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Matrix orthogonal polynomials,non-abeli.n Toda lattices,and Bäcklund transformations

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Science China Mathematics 2024年第9期67卷 2071-2090页

作者： shi-Hao li Department of Mathematics Sichuan UniversityChengdu 610064China

A connection between matrix orthogonal polynomials and non-abeli.n integrable lattices is investigated in this *** normali.ation factors of matrix orthogonal polynomials expressed using quasideterminants are shown to be the solutions to the non-abeli.n Toda lattice in semi-discrete and full-discrete ***,with a moment modification method,we demonstrate that the B¨acklund transformation of the non-abeli.n Toda lattice given by Popowicz(1983)is equivalent to the non-abeli.n Volterra lattice,whose solutions can be expressed using quasi-determinants as well.

关键词： matrix orthogonal polynomial non-abeli.n Toda lattice Backlund transformation quasideterminant technique

Constructing the impossible Differential of Type-ii GFn with Boolean Function and its Appli.ation 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 li. Chao li College of li.eral 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 generali.ed Feist el network(GFn) has attracted a lot of attention for its simpli.ity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-li.e *** 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 li.htweight 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

On isodual Double Toepli.z 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 intelli.ent 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 Toepli.z（shortly DT） codes are introduced here as a generali.ation of double circulant codes. The authors show that such a code is isodual, hence formally self-dual（FSD）. FSD codes form a far-reaching generali.ation 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. li.ewise, 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 expli.it 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 Toepli.z codes formally self-dual codes isodual codes

Rhodium-catalyzed addition reactions of benzyli. C–H bonds to cycli. n-sulfonyl ketimines viaπ-coordination

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Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong li.Hang shi Department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China institute of natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availabili.y of nucleophiles and ***,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzyli. *** this study,we present a novel approach for the construction of n-sulfonyl amines via rhodium-catalyzed addition of unbiased benzyli. C–H bonds to cycli. n-sulfonyl ketamines throughπ-*** strategy enables the synthesis of a diverse range of n-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzyli. deprotonation Cycli. n–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

Theory and test of underground explosions:Coupli.g rule between cratering and ground shock

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Underground Space 2024年第4期17卷 146-160页

作者： Wei Guo Jie li.Benjun shi Tianhan Xu Xiaohui Xu Gan li.Jie shi State Key Laboratory of Disaster Prevention and Mitigation of Explosion and impact Army Engineering University of PLANanjing 210007China

Calculating the parameters of the ground shock induced by an underground explosion is a complex energy coupli.g *** is difficult to establi.h a unified ground shock coupli.g law from li.ited test *** paper summarizes the research results obtained at home and abroad and systematically analyzes the coupli.g mechanism of craters formed by an underground explosion and the ground *** differences between the concepts of"closed-explosion critical depth"and"equivalent closed-explosion critical depth"are clearly *** spreading of the ground shock energy is attributed to the explosive expansion of the air cavity,reveali.g a li.ear relationship between the volume of the cavity region(or the volume of the crack region)and the ground shock energy associated with the underground *** proportionali.y factor is related to the mechanical properties of the medium and is independent of the magnitude of the explosion *** on this,a theoretical calculation formula and conversion method for the ground shock coupli.g coefficient were *** tests were conducted in clay and Plexiglass under varying burial *** test results were consistent with the theoretically calculated *** study provides a theoretical basis for the design of explosion-resistant structures in underground engineering.

关键词： Underground explosion Ground shock coupli.g Coupli.g coefficient Equivalent closed explosion Experimental study

Physiological and pathological functions of circular RnAs in the nervous system

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neural Regeneration Research 2024年第2期19卷 342-349页

作者： Min Zhou shi li.Chuan Huang School of li.e Sciences Chongqing UniversityChongqingChina

Circular RnAs(circRnAs)are a class of covalently closed single-stranded RnAs that are expressed during the development of specific cells and *** play crucial roles in physiological and pathological processes by sponging microRnAs,modulating gene transcription,controlli.g the activity of certain RnA-binding proteins,and producing functional peptides.A key focus of research at present is the functionali.y of circRnAs in the nervous system and several advances have emerged over the last 2 ***,the precise role of circRnAs in the nervous system has yet to be comprehensively *** this review,we first summarize the recently described roles of circRnAs in brain development,maturity,and ***,we focus on the involvement of circRnAs in various diseases of the central nervous system,such as brain cancer,chronic neurodegenerative diseases,acute injuries of the nervous system,and neuropathic pain.A better understanding of the functionali.y of circRnAs will help us to develop potential diagnostic,prognostic,and therapeutic strategies to treat diseases of the nervous system.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis brain development circRnAs neuropathic pain Parkinson’s disease

interface structure of α-Mg/14H-LPSO:First-principles prediction and experimental study

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Journal of Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： Yuan shi Xiaohua Zhang Hongyan Yue Chao li School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

The interfacial structure of the α-Mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSTEM) imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(Terl-MgY-hollow,Ter2-Zn-hollow,Ter3-MgYii-hollow and Ter4-Mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-MgY-hollow and Ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV ing change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m^(2) for the interface model of α-Mg and 14H-LPSO phase structure with Ter2-Zn-hollow termination.

关键词： Rare earths Magnesium alloy HAADF-STEM LPSO First-principles interface

Supercritical CO_(2) Cycles for nuclear-Powered Marine Propulsion:Preli.inary Conceptual Design and Off-Design Performance Assessment

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Journal of Thermal Science 2024年第1期33卷 328-347页

作者： li.Zhaozhi shi Mingzhu SHAO Yingjuan ZHOnG Wenqi Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Using the efficient,space-saving,and flexible supercritical carbon dioxide(sCO_(2)) Brayton cycle is a promising approach for improving the performance of nuclear-powered *** purpose of this paper is to design and compare sCO_(2) cycle power systems suitable for nuclear-powered *** the characteristics of nuclear-powered ships,this paper uses different indicators to comprehensively evaluate the efficiency,cost,volume,and partial load performance of several nuclear-powered sCO_(2) *** load-following strategies are also designed and *** results show that the partial cooli.g cycle is most suitable for nuclear-powered ships because it offers both high thermal efficiency and low volume and cost,and can maintain relatively high thermal efficiency at partial ***,the new load-following strategy that adjusts the turbine speed can keep the compressor away from the surge li.e,making the cycle more flexible and efficient compared to traditional inventory and turbine bypass strategies.

关键词： supercritical CO_(2)cycle nuclear marine propulsion off-design performance

Efficient unequal error protection for onli.e fountain codes

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Journal of Systems Engineering and Electronics 2024年第2期35卷 286-293页

作者： shi Pengcheng WAnG Zhenyong li.Dezhi LYU Haibo School of Electronics and information Engineering Harbin Institute of TechnologyHarbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China

in this paper,an efficient unequal error protection(UEP)scheme for onli.e fountain codes is *** the buildup phase,the traversing-selection strategy is proposed to select the most important symbols(MiS).Then,in the completion phase,the weighted-selection strategy is appli.d to provide low *** performance of the proposed scheme is analyzed and compared with the existing UEP onli.e fountain *** results show that in terms of MiS and the least important symbols(li.),when the bit error ratio is 10-4,the proposed scheme can achieve 85%and 31.58%overhead reduction,respectively.

关键词： onli.e fountain code random graph unequal error protection(UEP) rateless code