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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： Wen WANG da-peng XIE Hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality

General-purpose DNA computation

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Science China Chemistry 2024年第7期67卷 2134-2135页

作者： Junlan Liu da Han Institute of Molecular Medicine and Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Zhejiang Cancer Hospital Hangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhou 310022China

Despite the tremendous advancement in the robustness and functionality of DNA-based computing systems throughout the past decade[1-4],reconfiguration of typical DNA computing circuits for diverse tasks is still hindered by the requirement of a priori knowledge about underlying circuit *** addition,the type of algorithms that can be implemented by a DNA integrated circuit(DIC)was limited to a small number,therefore limiting the computing power of DIC[1-4].

关键词： computing knowledge limiting

Design methodology of a mini-missile considering flight performance and guidance precision

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Journal of Systems Engineering and Electronics 2024年第1期35卷 195-210页

作者： ZHANG Licong GONG Chunlin SU Hua ANDREA da Ronch Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

The design of mini-missiles(MMs)presents several novel *** stringent mission requirement to reach a target with a certain precision imposes a high guidance *** miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight *** a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC ***,a multi-objective and multidisciplinary design optimization(MDO)is *** pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO *** optimization problem seeks to maximize the range and minimize the guidance *** problem is solved by using the nondominated sorting genetic algorithm *** optimum design that balances a longer range with a smaller guidance error is ***,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach.

关键词： mini-missiles(MMs) guidance navigation and control(GNC)system multi-objective optimization multidisciplinary design optimization(MDO) flight performance guidance precision

Integrability and solutions of a nonsymmetric discrete Korteweg-de Vries equation

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Communications in Theoretical Physics 2024年第2期76卷 45-50页

作者： Maebel Mesfun da-jun Zhang Song-lin Zhao Department of Mathematics Shanghai UniversityShanghai 200444China Newtouch Center for Mathematics of Shanghai University Shanghai 200444China Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China

In this paper,we present Lax pairs and solutions for a nonsymmetric lattice equation,which is a torqued version of the lattice potential Korteweg-de Vries *** nonsymmetric equation is special in the sense that it contains only one spacing parameter but consists of two consistent cubes with other integrable lattice *** such a multidimensionally consistent property we are able to derive its two Lax pairs and also construct solutions using B?cklund transformations.

关键词： discrete Korteweg-de Vries equation nonsymmetric multi-dimensional consistency Backlund transformation solution

Regulating ion transport behaviors toward dendrite-free potassium metal batteries:recent advances and perspectives

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Rare Metals 2024年第4期43卷 1435-1460页

作者： Lu-Kang Zhao Xuan-Wen Gao Tian-Zhen Ren da Wang da-Wei Wang Zhao-Meng Liu Hong Chen Wen-Bin Luo School of Metallurgy Northeastern UniversityShenyang110819China School of Chemical Engineering The University of New South WalesSydneyNSW2052Australia

With abundant potassium resources and high capacity,potassium metal batteries(PMBs)present a compelling option for the next generation of energy storage ***,PMBs suffer from an unstable anode interface caused by uncontrolled dendrite growth,which results in unsatisfactory cyclability and safety *** investigations suggest that significant progress has been made in enhancing the interfacial stability of *** various effective strategies for stabilizing interfaces can ultimately be attributed to the regulation of the sluggish ion transfer kinetics and irregular deposition,i.e.,the arrangement of ion transport behaviors at the *** modulation of ions transport rate and ions deposition directions makes it possible to obtain a dendrite-free and smooth deposition ***,the influencing factors and action mechanism of K^(+)interface transport behaviors are discussed to understand the nature of material design for constructing stable anode interfaces,including regulating the solvation and desolvation structures,accelerating K^(+)transport kinetics and controlling K^(+)deposition *** addition,the deficiencies and prospects of the research on electrolyte,separators and designed electrode involved in the manufacturing and testing and ion transport process of PMBs are *** review is expected to provide some possible directions for constructing dendrite-free interfaces in advanced PMBs-related research and offer significant insights for prospective experimental research and commercial applications.

关键词： Ion transport rate Ion transport direction Interface Potassium metal batteries Dendrites growth

Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO

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Advances in Atmospheric Sciences 2024年第3期41卷 465-477页

作者： Xinyi XING Xianghui FANG da PANG Chaopeng JI Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction Shanghai 200438China Shanghai Key Laboratory of Ocean-land-atmosphere Boundary Dynamics and Climate Change Fudan UniversityShanghai 200438China

El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate.

关键词： SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation

Image Steganography by Pixel-Value Differencing Using General Quantization Ranges

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 353-383页

作者： da-Chun Wu Zong-Nan Shih Department of Computer and Communication Engineering National Kaohsiung University of Science and TechnologyKaohsiung824005Taiwan

A new steganographic method by pixel-value differencing(PVD)using general quantization ranges of pixel pairs’difference values is *** objective of this method is to provide a data embedding technique with a range table with range widths not limited to powers of 2,extending PVD-based methods to enhance their flexibility and data-embedding rates without changing their capabilities to resist security ***,the conventional PVD technique partitions a grayscale image into 1×2 non-overlapping *** entire range[0,255]of all possible absolute values of the pixel pairs’grayscale differences in the blocks is divided into multiple quantization *** width of each quantization range is a power of two to facilitate the direct embedding of the bit information with high embedding *** using power-of-two range widths,the embedding rates can drop using conventional embedding *** contrast,the proposed method uses general quantization range widths,and a multiple-based number conversion mechanism is employed skillfully to implement the use of nonpower-of-two range widths,with each pixel pair being employed to embed a digit in the multiple-based *** the message bits are converted into a big multiple-based number whose digits can be embedded into the pixel pairs with a higher embedding *** experimental results showed the feasibility of the proposed method and its resistance to security *** addition,implementation examples are provided,where the proposed method adopts non-power-of-two range widths and employsmultiple-based number conversion to expand the data-hiding and steganalysis-resisting capabilities of other PVD methods.

关键词： Steganography pixel-value differencing multiple-based number conversion general quantization range

Cauchy matrix approach to three non-isospectral nonlinear Schrödinger equations

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Communications in Theoretical Physics 2024年第5期76卷 1-15页

作者： Alemu Yilma Tefera Shangshuai Li da-jun Zhang Department of Mathematics Shanghai UniversityShanghai 200444China Newtouch Center for Mathematics of Shanghai University Shanghai 200444China Department of Applied Mathematics Faculty of Science and EngineeringWaseda UniversityTokyo 169-8555Japan

This paper aims to develop a direct approach,namely,the Cauchy matrix approach,to non-isospectral integrable *** the Cauchy matrix approach,the Sylvester equation plays a central role,which defines a dressed Cauchy matrix to provideτfunctions for the investigated *** this paper,using the Cauchy matrix approach,we derive three non-isospectral nonlinear Schrödinger equations and their explicit *** equations are generically related to the time-dependent spectral parameter in the Zakharov–Shabat–Ablowitz–Kaup–Newell–Segur spectral *** solutions are obtained from the solutions of unreduced non-isospectral nonlinear Schrödinger equations through complex *** solutions are analyzed and illustrated to show the non-isospectral effects in dynamics of solitons.

关键词： Cauchy matrix approach Sylvester equation nonlinear Schrödinger equation non-isospectral integrable system explicit solution

Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing Xu Sha-sha Wang da-chuan Xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

Extreme single-excitation subradiance from two-band Bloch oscillations in atomic arrays

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Photonics Research 2024年第3期12卷 571-580页

作者： LUOJIA WANG da-WEI WANG LUQI YUAN YAPING YANG XIANFENG CHEN State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Interdisciplinary Center for Quantum Information and State Key Laboratory of Modern Optical Instrumentation Zhejiang Province Key Laboratory of Quantum Technology and Deviceand School of PhysicsZhejiang UniversityHangzhou 310027China MOE Key Laboratory of Advanced Micro-Structured Materials School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

Atomic arrays provide an important quantum optical platform with photon-mediated dipole–dipole interactions that can be engineered to realize key applications in quantum information processing.A major obstacle for such applications is the fast decay of the excited *** controlling two-band Bloch oscillations of single excitation in an atomic array under an external magnetic field,here we show that exotic subradiance can be realized and maintained with orders of magnitude longer than the spontaneous decay time in atomic arrays with the finite *** key finding is to show a way for preventing the wavepacket of excited states scattering into the dissipative zone inside the free space light cone,which therefore leads to the excitation staying at a subradiant state for an extremely long decay *** show that such operation can be achieved by introducing a spatially linear potential from the external magnetic field in the atomic arrays and then manipulating interconnected two-band Bloch oscillations along opposite *** results also point out the possibility of controllable switching between superradiant and subradiant states,which leads to potential applications in quantum storage.

关键词： excitation Bloch decay