度参数进行全局优化,通过PSO-RBFNN模型对船舶横摇运动进行预报。【结果】基于“育鲲”轮实测和仿真数据,验证了模型的可行性和有效性。仿真结果表明,PSO-RBFNN在3种不同工况下均表现出优异的预报性能[提前3 s预报时,平均绝对误差(MAE)≤0.1119,均方误差(MSE)≤0.0280,均方根误差(RMSE)≤0.1673,归一化均方根误差(NRMSE)≤0.0212,平均绝对百分比误差(MAPE)≤22.9%,决定系数(R^(2))≥0.9884],显著优于PSO-RNN、PSO-BP和PSO-MLP等模型。【结论】PSO-RBFNN模型能够高效、准确地预报船舶横摇运动,并在多种工况下保持稳定的性能优势,为智能航行提供实时可靠的技术支撑。 展开更多
关键词 船舶横摇运动 运动预报 智能航行 径向基函数神经网络 粒子群优化算法
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基于GWO-RBF神经网络的车用燃料电池剩余使用寿命预测 被引量:1
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作者 王文 张晗 +3 位作者 张擘 李斌 杨继斌 王乐 《科学技术与工程》 北大核心 2025年第14期5897-5904,共8页
为研究车用质子交换膜燃料电池的预测和健康管理问题,提出了一种以相对功率损耗率为健康指标、灰狼优化(grey wolf optimizer,GWO)算法与径向基(radial basis function,RBF)神经网络相结合的方法(GWO-RBF),对车用质子交换膜燃料电池的... 为研究车用质子交换膜燃料电池的预测和健康管理问题,提出了一种以相对功率损耗率为健康指标、灰狼优化(grey wolf optimizer,GWO)算法与径向基(radial basis function,RBF)神经网络相结合的方法(GWO-RBF),对车用质子交换膜燃料电池的剩余使用寿命进行预测。首先,通过对初始时刻燃料电池极化曲线的分析,构建以相对功率损耗率为健康指标的计算方法,并采用灰色关联度分析方法验证其可行性。然后,应用GWO算法优化的RBF神经网络预测车用质子交换膜燃料电池的剩余使用寿命。最后,采用两组数据集对提出的方法进行了验证分析。结果表明:与其他方法相比,提出的基于GWO-RBF方法的平均绝对百分比误差、均方根误差最小,决定系数最大,相对误差小于1%。可见本文方法能够以较少的数据集、较高的精度预测车用质子交换膜燃料电池的剩余使用寿命。 展开更多
关键词 燃料电池 寿命预测 相对功率损耗率 灰狼优化算法 径向基神经网络
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