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基于制造商生产成本扰动的不同主导权下供应链脆弱性研究

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工业工程 2021年第6期24卷 123-131,149页

作者：张萌萌闫秀霞董友衡山东理工大学管理学院山东淄博255000

为了定量研究生产成本扰动和不同权利结构下的供应链脆弱性,分别构建集中决策、制造商主导和零售商主导的线上线下双渠道供应链和直销供应链两种供应链博弈模型。采用使供应链最优决策保持不变的制造商生产成本扰动区间长度来衡量供应... 详细信息

为了定量研究生产成本扰动和不同权利结构下的供应链脆弱性,分别构建集中决策、制造商主导和零售商主导的线上线下双渠道供应链和直销供应链两种供应链博弈模型。采用使供应链最优决策保持不变的制造商生产成本扰动区间长度来衡量供应链脆弱性的大小,区间长度越大,供应链脆弱性越小。结果表明:1)对线上线下双渠道供应链而言,集中决策和制造商主导时的成本扰动区间长度相等,即脆弱性相同,且大于零售商主导时的脆弱性;2)对直销供应链而言,制造商主导时的成本扰动区间长度大于集中决策时的区间长度,即制造商主导时的供应链脆弱性小于集中决策时的脆弱性,而零售商主导时脆弱性的大小与参数β、k有关。最后通过数值仿真验证了该方法的可行性。

关键词：供应链脆弱性博弈论权力结构成本扰动

Potential reduction in carbon fixation capacity under climate change in a Pinus koraiensis forest

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Forest Ecosystems 2024年第2期11卷 152-161页

作者： dong Kook Woo Department of Civil Engineering Keimyung UniversityDaegu42601Republic of Korea

There has been an increasing recognition of the crucial role of forests, responsible for sequestering atmospheric CO_(2), as a moral imperative for mitigating the pace of climate change. The complexity of evaluating climate change impacts on forest carbon and water dynamics lies in the diverse acclimations of forests to changing environments. In this study, we assessed two of the most common acclimation traits, namely leaf area index and the maximum rate of carboxylation(V_(cmax)), to explore the potential acclimation pathways of Pinus koraiensis under climate change. We used a mechanistic and process-based ecohydrological model applied to a P. koraiensis forest in Mt. Taehwa, South Korea. We conducted numerical investigations into the impacts of(i) Shared Socioeconomic Pathways 2–4.5(SSP2-4.5) and 5–8.5(SSP5-8.5),(ii) elevated atmospheric CO_(2) and temperature, and(iii) acclimations of leaf area index and V_(cmax)on the carbon and water dynamics of P. koraiensis. We found that there was a reduction in net primary productivity(NPP) under the SSP2-4.5 scenario, but not under SSP5-8.5, compared to the baseline, due to an imbalance between increases in atmospheric CO_(2) and temperature. A decrease in leaf area index and an increase in V_(cmax)of P. koraiensis were expected if acclimations were made to reduce its leaf temperature. Under such acclimation pathways, it would be expected that the well-known CO_(2) fertilizer effects on NPP would be attenuated.

关键词： Climate change NEP Pinus koraiensis Warming Acclimation

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新型一维偏移耦合映像格系统及其动态特性

计算机应用研究 2023年第11期40卷 3289-3293,3302页

作者：赵耿潘周马英杰董有恒北京电子科技学院网络空间安全系北京100070 北京邮电大学网络空间安全学院北京100089

混沌系统具有复杂的动力学行为,但在数字系统中运行时会出现动力学特性退化的问题。元胞自动机在时间、空间上都具有离散性,能够有效减弱混沌系统在有限精度下的动力学退化问题。基于元胞自动机,提出了一种一维偏移耦合映像格系统,利用... 详细信息

混沌系统具有复杂的动力学行为,但在数字系统中运行时会出现动力学特性退化的问题。元胞自动机在时间、空间上都具有离散性,能够有效减弱混沌系统在有限精度下的动力学退化问题。基于元胞自动机,提出了一种一维偏移耦合映像格系统,利用初等元胞自动机每次更新的不同状态,动态产生每个格子的耦合索引偏移量,再根据偏移量对混沌序列施加不同的扰动,然后交替切换元胞自动机的迭代规则。最后,对混沌系统的动力学特性进行对比分析以及对该系统产生的时间序列进行量化和随机性检测,仿真实验结果表明,该混沌系统周期更长,遍历性更好,产生的序列随机性更佳,在序列密码算法中有很大的应用价值。

关键词：混沌元胞自动机耦合映像格子序列密码 Lyapunov指数

基于抗退化混沌系统和初等元胞自动机的动态S盒设计

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计算机科学 2023年第11期50卷 333-339页

作者：赵耿高世蕊马英杰董有恒北京电子科技学院网络空间安全系北京100071 北京邮电大学网络空间安全学院北京100089

S盒是多数分组密码算法的基本非线性模块,可以满足分组密码算法的混淆、扩散要求。为了提高混沌S盒的安全性,文中利用抗退化混沌系统生成S盒元素,基于初等元胞自动机生成S盒检索表的方式来生成S盒。抗退化混沌系统可以避免发生Skew Ten... 详细信息

S盒是多数分组密码算法的基本非线性模块,可以满足分组密码算法的混淆、扩散要求。为了提高混沌S盒的安全性,文中利用抗退化混沌系统生成S盒元素,基于初等元胞自动机生成S盒检索表的方式来生成S盒。抗退化混沌系统可以避免发生Skew Tent系统进入不动点的情况,消除低精度下系统进入短周期的现象。因为初等元胞自动机的迭代规则为二元域上的运算,且满足时空上的离散性,所以,将初等元胞自动机运用到混沌分组密码中时,不用考虑动力学退化的问题。当初等元胞自动机的迭代规则为全局混沌规则时,只要元胞个数足够,就可以保证输出的伪随机性。利用初等元胞自动机生成S盒的检索表,在保证S盒设计的混淆原则的同时还可以简化S盒的生成步骤。最后对所设计的S盒进行安全性分析对比,实验结果表明,所提方法生成的S盒具有良好的安全性,满足分组密码的混淆、扩散原则,可用于混沌分组密码算法设计中。

关键词： S盒抗退化混沌初等元胞自动机 Lorenz系统 Skew Tent系统

Internal Polarization Field Induced Hydroxyl Spillover Effect for Industrial Water Splitting Electrolyzers

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Nano-Micro Letters 2024年第2期16卷 438-449页

作者： Jingyi Xie Fuli Wang Yanan Zhou Yiwen dong Yongming Chai Bin dong State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580People’s Republic of China

The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction(OER)are affinitive with hydroxyl ***,ability of the catalyst to capture hydroxyl and maintain the continuous supply at active sits remains a tremendous ***,an affordable Ni2P/FeP2 heterostructure is presented to form the internal polarization field(IPF),arising hydroxyl spillover(HOSo)during *** by IPF,the oriented HOSo from FeP2 to Ni2P can activate the Ni site with a new hydroxyl transmission channel and build the optimized reaction path of oxygen intermediates for lower adsorption energy,boosting the OER activity(242 mV *** at 100 mA cm-2)for least 100 *** interestingly,for the anion exchange membrane water electrolyzer(AEMWE)with low concentration electrolyte,the advantage of HOSo effect is significantly amplified,delivering 1 A cm^(-2)at a low cell voltage of 1.88 V with excellent stability for over 50 h.

关键词： Hydroxyl spillover effect Internal polarization field Heterostructure Oxygen reduction reaction Anion exchange membrane water electrolysis

Improved Approximation Schemes for Early Work Scheduling on Identical Parallel Machines with a Common Due Date

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Journal of the Operations Research Society of China 2024年第2期12卷 341-350页

作者： Wei-dong Li School of Mathematics and Statistics Yunnan UniversityKunming650504YunnanChina

We study the early work scheduling problem on identical parallel machines in order to maximize the total early work,i.e.,the parts of non-preemptive jobs that are executed before a common due *** preprocessing and constructing an auxiliary instance which has several good properties,for any desired accuracy,we propose an efficient polynomial time approximation scheme with running time O(f(1/ε)n),where n is the number of jobs and f(1/ε)is exponential in 1/ε,and a fully polynomial time approximation scheme with running time O(1/ε^(2m+1)+n)when the number of machines is fixed.

关键词： Scheduling Early work Polynomial time approximation scheme Effcient polynomial time approximation scheme Fully polynomial time approximation scheme

A Long-Time-Step-Permitting Tracer Transport Model on the Regular Latitude–Longitude Grid

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Advances in Atmospheric Sciences 2024年第3期41卷 493-508页

作者： Jianghao LI Li dong Key Laboratory of Earth System Modeling and Prediction China Meteorological AdministrationBeijing 100081China State key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather(LaSW) Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

If an explicit time scheme is used in a numerical model, the size of the integration time step is typically limited by the spatial resolution. This study develops a regular latitude–longitude grid-based global three-dimensional tracer transport model that is computationally stable at large time-step sizes. The tracer model employs a finite-volume flux-form semiLagrangian transport scheme in the horizontal and an adaptively implicit algorithm in the vertical. The horizontal and vertical solvers are coupled via a straightforward operator-splitting technique. Both the finite-volume scheme's onedimensional slope-limiter and the adaptively implicit vertical solver's first-order upwind scheme enforce monotonicity. The tracer model permits a large time-step size and is inherently conservative and monotonic. Idealized advection test cases demonstrate that the three-dimensional transport model performs very well in terms of accuracy, stability, and efficiency. It is possible to use this robust transport model in a global atmospheric dynamical core.

关键词： tracer transport numerical stability latitude–longitude grid

CONVERGENCE ANALYSIS OF SOME FINITE ELEMENT PARALLEL ALGORITHMS FOR THE STATIONARY INCOMPRESSIBLE MHD EQUATIONS

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Journal of Computational Mathematics 2024年第1期42卷 49-70页

作者： Xiaojing dong Yinnian He Hunan Key Laboratory for Computation and Simulation in Science and Engineering Key Laboratory of Intelligent Computing&Information Processing of Ministry of EducationSchool of Mathematics and Computational ScienceXiangtan UniversityXiangtan 411105China Institute of Applied Physics and Computational Mathematics Beijing 100088China School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China

By combination of iteration methods with the partition of unity method(PUM),some finite element parallel algorithms for the stationary incompressible magnetohydrodynamics(MHD)with different physical parameters are presented and *** algorithms are highly *** first,a global solution is obtained on a coarse grid for all approaches by one of the iteration *** parallelized residual schemes,local corrected solutions are calculated on finer meshes with overlapping *** subdomains can be achieved flexibly by a class of *** proposed algorithm is proved to be uniformly stable and ***,one numerical example is presented to confirm the theoretical findings.

关键词： Partition of unity method Local and parallel algorithm Finite element method Iteration methods Magnetohydrodynamics

Poles Extraction Based LiDAR Localization for Autonomous Robot Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1413-1424页

作者： HONG Xin dong Yi College of Electronic and Information Engineering Tongji UniversityShanghai 201800China

With the development of intelligent technology,the problem of Li DAR-based localization has played an increasingly important role in the localization of robots in unmanned *** the dense point clouds from the environment requires a large amount of memory,specific and stable structural features,such as pole-like objects in the environment,can serve as the ideal landmarks for localization in unmanned systems,which can effectively reduce the memory usage and mitigate the effects of dynamic environment *** this paper,the authors propose a pole-like objects extraction approach and then,it is applied into the localization system of mobile *** the same experimental conditions,the proposed method can extract more pole-like objects and achieve better long-term localization accuracy than some existing methods in different urban environmental datasets.

关键词： Pole-like landmark extraction robot localization