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Characterization of Rheum palmatum mitochondrial genome and comparative analysis among Caryophyllales species

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Acupuncture and Herbal Medicine 2023年第4期3卷 323-332页

作者： longlong gao Lijun Hao Wenjie Xu Tianyi Xin Chi Song Yulin Lin Lingping Zhu Jingyuan Song Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of the People’s Republic of ChinaEngineering Research Center of Chinese Medicine Resource of Ministry of EducationInstitute of Medicinal Plant DevelopmentPeking Union Medical College and Chinese Academy of Medical SciencesBeijingChina Institute of Herbgenomics State Key Laboratory of Southwest Chinese Medicine ResourcesPharmacy CollegeChengdu University of Traditional Chinese MedicineChengduChina

Objective:This work aimed to report the first complete mitochondrial genome(mitogenome)of Rheum palmatum,summarize the features of Caryophyllales mitogenomes,and to reveal the potential of utilizing the mitogenomes of R.palmatum and other Caryophyllales species for inferring phylogenetic relationships and species identification.Methods:Both Illumina short reads and PacBio HiFi reads were utilized to obtain a complete mitogenome of R.palmatum.A variety of bioinformatics tools were employed to characterize the R.palmatum mitogenome,compare the reported mitogenomes in Caryophyllales and conduct phylogenetic analysis.Results:The mitogenome of R.palmatum was assembled into a single master circle of 302,993 bp,encoding 35 known protein-coding genes,18 transfer RNA genes,and three ribosome RNA genes.A total of 249 long repeats and 49 simple sequence repeats were identified in this mitogenome.The sizes of mitogenomes in Caryophyllales varied from 253 kb to 11.3 Mb.Among them,23 mitogenomes were circular molecules,one was linear,and one consisted of relaxed circles,linear molecules,and supercoiled DNA.Out of the total mitogenomes,11 were single-chromosome structure,whereas the remaining 14 were multi-chromosomal organizations.The phylogenetic analysis is consistent with both the Engler system(1964)and the Angiosperm Phylogeny Group III system.Conclusions:We obtained the first mitogenome of R.palmatum,which consists of a master circle.Mitogenomes in Caryophyllales have variable genome sizes and structures even within the same species.Circular molecules are still the dominant pattern in Caryophyllales.Single-chromosome mitogenomes account for nearly a half of all the mitogenomes in Caryophyllales,in contrast to previous studies.It is feasible to utilize mitochondrial genomes for inferring phylogenetic relationships and conducting species identification.

关键词： Caryophyllales Mitochondrial genome Molecular identification Phylogenetic analysis Rheum palmatum

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基于响应面法的过轴式旋流器分离性能优化

化学工程 2024年第5期52卷 59-63页

作者：李枫史龙龙邢雷高扬关帅东北石油大学机械科学与工程学院黑龙江大庆163318 黑龙江石油石化多相介质处理及污染防治重点实验室黑龙江大庆163318 中国石油勘探开发研究院北京100083

为解决旋流器在井下狭小空间内的适用性问题,提出一种新型过轴式旋流器,通过响应面法对构建的旋流器结构参数与分离效率间的数学关系模型进行结构优化。采用数值模拟方法,对优化前后旋流器在不同处理量与含水率条件下旋流器内流场特性... 详细信息

为解决旋流器在井下狭小空间内的适用性问题,提出一种新型过轴式旋流器,通过响应面法对构建的旋流器结构参数与分离效率间的数学关系模型进行结构优化。采用数值模拟方法,对优化前后旋流器在不同处理量与含水率条件下旋流器内流场特性及分离效率的对比情况开展研究。结果表明:优化后模型效率均优于优化前,优化后模型处理量在2—6.5 m^(3)/h变化,处理量为6.5 m^(3)/h时分离性能最佳,分离效率由60.30%增至97.10%;含水率在92%—99%变化,含水率99%时分离性能最佳,分离效率由93.15%增至99.72%。采用数值模拟与实验相结合的方法,对优化后旋流器在不同分流比条件下分离效率开展研究,数值模拟与实验结果呈现出较好的一致性,验证结构优化的可行性及数值模拟结果的准确性。

关键词：水力旋流器响应面法分离效率结构参数操作参数

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可控电流源型换流器功率解耦控制策略

中国电机工程学报 2024年第9期44卷 3619-3631,I0024页

作者：陈龙龙魏晓光张闻闻汤广福崔翔高冲新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 先进输电技术国家重点实验室(国网智能电网研究院有限公司) 北京市昌平区102209

可控电流源型换流器(current source converter,CSC)是高压直流输电技术重要研究方向,随着逆阻型IGCT器件的发展,推动其应用技术上已经可行。但由于其电流源特性,大部分研究主要考虑定直流电流策略,针对定直流电压下的功率控制策略研究... 详细信息

可控电流源型换流器(current source converter,CSC)是高压直流输电技术重要研究方向,随着逆阻型IGCT器件的发展,推动其应用技术上已经可行。但由于其电流源特性,大部分研究主要考虑定直流电流策略,针对定直流电压下的功率控制策略研究较少,严重制约其工程化发展。该文首先建立可控CSC的数学模型,获得有功、无功的影响变量。接着,对电容电压的d-q轴分量进行解耦,提出换流器内环和外环控制策略。然后,以直流电压和调制比为约束条件,对换流器的功率运行范围进行分析。最后,搭建基于常规直流和可控电流源的混合输电系统,对所提的控制策略进行分析,重点对单位功率因数运行和定直流电压时策略下功率调节特性进行仿真分析,对CSC在单相接地故障下抵御换相失败能力和向孤岛系统送电进行仿真。研究结果表明:所提的功率控制策略,能够实现有功、无功的解耦控制,以及对功率的有效调节,具备抵御换相失败的能力。

关键词：高压直流输电系统电流源型换流器功率控制解耦控制

基于双层模型的可控电流源换流器损耗优化方法

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电网技术 2024年第6期48卷 2651-2659页

作者：陈龙龙高冲张胤禄张升王以璇张闻闻先进输电技术国家重点实验室(国网智能电网研究院有限公司) 北京市昌平区102209 新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206

逆阻型集成门极换流晶闸管是构建可控关断电流源型换流器(current source converter,CSC)的可行器件之一。在换流器运行过程中,损耗的产生使得器件芯片结温上升,从而限制了换流阀的运行能力,因此必须明确并优化CSC中器件结温情况。该文... 详细信息

逆阻型集成门极换流晶闸管是构建可控关断电流源型换流器(current source converter,CSC)的可行器件之一。在换流器运行过程中,损耗的产生使得器件芯片结温上升,从而限制了换流阀的运行能力,因此必须明确并优化CSC中器件结温情况。该文提出了系统性的损耗特性、约束条件,建立了损耗抑制的双层模型,并给出了求解方法。提出了缓冲电路和损耗分析的综合设计方法,对缓冲回路及杂散参数范围进行了研究,对比了优化后的CSC与传统直流和柔性直流换流阀的损耗。结果表明,基于该模型的计算参数,器件损耗为5.7kW,电阻损耗约为1.8kW,器件结温增量为38℃,CSC的损耗与系统占比为0.54%。

关键词：逆阻型集成门极换流晶闸管换流阀损耗电流源型换流器

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可控电流源型换流器IGCT串联均压技术

中国电机工程学报 2024年第12期44卷 4859-4868,I0021页

作者：陈龙龙汤广福魏晓光王以璇崔翔高冲张闻闻先进输电技术国家重点实验室(国网智能电网研究院有限公司) 北京市昌平区102209 怀柔实验室北京市怀柔区101400 新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206

高压大功率逆阻型集成门极换流晶闸管(integrated gate commutation thyristor,IGCT)串联是可控电流源型换流器的关键技术之一,主要面临开通和关断不一致将会引起击穿的问题,目前尚缺乏深入研究和实验测试。该文首先分析可控电流源型换... 详细信息

高压大功率逆阻型集成门极换流晶闸管(integrated gate commutation thyristor,IGCT)串联是可控电流源型换流器的关键技术之一,主要面临开通和关断不一致将会引起击穿的问题,目前尚缺乏深入研究和实验测试。该文首先分析可控电流源型换流器均压问题产生的原因,提出串联器件均压电路。接着,对开通不一致影响因素进行分析,给出IGCT使用电压和保护电压的配合关系,以确保开通过程器件安全。然后,对IGCT的自然和主动关断2种特殊关断过程影响因素进行分析,给出缓冲电路参数选择方法。最后,研制8级串联的IGCT模块样机,搭建实验平台进行测试。结果表明,所提方法能够有效抑制IGCT关断电压过冲,均压不一致性控制在8%以内。

关键词：电流源型换流器均压特性静态均压开通一致性关断一致性

Injecting spectral indices to transferable convolutional neural network under imbalanced and noisy labels for Landsat image classification

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International Journal of Digital Earth 2022年第1期15卷 437-462页

作者： Xuemei Zhao Jun Wu Haijian Wang Xingyu gao longlong Zhao School of Electronic Engineering and Automation Guilin University of Electronic TechnologyGuangxiPeople's Republic of China Guangxi Key Laboratory of Manufacturing System & Advanced Manufacturing Technology School of Mechanical and Electrical EngineeringGuilin University of Electronic TechnologyGuangxiPeople's Republic of China Center for Geospatial Information Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesBeijingPeople's Republic of China

Stable and continuous remote sensing land-cover mapping is important for agriculture,ecosystems,and land management.Convolutional neural networks(CNNs)are promising methods for achieving this goal.However,the large number of high-quality training samples required to train a CNN is difficult to acquire.In practice,imbalanced and noisy labels originating from existing land-cover maps can be used as alternatives.Experiments have shown that the inconsistency in the training samples has a significant impact on the performance of the CNN.To overcome this drawback,a method is proposed to inject highly consistent information into the network,to learn general and transferable features to alleviate the impact of imperfect training samples.Spectral indices are important features that can provide consistent information.These indices can be fused with CNN feature maps which utilize information entropy to choose the most appropriate CNN layer,to compensate for the inconsistency caused by the imbalanced,noisy labels.The proposed transferable CNN,tested with imbalanced and noisy labels for inter-regional Landsat time-series,not only is superior in terms of accuracy for land-cover mapping but also demonstrates excellent transferability between regions in both time series and cross-regional Landsat image classification.

关键词： Landsat image classification imbalanced and noisy label convolutional neural network(CNN) transferability feature fusion information entropy

近距离煤层重复采动覆岩破坏规律及“两带”发育高度分析

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中国矿业 2024年第3期33卷 160-167页

作者：王文才吴周康李龙龙王鹏高小雷杨少晨内蒙古科技大学矿业与煤炭学院内蒙古包头014010 西安科技大学能源学院陕西西安710054 鄂尔多斯市智慧能源科技有限公司内蒙古鄂尔多斯017000

为研究近距离煤层重复采动下覆岩破坏规律与“两带”发育高度,预防工作面开采过程中由导水漏风通道引起的工作面顶板漏水、采空区自燃等各种安全事故,以鄂尔多斯市某煤矿为工程背景,采用井下窥视法和数值模拟对近距离煤层开采后覆岩破... 详细信息

为研究近距离煤层重复采动下覆岩破坏规律与“两带”发育高度,预防工作面开采过程中由导水漏风通道引起的工作面顶板漏水、采空区自燃等各种安全事故,以鄂尔多斯市某煤矿为工程背景,采用井下窥视法和数值模拟对近距离煤层开采后覆岩破坏规律以及“两带”发育高度进行分析,揭示了规律形成的原因。研究结果表明:在近距离煤层重复采动影响下,“两带”发育高度远超过上煤层开采,下煤层推进80 m时裂隙带最大发育高度为88 m,与地表贯通形成导水漏风通道;初次采动与重复采动时的裂采比分别为19.33、29.33;裂隙带的发育呈台阶式上升,阶段间的变化表现为激跳形式;覆岩的破坏表现为“拱形→帽形→马鞍形→外O内蝶形”;数值模拟及拟合公式所预测的“两带”发育高度与实测值之间误差率为1%左右,验证了预测的准确性,可为相似工作面的开采以及相似工程提供借鉴。

关键词：近距离煤层岩移规律 “两带”发育高度井下窥视数值模拟

Comparisons and Improvements of Key Operating Characteristics of Current Source Converter Applied in HVDC System

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1601-1612页

作者： Wenwen Zhang longlong Chen Xiaoguang Wei Guangfu Tang Lei Qi Chong gao Zhiyuan He the North China Electric Power University Beijing 102206China the State Key Laboratory of Advanced Power Transmission Technology Beijing Institute Of Smart EnergyBeijing 102206China the State Grid Smart Grid Research Institute Co.Ltd Beijing 102209China

Because of its controlled power factor and no commutation failure,current source converter(CSC)made up of reverse-blocking IGCTs(RB-IGCTs)offers broad application prospects in the field of HVDC system.Valve voltage and power operating range as the most important operating characteristics should be paid attention to but they are always contradictory.First,the relationship between valve voltage and modulation index is obtained.In particular,valve voltage of converter under the three typical modulation methods is compared,analyzed,and verified.Second,with the help of the independent control strategy and coordinated control strategy of both ends,power operating ranges of the three modulation methods are comprehensively analyzed and compared.Third,in order to solve power coupling at a low active power,the improved coordination control strategy at both ends in this paper is proposed and the relationships among active power,reactive power,DC current and phase angle difference are given in detail.Finally,a 500 kV/3 kA simulation system was built in PSCAD/EMTDC to obtain comparison results of the key operating characteristics of CSC under different modulation methods and the converter can realize unity power operation under random active power after adopting the improved coordinated control strategy,and DC current does not decrease to zero,verifying effectiveness of the coordinated control strategy.

关键词： Current source converter improved coordinated control strategy reverse-blocking IGCT valve voltage

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智能光控技术在城市照明中的节能与环保策略

中国高新科技 2024年第5期 121-123页

作者：朱龙龙青岛市户外广告与亮化发展中心山东青岛266034

研究目的在于评估智能光控技术在夜间能源利用效率、光污染减少及提高居民夜间生活质量方面的实际效果。研究结果表明,该技术在城市照明中取得显著成果。在夜间,系统能够自动降低照明亮度,避免过度照明,平均实现了15%~30%的能源节约。同... 详细信息

研究目的在于评估智能光控技术在夜间能源利用效率、光污染减少及提高居民夜间生活质量方面的实际效果。研究结果表明,该技术在城市照明中取得显著成果。在夜间,系统能够自动降低照明亮度,避免过度照明,平均实现了15%~30%的能源节约。同时,通过实时监测人流情况,系统在有人活动的区域实现了智能调高亮度,提高了照明质量,进一步降低了光污染。智能化调光方案不仅提高了城市照明的能源利用效率,也为城市居民提供了更为宜人的夜间环境。

关键词：智能光控技术城市照明节能环保