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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

Research on the macro-and meso-mechanical properties of frozen sand mold based on Hertz-Mindlin with Bonding model

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Particuology 2024年第5期88卷 176-191页

作者： Jianpei shi zhongde Shan Haoqin Yang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this study,macro-and meso-mechanical properties of frozen sand molds were discussed based on the Hertz-Mindlin with Bonding(HMB)***-Burman,steepest ascent,and central composite designs were utilized to propose a parameter calibration *** effects of mesoscopic parameter variations on the compressive strength and average gradient of stress-strain were investigated through response surface method *** showed that the relative error between the simulated and measured repose angle is 3.1%under calibrated intrinsic contact *** compressive strength and average stress-strain gradient primarily depend on the normal and shear stiffness per unit area,as well as the particle size and porosity of the silica ***,taking load-displacement curves of three frozen sand molds with different geometric characteristics as the target value,the reliability and effectiveness of the frozen sand mold HMB model were verified through uniaxial compression tests and discrete element simulations.

关键词： Frozen sand mold Hertz-Mindlin with Bonding model Uniaxial compression test Discrete element method Mechanical properties

Motion-pressure coupled control and simulation of long-endurance capability for multicapsule stratospheric airships

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Chinese Journal of Aeronautics 2024年第6期37卷 137-150页

作者： Zhiguang shi Wei HUO Zongyu ZUO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Beijing Near Space Airship Technology Development Co. LtdBeijing 100070China

The current study focuses on the motion-pressure coupled control for a multicapsule stratospheric airship and transforms the path-tracking and heading-hold control of airships into guidance tracking with a time-varying weighted sum of longitudinal and lateral velocities by the definition of compound ***,an improved nonlinear predictive control method is provided to reduce the control energy consumption by the rolling optimization of controller parameters based on finite time intervals,ensuring infinite-time path-tracking ***,combined with the proposed cyclic regulation process of safe pressure between internal and external capsules,this study can fully reflect the force-thermal coupled rule of airships under the actions of atmospheric environment and maneuvering force,while evaluating the long-endurance capability of airships under the conditions of safe superheating and *** effectiveness of the motionpressure coupled controller was verified through numerical simulations,which can overcome the influence of environmental wind and achieve a tracking effect for the desired cruise path and compound *** airspeed provided during the cyclic circadian time caused the maximum superheating of the helium controlled within 30*** helium in the internal and external capsules achieved circadian *** equivalent micropore diameter of the capsule of 5 mm can achieve 55 days of long-endurance *** controller satisfies the requirements of cruise-flight application modes for multicapsule stratospheric airships with important engineering value.

关键词： Compound speed Nonlinear predictive control Cyclic pressure regulation Long-endurance capability Stratospheric airship

On Isodual Double Toeplitz Codes

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Journal of Systems Science & Complexity 2024年第5期37卷 2196-2206页

作者： shi Minjia XU Li SOLé Patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education School of Mathematical Sciences Anhui University State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences CNRS University of Aix Marseille Centrale Marseille

Double Toeplitz（shortly DT） codes are introduced here as a generalization of double circulant codes. The authors show that such a code is isodual, hence formally self-dual（FSD）. FSD codes form a far-reaching generalization of self-dual codes, the most important class of codes of rate one-half. Self-dual DT codes are characterized as double circulant or double negacirculant. Likewise, even binary DT codes are characterized as double circulant. Numerical examples obtained by exhaustive search show that the codes constructed have best-known minimum distance, up to one unit, amongst formally self-dual codes, and sometimes improve on the known values. For q = 2, the authors find four improvements on the best-known values of the minimum distance of FSD codes. Over F4an explicit construction of DT codes, based on quadratic residues in a prime field, performs equally well. The authors show that DT codes are asymptotically good over Fq. Specifically, the authors construct DT codes arbitrarily close to the asymptotic Varshamov-Gilbert bound for codes of rate one half.

关键词： Double circulant codes double Toeplitz codes formally self-dual codes isodual codes

General Mean-Field BDSDEs with Continuous and Stochastic Linear Growth Coefficients

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Journal of Systems Science & Complexity 2024年第5期37卷 1887-1906页

作者： WANG Jinghan shi Yufeng ZHAO Nana Institute for Financial Studies Shandong University Zhiyuan School of Liberal Arts Beijing Institute of Petrochemical Technology

In this paper, the authors study a class of general mean-field BDSDEs whose coefficients satisfy some stochastic conditions. Specifically, the authors prove the existence and uniqueness theorem of solution under stochastic Lipschitz condition and obtain the related comparison theorem. Besides,the authors further relax the conditions and deduce the existence theorem of solutions under stochastic linear growth and continuous conditions, and the authors also prove the associated comparison ***, an asset pricing problem is discussed, which demonstrates the application of the general mean-field BDSDEs in finance.

关键词： Backward doubly stochastic differential equations comparison theorem mean-field stochastic conditions Wasserstein metric

Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective

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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-Heng Du Yong-Min shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-Ri Zhang Yong-Hua shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Design and Gait Planning of a Worm-inspired Metameric Robot for Pipe Crawling

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Journal of Bionic Engineering 2024年第3期21卷 1265-1277页

作者： Yu Liu Qingbiao shi Zhen Chen Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen361102China

The earthworm has been attracted much attention in the research and development of biomimetic robots due to their unique locomotion mechanism,compact structure,and small motion *** paper presents a new design and prototype of a worm-inspired metameric robot with a movement pattern similar to that of *** robot consists of multiple telescopic modules connected in series through joint *** telescopic module mimics the contraction and elongation motion modes of the earthworm segments.A kinematic and dynamic analysis is conducted on the telescopic module,and an input torque calculation method is provided to ensure sufficient friction between the robot and the pipe *** gait modes of the prototype robot for straight and turning locomotion are introduced,and these modes are extended to robots constructed by different numbers of telescopic *** addition,a method is proposed to increase the friction between the robot and the pipe wall in the aforementioned gait modes without changing the robot structure,thereby improving the robot’s motion ability in *** theoretical model of gait modes has also been validated through gait *** findings of this paper would provide a useful basis for the design,modeling,and control of future worm inspired robots.

关键词： Bio-inspired robot Spatial linkage mechanism Kinematics model Peristaltic locomotion

Electrochemical behavior of tantalum in ethylene carbonate and aluminum chloride solvate ionic liquid

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Transactions of Nonferrous Metals Society of China 2020年第8期30卷 2283-2292页

作者： Ai-min LIU Meng-xia GUO Zi-yang LÜ Bao-guo ZHANG Feng-guo LIU Wen-ju TAO You-jian YANG Xian-wei HU Zhao-wen WANG Yu-bao LIU zhong-ning shi Key Laboratory for Ecological Metallurgy of Multimetallic Mineral Ministry of EducationNortheastern UniversityShenyang 110819China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

To investigate the electrochemical reduction mechanism of Ta(Ⅴ)in ethylene carbonate and aluminum chloride(EC-AlCl3)solvate ionic liquid,cyclic voltammetry experiments were conducted on a tungsten working *** reduction peaks were observed in the cyclic voltammogram of the EC-AlCl3-TaCl5 ionic *** reduction peaks at-0.55,-0.72,and-1.12 V(vs Al)were related to the reduction of Ta(Ⅴ)to tantalum metal by three stages including the formation of Ta(Ⅳ)and Ta(Ⅲ)complex *** reduction of Ta(Ⅲ)to tantalum metal was an irreversible diffusion-controlled reaction with a diffusion coefficient of 3.7×10^-7 cm^2/s at 323 K,and the diffusion activation energy was 77 k J/***,the cathode products at 323 K were characterized by scanning electron microscopy,energy-dispersive spectroscopy,and X-ray photoelectron *** results showed that tantalum metal and tantalum oxides were obtained by potentiostatic electrodeposition at-0.8 V for 2 h.

关键词： electrochemical behavior ionic liquid cyclic voltammetry aluminum chloride tantalum