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Simultaneous identification of multiple animal-derived components in meat and meat products by using MNP marker based on high-throughput sequencing 被引量:1
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作者 Yan Yi Zhanyue Jiang +9 位作者 Lixia Ma Xiaoni Hou Lun Li Deping Ye Juanlan Du Hai Peng Guoquan Han Huaiping Li Jiangwen Tang Lihua Zhou 《Food Science and Human Wellness》 2025年第4期1566-1575,共10页
In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology bas... In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients. 展开更多
关键词 Meat and meat products Multiple nucleotide polymorphism marker method High-throughput sequencing Animal-derived component identification
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Feature-driven topology optimization method preserving component sequences considering turning angle constraint
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作者 Dongsheng Jia Lei Liu +2 位作者 Jihong Zhu Yu Zhang Vassili Toropov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2024年第10期41-56,共16页
Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing ... Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing of continuous fibre-reinforcedpolymer structures, customized stents, and soft robotics parts. This study presents a feature-driven method that preservescomponent sequences accounting for engineering requirements. The chain-of-bars design variables setting scheme is developedto realize the sequential component’s layout, which sets the current bar’s end point as the next bar’s start point. The total lengthof the printing path is constrained to reduce the consumption of material accurately. Also, the angle between adjacent bars isconstrained to avoid sharp angles at the turning point of the 3D printing path. Next, the sensitivity analysis considering theinter-dependence of substructures is performed. Several numerical examples are given to demonstrate the validity and merits ofthe proposed method in designing structures preserving component sequences. 展开更多
关键词 Topology optimization component sequence preservation Chain-like structures Feature-driven method Additive manufacturing
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Examining gut microbiota and metabolites to clarify mechanisms of Dimocarpus longan Lour leaf components against type 2 diabetes
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作者 Piao-Xue Zheng Chun-Lian Lu +8 位作者 Yan-Li Liang Yu-Ming Ma Jia-Wen Peng Jing-Jing Xie Jia-Li Wei Si-SiChen Zhi-Dong Ma Hua Zhu Jie Liang 《World Journal of Diabetes》 2025年第7期308-327,共20页
AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of ... AIM To investigate the material basis and mechanism underlying the therapeutic effect of DLC in T2DM.METHODS T2DM was triggered in rats using a high-sugar,high-fat diet alongside 35 mg/kg streptozotocin.The effect of DLC on the intestinal microbiota in T2DM rats was analyzed via 16S rDNA sequencing.Targeted metabolomics was conducted to evaluate the impact of DLC on the levels of nine short-chain fatty acids(SCFAs).Untargeted metabolomics examined DLC-induced alterations in fecal metabolites and associated metabolic pathways.Additionally,Spearman’s correlation analysis assessed gut microbiota and fecal metabolite relationships.RESULTS DLC significantly attenuated pathological weight loss,reduced fasting blood glucose levels,restored blood sugar homeostasis,and ameliorated dyslipidemia in T2DM rats.The 16S rDNA sequencing revealed that DLC enhanced microbial diversity and reversed intestinal dysbiosis.Targeted metabolomics indicated decreased acetic acid and propionic acid levels and increased butyric acid,isobutyric acid,and 2-methylbutyric acid levels after DLC treatment.Untargeted metabolomics revealed 57 metabolites with altered expression associated with amino acid,carbohydrate,purine,and biotin pathways.The Spearman analysis demonstrated significant links between specific gut microbiota taxa and fecal metabolites.CONCLUSION DLC may exert hypoglycemic effects by modulating intestinal flora genera,SCFA levels,and fecal metabolites. 展开更多
关键词 Dimocarpus longan Lour leaf components Type 2 diabetes 16S rDNA sequencing Short-chain fatty acids Metabolomics
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Pse-in-One 2.0: An Improved Package of Web Servers for Generating Various Modes of Pseudo Components of DNA, RNA, and Protein Sequences 被引量:12
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作者 Bin Liu Hao Wu Kuo-Chen Chou 《Natural Science》 2017年第4期67-91,共25页
Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and compr... Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and comprehensive as suggested by many users, the updated package has incorporated 23 new pseudo component modes as well as a series of new feature analysis approaches. It is available at http://bioinformatics.hitsz.edu.cn/Pse-in-One2.0/. Moreover, to maximize the convenience of users, provided is also the stand-alone version called “Pse-in-One-Analysis”, by which users can significantly speed up the analysis of massive sequences. 展开更多
关键词 PSEUDO componentS DNA sequenceS RNA sequenceS Protein sequenceS
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Disassembly sequence planning using component-joint graph and ant colony optimization
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作者 Zheng Menglei Tian Ling Liu Beibei 《Computer Aided Drafting,Design and Manufacturing》 2016年第1期54-57,共4页
Disassembly sequence planning is an important step of mechanical maintenance. This article presents an integrated study about the generation and optimizing algorithm of the disassembly sequence. Mechanical products ar... Disassembly sequence planning is an important step of mechanical maintenance. This article presents an integrated study about the generation and optimizing algorithm of the disassembly sequence. Mechanical products are divided into two categories of components and connectors. The article uses component-joint graph to represent assembly constraints, including the incidence constraints are represented by incidence matrix and the interference constraints are represented by interference constraints. The inspiring factor and pheromone matrix are calculated according to assembly constraints. Then the ant generates its own disassembly sequences one by one and updates the inspiring factor and pheromone matrix. After all iterations, the best disassembly sequence planning of components and connectors are given. Finally, an application instance of the disassembly sequence of the jack is presented to illustrate the validity of this method. 展开更多
关键词 disassembly sequence planning component-joint graph ant colony algorithms
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Bayesian network structure learning by dynamic programming algorithm based on node block sequence constraints
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作者 Chuchao He Ruohai Di +1 位作者 Bo Li Evgeny Neretin 《CAAI Transactions on Intelligence Technology》 2024年第6期1605-1622,共18页
The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study propose... The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study proposes a DP algorithm based on node block sequence constraints.The proposed algorithm constrains the traversal process of the parent graph by using the M-sequence matrix to considerably reduce the time consumption and space complexity by pruning the traversal process of the order graph using the node block sequence.Experimental results show that compared with existing DP algorithms,the proposed algorithm can obtain learning results more efficiently with less than 1%loss of accuracy,and can be used for learning larger-scale networks. 展开更多
关键词 Bayesian network(BN) dynamic programming(DP) node block sequence strongly connected component(SCC) structure learning
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Unexpected metastasis of intraductal papillary neoplasm of the bile duct without an invasive component to the brain and lungs:A case report 被引量:6
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作者 Nguyen Hai Nam Kojiro Taura +7 位作者 Masashi Kanai Keita Fukuyama Norimitsu Uza Hirona Maeda Yojiro Yutaka Toyofumi F Chen-Yoshikawa Manabu Muto Shinji Uemoto 《World Journal of Gastroenterology》 SCIE CAS 2020年第3期366-374,共9页
BACKGROUND Despite an expanding number of studies on intraductal papillary neoplasm of the bile duct(IPNB),distant metastasis remains unexplained especially in cases of carcinoma in situ.In the present study,we report... BACKGROUND Despite an expanding number of studies on intraductal papillary neoplasm of the bile duct(IPNB),distant metastasis remains unexplained especially in cases of carcinoma in situ.In the present study,we report a rare and interesting case of IPNB without invasive components that later metastasized to lungs and brain.CASE SUMMARY A 69-year-old male was referred to our hospital due to suspected cholangiocarcinoma.Laboratory tests on admission reported a mild elevation of alkaline phosphatase,γ-glutamyl transpeptidase,and total bilirubin in serum.Endoscopic retrograde cholangiography revealed a filling defect in the common bile duct(CBD)extending to the left hepatic duct.Peroral cholangioscopy delineated a tumor in the CBD that had a papillary pattern.Multidetector computed tomography and magnetic resonance cholangiopancreatography detected partial blockage ot interlude in the CBD leading to cholestasis without evidence of metastasis.Therefore,a diagnosis of IPNB cT1N0M0 was established.Left hepatectomy with bile duct reconstruction was performed.Pathological examination confirmed an intraepithelial neoplasia pattern without an invasive component and an R0 resection achievement.The patient was monitored carefully by regular examinations.However,at 32 mo after the operation,a 26 mm tumor in the lungs and a 12 mm lesion in the brain were detected following a suspicious elevated CA 19-9 level.Video-assisted thoracoscopic surgery of left upper lobectomy and stereotactic radiotherapy are indicated.In addition to histopathological results,a genomic profiling analysis using whole exome sequencing subsequently confirmed lung metastasis originating from bile duct cancer.CONCLUSION This case highlights the important role of genomic profiling analysis using whole exome sequencing in identifying the origin of metastasis in patients with IPNB. 展开更多
关键词 Intraductal papillary neoplasm of the bile duct Distant metastasis Invasive component Whole exome sequencing CA 19-9 Case report
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Performance improvement of software component with partial evaluation
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作者 毛宏燕 黄林鹏 李明禄 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第1期95-99,共5页
To avoid the complexity and inefficiency for specific applications of the current software architecture, a novel approach using partial evaluation is proposed to improve the running performance of components. The gene... To avoid the complexity and inefficiency for specific applications of the current software architecture, a novel approach using partial evaluation is proposed to improve the running performance of components. The generic program was specialized into domain-specific realization for the known knowledge and environments. The syntax and semantic(adj.) were analyzed based on byte code instruction sequences, and partial evaluation rules depicted how to perform the specialization. The partial evaluation for object-oriented programs was implemented. The experimental results show that partial evaluation is effective to speed up the running efficiency. The more generality and scalability can be obtained by the integration of partial evaluation with the favorable design mechanisms and compiler optimization technology. 展开更多
关键词 partial evaluation running efficiency component byte code instruction sequence
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An Efficient and Cost-Saving Component Scheduling Algorithm Using High Speed Turret Type Machines for a Board Containing Multiple PCBs
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作者 Wei-Shung Chang Chiuh-Cheng Chyu 《Intelligent Control and Automation》 2011年第2期86-94,共9页
This paper considers a material constrained component scheduling problem during the high speed surface mount manufacturing stage in printed circuit board (PCB) assembly, where each piece of board contains an even numb... This paper considers a material constrained component scheduling problem during the high speed surface mount manufacturing stage in printed circuit board (PCB) assembly, where each piece of board contains an even number of identical PCBs. To accomplish the production, material requirements must be predetermined and incorporated as restraints into the scheduling problem, which has the objective of minimizing production completion time (makespan). A solution procedure is developed based on the following strategies: 1) Each machine is responsible for the same PCBs of each piece, 2) Components of the same types may use one or more feeder locations, 3) Component types are clustered based on their suitable placement speeds, 4) A heuristic using a bottom-up approach is applied to determine the component placement sequence and the feeder location assignment for all machines. Velocity estimate functions of the turret, XY table, and feeder carriage were derived based on empirical data. An experiment using Fuji CP732E machines was conducted on two real life instances. Experimental results indicate that our method performs 32.96% and 10.60% better than the Fuji-CP software for the two instances, in terms of the makespan per piece of board. 展开更多
关键词 Printed Circuit Boards Assembly Surface Mount Technology Heuristics component Placement sequence FEEDER Location Assignment
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Fully Decoupled Branch Energy Balancing Control Method for Modular Multilevel Matrix Converter Based on Sequence Circulating Components
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作者 Zexin Zhao Weijiang Chen +5 位作者 Zhichang Yang Guoliang Zhao Bin Han Yunfei Xu Nianwen Xiang Shulai Wang 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第1期235-247,共13页
The modular multilevel matrix converter(M3C)is a potential frequency converter for low-frequency AC transmission.However,capacitor voltage control of high-voltage and largecapacity M3C is more difficult,especially for... The modular multilevel matrix converter(M3C)is a potential frequency converter for low-frequency AC transmission.However,capacitor voltage control of high-voltage and largecapacity M3C is more difficult,especially for voltage balancing between branches.To solve this problem,this paper defines sequence circulating components and theoretically analyzes the influence mechanism of different sequence circulating components on branch capacitor voltage.A fully decoupled branch energy balancing control method based on four groups of sequence circulating components is proposed.This method can control capacitor voltages of nine branches in horizontal,vertical and diagonal directions.Considering influences of both circulating current and voltage,a cross decoupled control is designed to improve control precision.Simulation results are taken from a low-frequency transmission system based on PSCAD/EMTDC,and effectiveness and precision of the proposed branch energy balancing control method are verified in the case of nonuniform parameters and an unbalanced power system. 展开更多
关键词 Branch energy balancing control decoupled control low-frequency AC transmission modular multilevel matrix converter(M3C) sequence circulating components
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挖掘机工作过程动力特性仿真及主构件参数多目标优化设计方法 被引量:1
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作者 林述温 陆哲 +3 位作者 危世佳 陈剑雄 顾天奇 谢钰 《中国机械工程》 北大核心 2025年第6期1371-1379,共9页
现有挖掘机主构件参数优化设计方法无法保证挖掘作业全过程多工况位置工作性能最优,且没有考虑作业过程中的能耗特性。研究了以典型工况作业全过程动力和能耗特性为目标的挖掘机工作装置主构件参数多目标优化设计方法。通过对基于ADAMS... 现有挖掘机主构件参数优化设计方法无法保证挖掘作业全过程多工况位置工作性能最优,且没有考虑作业过程中的能耗特性。研究了以典型工况作业全过程动力和能耗特性为目标的挖掘机工作装置主构件参数多目标优化设计方法。通过对基于ADAMS的参数化挖掘机虚拟样机的动力学仿真,分析了四种典型工况作业过程的液压缸驱动力和功率特性,确定了工作装置的优化工况,建立了新的综合考虑挖掘机典型工况作业过程液压缸驱动力传动比和功率特性的多目标优化数学模型,并结合实例对挖掘机整机工作装置参数化虚拟样机的铲斗、斗杆和动臂主构件参数进行顺序多目标优化。优化结果表明:该优化设计方法可显著提高挖掘机作业全过程工作装置传递动力的性能,降低液压缸能耗。 展开更多
关键词 挖掘机 主构件参数 虚拟样机 过程特性 多目标优化 顺序优化
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基于波形相似性的柔性互联配电网短路故障区段定位方法 被引量:2
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作者 陈继明 陈文淙 +2 位作者 仉志华 于馨玮 徐乾 《电力工程技术》 北大核心 2025年第1期104-114,共11页
由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段... 由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。 展开更多
关键词 柔性互联配电网(FDN) 柔性多状态开关(SNOP) 故障分析 波形相似性 故障定位 电流正序分量
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海上中频风电系统积分滑模控制策略研究
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作者 段军 朱铭炼 +3 位作者 姚宏洋 欧阳有鹏 殷冠贤 李天皓 《自动化仪表》 2025年第4期42-47,53,共7页
不平衡电网电压下,海上中频风电中模块化多电平换流器-高压直流输电(MMC-HVDC)系统会暴露出功率波动大、网侧电流畸变等问题,而单一使用滑模控制的模块化多电平换流器(MMC)存在滑模面抖振及超调量高等明显弊端。对此,提出一种基于积分... 不平衡电网电压下,海上中频风电中模块化多电平换流器-高压直流输电(MMC-HVDC)系统会暴露出功率波动大、网侧电流畸变等问题,而单一使用滑模控制的模块化多电平换流器(MMC)存在滑模面抖振及超调量高等明显弊端。对此,提出一种基于积分滑模控制的交流电流控制策略,以实现交流侧电流负序分量的抑制及正序分量的高精度跟踪。首先,在不平衡状态下,整流侧MMC可实现电流环dq轴参考量的正负序分离。然后,阐述了滑模控制下系统状态点的运动轨迹;引入积分项设计滑模平面,利用一种新型饱和函数改进趋近律,增强了系统的抗干扰能力。最后,将所设计的积分滑模控制器应用于MMC电流内环控制,使得交流侧电流系统状态点可在较短时间内从趋近状态转入滑动状态。在不平衡电网电压工况下,所提策略具有鲁棒性强、稳态控制精度高、动态响应能力好等优势。 展开更多
关键词 海上发电 滑模抖振 正序分量跟踪 积分滑模 负序分量抑制 正负序分离
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基于价值评估的废旧产品拆卸序列与拆卸深度决策
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作者 张华 殷俊鸿 +3 位作者 鄢威 马峰 江志刚 朱硕 《组合机床与自动化加工技术》 北大核心 2025年第1期143-149,共7页
为解决拆卸序列规划(disassembly sequence planning, DSP)中存在的复杂模型构建难题、组合爆炸以及拆解深度决策不合理等问题,提出了一种基于知识图谱属性图模块化的改进方法实现废旧产品拆卸信息的获取,并提出了一种基于剩余回收效益... 为解决拆卸序列规划(disassembly sequence planning, DSP)中存在的复杂模型构建难题、组合爆炸以及拆解深度决策不合理等问题,提出了一种基于知识图谱属性图模块化的改进方法实现废旧产品拆卸信息的获取,并提出了一种基于剩余回收效益评估的拆解序列与拆解深度综合决策方法。首先,通过分析废旧产品的拆卸特征以及产品内部零部件的信息和拆卸联接关系,构建支持拆解的模块化属性图模型;其次,采用组合赋权及改进的TOPSIS灰色关联分析法构建了零件回收综合评价模型的多属性决策模型,对产品综合内部零部件剩余回收效益进行排序;再次,提出了基于改进遗传-粒子群算法的完全拆解序列生成方法,并结合剩余回收效益值进行废旧产品零件的拆解深度决策。以废旧汽车动力电池包为例对上述模型和方法进行了验证,证明了该方法的可行性和高效性。 展开更多
关键词 废旧产品 知识图属性图模型 零件回收综合评价 拆卸序列优化 拆卸深度决策
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电压序分量结合测量阻抗的选相方法
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作者 赵志宏 杜兆强 +4 位作者 伍叶凯 聂娟红 熊军 黄继伟 李丽朋 《电工电气》 2025年第6期42-48,共7页
随着新型电力系统的不断推广应用,高压线路后备保护的相间电流突变量选相元件、稳态零负序电流选相元件以及弱馈选相元件均受到不同程度的影响,尤其是线路发生反方向出口两相短路接地时非故障相电压值较小,保护可能误选为三相故障,导致... 随着新型电力系统的不断推广应用,高压线路后备保护的相间电流突变量选相元件、稳态零负序电流选相元件以及弱馈选相元件均受到不同程度的影响,尤其是线路发生反方向出口两相短路接地时非故障相电压值较小,保护可能误选为三相故障,导致相间距离Ⅲ段保护误动作。提出了电压序分量结合测量阻抗的选相方法,对比原有的电流序分量选相方法,该选相方法性能明显提高,具有较好的选相效果,可以解决反方向出口两相短路接地时相间距离Ⅲ段保护误动问题。 展开更多
关键词 新型电力系统 选相元件 电压序分量 测量阻抗 保护误动
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基于叶状枝形态学特征和trnH-psbA序列的15份天门冬属种质资源鉴定
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作者 王辉 FARDOUS Mohammad Safiul Azam +5 位作者 MUHAMMAD Idrees 江心雨 钱干瑞 龙海林 李雪芹 王芊芊 《草业科学》 北大核心 2025年第4期1024-1035,共12页
以采自西南地区的15份天门冬属(Asparagus)植物为试材,开展基于叶状枝形态学特征和叶绿体trnH-psbA序列的综合分析,为该属种质资源鉴定及遗传多样性分析提供理论依据。形态学结果表明,15份样本间的15个形态学特征有一定相关性,主成分分... 以采自西南地区的15份天门冬属(Asparagus)植物为试材,开展基于叶状枝形态学特征和叶绿体trnH-psbA序列的综合分析,为该属种质资源鉴定及遗传多样性分析提供理论依据。形态学结果表明,15份样本间的15个形态学特征有一定相关性,主成分分析将所有形态特征值转化为4个主成分(特征值>1),累计贡献率81.42%,其中,主成分1反映叶状枝粗细,主成分2反映保卫细胞大小,主成分3、4反映表皮细胞大小。在主成分分析的基础上进行聚类分析,在遗传距离阈值12.5处将供试材料聚为3大类群:类群Ⅰ包含样本数11种,占参试材料的73.33%,特征表现为叶状枝直线型,多数形态特征值介于类群Ⅱ、Ⅲ之间;类群Ⅱ3种,特征表现为叶状枝新月形、数量少、宽度值大;类群Ⅲ包含1个样本,占参试材料的6.67%,特征表现为叶状枝针状,数量多,长度和宽度值小,气孔小而少,表皮细胞短而多。trnH-psbA序列测序结果进一步表明,15份样本的trnH-psbA序列全长约750 bp,对位排列后共有691个位点,其中保守位点591个,变异位点124个,简约信息位点55个,单突变位点41个,种间遗传差异大;进化树显示15份天门冬属物种均处于独立分支,除大理天门冬外,其余种均能利用trnH-psbA序列条形码对其进行区分。研究结果为进一步开展天门冬属植物种质资源保护和开发利用提供了必要的理论和实践基础。 展开更多
关键词 天门冬属 叶状枝 形态学特征 trnH-psbA序列 主成分分析 聚类分析 鉴定
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逆变类电源接入条件下传统方向元件适应性分析
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作者 高厚磊 袁通 +1 位作者 彭放 李林 《电力自动化设备》 北大核心 2025年第2期150-158,共9页
逆变类电源(IBS)接入场景下,传统方向元件逐渐暴露出适应性问题,目前缺乏全面的理论分析。为此,结合逆变器控制策略和我国对IBS低电压穿越的最新要求,推导得出了IBS的故障特征;在此基础上,深入分析IBS和负荷在传统方向元件下所呈现出的... 逆变类电源(IBS)接入场景下,传统方向元件逐渐暴露出适应性问题,目前缺乏全面的理论分析。为此,结合逆变器控制策略和我国对IBS低电压穿越的最新要求,推导得出了IBS的故障特征;在此基础上,深入分析IBS和负荷在传统方向元件下所呈现出的相位特征,进一步考虑多种影响因素,定量给出了含IBS线路中传统方向元件的角度变化范围;利用PSCAD/EMTDC和现场录波数据验证理论分析的正确性。理论分析和仿真结果表明,IBS接入场景下,传统方向元件建立的理论基础不再成立,易导致误判发生,不满足继电保护的要求。 展开更多
关键词 逆变类电源 正序故障分量方向元件 90°接线方向元件 适应性分析 低电压穿越 继电保护
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互动语言学理论与汉语应答性成分研究
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作者 王长武 《现代语文》 2025年第5期12-19,共8页
国内学者从互动视角研究汉语的意识形成较早,但并未构建出整体性的、系统性的学术体系。之后,学界受国外互动语言学理论的影响,从多个领域开展了汉语的互动性研究。应答性成分是在话语互动过程中生成的,互动语言学理论应用于应答性成分... 国内学者从互动视角研究汉语的意识形成较早,但并未构建出整体性的、系统性的学术体系。之后,学界受国外互动语言学理论的影响,从多个领域开展了汉语的互动性研究。应答性成分是在话语互动过程中生成的,互动语言学理论应用于应答性成分研究,具有一定的适切性。应答性成分经常使用于对话中的应答话轮部分,通常会受到刺激话轮的制约。无论是共时层面,还是历时层面,应答性成分在口语在线交际中的形成和发展,均具有鲜明的互动特征。应答性成分是考察互动的最佳样本,可以从序列组织、合作共建、在线延伸、协商互动、立场表达、互动行为等六个方面考察应答性成分的互动特征。希望通过这一个案研究,能够为中国语言学学术体系建设提供有益的参考与借鉴。 展开更多
关键词 应答性成分 互动语言学 序列组织 合作共建 在线延伸 协商互动 立场表达
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基于零序电压的海上风电场交流集电线路分层故障定位 被引量:2
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作者 王鹏程 季亮 +3 位作者 任健铭 俞正嘉 李博通 洪启腾 《智慧电力》 北大核心 2025年第3期35-43,共9页
提出了一种基于零序分量的海上风电集电线路不对称接地故障定位方案,以海上风电场交流汇集线路的零序流通路径为基础,搭建了风电场不平衡故障下零序电网模型,并分析了考虑海缆参数特性、交流集电线路接地特性的零序故障特征。通过无分... 提出了一种基于零序分量的海上风电集电线路不对称接地故障定位方案,以海上风电场交流汇集线路的零序流通路径为基础,搭建了风电场不平衡故障下零序电网模型,并分析了考虑海缆参数特性、交流集电线路接地特性的零序故障特征。通过无分支划分算法,确定零序故障子系统,并基于零序电压的故障分量获得故障区段。最后,通过故障区段两端的零序测量信息构建故障方程,利用优化算法求解故障发生的精确位置。通过RTDS仿真结果表明,所提方案能够克服过渡电阻、风机控制等不确定因素的影响,有效实现集电线不对称故障精确定位。 展开更多
关键词 风电场 集电线路 故障定位 不对称接地故障 零序分量
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基于5G的配电网线路纵联电流差动保护零序补偿方法 被引量:1
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作者 许瑞 於岳祥 +2 位作者 李骁 金烨晨 赵舫 《电测与仪表》 北大核心 2025年第4期105-112,共8页
针对配电网线路纵联电流差动保护回路异常故障影响正常供电的问题,提出一种基于5G的配电网线路纵联电流差动保护的零序补偿方法,提升不同故障情况的电流差动保护效果。依据基于5G的配电网特点构建配电网差动保护架构,结合差动保护的原理... 针对配电网线路纵联电流差动保护回路异常故障影响正常供电的问题,提出一种基于5G的配电网线路纵联电流差动保护的零序补偿方法,提升不同故障情况的电流差动保护效果。依据基于5G的配电网特点构建配电网差动保护架构,结合差动保护的原理,分析不投入电容电流补偿和投入电容电流补偿两种保护动作下,基于5G的配电网中线路电容电流问题,并设置不同保护动作情况下的动作门槛值,完成纵联电流差动保护零序补偿。仿真实验结果表明不同故障类型下该方法均具备较好的电流差动零序补偿效果,补偿后电流差动变化小,电流波动最高幅度不超过150 A,且电流差动保护的灵敏性较高,能根据不同故障选择合适的差动保护动作。 展开更多
关键词 基于5G的配电网 纵联电流 差动保护 零序补偿 故障分量差动 灵敏度
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