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中国烟草机械化研究现状、热点与展望——基于CiteSpace可视化分析

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中国农机化学报 2025年第1期46卷 282-289页

作者：郑乐刘新源宋正熊梁鹏飞王玉洁贵州大学机械工程学院贵阳市550025 河南省烟草公司三门峡市公司烟叶生产技术中心河南三门峡472000 河南省烟草公司洛阳市烟草公司嵩县分公司河南洛阳471000 河南省烟草公司洛阳市公司烟叶生产技术中心河南洛阳471000

为探究中国烟草机械化发展现状、研究趋势和前沿领域,借助数据可视化软件CiteSpace,对中国知网自2000年以来所收录的有关烟草机械化的1 949条文献作为样本数据进行发文数量、研究人员、研究单位、研究领域和研究热点等方面的可视化分析... 详细信息

为探究中国烟草机械化发展现状、研究趋势和前沿领域,借助数据可视化软件CiteSpace,对中国知网自2000年以来所收录的有关烟草机械化的1 949条文献作为样本数据进行发文数量、研究人员、研究单位、研究领域和研究热点等方面的可视化分析。各项数据分析显示国内烟草机械化研究在稳步发展,同时仍然存在一些问题。研究表明,我国烟草机械化学术研究在时间线上呈现出初步探索、迅速发展和波动下降3个阶段;论文作者和科研机构之间的合作程度较低,合作密度仅为0.001 8,目前尚未形成强有力的核心研究团队;研究热点由烟草生产、增产逐步向集成化、专业化演进,现阶段的研究热点不仅仅局限于传统的增收增产,而是聚焦于烟叶的视觉识别。因此,深度聚焦学科交叉融合,多元化发展,同时推动建立农机农艺融合体系,组合优化农业机械、农业技术和作业工艺,使农艺与农机组成有机生产作业系统,建立现代烟草农业生态。

关键词：烟草可视化知识图谱聚类分析 CiteSpace

Dynamic Frequency Support and DC Voltage Regulation Approach for VSC-MTDC Systems

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 645-658页

作者： Chongru Liu Haoyu Liu Siwen Jiang le zheng State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

When an additional frequency control is implemented in the voltage source converter-based multi-terminal high voltage direct current(VSC-MTDC)system,the DC grid is capable of responding to a frequency disturbance in the AC ***,the original additional frequency control may cause the DC voltage to exceed the limit when providing power for a severe frequency disturbance,threatening the security of the DC system.A novel dynamic additional frequency control strategy for the VSC-MTDC system is developed based on the relationship between the DC voltage and the frequency droop coefficient.A dynamic frequency droop coefficient is designed to adaptively adjust the support power of the DC grid,balancing the frequency regulation of the disturbed AC system and the voltage stability of the DC grid.A DC voltage recovery method based on multi-converter cooperation is proposed to cope with the DC voltage deviation caused by the additional frequency *** validate the advantages and satisfactory performance of the proposed method during power disturbances with different severities and for the process of DC voltage recovery.

关键词： Additional frequency control DC voltage recovery module dynamic frequency droop coefficient VSCMTDC

Regularity for P-Harmonic Type Systems with the Gradients below the Controllable Growth

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1757-1766页

作者： Shen Zhou zheng Shu le ZHAO Department of Mathematics Beijing Jiaotong University Beijing 100044 P. R. China

In this paper, we shall establish that each weak solution of p-harmonic type systems with the gradients below the controllable growth belongs to, Holder continuity spaces with any HSlder exponent α∈ [0, 1）. Furthermore, we can obtain that the gradients of the corresponding weak solutions also belong to locally Hoelder continuity spaces with some Hoelder exponent. Keywords controllable growth, p-harmonic systems, full regularity MR（2000） Subject Classification 35J60, 35B65

关键词： controllable growth p-harmonic systems full regularity

基于ABC-X理论的护理干预在慢性创面患者A-ADM治疗中的应用效果

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临床心身疾病杂志 2025年第1期31卷 142-147页

作者：梅利源张成书郑乐平煤神马医疗集团总医院河南平顶山467000

目的探究基于ABC-X理论的护理干预在慢性创面患者异体脱细胞真皮基质(A-ADM)治疗中的应用效果。方法将80例慢性创面患者根据入院时间分为对照组(37例)和观察组(43例)。两组患者均接受A-ADM治疗及常规护理干预,观察组患者在此基础上接受... 详细信息

目的探究基于ABC-X理论的护理干预在慢性创面患者异体脱细胞真皮基质(A-ADM)治疗中的应用效果。方法将80例慢性创面患者根据入院时间分为对照组(37例)和观察组(43例)。两组患者均接受A-ADM治疗及常规护理干预,观察组患者在此基础上接受基于ABC-X理论的护理干预。比较两组患者创面水肿情况、愈合情况及手术前后负性情绪、疾病不确定感、应对方式变化。结果两组患者术后24 h、48 h创面水肿评分,术后1周、2周创面愈合率及创面愈合时间比较,差异均无统计学意义(P>0.05)。术后2周,两组患者焦虑自评量表、抑郁自评量表评分较术前降低,且观察组低于对照组(P0.05)。术后2周,两组患者简易应对方式问卷的积极应对维度评分较术前升高,消极应对维度评分较术前降低,且观察组优于对照组(P<0.05或0.01)。结论在慢性创面患者A-ADM治疗中应用基于ABC-X理论的护理干预,有利于改善患者的负性情绪、疾病不确定感及应对方式,促进患者早日康复,应用效果良好。

关键词：慢性创面异体脱细胞真皮基质 ABC-X理论护理干预负性情绪疾病不确定感应对方式

Active splitting strategy searching approach based on MISOCP with consideration of power island stability

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Journal of Modern Power Systems and Clean Energy 2019年第3期7卷 475-490页

作者： Yifan ZHOU Wei HU Yong MIN le zheng Department of Electrical Engineering Tsinghua UniversityBeijing100084China Department of Cardiothoracic Surgery Stanford UniversityStanfordUSA

Active splitting control utilizes real-time decision and system-level splitting to prevent cascading blackouts and to maintain power supply under severe disturbances. Splitting strategy searching(SSS) is one of the most crucial issues in active splitting control for deciding‘‘where to split’’. SSS determines the splitting surface in real time to properly divide the asynchronous generators into isolated islands with an optimal control effect. In this paper, an SSS approach that focuses on island stability is presented. The proposed SSS approach is designed to ensure a rational stability margin and regulation ability on each island during and after the transient process of system splitting. This method includes the active/reactive power flow feasibility constraints and voltage/angle stability constraints in the steady state as well as the frequencyresponse capability constraints in the transient process. By considering the island stability constraints in the SSS, the proposed approach can avoid the splitting strategies with poor stability performance. Therefore, the major advantage of the proposed approach is that it can ensure better island static and transient stability during and after the splitting control. In addition, the entire model is formulated as a mixed-integer second-order cone programming(MISOCP)model. Thus, it can be rapidly solved by using commercial optimization solvers. Numerical simulations of a realistic provincial power system in central China demonstrate thevalidity of the proposed approach and the necessity of considering the island stability issues.

关键词： Splitting strategy searching(SSS) Mixed-integer second-order cone programming(MISOCP) Controlled islanding Static stability margin Transient stability Power system

Improved Deep Belief Network and Model Interpretation Method for Power System Transient Stability Assessment

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 27-37页

作者： Shuang Wu le zheng Wei Hu Rui Yu Baisi Liu State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Stanford University StanfordCalifornia 94305USA Southwest Branch State Grid Corporation of ChinaChengdu 610041China

The real-time transient stability assessment(TSA)and emergency control are effective measures to suppress accident expansion,prevent system instability,and avoid large-scale power outages in the event of power system ***,real-time assessment is extremely demanding on computing speed,and the traditional method is not *** this paper,an improved deep belief network(DBN)is proposed for the fast assessment of transient stability,which considers the structural characteristics of power system in the construction of loss *** learning has been effective in many fields,but usually is considered as a black-box *** the perspective of machine learning interpretation,this paper proposes a local linear interpreter(LLI)model,and tries to give a reasonable interpretation of the relationship between the system features and the assessment result,and illustrates the conversion process from the input feature space to the high-dimension representation *** proposed method is tested on an IEEE new England test system and demonstrated on a regional power system in *** result demonstrates that the proposed method has rapidity,high accuracy and good interpretability in transient stability assessment.

关键词： Transient stability assessment(TSA) representation learning deep belief network(DBN) local linear interpretation(LLI) visualization emergency control

Data-driven Estimation for a Region of Attraction for Transient Stability Using the Koopman Operator

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1405-1413页

作者： le zheng Xin Liu Yanhui Xu Wei Hu Chongru Liu the School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

This paper presents a novel Koopman Operator based framework to estimate the region of attraction for power system transient stability *** Koopman eigenfunctions are used to numerically construct a Lyapunov *** the level set of the function is utilized to estimate the boundary of the region of *** method provides a systematic method to construct the Lyapunov function with data sampled from the state space,which suits any power system models and is easy to use compared to traditional Lyapunov direct *** addition,the constructed Lyapunov function can capture the geometric properties of the region of attraction,thus providing useful information about the instability *** method has been verified by a simple illustrative example and three power system models,including a voltage source converter interfaced system to analyze the large signal synchronizing instability induced by the phase lock loop *** proposed method provides an alternative approach to understanding the geometric properties and estimating the boundary of the region of attraction of power systems in a data driven *** Terms-Koopman operator,lyapunov function,power system transient stability,region of attraction.

关键词： Koopman operator lyapunov function power system transient stability region of attraction.

Simulation of Far-Field Superresolution Fluorescence Imaging with Two-Color One-Photon Excitation of Reversible Photoactivatable Protein

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Chinese Physics letters 2011年第5期28卷 136-139页

作者： WANG Chen QIAO Ling-Ling MAO zheng-le State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

We propose to achieve far-field super-resolution imaging by using offset two-color one-photon(2C1P)excitation of reversible photoactivatable fluorescence *** to the distinctive photoswitching performance of the proteins,such as dronpa,the fluorescence emission will only come from the overlapped region of activation beam and excitation *** analysis solution of rate equation shows that the resolution of offset 2C1P microscope is"engineered"by laser power of excitation and activation beams and the power ratio between *** lateral and transverse resolution is theoretically demonstrated compared with conventional fluorescence scanning microscopy.

关键词： excitation activation resolution

A radar waveform bandwidth selection strategy for wideband tracking

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Science China(Information Sciences) 2019年第4期62卷 50-52页

作者： Shaoqiang CHANG Honggang ZHANG Teng LONG Quanhua LIU le zheng Radar Research Laboratory School of Information and Electronics Beijing Institute of Technology Department of Electronic Engineering Tsinghua University Key Laboratory of Electronic and Information Technology in Satellite Navigation (Beijing Institute of Technology) Ministry of Education Electrical Engineering Department Columbia University

Dear editor,The performance of radar target detection and tracking is greatly influenced by waveform bandwidth. Ref. [1] proposes that very narrowband waveforms are usually employed for search, narrowband waveforms ar... 详细信息

关键词： A radar waveform bandwidth selection strategy for wideband tracking KT