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Nano Research 2024年第1期17卷 407-415页

作者： yumei ma Lijie Zhang Kang Zhu Binze Zhang Ranran Peng Changrong Xia Ling Huang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046China Department of materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Promoting the oxygen reduction reaction(ORR)is critical for commercialization of intermediate-temperature solid oxide fuel cells(IT-SOFCs),where Sr_(2)Fe_(1.5)Mo_(0.5)O_(6)−δ(SFM)is a promising cathode by working as a mixed ionic and electronic *** this work,doping of In^(3+)greatly increases the oxygen vacancy concentration and the content of adsorbed oxygen species in Sr_(2)Fe_(1.5)Mo_(0.5−x)InxO_(6−δ)(SFMInx),and thus effectively promotes the ORR *** a typical example,SFMIn_(0.1)reduces the polarization resistance(R_(p))from 0.089 to 0.046Ω∙cm^(2)at 800°C,which is superior to those doped with other metal *** addition,SFMIn0.1 increases the peak power density from 0.92 to 1.47 W∙cm^(−2)at 800°C with humidified H_(2)as the fuel,indicating that In3+doping at the Mo site can effectively improve the performance of SOFC cathode material.

关键词： solid oxide fuel cell cathode In3+doping oxygen reduction reaction(ORR) Sr_(2)Fe_(1.5)Mo_(0.5)O_(6-δ)

基于联邦学习的无线通信网络DoS攻击检测方法

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现代电子技术 2024年第18期47卷 47-51页

作者：马玉梅张东阳华北电力大学(保定)计算机系河北保定071003

无线通信网络受到DoS攻击,会使得网络的负载增加,导致延迟增加。而在无线通信网络中,数据通常分散在多个节点上,这会造成数据泄露和被攻击。为此,提出一种基于联邦学习的无线通信网络DoS攻击检测方法。对初始无线通信网络数据进行预处... 详细信息

无线通信网络受到DoS攻击,会使得网络的负载增加,导致延迟增加。而在无线通信网络中,数据通常分散在多个节点上,这会造成数据泄露和被攻击。为此,提出一种基于联邦学习的无线通信网络DoS攻击检测方法。对初始无线通信网络数据进行预处理和归一化,并采用随机森林算法进行降维处理,去除冗余特征,获得最佳网络数据特征集。将特征集输入到以深度卷积神经网络为通用模型的联邦学习训练模型中,独立训练本地模型并进行模型修正,传输至中心服务器进行聚合,收敛后完成训练。利用训练得到的联邦学习模型检测无线通信网络DoS攻击速率,再与接收者接收的容量最大值进行比较,判断是否有DoS攻击。实验结果表明,所提方法在处理大量数据时具有较高的稳定性和可靠性,能够在短时间内准确地检测出DoS攻击。

关键词：联邦学习无线通信网络 DoS攻击检测深度卷积神经网络随机森林算法通用模型

“双碳目标”下中国乳业财务绩效评价研究——以伊利集团为例

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中国乳业 2024年第1期 22-27页

作者：马玉梅兰州财经大学甘肃兰州730030

“双碳目标”的提出使各大行业纷纷步入转型浪潮,于是低碳环保、节能减排措施后形成的财务绩效水平成为企业较关注的问题。本文以中国乳业中具有代表性的伊利集团为研究对象,对其财务指标按照熵权法确定权重后再分析和ESG评价体系法进... 详细信息

“双碳目标”的提出使各大行业纷纷步入转型浪潮,于是低碳环保、节能减排措施后形成的财务绩效水平成为企业较关注的问题。本文以中国乳业中具有代表性的伊利集团为研究对象,对其财务指标按照熵权法确定权重后再分析和ESG评价体系法进行双重分析,最终总结了该企业提升绩效水平的措施,给中国乳业以启示。

关键词：双碳目标熵权法财务绩效

Research on Image Signal Identification Based on Adaptive Array Stochastic Resonance

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Journal of Systems Science & Complexity 2022年第1期35卷 179-193页

作者： ZHAO Jingjing ma yumei PAN Zhenkuan ZHANG Huage College of Computer Science&Technology Qingdao UniversityQingdao 266071China.

Aiming at the problems of low accuracy of image signal identification and poor anti-noise signal interference ability under strong noise environment,a signal identification method of correlated noisy image based on adaptive array stochastic resonance(SR)is proposed in this ***,the two-dimensional grayscale image is transformed to a one-dimensional binary pulse amplitude modulation(BPAM)signal with periodicity by the row or column scanning method,encoding and ***,the one-dimensional low signal-to-noise ratio BPAM signal can be applied to the saturating nonlinearity array SR module for image signal identification processing and part of the noise energy is converted into signal ***,the one-dimensional image signal processed by the nonlinearities is demodulated,decoded and reverse scanned to get the restored grayscale *** simulation results show that the image signal identification method proposed in this paper is highly efficient and accurate for the identification of noisy image signals of different sizes,and the bit error rate(BER)is also significantly reduced.

关键词： Array stochastic resonance bit error rate image restoration saturating nonlinearity signal identification

Barrier Lyapunov Function-Based Finite-Time Dynamic Surface Control for Output-Constrained Nonstrict-Feedback Systems

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Journal of Systems Science & Complexity 2023年第2期36卷 524-539页

作者： YU Jinpeng FU Cheng LIU Jiapeng ma yumei The College of Automation Qingdao UniversityQingdao 266003China Shandong Key Laboratory of Industrial Control Technology Qingdao UniversityQingdao 266003China The School of Control Science and Engineering Shandong UniversityJinan 250100China

This paper investigates a finite-time tracking problem for the uncertainty nonlinear systems in nonstrict-feedback form,in which the output signal is restricted in a *** on the barrier Lyapunov function and dynamic surface control scheme,a novel adaptive neural controller is proposed by using the finite-time Lyapunov *** the aforementioned literature on finite time tracking control,the violation of system output constraint is avoided by combining the barrier Lyapunov function method with finite-time *** structural characteristics of neural network is introduced to expand the adaptive neural finite-time backstepping method to the uncertainty nonlinear systems in the non-strict ***,the dynamic surface control is introduced to cope with the problem of“explosion of complexity”inherent in conventional backstepping *** is shown that the designed controller can achieve finite-time tracking control and all the variables in the closed-loop system are bounded with output constraint guaranteed form stability analysis and simulation results.

关键词： Adaptive neural network control explosion of complexity finite-time tracking nonstrictfeedback form

Identification for the Low-Contrast Image Signal with Regularized Variational Term and Dynamical Saturating Nonlinearity

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Journal of Systems Science & Complexity 2023年第3期36卷 1089-1102页

作者： ZHANG Ning ma yumei PAN Zhenkuan HUANG Baoxiang WANG Dongcheng College of Computer Science&Technology Qingdao UniversityQingdao 266071China

In recent years,image processing based on stochastic resonance(SR)has received more and more *** this paper,a new model combining dynamical saturating nonlinearity with regularized variational term for enhancement of low contrast image is *** regularized variational term can be setting to total variation(TV),second order total generalized variation(TGV)and non-local means(NLM)in order to gradually suppress noise in the process of solving the *** addition,the new model is tested on a mass of gray-scale images from standard test image and low contrast indoor color images from Low-Light dataset(LOL).By comparing the new model and other traditional image enhancement models,the results demonstrate the enhanced image not only obtain good perceptual quality but also get more excellent value of evaluation index compared with some previous methods.

关键词： Dynamical saturating nonlinearity image enhancement low contrast regularized variational term stochastic resonance(SR)

Transient Characteristics and Quantitative Analysis of Electromotive Force for DFIG-based Wind Turbines during Grid Faults

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Chinese Journal of Electrical Engineering 2022年第2期8卷 3-12页

作者： yumei ma Donghai Zhu Xudong Zou Yong Kang Josep M.Guerrero Key Laboratory of Power Electronics and Energy management for Ministry of Education of China Huazhong University of Science and TechnologyWuhan 430074China Department of Energy Technology Aalborg UniversityAalborg 9220Denmark

For doubly-fed induction generator(DFIG)-based wind turbines(WTs),various advanced control schemes have been proposed to achieve the low voltage ride through(LVRT)capability,whose parameters design is significantly reliant on the rotor electromotive force(EMF)of DFIG-based ***,the influence of the rotor current on EMF is usually ignored in existing studies,which cannot fully reflect the transient characteristics of *** tackle with this issue,this study presents a comprehensive and quantitative analysis of EMF during grid faults considering various control ***,the DFIG model under grid faults is ***,the transient characteristics of EMF are analyzed under different control modes(that is,rotor open-circuit and connected to converter).Furthermore,the EMF transient eigenvolumes(that is,accessorial resistance item,transient decay time constant,and frequency offset)are quantitatively analyzed with the typical parameters of MW-level DFIG-based *** analysis results contribute to the design of the LVRT control ***,the analysis is validated by the hardware-in-the-loop experiments.

关键词： Doubly-fed induction generator(DFIG) electromotive force(EMF) quantitative analysis transient characteristics wind turbines(WTs) grid faults

Peaked abundance of Calanus sinicus earlier shifted in the Changjiang River (Yangtze River) Estuary:a comparable study between 1959,2002 and 2005

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Acta Oceanologica Sinica 2011年第3期30卷 84-91页

作者： XU Zhaoli ma Zengling WU yumei Key and Open Laboratory of marine and Estuary Fisheries （Ministry of Agriculture） East China Sea Fisheries Research Institute Chinese Academy of Fisheries Science Shanghai 200090 China

The sea surface temperature （SST） of the East China Sea （ECS） increased in the past decades, which may have a great impact on the ecosystem of the ECS, including the changes in planktonpopulation structure. In this paper, the changes in peaked abundance of Calanus sinicus in the Changjiang River （Yangtze River） Estuary were compared between 1959 and 2002, based on the data collected from the seasonally oceanographic cruises and those performed in spring of 2005. It was much higher in spring compared with that in other seasons both in 1959 and 2002. Furthermore, in spring 2005, the time for occurrence and decrease of the peaked C. sinicus abundance advanced about one month, accompanying the increase in the sea surface water temperature （SST）. It peaked in June and decreased in July in 1959, however, in 2005, it peaked in may and attenuated sharply in early June. The earlier decrease of peaked C. sinicus abundance may further deteriorate the ecosystem in the Changjiang River Estuary and north nearshore of the ECS.

关键词： Calanus sinicus East China Sea (ECS) temperature Changjiang River (Yangtze River) Estuary zooplankton

富硒土地开发利用评价体系的建立及应用——以西安市临潼区为例

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中国地质 2024年第2期51卷 676-688页

作者：任蕊晁旭张立君支倩徐翠玲凌丹丹马宇梅陈继平乔新星杜少喜陕西省水工环地质调查中心陕西西安710068 陕西省地质调查规划研究中心(陕西省地质勘查基金中心) 陕西西安710068 中国富硒产业研究院陕西安康725000 长安大学地质工程与测绘学院陕西西安710054

【研究目的】人体日常摄入的硒主要通过食物链源于土壤,而中国是富硒土地资源相对匮乏的国家,面对有限且珍贵的富硒土地资源,亟需构建科学合理的富硒土地开发利用评价体系,为特色土地资源的高效开发提供依据。【研究方法】本文以陕西关... 详细信息

【研究目的】人体日常摄入的硒主要通过食物链源于土壤,而中国是富硒土地资源相对匮乏的国家,面对有限且珍贵的富硒土地资源,亟需构建科学合理的富硒土地开发利用评价体系,为特色土地资源的高效开发提供依据。【研究方法】本文以陕西关中地区为研究区,在土地质量地球化学调查成果基础上,融合反映农用地自然条件、基础设施水平的评价指标,构建了涵盖立地条件、土壤硒含量、理化性质、土壤质量和土地管理等5大类12项指标的关中地区富硒土地开发利用评价体系。同时以西安市临潼区为例,开展了临潼区富硒土地开发利用适宜性评价。【研究结果】将临潼区土地划分为高度适宜区、适宜区、较不适宜区、不适宜区和极不适宜区共5个等级,其中高度适宜开发区及适宜区开发面积共248.35 km^(2),主要分布在临潼区北部的新市乡、栎阳镇、徐杨乡、相桥镇及中东部的何寨镇。基于不同适宜评价区内小麦硒含量及富硒比例,发现其富硒土地适宜性与小麦富硒程度高度耦合。【结论】说明构建的富硒土地开发利用评价体系对富硒土地资源的开发利用具有较好的科学指导价值及重要的示范意义。

关键词：富硒土地开发利用评价体系农业地质调查工程临潼区关中地区

THE ALEKSANDROV PROBLEM FOR UNIT DISTANCE PRESERVING maPPING

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Acta mathematica Scientia 2000年第3期20卷 359-364页

作者：马玉梅 Department of mathematics Dalian University Dalian 116622 China

In this paper, one of the Aleksandrov problem was resolved, the proof that a mapping f which preserve unit distance between two real p-normed spaces X and Y is an isometry if Y is a p-strictly convex space and f satisfies locally Lipschitz condition was shown, and a same result in normed spaces was given. In addition, a proof which there doesn't exist any isometry between some spaces was obtained.

关键词： isometry p-normed space Dopp