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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian li-Cai liu Zhi-Hao Chen Yuan liu Yin li Qingjiang li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organoborons are useful building blocks and key structural elements in functional *** previous synthesis relied on the famous Matteson reaction or the late-stage borylative modification of alkynes or ***,the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively *** report herein that B(MIDA)-propargylic alcohols(BPAs) are a useful type of borylated building *** two complementary functional group handles(alkyne and hydroxyl) in close proximity,the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates,including α,β-unsaturated acylborons,α-S/P-substituted allenylborons,boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine,some of which are otherwise challenging targets using other synthetic methods.

关键词： organoboron diverse synthesis sigmatropic rearrangement heteroarene amide

Input-to-State Stability of Impulsive Switched Systems Involving Uncertain Impulse-Switching Moments

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1515-1517页

作者： Chang liu Wenlu liu Tengda Wei Xiaodi li School of Mathematical and Statistics Shandong Normal UniversityJinan 250014China

Dear Editor,This letter studies the input-to-state stability(ISS)for a class of impulsive switched systems,where uncertain impulse-switching moments are *** robustness of ISS with respect to the perturbations of the occurrence time of impulse-switching moments is revealed by several less conservative dwell-time conditions for the uncertain impulse-switching moments combined with Lyapunov ***,the Lyapunov conditions have multiple coefficients at discrete time so as to handle the hybrid effect of impulse-switching moments,and the case that time derivative of Lyapunov function is indefinite is also taken into ***,a numerical example is proposed to illustrate the effectiveness of the theoretical results.

关键词： letter conservative derivative

Constructing the Impossible Differential of Type-II GFN with Boolean Function and Its Application to WARP

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Chinese Journal of Electronics 2024年第1期33卷 80-89页

作者： Jiali SHI Guoqiang liu Chao li College of liberal Arts and Sciences National University of Defense Technology Hunan Engineering Research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering

Type-Ⅱ generalized Feist el network(GFN) has attracted a lot of attention for its simplicity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-like *** deduce the impossible differential of Type-Ⅱ GFN by analyzing the Boolean function in the middle *** main idea is to investigate the expression with the variable representing the plaintext(ciphertext) difference words for the internal state *** adopting the miss-in-the-middle approach,we can construct the impossible differential of Type-Ⅱ *** an illustration,we apply this approach to WARP,a lightweight 128-bit block cipher with a 128-bit key which was presented by Banik et *** SAC *** structure of WARP is a 32-branch Type-Ⅱ ***,we find two 21-round truncated impossible differentials and implement a 32-round key recovery attack on *** the 32-round key recovery attack on WARP,some observations are used to mount an effective *** the advantage of the early abort technique,the data,time,and memory complexities are 2125.69chosen plaintexts,2126.6832-round encryptions,and 2100-bit,*** the best of our knowledge,this is the best attack on WARP in the single-key scenario.

关键词： Ciphers Boolean functions Parallel processing Complexity theory

Bandgap adjustment of a sandwich-like acoustic metamaterial plate with a frequency-displacement feedback control method

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1807-1820页

作者： Jianing liu Jinqiang li Ying WU School of Aerospace Engineering Xi’an Jiaotong UniversityXi’an 710049China College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

Several types of acoustic metamaterials composed of resonant units have been developed to achieve low-frequency *** most of these structures,bandgaps are determined by their geometric configurations and material *** paper presents a frequency-displacement feedback control method for vibration suppression in a sandwich-like acoustic metamaterial *** band structure is theoretically derived using the Hamilton principle and validated by comparing the theoretical calculation results with the finite element simulation *** this method,the feedback voltage is related to the displacement of a resonator and the excitation *** applying a feedback voltage on the piezoelectric fiber-reinforced composite(PFRC)layers attached to a cantilever-mass resonator,the natural frequency of the resonator can be *** ensures that the bandgap moves in a frequency-dependent manner to keep the excitation frequency within the *** on this frequency-displacement feedback control strategy,the bandgap of the metamaterial plate can be effectively adjusted,and the vibration of the metamaterial plate can be significantly suppressed.

关键词： acoustic metamaterial Hamilton principle electromechanical coupling vibration control local resonance

A numerical simulation strategy for a compressor’s underlying axisymmetric characteristic and its application in body force model

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Chinese Journal of Aeronautics 2024年第8期37卷 79-90页

作者： Shijie liu Tianyu PAN Qiushi li School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Accurate prediction of the aerodynamic response of a compressor under inlet distortion is crucial for next-generation civil aircraft,such as Boundary Layer Ingestion(Bli)silent ***,research on the Body Force(BF)model plays a significant role in achieving this ***,distorted inlet airflow can lead to varying operating conditions across different spatial locations of the compressor,which may cause some regions to operate outside the stability ***,the accuracy of BF model simulations might be *** address this issue,this paper proposes a numerical simulation strategy for acquiring the steady axisymmetric three-dimensional flow field of a compressor operating at low mass flow rates,which is known as the Underlying Axisymmetric Pressure Rise Characteristic(UAPRC).The proposed simulation accounts for two different rotor speeds of a transonic compressor and identifies initial positions in the flow field where deterioration occurs based on prior experimental ***,simulation results are incorporated into the BF model to replicate hub instability observed in *** results demonstrate that this strategy provides valid predictions of the UAPRC of the compressor,thereby addressing the limitations associated with the BF model.

关键词： Compressor partial instability Performance at low mass flow rates Underlying axisymmetric pressure rise characteristic Novel simulation strategy Body force model

Topological magnetoelectric response in ferromagnetic axion insulators

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National Science Review 2024年第2期11卷 8-14页

作者： Yuhao Wan Jiayu li Qihang liu Department of Physics and Shenzhen Institute for Quantum Science and Engineering(SIQSE) Southern University of Science and Technology Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and Technology Guangdong Provincial Key Laboratory for Computational Science and Material Design Southern University of Science and Technology

The topological magnetoelectric effect （TME） is a hallmark response of the topological field theory,which provides a paradigm shift in the study of emergent topological ***,its direct observation is yet to be realized due to the demanding magnetic configuration required to gap all surface ***,we theoretically propose that axion insulators with a simple ferromagnetic configuration,such as the MnBi2Te4/（Bi2Te3）nfamily,provide an ideal playground to realize the *** the designed triangular prism geometry,all the surface states are magnetically *** a vertical electric field,the surface Hall currents give rise to a nearly half-quantized orbital moment,accompanied by a gapless chiral hinge mode circulating in ***,the orbital magnetization from the two topological origins can be easily distinguished by reversing the electric *** work paves the way for direct observation of the TME in realistic axion-insulator materials.

关键词： topological magnetoelectric effect axion insulator magnetic topological materials

Tribological study of two ammonium chloride-decanoic acid deep eutectic solvents(DESs)as high-performance lubricants

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Friction 2024年第11期12卷 2441-2457页

作者： Zhuocheng li Enhui ZHANG Weimin li Haichao liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Zibo Innovation Center of High-End Synthetic Lubricating Materials Zibo 255000China

Deep eutectic solvents(DESs)are acknowledged as a novel class of functional *** share similar physical properties with ionic liquids(ILs)and have the potential to be a novel class of *** this study,two DESs,namely tetrabutylammonium chloride-decanoic acid DES(C4-DES)and methyl tricaprylmethylammonium chloride-decanoic acid DES(C8-DES),were synthesized,and their physico-chemical properties and tribological performances were ***-analysis of the rubbing surfaces used multiple techniques to gain insights into the lubrication *** show that the coefficient of friction(COF)and wear were reduced by approximately 29%and 91%for the C4-DES,and 36%and 94%for the C8-DES,compared to an ester base *** friction reduction behavior of the DESs is attributed to the monolayer adsorption of the polar group in the decanoic acid(DEAC),whose effectiveness is affected by the component of the ammonium salts in the DESs and the operating *** addition to the adsorbed film,worn surface analysis revealed that an ultra-thin tribochemical film with a thickness of 3–7 nm was formed on the surfaces lubricated with the *** composition of the film was studied,and the lubrication mechanisms of the two DESs were discussed.

关键词： deep eutectic solvent(DES) lubricants tribological performance boundary lubrication

Experimental Data-Driven Flow Field Prediction for Compressor Cascade based on Deep Learning and l_(1)Regularization

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Journal of Thermal Science 2024年第5期33卷 1867-1882页

作者： liu Tantao GAO limin li Ruiyu School of Power and Energy Northwestern Polytechnical UniversityXi'an 710012China School of Aerospace Engineering Xi'an Jiaotong UniversityXi'an 710049China

For complex flows in compressors containing flow separations and adverse pressure gradients,the numerical simulation results based on Reynolds-averaged Navier-Stokes(RANS)models often deviate from experimental measurements more or *** improve the prediction accuracy and reduce the difference between the RANS prediction results and experimental measurements,an experimental data-driven flow field prediction method based on deep learning and l_(1)regularization is proposed and applied to a compressor cascade flow *** inlet boundary conditions and turbulence model parameters are calibrated to obtain the high-fidelity flow *** Saplart-Allmaras and SST turbulence models are used independently for mutual *** contributions of key modified parameters are also analyzed via sensitivity *** results show that the prediction error can be reduced by nearly 70%based on the proposed *** flow fields predicted by the two calibrated turbulence models are almost the same and nearly independent of the turbulence *** corrections of the inlet boundary conditions reduce the error in the first half of the *** turbulence model calibrations fix the overprediction of flow separation on the suction surface near the tail edge.

关键词： experimental data-driven compressor cascade deep learning l_(1)regularization

FedDAA:a robust federated learning framework to protect privacy and defend against adversarial attack

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Frontiers of Computer Science 2024年第2期18卷 107-122页

作者： Shiwei LU Ruihu li Wenbin liu Fundamentals Department Air Force Engineering UniversityXi’an 710051China Institute of Advanced Computational Science and Technology Guangzhou UniversityGuangzhou 510006China

Federated learning(FL)has emerged to break data-silo and protect clients’privacy in the field of artificial ***,deep leakage from gradient(DLG)attack can fully reconstruct clients’data from the submitted gradient,which threatens the fundamental privacy of *** cryptology and differential privacy prevent privacy leakage from gradient,they bring negative effect on communication overhead or model ***,the original distribution of local gradient has been changed in these schemes,which makes it difficult to defend against adversarial *** this paper,we propose a novel federated learning framework with model decomposition,aggregation and assembling(FedDAA),along with a training algorithm,to train federated model,where local gradient is decomposed into multiple blocks and sent to different proxy servers to complete *** bring better privacy protection performance to FedDAA,an indicator is designed based on image structural similarity to measure privacy leakage under DLG attack and an optimization method is given to protect privacy with the least proxy *** addition,we give defense schemes against adversarial attack in FedDAA and design an algorithm to verify the correctness of aggregated *** results demonstrate that FedDAA can reduce the structural similarity between the reconstructed image and the original image to 0.014 and remain model convergence accuracy as 0.952,thus having the best privacy protection performance and model training *** importantly,defense schemes against adversarial attack are compatible with privacy protection in FedDAA and the defense effects are not weaker than those in the traditional ***,verification algorithm of aggregation results brings about negligible overhead to FedDAA.

关键词： federated learning privacy protection adversarial attacks aggregated rule correctness verification

A Two-stage Service-oriented Task Offloading Framework with Edge-cloud Collaboration:A Game Theory Approach

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 521-551页

作者： Shiyong li Wenzhe li Huan liu Wei Sun School of Economics and Management Yanshan UniversityQinhuangdao 066004

With the fast development of Mobile Internet,data traffic generated by end devices is anticipated to witness substantial growth in the future ***,processing tasks locally will cause latency due to the limited resources of the end ***-cloud collaboration,an effective solution for latency-sensitive applications,is attracting greater attention from both industry and *** combines the advantages of the cloud center with abundant computing resources and edge nodes with low-latency *** this paper,we propose a two-stage task offloading framework with edge-cloud collaboration to assist end devices processing latency-sensitive tasks either on the edge servers or in the cloud *** for homogeneous task offloading,in the first stage,the competitive end devices offload tasks to the edge *** formulate the selfish task offloading problem among end devices as a potential *** the second stage,the edge nodes request resources from the cloud center to process end devices tasks due to their limited ***,we consider the heterogeneous task offloading problem and use intelligent optimization algorithm to obtain the optimal offloading *** results show that the service prices of edge nodes influence the decisions and task offloading costs of end *** also verify the intelligent optimization algorithm can achieve optimal performance with low complexity and fast convergence.

关键词： Edge-cloud collaboration task offloading potential game simulation annealing algorithm