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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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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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联合单颗粒质谱与Score-CAM算法判定分析萎缩芽孢杆菌营养细胞和芽孢
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作者 陈红 张宁 +2 位作者 杜耀华 詹晓波 程智 《质谱学报》 北大核心 2025年第2期175-186,I0002,共13页
萎缩芽孢杆菌(ATCC-9372)是一株重要的芽孢杆菌属菌株,利用单颗粒质谱技术区分萎缩芽孢杆菌营养细胞和芽孢的独特生化标志物,对理解其生物学特性和代谢途径具有重要意义。近年来,国内外单颗粒质谱技术取得了很大进展,但是,随着质谱数据... 萎缩芽孢杆菌(ATCC-9372)是一株重要的芽孢杆菌属菌株,利用单颗粒质谱技术区分萎缩芽孢杆菌营养细胞和芽孢的独特生化标志物,对理解其生物学特性和代谢途径具有重要意义。近年来,国内外单颗粒质谱技术取得了很大进展,但是,随着质谱数据处理算法的不断丰富,还未见联合先进的深度学习算法与单颗粒质谱技术区分不同状态萎缩芽孢杆菌的报道。本研究利用深度学习算法和分类模型可视化方法区分萎缩芽孢杆菌的营养细胞和芽孢,并从粒径和质谱离子特征角度进行分析。通过对比粒径发现,营养细胞的粒径大于芽孢,不同采样时间点的营养细胞的粒径大小基本一致。另外,采用相同的方法建立用于训练及测试分类模型的数据集和用于评价模型分类稳定性的验证集,发现模型在测试集和验证集上的识别准确率均在99%以上;对Score-CAM结果中得分高的特征离子进行成分溯源分析,通过箱型图展现了这些特征离子信号强度的分布差异。本研究从生化角度对不同状态下的萎缩芽孢杆菌进行深入分析,可为质谱数据的处理分析提供思路和方法。 展开更多
关键词 单颗粒质谱 萎缩芽孢杆菌 营养细胞 芽孢 1D-CNN score-CAM
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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Z-Score动态压缩的高效联邦学习算法 被引量:2
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作者 刘乔寿 皮胜文 原炜锡 《计算机应用研究》 CSCD 北大核心 2024年第7期2093-2097,共5页
联邦学习作为一种具有隐私保护的新兴分布式计算范式,在一定程度上保护了用户隐私和数据安全。然而,由于联邦学习系统中客户端与服务器需要频繁地交换模型参数,造成了较大的通信开销。在带宽有限的无线通信场景中,这成为了限制联邦学习... 联邦学习作为一种具有隐私保护的新兴分布式计算范式,在一定程度上保护了用户隐私和数据安全。然而,由于联邦学习系统中客户端与服务器需要频繁地交换模型参数,造成了较大的通信开销。在带宽有限的无线通信场景中,这成为了限制联邦学习发展的主要瓶颈。针对这一问题,提出了一种基于Z-Score的动态稀疏压缩算法。通过引入Z-Score,对局部模型更新进行离群点检测,将重要的更新值视为离群点,从而将其挑选出来。在不需要复杂的排序算法以及原始模型更新的先验知识的情况下,实现模型更新的稀疏化。同时随着通信轮次的增加,根据全局模型的损失值动态地调整稀疏率,从而在保证模型精度的前提下最大程度地减少总通信量。通过实验证明,在I.I.D.数据场景下,该算法与联邦平均(FedAvg)算法相比可以降低95%的通信量,精度损失仅仅为1.6%,与FTTQ算法相比可以降低40%~50%的通信量,精度损失仅为1.29%,证明了该方法在保证模型性能的同时显著降低了通信成本。 展开更多
关键词 联邦学习 Z-score 稀疏化 动态稀疏率
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基于F-score和二进制灰狼优化的肿瘤基因选择方法 被引量:3
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作者 穆晓霞 郑李婧 《南京师大学报(自然科学版)》 CAS 北大核心 2024年第1期111-120,共10页
针对肿瘤基因数据维度高、噪声多、冗余性高的现状,结合Spearman相关系数改进F-score算法,在此基础上优化二进制灰狼算法,提出了一种基于改进F-score和二进制灰狼算法的肿瘤基因选择算法.首先,考虑特征之间的相关性,计算每个特征的F-sc... 针对肿瘤基因数据维度高、噪声多、冗余性高的现状,结合Spearman相关系数改进F-score算法,在此基础上优化二进制灰狼算法,提出了一种基于改进F-score和二进制灰狼算法的肿瘤基因选择算法.首先,考虑特征之间的相关性,计算每个特征的F-score值和特征之间的Spearman相关系数的绝对值;然后,计算权重系数得出各个特征的权重值,依据重要性进行排序,选出初选特征子集;最后,通过收敛因子的衰减曲线和初始化方法优化二进制灰狼算法,调整全局搜索和局部搜索所占比例,增强全局搜索能力并提高局部搜索速度,有效节省时间开销,提升特征选择的分类性能和效率,得到最优特征子集.在9个肿瘤基因数据集上测试所提算法,在分类准确率和筛选特征数目两个指标上进行仿真实验,并与4种其他算法进行对比,实验结果证明所提算法表现良好,可有效降低基因数据维度,并具有较好的分类精度. 展开更多
关键词 肿瘤基因 Fisher-score Spearman 相关系数 二进制灰狼优化算法 特征选择
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The correlative analysis of myocardial strain and torsion and quantitative heart function scores in patients with coronary heart disease after PTCA
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作者 Caifen Ye Liangyu Wang +1 位作者 Xiaodong Guo Meng Zhang 《中国循环杂志》 CSCD 北大核心 2018年第S01期160-161,共2页
Objective To assess the relationship of myocardial strain and torsion and quantitative heart function scores in patients with coronary heart disease after PTCA.Methods A total of 90 patients with coronary artery disea... Objective To assess the relationship of myocardial strain and torsion and quantitative heart function scores in patients with coronary heart disease after PTCA.Methods A total of 90 patients with coronary artery disease after PTCA were randomly divided into clinically normal heart function group(group A,n=43)and abnormal heart function group(group B,n=47),and 30 healthy people matched with age and gender as the control group(group C,n=30). 展开更多
关键词 MYOCARDIAL strain TORSION QUANTITATIVE heart function scoreS PTCA
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基于中心偏移的Fisher score与直觉邻域模糊熵的多标记特征选择 被引量:1
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作者 孙林 马天娇 《计算机科学》 CSCD 北大核心 2024年第7期96-107,共12页
现有多标记Fisher score模型中边缘样本会影响算法分类效果。鉴于邻域直觉模糊熵处理不确定信息时具有更强的表达能力与分辨能力的优势,文中提出了一种基于中心偏移的Fisher score与邻域直觉模糊熵的多标记特征选择方法。首先,根据标记... 现有多标记Fisher score模型中边缘样本会影响算法分类效果。鉴于邻域直觉模糊熵处理不确定信息时具有更强的表达能力与分辨能力的优势,文中提出了一种基于中心偏移的Fisher score与邻域直觉模糊熵的多标记特征选择方法。首先,根据标记将多标记论域划分为多个样本集,计算样本集的特征均值作为标记下样本的原始中心点,以最远样本的距离乘以距离系数,去除边缘样本集,定义了新的有效样本集,计算中心偏移处理后的标记下每个特征的得分以及标记集的特征得分,进而建立了基于中心偏移的多标记Fisher score模型,预处理多标记数据。然后,引入多标记分类间隔作为自适应模糊邻域半径参数,定义了模糊邻域相似关系和模糊邻域粒,由此构造了多标记模糊邻域粗糙集的上、下近似集;在此基础上提出了多标记邻域粗糙直觉隶属度函数和非隶属度函数,定义了多标记邻域直觉模糊熵。最后,给出了特征的外部和内部重要度的计算公式,设计了基于邻域直觉模糊熵的多标记特征选择算法,筛选出最优特征子集。在多标记K近邻分类器下、9个多标记数据集上的实验结果表明,所提算法选择的最优子集具有良好的分类性能。 展开更多
关键词 多标记学习 特征选择 Fisher score 多标记模糊邻域粗糙集 邻域直觉模糊熵
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