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Two Modifications on IKE Protocol with Pre-shared Key Authentication 被引量:3
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作者 刘东喜 张连华 白英彩 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期142-145,共4页
This paper proposed two modifications on IKE protocol with pre-shared key authentication. The first modification can improve its immunity against DDoS attack by authenticating the initiator before the responder genera... This paper proposed two modifications on IKE protocol with pre-shared key authentication. The first modification can improve its immunity against DDoS attack by authenticating the initiator before the responder generates the computation-intensive Diffie-Hellman public value. The second modification can improve its efficiency when the attack on messages occurs because it can detect the attack quickly by replacing the centralized authentication in origical IKE protocol with immediate authentication. In addition, the two modifications can be integrated into one protocol compactly. 展开更多
关键词 IKE protocol message authentication authenticated key agreement
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ELLIPTIC CURVE CRYPTOGRAPHY BASED AUTHENTICATED KEY AGREEMENT WITH PRE-SHARED PASSWORD 被引量:1
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作者 SuiAifen LucasC.K.Hui +1 位作者 YangYixian K.P.Chow 《Journal of Electronics(China)》 2005年第3期268-272,共5页
Based on elliptic curve Diffie-Hellman algorithm, an Elliptic Curve Authenticated Key Agreement (ECAKA) protocol with pre-shared password is proposed. Its security relies on the Elliptic Curve Discrete Logarithm Probl... Based on elliptic curve Diffie-Hellman algorithm, an Elliptic Curve Authenticated Key Agreement (ECAKA) protocol with pre-shared password is proposed. Its security relies on the Elliptic Curve Discrete Logarithm Problem (ECDLP). It provides identity authentication, key validation and perfect forward secrecy, and it can foil man-in-the-middle attacks. 展开更多
关键词 Elliptic Curve Cryptography (ECC) DIFFIE-HELLMAN Simple Authenticated key Agreement (SAKA)
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Heterogeneous User Authentication and Key Establishment Protocol for Client-Server Environment
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作者 Huihui Zhu Fei Tang +1 位作者 Chunhua Jin Ping Wang 《Computers, Materials & Continua》 2026年第4期648-666,共19页
The ubiquitous adoption of mobile devices as essential platforms for sensitive data transmission has heightened the demand for secure client-server communication.Although various authentication and key agreement proto... The ubiquitous adoption of mobile devices as essential platforms for sensitive data transmission has heightened the demand for secure client-server communication.Although various authentication and key agreement protocols have been developed,current approaches are constrained by homogeneous cryptosystem frameworks,namely public key infrastructure(PKI),identity-based cryptography(IBC),or certificateless cryptography(CLC),each presenting limitations in client-server architectures.Specifically,PKI incurs certificate management overhead,IBC introduces key escrow risks,and CLC encounters cross-system interoperability challenges.To overcome these shortcomings,this study introduces a heterogeneous signcryption-based authentication and key agreement protocol that synergistically integrates IBC for client operations(eliminating PKI’s certificate dependency)with CLC for server implementation(mitigating IBC’s key escrow issue while preserving efficiency).Rigorous security analysis under the mBR(modified Bellare-Rogaway)model confirms the protocol’s resistance to adaptive chosen-ciphertext attacks.Quantitative comparisons demonstrate that the proposed protocol achieves 10.08%–71.34%lower communication overhead than existing schemes across multiple security levels(80-,112-,and 128-bit)compared to existing protocols. 展开更多
关键词 User authentication key establishment CLIENT-SERVER HETEROGENEOUS SECURITY
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Key Techniques for High-yield and High-efficiency Cultivation of‘Zhouhua 5’Peanut under Film Mulching
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作者 Chaoyang JIA Yake LEI +3 位作者 Jianhang ZHANG Shijie ZHAN Chenwei DENG Jingbin CUI 《Agricultural Biotechnology》 2026年第1期13-15,25,共4页
With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall e... With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall economic benefits.Based on the varietal characteristics of‘Zhouhua 5’and addressing practical issues in peanut production,this paper summarized key techniques for high-yield and high-efficiency film mulching cultivation of this variety.These techniques cover all critical stages,including land preparation and fertilization,seed preparation,sowing methods,field management,and timely harvesting,providing technical guidance for varietal promotion and peanut production. 展开更多
关键词 PEANUT Zhouhua 5 Film mulching key technique
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An Anonymous Authentication and Key Exchange Protocol for UAVs in Flying Ad-Hoc Networks
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作者 Yanan Liu Suhao Wang +4 位作者 Lei Cao Pengfei Wang Zheng Zhang Shuo Qiu Ruchan Dong 《Computers, Materials & Continua》 2026年第3期1262-1286,共25页
Unmanned Aerial Vehicles(UAVs)in Flying Ad-Hoc Networks(FANETs)are widely used in both civilian and military fields,but they face severe security,trust,and privacy vulnerabilities due to their high mobility,dynamic to... Unmanned Aerial Vehicles(UAVs)in Flying Ad-Hoc Networks(FANETs)are widely used in both civilian and military fields,but they face severe security,trust,and privacy vulnerabilities due to their high mobility,dynamic topology,and open wireless channels.Existing security protocols for Mobile Ad-Hoc Networks(MANETs)cannot be directly applied to FANETs,as FANETs require lightweight,high real-time performance,and strong anonymity.The current FANETs security protocol cannot simultaneously meet the requirements of strong anonymity,high security,and low overhead in high dynamic and resource-constrained scenarios.To address these challenges,this paper proposes an Anonymous Authentication and Key Exchange Protocol(AAKE-OWA)for UAVs in FANETs based on OneWay Accumulators(OWA).During the UAV registration phase,the Key Management Center(KMC)generates an identity ticket for each UAV using OWA and transmits it securely to the UAV’s on-board tamper-proof module.In the key exchange phase,UAVs generate temporary authentication tickets with random numbers and compute the same session key leveraging the quasi-commutativity of OWA.For mutual anonymous authentication,UAVs encrypt random numbers with the session key and verify identities by comparing computed values with authentication values.Formal analysis using the Scyther tool confirms that the protocol resists identity spoofing,man-in-the-middle,and replay attacks.Through Burrows Abadi Needham(BAN)logic proof,it achieves mutual anonymity,prevents simulation and physical capture attacks,and ensures secure connectivity of 1.Experimental comparisons with existing protocols prove that the AAKE-OWA protocol has lower computational overhead,communication overhead,and storage overhead,making it more suitable for resource-constrained FANET scenarios.Performance comparison experiments show that,compared with other schemes,this scheme only requires 8 one-way accumulator operations and 4 symmetric encryption/decryption operations,with a total computational overhead as low as 2.3504 ms,a communication overhead of merely 1216 bits,and a storage overhead of 768 bits.We have achieved a reduction in computational costs from 6.3%to 90.3%,communication costs from 5.0%to 69.1%,and overall storage costs from 33%to 68%compared to existing solutions.It can meet the performance requirements of lightweight,real-time,and anonymity for unmanned aerial vehicles(UAVs)networks. 展开更多
关键词 AUTHENTICATION key exchange one-way accumulator flying ad-hoc networks SECURITY
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Predicting potential suitable areas of Orchidaceae plants with national key reserve from Heilongjiang province in MaxEnt models
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作者 Weixue Zhong Xiaoxue Wei +6 位作者 Yujia Yu Xiaoqing Tang Ye Zhang Xinyu Huang Xiaohui Li Ying Liu Dewen Li 《Ecological Frontiers》 2026年第1期18-28,共11页
The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and ... The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and 19 bioclimatic variables were selected,and the environmental factors required for modeling were screened out by pearson correlation analysis and variance inflation factor(VIF)analysis.The potential suitable areas of Orchidaceae plants were predictat present and under different climate scenarios in 2090s by using geographic information system(GIS)and Maximum Entropy Model(MaxEnt).And then evaluated the prediction accuracy of the MaxEnt model using the AUC value,the TSS value and the Kappa value.The results showed that:1)The area under curve(AUC)values,true skill statistics(TSS)values and KAPPA values predicted by MaxEnt model were separately above 0.9,0.85 and 0.75.2)Under the climate scenario at present,the total suitable area of Orchidaceae plants was about 9.61×10^(6)km^(2),which was mainly distributed in Heilongjiang province.Among them,the high-suitable area of Cypripedium shanxiense S.C.Chen was the largest,the non-suitable area of Cypripedium guttatum Sw was the largest.3)Under different climate scenarios in 2090s,the total suitable area was slightly increasing(9.62×10^(6)km^(2)).Among them,Cypripedium shanxiense S.C.Chen and Gastrodiae Rhizoma both showed the trend of expansion to the southwest,China,and the suitable areas expanded significantly.Comprehensive factor analysis showed that temperature and precipitation were the main bioclimatic variables of suitable areas distribution,and the low emission scenario(SSP 2-4.5)will be more conducive to the survival of Orchidaceae plants. 展开更多
关键词 Orchidaceae plants Potential suitable areas Bioclimatic variables MaxEnt models National key reserve
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Slope rockbolting using key block theory:Force transfer and artificial intelligence-assisted multi-objective optimisation
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作者 Jessica Ka Yi Chiu Charlie Chunlin Li +1 位作者 Ole Jakob Mengshoel Vidar Kveldsvik 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期73-91,共19页
This paper presents a novel artificial intelligence(AI)-assisted two-stage method for optimising rock slope stability by integrating advanced 3D modelling with rock support design,aiming at minimising risks,material u... This paper presents a novel artificial intelligence(AI)-assisted two-stage method for optimising rock slope stability by integrating advanced 3D modelling with rock support design,aiming at minimising risks,material usage,and costs.In the first stage,an extended key block analysis identifies key blocks and key block groups,accounting for progressive failure and force interactions.The second stage uses AI algorithms to optimise rockbolting design,balancing stability,cost,and material use.The most efficient algorithms include the multi-objective tree-structured Parzen estimator(MOTPE)and non-dominated sorting genetic algorithms(NSGA-II and NSGA-III).Applied to the Larvik rock slope,the optimised solution uses 18 pre-tensioned cablebolts,providing 13.2 MN of active force and achieving a factor of safety of 1.31 while reducing the average anchorage length by approximately 16%compared to traditional design.The AI-assisted approach also reduces computation time by over 90%compared to Quasi-Monte Carlo(QMC)methods,demonstrating its efficiency for small-scale civil engineering projects and large-scale mining operations.The developed tool is practical,compatible with Building Information Modelling(BIM),and ready for engineering implementation,supporting sustainable and cost-effective rock slope stabilisation.While the method is largely automated,professional judgement remains crucial for verifying ground conditions and selecting the final solution.Future work will focus on integrating data uncertainties,addressing complex block deformation mechanisms,refining optimisation objectives,and improving the performance of multi-objective optimisation for slope rockboling applications to further enhance the method's versatility. 展开更多
关键词 Rock anchoring Slope stability 3D modelling key block Parametric design Bio-inspired artificial intelligence(AI)
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Breaking the stranglehold on key technologies:building an integrated"R&D-Application-Promotion"ecosystem for domestic scientific instruments
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作者 Yingli Xu Jing Wang +3 位作者 Xiaomeng Shi Xia Yuan Qian Wang Shuxiang Song 《Journal of Chinese Pharmaceutical Sciences》 2026年第1期88-97,共10页
Scientific instruments serve as foundational pillars for both scientific progress and industrial innovation,enabling deep exploration and driving technological breakthroughs.Their independent controllability and conti... Scientific instruments serve as foundational pillars for both scientific progress and industrial innovation,enabling deep exploration and driving technological breakthroughs.Their independent controllability and continuous innovation are indispensable for sustaining a competitive advantage in technological development,thereby securing national scientific capacity and long-term strategic growth.At present,however,China faces substantial risks of technological"stranglehold"in the high-end scientific instrument domain.The underlying causes are multifaceted,arising not only from insufficient accumulation of core technologies but also from entrenched systemic and ecosystem-level barriers that impede the application,scaling,and promotion of domestic instruments.This paper provides a systematic analysis of the challenges hindering the widespread adoption of domestically developed scientific instruments and proposes practical pathways to build a new,integrated"R&D-application-promotion"ecosystem.This ecosystem is anchored in trust,driven by user demand,and shaped through collaborative innovation.Key initiatives include organizing user visits to instrument manufacturers,convening seminars on domestic alternatives to imported equipment,establishing demonstration centers for application and promotion,and involving end-users directly in the R&D and iterative upgrading of domestic instruments.Together,these efforts aim to close the final critical gap,advancing domestic instruments from merely"functional"to genuinely"user-friendly",and ultimately to"widely implemented".By doing so,this framework offers both theoretical grounding and practical guidance for achieving high-level scientific and technological self-reliance and sustained innovation capacity. 展开更多
关键词 Domestic scientific instruments Strangleholdof key technology Application promotion Industry-university-researchapplication collaboration Scientific and technological self-reliance and strengthening
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Multilevel Military Image Encryption Based on Tri-Independent Keying Approach
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作者 Shereen S.Jumaa Mohsin H.Challoob Amjad J.Humaidi 《Computers, Materials & Continua》 2026年第4期1548-1564,共17页
Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military... Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military images.The proposed encryption method is based on multilevel security stages of pixel-level scrambling,bitlevel manipulation,and block-level shuffling operations.For having a vast key space,the input password is hashed by the Secure Hash Algorithm 256-bit(SHA-256)for generating independently deterministic keys used in the multilevel stages.A piecewise pixel-level scrambling function is introduced to perform a dual flipping process controlled with an adaptive key for obscuring the spatial relationships between the adjacent pixels.Adynamicmasking scheme is presented for conducting a bit-level manipulation based on distinct keys that change over image regions,providing completely different encryption results on identical regions.To handle the global correlation between large-scale patterns,a chaotic index-map system is employed for shuffling image regions randomly across the image domain based on a logistic map seeded with a private key.Experimental results on a dataset of military images show the effectiveness of the proposed encryption method in producing excellent quantitative and qualitative results.The proposed method obtains uniform histogram distributions,high entropy values around the ideal(≈8 bits),Number of Pixel Change Rate(NPCR)values above 99.5%,and low Peak Signal-to-Noise Ratio(PSNR)over all encrypted images.This validates the robustness of the proposed method against cryptanalytic attacks,verifying its ability to serve as a practical basis for secure image transmission in defense systems. 展开更多
关键词 Military image encryption pixel-level scrambling bit-level manipulation block-level shuffling password hashing dynamic encryption key spatial pixel correlation chaotic system
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MS-RWKV-UNet:Multi-Head Scan Receptance Weighted Key Value UNet for Medical Image Segmentation
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作者 JIANG Dong JI Zhongping FANG Meie 《Wuhan University Journal of Natural Sciences》 2026年第1期1-9,共9页
The Transformer has achieved great success in the field of medical image segmentation,but its quadratic computational complexity limits its application in dense medical image prediction.Recently,the receptance weighte... The Transformer has achieved great success in the field of medical image segmentation,but its quadratic computational complexity limits its application in dense medical image prediction.Recently,the receptance weighted key value(RWKV)architecture has garnered widespread attention due to its linear computational complexity and its capability of parallel computation during training.Despite the RWKV model's proficiency in addressing long-range modeling tasks with linear computational complexity,most current RWKV-based approaches employ static scanning patterns.These patterns may inadvertently incorporate biased prior knowledge into the model's predictions.To address this challenge,we propose a multi-head scan strategy combined with padding methods to effectively simulate spatial continuity in 2D images.Within the Feature Aggregation Attention(FAA)module,asymmetric convolutions are designed to aggregate 1D sequence features along a single dimension,thereby expanding effective receptive fields while preserving structural sparsity.Additionally,panoramic token shift(P-Shift)effectively models local dependency relationships by moving tokens from a wide receptive field.Extensive experiments conducted on the ISIC17/18 and ACDC datasets demonstrate that our method exhibits superior performance in dense medical image prediction tasks. 展开更多
关键词 multi-head scan receptance weighted key value(RWKV) asymmetric convolution panoramic token shift(P-Shift) medical image segmentation
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KPA-ViT:Key Part-Level Attention Vision Transformer for Foreign Body Classification on Coal Conveyor Belt
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作者 Haoxuanye Ji Zhiliang Chen +3 位作者 Pengfei Jiang Ziyue Wang Ting Yu Wei Zhang 《Computers, Materials & Continua》 2026年第3期656-671,共16页
Foreign body classification on coal conveyor belts is a critical component of intelligent coal mining systems.Previous approaches have primarily utilized convolutional neural networks(CNNs)to effectively integrate spa... Foreign body classification on coal conveyor belts is a critical component of intelligent coal mining systems.Previous approaches have primarily utilized convolutional neural networks(CNNs)to effectively integrate spatial and semantic information.However,the performance of CNN-based methods remains limited in classification accuracy,primarily due to insufficient exploration of local image characteristics.Unlike CNNs,Vision Transformer(ViT)captures discriminative features by modeling relationships between local image patches.However,such methods typically require a large number of training samples to perform effectively.In the context of foreign body classification on coal conveyor belts,the limited availability of training samples hinders the full exploitation of Vision Transformer’s(ViT)capabilities.To address this issue,we propose an efficient approach,termed Key Part-level Attention Vision Transformer(KPA-ViT),which incorporates key local information into the transformer architecture to enrich the training information.It comprises three main components:a key-point detection module,a key local mining module,and an attention module.To extract key local regions,a key-point detection strategy is first employed to identify the positions of key points.Subsequently,the key local mining module extracts the relevant local features based on these detected points.Finally,an attention module composed of self-attention and cross-attention blocks is introduced to integrate global and key part-level information,thereby enhancing the model’s ability to learn discriminative features.Compared to recent transformer-based frameworks—such as ViT,Swin-Transformer,and EfficientViT—the proposed KPA-ViT achieves performance improvements of 9.3%,6.6%,and 2.8%,respectively,on the CUMT-BelT dataset,demonstrating its effectiveness. 展开更多
关键词 Foreign body classification global and part-level key information coal conveyor belt vision transformer(ViT) self and cross attention
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Embodied-Intelligence Power Industrial Control Systems:Architecture Design,Key Scientific Problems,and Research Recommendations
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作者 Tingjun Zhang Dong Yue 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期239-242,共4页
THE power industrial control system(power ICS)is thecore infrastructure that ensures the safe,stable,and efficient operation of power systems.Its architecture typi-cally adopts a hierarchical and partitioned end-edge-... THE power industrial control system(power ICS)is thecore infrastructure that ensures the safe,stable,and efficient operation of power systems.Its architecture typi-cally adopts a hierarchical and partitioned end-edge-cloud collaborative design.However,the large-scale integration ofdistributed renewable energy resources,coupled with the extensivedeployment of sensing and communication devices,has resulted inthe new-type power system characterized by dynamic complexityand high uncertainty[1]-[4]. 展开更多
关键词 power system embodied intelligence power industrial control system power architecture design key scientific problems power industrial control systems sensing communication deviceshas renewable energy resourcescoupled
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融合代理重加密和零知识证明的USBKey联盟链追溯系统 被引量:2
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作者 张磊 万昕元 +3 位作者 肖超恩 王建新 邓昊东 郑玉崝 《信息安全研究》 北大核心 2025年第1期81-90,共10页
目前,基于区块链技术的信息追溯系统在物联网领域中得到了广泛应用.但是,基于区块链的追溯系统在追溯数据存储和查询的过程中存在数据及用户隐私泄露的风险.针对此类问题,融合代理重加密和零知识证明技术,设计了基于联盟链构造的USB Ke... 目前,基于区块链技术的信息追溯系统在物联网领域中得到了广泛应用.但是,基于区块链的追溯系统在追溯数据存储和查询的过程中存在数据及用户隐私泄露的风险.针对此类问题,融合代理重加密和零知识证明技术,设计了基于联盟链构造的USB Key可信追溯解决方案.首先,在区块链上链存储过程中引入了星际文件系统(interplanetary file system,IPFS)和代理重加密技术,为参与双方建立了一个安全、高效的信息存储机制;同时,在数据查询过程中引入了zk-SNARK零知识证明机制,对查询用户进行身份认证和确权操作,确保了追溯数据查询过程中用户身份的私密性;最后,基于上述可信追溯解决方案,利用Hyperledger Fabric分布式账本实现了一个USB Key的信息追溯原型系统.通过实验,证明了该方案切实可行,并有效地保障了USB Key追溯系统中追溯信息的保密性和真实性,以及在实现权限分配的前提下用户身份的隐私性. 展开更多
关键词 USB key 代理重加密 零知识证明 区块链 信息追溯
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Aerodynamic uplift force improvement in single-strip high-speed pantograph via key parameter regulation with mechanism investigation 被引量:1
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作者 Yafeng Zou Xianghong Xu +2 位作者 Rui Zhou Zichen Liu Liming Lin 《Theoretical & Applied Mechanics Letters》 2025年第4期378-387,共10页
This study addresses the significant disparity in aerodynamic uplift forces experienced by single-strip high-speed pantographs under different operating directions.A systematic numerical investigation was conducted to... This study addresses the significant disparity in aerodynamic uplift forces experienced by single-strip high-speed pantographs under different operating directions.A systematic numerical investigation was conducted to evaluate the influence of key geometric parameters on aerodynamic characteristics,culminating in two targeted adjustment strategies.The reliability of the computational methodology was validated through comparative analysis,which revealed less than a 6%deviation in aerodynamic drag between the numerical simulations and wind tunnel tests.Aerodynamic decomposition revealed that the operating direction critically impacts the uplift force,which is governed by two factors:streamwise cross-strip positioning and the angular orientation of the arm hinge.These factors collectively determine the divergent aerodynamic responses of the panhead and frame during directional changes.By establishing a parametric database encompassing four strip-to-crossbar spacing configurations and six arm diameter variations,nonlinear response patterns of the uplift forces under different operating directions to geometric modifications were quantified.Both adjustment approaches,simultaneously reducing both streamwise and vertical strip-to-crossbar spacings to half of the original dimensions or increasing the upper arm spanwise diameter to 1.45 times and decreasing the lower arm spanwise diameter to 0.55 times the baseline values,successfully constrained aerodynamic uplift force deviations between operating directions within 3%. 展开更多
关键词 High-speed pantograph Aerodynamic uplift force key parameter regulation Numerical simulation
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BCDH:Blockchain-based covert Diffie-Hellman key exchange scheme 被引量:1
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作者 Qinghua Hu Chunxiang Xu Wanpeng Li 《Defence Technology(防务技术)》 2025年第10期24-31,共8页
The purpose of the covert communication scheme is to conceal the communication behavior entirely.In such schemes,the sender and receiver rely on secret keys to establish a covert channel.However,conventional key excha... The purpose of the covert communication scheme is to conceal the communication behavior entirely.In such schemes,the sender and receiver rely on secret keys to establish a covert channel.However,conventional key exchange protocols would expose the key exchange process between them.An adversary who observes the key exchange would be aware of the existence of communication behavior.The keys used in covert communication are not suitable to be generated through conventional key exchange schemes.To address this,we propose a blockchain-based covert elliptic-curve Diffie-Hellman key exchange scheme(BCDH)to conceal the process of the key exchange in blockchain transactions.Following a straightforward setup,BCDH allows the sender and receiver to covertly exchange a secret key on a blockchain without direct communication.Furthermore,we expand the BCDH approach to operate across multiple blockchains,further enhancing its covertness and stability.We analyze BCDH from several perspectives,including covertness,security,randomness,etc.Additionally,we implement a prototype of BCDH on the Ethereum platform to assess its feasibility and performance.Our evaluation demonstrates that BCDH is efficient and well-suited for real-world applications. 展开更多
关键词 Diffie-Hellman key exchange Digital signature Covert communication Blockchain Blockchain-based covert communication
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Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables
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作者 Ao Shen Zhiquan Lai +1 位作者 Dongsheng Li Xiaoyu Hu 《Computers, Materials & Continua》 SCIE EI 2025年第1期307-325,共19页
Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in speci... Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader deployment.Parameter-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational efficiency.Among these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA variants.Despite these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains underexplored.This study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM architectures.Our investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do so.These insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized LLMs.Moreover,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller one.This study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM fine-tuning in resource-constrained environments. 展开更多
关键词 Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis
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Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing
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作者 Haolan Ren Fei Zheng +1 位作者 Tingwei Cao Qiang Wang 《Atmospheric and Oceanic Science Letters》 2025年第1期39-45,共7页
Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in c... Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale. 展开更多
关键词 Recovery of AMOC 4×CO_(2) forcing key parameter Parameter estimation Data assimilation Machine learning
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Practical 15 Mb/s Quantum Key Distribution Using Compact Single-Photon Detectors
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作者 Tingting Shi Zhengyu Yan +4 位作者 Yuanbin Fan Lai Zhou Yuanfei Gao Davide G.Marangon Zhiliang Yuan 《Chinese Physics Letters》 2025年第12期172-177,共6页
Quantum key distribution(QKD)is recognized as an unconditionally secure method of communication encryption,relying solely on the principles of quantum mechanics.A key performance metric for QKD systems is secure key r... Quantum key distribution(QKD)is recognized as an unconditionally secure method of communication encryption,relying solely on the principles of quantum mechanics.A key performance metric for QKD systems is secure key rate(SKR),which is a critical factor for real-world applications.Herein,we report a practical QKD system,equipped with compact gated InGaAs/InP single-photon detectors(SPDs),that can generate a high SKR of 15.2 Mb/s with a channel loss of 2 dB.This exceptional performance stems from the ultra-low afterpulsing probability of the SPDs,which significantly reduces the bit error rate in the QKD system.The typical quantum bit error rate is 1.3%.The results validate the feasibility of an integrated,practical QKD system and offer a reliable solution for the future development of real-world QKD networks. 展开更多
关键词 quantum key distribution qkd afterpulsing probability secure key rate quantum key distribution single photon detectors secure key rate skr which bit error rate
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Key Agreement and Management Scheme Based on Blockchain for 5G-Enabled Vehicular Networks
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作者 Wang Zhihua Wang Shuaibo +4 位作者 Wang Haofan Li Jiaze Yao Yizhe Wang Yongjian Yang Xiaolong 《China Communications》 2025年第3期270-287,共18页
5G technology has endowed mobile communication terminals with features such as ultrawideband access,low latency,and high reliability transmission,which can complete the network access and interconnection of a large nu... 5G technology has endowed mobile communication terminals with features such as ultrawideband access,low latency,and high reliability transmission,which can complete the network access and interconnection of a large number of devices,thus realizing richer application scenarios and constructing 5G-enabled vehicular networks.However,due to the vulnerability of wireless communication,vehicle privacy and communication security have become the key problems to be solved in vehicular networks.Moreover,the large-scale communication in the vehicular networks also makes the higher communication efficiency an inevitable requirement.In order to achieve efficient and secure communication while protecting vehicle privacy,this paper proposes a lightweight key agreement and key update scheme for 5G vehicular networks based on blockchain.Firstly,the key agreement is accomplished using certificateless public key cryptography,and based on the aggregate signature and the cooperation between the vehicle and the trusted authority,an efficient key updating method is proposed,which reduces the overhead and protects the privacy of the vehicle while ensuring the communication security.Secondly,by introducing blockchain and using smart contracts to load the vehicle public key table for key management,this meets the requirements of vehicle traceability and can dynamically track and revoke misbehaving vehicles.Finally,the formal security proof under the eck security model and the informal security analysis is conducted,it turns out that our scheme is more secure than other authentication schemes in the vehicular networks.Performance analysis shows that our scheme has lower overhead than existing schemes in terms of communication and computation. 展开更多
关键词 blockchain certificateless public key cryptography 5G vehicular networks key agreement key management
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State Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization
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《China Rare Earth Information》 2025年第2期F0002-F0002,共1页
State Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization was approved by the Ministry of Science and Technology to be one of the national key laboratories in November 2022.
关键词 key laboratories State key Laboratory rare earth resource National key Laboratories Baiyun Obo Rare Earth Resources Ministry Science Technology Comprehensive Utilization key laboratory
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