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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1217-1226页

作者： zifeng zhang Yuntao Ju State Grid Information&Telecommunication Group Co. Ltd.Beijing BranchBejingChina School of Electrical and Control Engineering North China University of TechnologyBeijingChina

Networked microgrids(NMGs)are critical in theaccommodation of distributed renewable ***,theexisting centralized state estimation(SE)cannot meet the demandsof NMGs in distributed energy *** currentestimator is also not robust against bad *** study introducesthe concepts of relative error to construct an improvedrobust SE(IRSE)optimization model with mixed-integer nonlinearprogramming(MINLP)that overcomes the disadvantage ofinaccurate results derived from different measurements whenthe same tolerance range is considered in the robust SE(RSE).To improve the computation efficiency of the IRSE optimizationmodel,the number of binary variables is reduced based on theprojection statistics and normalized residual methods,which effectivelyavoid the problem of slow convergence or divergenceof the algorithm caused by too many integer ***,an embedded consensus alternating direction of multiplier method(ADMM)distribution algorithm based on outer approximation(OA)is proposed to solve the IRSE optimization *** algorithm can accurately detect bad data and obtain SE resultsthat communicate only the boundary coupling informationwith *** tests show that the proposed algorithmeffectively detects bad data,obtains more accurate SE results,and ensures the protection of private information in all microgrids.

关键词： Distributed optimization alternating direction of multiplier methods(ADMM) robust state estimation(RSE) mixed-integer nonlinear programming(MINLP) networked microgrid(NMG)

An Improved Power Flow Method to Cope with Non-smooth Constraints of Integrated Energy Systems

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1784-1793页

作者： Yuntao Ju Jiankai Wang zifeng zhang College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China

Integrated energy system applications can significantly improve energy *** this paper,we establish an integrated energy system containing heat,electricity and *** existing power flow(PF)calculation method applied to integrated energy systems(IESs)does not consider non-smooth constraints,such as the piecewise pipeline friction coefficient and generator buses reactive power limits,*** integer nonlinear programming(MINLP)is conventionally used to deal with piecewise pipeline friction coefficients in gas network parts,but it is both complex and ***,we develop a piecewise linear function-based fitting method that can reduce the number of integer variables and enhanced the computational *** the electric network part,if the reactive power of the PV bus violates limits,it will be converted into a PQ bus,which is a non-differentiable and non-smooth *** complementarity problems are conventionally introduced to represent the PV-PQ buses type switching relationship and are addressed by the Newton-Raphson(NR)***,the above method is sensitive to the initial ***,we introduce a robust projected Levenberg-Marquardt(PLM)algorithm to cope with this *** demonstrate the advantages of our method and validate it both in a small-scale system and largescale network test cases.

关键词： Complementarity constraints integrated energy system non-smooth constraints piecewise linear function-based fitting method

Persistent organic pollutants and chemicals of emerging Arctic concern in the Arctic environment

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Environmental Science and Ecotechnology 2024年第2期18卷 1-3页

作者： Yi-Fan Li Roland Kallenborn zifeng zhang International Joint Research Center for Persistent Toxic Substances(IJRC-PTS) State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyHarbin 150090China International Joint Research Center for Arctic Environment and Ecosystem(IJRC-AEE) Polar AcademyHarbin Institute of Technology(PA-HIT)Harbin 150090China Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem(HPKL-PEE) Harbin 150090China IJRC-PTS-NA TorontoONM2J 3N8Canada Faculty of Chemistry Biotechnology and Food Sciences(KBM)Norwegian University of Life Sciences(NMBU)NOe1433 AsNorway

Environmental pollutants,such as persistent organic pollutants(POPs),enter the Arctic mainly via long-range transport(LRT)through atmospheric and ocean/river *** the other hand,chemicals of emerging Arctic concern(CEACs)are often introduced as local contaminants from industrial,municipal,or infrastructure-related *** of their origins,all these contaminants negatively impact the health of the environment and the indigenous ***,in recent decades,the Arctic has been experiencing unprecedented climate *** combination of Arctic environmental changes and the introduction of new anthropogenic contaminants as chemical aids for exploiting Arctic resources led to a severe imbalance in the Arctic ***,an international consortium of Arctic experts asked for internationally coordinated actions to mitigate the serious problems that environmental pollution causes on Arctic ecosystems and people,according to the Berlin statement[1].

关键词： Arctic statement pollution

Multispectral point cloud superpoint segmentation

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Science China(Technological Sciences) 2024年第4期67卷 1270-1281页

作者： WANG QingWang WANG MingYe zhang zifeng SONG Jian ZENG Kai SHEN Tao GU YanFeng Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Yunnan Key Laboratory of Computer Technologies Application Kunming 650500China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The multitude of airborne point clouds limits the point cloud processing *** are grouped based on similar points,which can effectively alleviate the demand for computing resources and improve processing ***,existing superpoint segmentation methods focus only on local geometric structures,resulting in inconsistent spectral features of points within a *** feature inconsistencies degrade the performance of subsequent ***,this study proposes a novel Superpoint Segmentation method that jointly utilizes spatial Geometric and Spectral Information for multispectral point cloud superpoint segmentation(GSI-SS).Specifically,a similarity metric that combines spatial geometry and spectral information is proposed to facilitate the consistency of geometric structures and object attributes within segmented *** the formation of the primary superpoints,an intersuperpoint pointexchange mechanism that maximizes feature consistency within the final superpoints is *** are conducted on two real multispectral point cloud datasets,and the proposed method achieved higher recall,precision,F score,and lower global consistency and feature classification *** experimental results demonstrate the superiority of the proposed GSI-SS over several state-of-the-art methods.

关键词： multispectral point cloud superpoint segmentation over-segmentation spatial-spectral joint metric

Using Recurrent Neural Network Structure and Multi-Head Attention with Convolution for Fraudulent Phone Text Recognition

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Computer Systems Science & Engineering 2023年第8期46卷 2277-2297页

作者： Junjie Zhou Hongkui Xu zifeng zhang Jiangkun Lu Wentao Guo Zhenye Li School of Information and Electrical Engineering Shandong Jianzhu UniversityJinan250000China

Fraud cases have been a risk in society and people’s property security has been greatly *** recent studies,many promising algorithms have been developed for social media offensive text recognition as well as sentiment *** algorithms are also suitable for fraudulent phone text *** to these tasks,the semantics of fraudulent words are more complex and more difficult to *** Neural Networks(RNN),the variants ofRNN,ConvolutionalNeuralNetworks(CNN),and hybrid neural networks to extract text features are used by most text classification ***,a single network or a simple network combination cannot obtain rich characteristic knowledge of fraudulent phone texts ***,a new model is proposed in this *** the fraudulent phone text,the knowledge that can be learned by the model includes the sequence structure of sentences,the correlation between words,the correlation of contextual semantics,the feature of keywords in sentences,*** new model combines a bidirectional Long-Short Term Memory Neural Network(BiLSTM)or a bidirectional Gate Recurrent United(BiGRU)and a Multi-Head attention mechanism module with convolution.A normalization layer is added after the output of the final hidden *** or BiGRU is used to build the encoding and decoding ***-head attention mechanism module with convolution(MHAC)enhances the ability of the model to learn global interaction information and multi-granularity local interaction information in fraudulent sentences.A fraudulent phone text dataset is produced by us in this *** THUCNews data sets and fraudulent phone text data sets are used in *** results show that compared with the baseline model,the proposed model(LMHACL)has the best experiment results in terms of Accuracy,Precision,Recall,and F1 score on the two data *** the performance indexes on fraudulent phone text data sets are all above 0.94.

关键词： BiLSTM BiGRU multi-head attention mechanism CNN

The Notch signaling pathway in retinal dysplasia and retina vascular homeostasis

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Journal of Genetics and Genomics 2010年第9期37卷 573-582页

作者： Minhua Zheng zifeng zhang Xingcheng Zhao Yuqiang Ding Hua Han Department of Medical Genetics and Developmental Biology Fourth Military Medical University Xi'an 710032 China Department of Ophthalmology Xifing Hospital Fourth Military Medical University Xi' an 710032 China Department of Anatomy and Neurobiology Tongji University School of Medicine Shanghai 200092 China

The retina is one of the most essential elements of vision pathway in vertebrate. The dysplasia of retina cause congenital blindness or vision disability in individuals, and the misbalance in adult retinal vascular homeostasis leads to neo adults, such as diabetic retinopathy or age-related macular degeneration. Many developmental signaling pathways are involved in the process of retinal development and vascular homeostasis. Among them, Notch signaling pathway has long been studied, and Notch signaling-interfered mouse models show both neural retina dysplasia and vascular abnormality. In this review, we discuss the roles of Notch signaling in the maintenance of retinal progenitor cells, specification of retinal neurons and glial cells, and the sustaining of retina vascular homeostasis, especially from the aspects of conditional knockout mouse models. The potential of Notch signal manipulation may provide a powerful cell fate- and neovascularization-controUing tool that could have important applications in treatment of retinal diseases.

关键词： Notch signaling retinal dysplasia vascular homeostasis neovascularization knockout mice

Effects of Methylprednisolone on the Expression and Activity of Calpain Following Ischemia-Reperfusion Spinal Cord Injury in Rats

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Neuroscience & Medicine 2014年第1期5卷 23-31页

作者： zifeng zhang Jinquan Xu Yushu Bai Tiesheng Hou Department of Orthopedics Shanghai Changhai Hospital Shanghai China Guanghua Integrative Medicine Hospital Changning District Shanghai China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai China

The present study was undertaken to examine the effects of methylprednisolone on the expression and activity of calpain in spinal cord tissue following spinal cord ischemia-reperfusion injury in rats. Adult male Sprague-Dawley rats were subjected to sham operations, ischemia-reperfusion and vehicle treated, or ischemia-reperfusion with methylprednisolone administration after injury. The expression of calpain I in the injured segments of the spinal cord as well as the degradation of the 68 kD neurofilament protein (NFP), a calpain-specific substrate, was determined at 3 h, 24 h, 72 h and 7 days after reperfusion using immunohistochemical labeling and western blot analysis, respectively. Three hours after spinal cord reperfusion, calpain I-positive cells and NFP degradation products were evident. The number of positive cells and immunoreactivity increased with time and peaked at 72 h after reperfusion. In addition, the number of calpain I-positive cells and the abundance of NFP degradation products were significantly lower in the methylprednisolone group, compared with vehicle treated animals following ischemia-reperfusion injury. The results of this study suggest that methylprednisolone can inhibit the expression and degradation activity of calpain following ischemia-reperfusion injury, providing further insight into the therapeutic benefits of methylprednisolone treatment for spinal cord injury.

关键词： Methylprednisolone Spinal Cord Injury Ischemia-Reperfusion Injury Calpain

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我国辣椒产业发展现状、主要挑战与应对之策

北方园艺 2023年第14期 153-158页

作者：张子峰山西翼城县农业生态保护发展中心山西临汾041000

我国作为世界上辣椒第一生产国和消费国,辣椒产业的健康发展对保障辣椒常年稳健供应和农户增收意义重大。我国辣椒产业发展的现状良好,表现在生产规模全球第一、产业布局持续优化、辣椒设施栽培和加工水平不断提高、经济效益好、辣椒种... 详细信息

我国作为世界上辣椒第一生产国和消费国,辣椒产业的健康发展对保障辣椒常年稳健供应和农户增收意义重大。我国辣椒产业发展的现状良好,表现在生产规模全球第一、产业布局持续优化、辣椒设施栽培和加工水平不断提高、经济效益好、辣椒种业上不担心“卡脖子问题”,但仍面临一些挑战,如机械化水平低、辣椒种业创新有待提升、病虫害防治难度加大、辣椒加工的工业化和国际化水平较低、市场销售体系不健全,为此应提升辣椒生产的机械化水平、促进辣椒育种创新能力提升、做好辣椒病虫害防治、推动辣椒加工升级以及健全辣椒市场销售体系。

关键词：辣椒产业辣椒育种机械化辣椒制品

Quasi Proportional-Resonant Control of Single-Phase Photovoltaic Grid-Connected System with LCL Filter

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Quasi Proportional-Resonant Control of Single-Phase Photovol...

饲料企业产品售后服务与产品营销协同发展研究

第26届中国控制与决策会议

作者： Yumei Liu Rui Bai Daoqian Wang Wenge Ma zifeng zhang School of Electrical Engineering of Liaoning University of Technology Electric Power Research Institute Shenzhen BYD Auto Co.Ltd

ISBN: (纸本)9781479937097

The grid-connected photovoltaic（PV） power generation is expected to be more widespread and paid more attention. In order to suppress the high-frequency harmonic current of PV grid-connected inverters, LCL filter is utilized to lower the current total harmonic distortion rate. On the basis of LCL filter, double-loop current control scheme with the quasi proportional-resonant method is designed. The proposed control method can reduce the steady-state error of the current, and eliminate the impact of the grid frequency offset on the net current. And the system oscillation caused by the resonance frequency can be decreased, too. Therefore, the stability and robustness of the grid-connected system are improved. Simulation is implemented, and the simulation results confirm the effectiveness of the proposed control method.

关键词： Quasi Proportional-Resonant LCL Filter Single-Phase PV Grid-Connected Simulation

来源： cnki会议评论

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中国饲料 2020年第19期 87-90页

作者：张子峰石家庄职业技术学院河北石家庄050081

在我国经济发展新常态背景下,饲料企业已结束高速增长,进入行业整合、微利竞争的新时代。高速增长时代,大部分饲料企业形成以营销为导向的经营策略,售后服务仅为附加形式。这一方式已不符合当下的竞争态势。基于这一背景,本文首先分析... 详细信息

在我国经济发展新常态背景下,饲料企业已结束高速增长,进入行业整合、微利竞争的新时代。高速增长时代,大部分饲料企业形成以营销为导向的经营策略,售后服务仅为附加形式。这一方式已不符合当下的竞争态势。基于这一背景,本文首先分析了饲料企业产品营销、产品售后服务的现状,并指出了其中存在的主要问题。其次,提出了企业从营销组织、考核、团队三个方向进行改革,以构建产品售后与营销协同发展的有效模式。此外,还探讨了互联网技术在营销与售后协同模式构建中的重要作用。

关键词：售后服务产品营销饲料企业协同发展