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Development and identification of a dwarf wheat-Leymus mollis double substitution line with resistance to yellow rust and Fusarium head blight 被引量:3
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作者 Jixin Zhao Yang Liu +7 位作者 Xueni Cheng Yuhui Pang Jiachuang Li Zhenqi Su Jun Wu Qunhui Yang Guihua Bai Xinhong Chen 《The Crop Journal》 SCIE CAS CSCD 2019年第4期516-526,共11页
Leymus mollis (Trin.) Pilger (2n = 4x = 28, NsNsXmXm,), a wild relative of common wheat, possesses many potentially valuable traits for genetic improvement of wheat, including strong, short stems, long spikes with num... Leymus mollis (Trin.) Pilger (2n = 4x = 28, NsNsXmXm,), a wild relative of common wheat, possesses many potentially valuable traits for genetic improvement of wheat, including strong, short stems, long spikes with numerous spikelets, tolerance to drought and cold stresses, and resistance to many fungal and bacterial diseases. In the present study, a wheat-L. mollis double substitution line DM96 was selected from a F6 progeny of a cross between M842-16 (an octoploid Tritileymus line) and D4286 (a Triticum durum line) using genomic in situ hybridization (GISH), simple sequence repeat (SSR) markers, and expressed sequence tagged sequence site (EST-STS) markers. Chromosome analysis at mitosis and meiosis showed that DM96 had a chromosome constitution of 2n = 42 = 21II. GISH analysis indicated that DM96 carried 38 chromosomes from wheat and two homologous pairs of Ns chromosomes from L. mollis. Fluorescent in situ hybridization (FISH) showed that chromosomes 2Ns and 3Ns from L. mollis had replaced wheat chromosomes 2D and 3D in DM96, which was confirmed by SSR and STS markers. The newly developed substitution line DM96 has shorter height, longer spikes and more kernels than its parents and showed high resistance to stripe rust and Fusarium head blight (FHB). Thus, this line is a new bridge material for the production of useful translocation lines for wheat genetic research and genetic improvement of wheat yield and disease resistance in breeding programs. 展开更多
关键词 Disease RESISTANCE double substitution line DWARFING TRITICUM AESTIVUM
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Development and genetic analysis of wheat double substitution lines carrying Hordeum vulgare 2H and Thinopyrum intermedium 2Ai#2 chromosomes 被引量:1
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作者 Jing Wang Chang Liu +4 位作者 Xianrui Guo Ke Wang Lipu Du Zhishan Lin Xingguo Ye 《The Crop Journal》 SCIE CAS CSCD 2019年第2期163-175,共13页
Thinopyrum intermedium and barley are two close relatives of wheat and carry many genes that are potentially valuable for the improvement of various wheat traits. In this study we created wheat double substitution lin... Thinopyrum intermedium and barley are two close relatives of wheat and carry many genes that are potentially valuable for the improvement of various wheat traits. In this study we created wheat double substitution lines by hybridizing different wheat–Th. intermedium and wheat–barley disomic alien substitution lines, with the aim of using genes in Th. intermedium and barley for wheat breeding and investigating the genetic behavior of alien chromosomes and their wheat homoeologs. As expected, we obtained two types of wheat double substitution lines,2D2Ai#2(2B)2H( A) and 2A2 Ai#2(2B)2H(2D), in which different group 2 wheat chromosomes were replaced by barley chromosome 2 H and Th. intermedium chromosome 2Ai#2. The new materials were characterized using molecular markers, genomic in situ hybridization(GISH), and fluorescent in situ hybridization(FISH). GISH and FISH experiments revealed that the double substitution lines harbor 42 chromosomes including 38 wheat chromosomes, a pair of barley chromosomes, and a pair of Th. intermedium chromosomes. Analysis using specific DNA markers showed that two pairs of wheat homoeologous group 2 chromosomes in the new lines were substituted by a pair of 2H and a pair of 2Ai#2 chromosomes. Chromosome 2H showed a higher transmission rate than 2Ai#2, and both chromosomes were preferentially transmitted between generations via female gametes. Evaluation of botanic and agronomic traits demonstrated that,compared with their parents, the new lines showed similar growth habits and plant type but differences in plant height, flowering date, and self-fertility. Cytological observations using different probes suggested that the double substitution lines showed nearly normal genetic behavior before and during meiosis. The novel substitution lines can potentially be used in wheat meiosis research and breeding programs. 展开更多
关键词 WHEAT double substitution lines Molecular markers Transmission rate of ALIEN chromosomes Genomic in SITU hybridization
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Evaluation matrix with the speed feature based on double inspiriting control lines 被引量:1
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作者 Weiwei Liu Chunsheng Shi Jing Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期962-970,共9页
Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to re... Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state (CSS) of the evaluated objects is analyzed based on double inspiriting control lines (DICLs), and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend (CST) in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature. 展开更多
关键词 double inspiriting control lines (DICLs) change speed state (CSS) change speed trend (CST) evaluation matrix
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Mesoscale and Microphysical Characteristics of a Double Rain Belt Event in South China on May 10–13,2022
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作者 郭照华 谌芸 +1 位作者 肖天贵 曾智琳 《Journal of Tropical Meteorology》 SCIE 2024年第1期61-75,共15页
A second rain belt sometimes occurs ahead of a frontal rain belt in the warm sector over coastal South China,leading to heavy precipitation.We examined the differences in the mesoscale characteristics and microphysics... A second rain belt sometimes occurs ahead of a frontal rain belt in the warm sector over coastal South China,leading to heavy precipitation.We examined the differences in the mesoscale characteristics and microphysics of the frontal and warm sector rain belts that occurred in South China on May 10–13,2022.The southern rain belt occurred in an environment with favorable mesoscale conditions but weak large-scale forcing.In contrast,the northern rain belt was related to low-level horizontal shear and the surface-level front.The interaction between the enhanced southeasterly winds and the rainfall-induced cold pool promoted the persistent growth of convection along the southern rain belt.The convective cell propagated east over the coastal area,where there was a large temperature gradient.The bow-shaped echo in this region may be closely related to the rear-inflow jet.By contrast,the initial convection of the northern rain belt was triggered along the front and the region of low-level horizontal shear,with mesoscale interactions between the enhanced warm-moist southeasterly airflow and the cold dome associated with the earlier rain.The terrain blocked the movement of the cold pool,resulting in the stagnation of the frontal convective cell at an early stage.Subsequently,a meso-γ-scale vortex formed during the rapid movement of the convective cell,corresponding to an enhancement of precipitation.The representative raindrop spectra for the southern rain belt were characterized by a greater number and higher density of raindrops than the northern rain belt,even though both resulted in comparable hourly rainfalls.These results help us better understand the characteristics of double rain belts over South China. 展开更多
关键词 double rain belts in South China mesoscale rainstorm cyclonic shear line cold pool bow-shaped echo microphysical characteristics
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Assembly Line Balancing Based on Double Chromosome Genetic Algorithm
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作者 刘俨后 左敦稳 张丹 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第6期622-628,共7页
Aiming at assembly line balancing problem,a double chromosome genetic algorithm(DCGA)is proposed to avoid trapping in local optimum,which is a disadvantage of standard genetic algorithm(SGA).In this algorithm,there ar... Aiming at assembly line balancing problem,a double chromosome genetic algorithm(DCGA)is proposed to avoid trapping in local optimum,which is a disadvantage of standard genetic algorithm(SGA).In this algorithm,there are two chromosomes of each individual,and the better one,regarded as dominant chromosome,determines the fitness.Dominant chromosome keeps excellent gene segments to speed up the convergence,and recessive chromosome maintains population diversity to get better global search ability to avoid local optimal solution.When the amounts of chromosomes are equal,the population size of DCGA is half that of SGA,which significantly reduces evolutionary time.Finally,the effectiveness is verified by experiments. 展开更多
关键词 double chromosome genetic algorithm assembly line balancing mathematical model global optimum
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Research into Freedom Surface Modeling System of Double Beta Spline in Space
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作者 Liu Xumin Department of Electronic Engineering, Jinzhou Teachers College, Liaoning 121000, P. R. China Xu Weixiang Automation Research Institute, Northern Jiaotong University, Beijing 100044, P. R. China Liu Xumin & Xu Weixiang Research into Freedom Sur 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第3期65-73,共9页
In this paper, we present the double Beta spline curved surface which is controlled by double parameters including the algorithm principles, the treatment of boundary conditions, the alternation of projection, the alg... In this paper, we present the double Beta spline curved surface which is controlled by double parameters including the algorithm principles, the treatment of boundary conditions, the alternation of projection, the algorithms of elimination hiddle line, the process to display and the primiples to produce the shaded curved surface. Based on all the above, a freedom surface modeling system (FSMS) is designed and some examples developed on FSMS are verified and analyzed. 展开更多
关键词 Curved surface modeling double Beta spline curved surface Elimination hiddle line Piece together Shaded curved surface.
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Process Analysis of Double Circuit Transmission Line Trip-out on the Same Tower Due to Lightning
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作者 DUAN Da-peng REN Zhi-gang WANG Peng YE Kuan CHANG Xiao-qi LI Wei 《高压电器》 CAS CSCD 北大核心 2011年第9期31-36,43,共7页
In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave th... In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave threat to the power grid security.The cause of the accident and the accident process were studied for the sake of further understanding of the impact of lightning on power grid.As an example,110 kV double circuit transmission line(Xilong-line) was analyzed.At first,the system topology was given.Through the analysis on relay protection actions and the fault recorder data,over voltage on the insulator strings was calculated.Based on the analysis and the calculation,accident cause and the process were presented respectively.Secondly,it comes to the conclusion that the lightning failure was caused by counterattack.The wave of the lightning over voltage would spread to the not grounded neutral point of the transformers,and make the neutral protective gap breakdown,then cause freewheeling with the frequency of 50 Hz.As results of the relay protection,the double circuit transmission line all tripped out.Finally,the causes of the accident were proposed that included terrain features,large corner towers,strong thunderstorm weather and poor grounded contact of the tower. 展开更多
关键词 double circuit transmission lines on the same tower lightning trip-out at the same time fault recorder over-voltage calculation lightning protection
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Fault location of two-parallel transmission line for double phase-to-earth fault using one-terminal data
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作者 张庆超 段晖 +1 位作者 耿超 宋文南 《Journal of Zhejiang University Science》 CSCD 2003年第5期520-525,共6页
An accurate algorithm for fault location of double phase-to-earth fault on transmission line of direct ground neutral system is presented. The algorithm, which employs the faulted phase network and zero-sequence netwo... An accurate algorithm for fault location of double phase-to-earth fault on transmission line of direct ground neutral system is presented. The algorithm, which employs the faulted phase network and zero-sequence network as fault-location model in which the source impedance at the remote end is not involved, ef-fectively eliminates the effect of load flow and fault resistance on the accuracy of fault location. The algorithm achieves accurate location by measuring only one local end data and is used in a procedure that provides automatic determination of faulted types and phases, and does not require the engineer to specify them. Simulation results showed the effectiveness of the algorithm under the condition of double phase-to-earth fault. 展开更多
关键词 Fault location Transmission line double phas e-to-earth fault
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A Novel Fault Location Algorithmfor Double-Circuit Transmission Lines based on Distributed Parameter
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作者 商立群 施围 《电工电能新技术》 CSCD 北大核心 2006年第1期13-16,20,共5页
Anewfault location algorithmfor double-circuit transmissionlines is described inthis paper.Theproposed method uses data extractedfromtwo ends of the transmissionlines andthus eliminates the effects ofthe source impeda... Anewfault location algorithmfor double-circuit transmissionlines is described inthis paper.Theproposed method uses data extractedfromtwo ends of the transmissionlines andthus eliminates the effects ofthe source impedance andthe fault resistance.The distributed parameter model and the modal transformationare also employed.Depending on modal transformation,the coupled equations of the lines are converted intodecoupled ones.Inthis way,the mutual coupling effects between adjacent circuits of the lines are eliminatedandtherefore an accurate fault location can be achieved.The proposed methodis tested via digital simulationusing EMTP in conjunction with MATLAB.The test results corroborate the high accuracy of the proposedmethod. 展开更多
关键词 双回路输电线路 节点数据 故障分析 分布参数
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Fault Locator Using Two-end Unsynchronized Measurements for UHV Series Compensated Double-circuit Lines
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作者 M. Fulczyk P. Balcerek +2 位作者 J. Izykowski E. Rosolowski M. M. Saha 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2523-2529,共7页
An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutin... An accurate fault location algorithm for double-circuit series compensated lines is presented.Use of two-end unsynchronized measurements of current and voltage signals is considered.The algorithm applies two subroutines,designated for locating faults on particular line sections,and additionally the procedure for selecting the valid subroutine.The subroutines are formulated with use of the generalized fault loop model and the distributed parameter line model is applied.Performed ATP-EMTP based evaluation has shown the validity of the derived fault location algorithm and its high accuracy. 展开更多
关键词 两端非同步测量法 串联补偿 线路故障 定位仪 ATP-EMTP
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The Optimizing Model and Its Solution for Making Train Working Graph with Computer on Separative Division of Double-Track Lines
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作者 Peng Qiyuan Ju Tingying(Department of Transportation Engineering),Soulhudest Jiaolong Universily,Chengdu 610031,China 《Journal of Modern Transportation》 1994年第2期181-188,共8页
The authoros specialize in the field of optunization and automatic programme oftrain working graph. In this peper, at frist, a mixed 0-1 integer progranimingmodel about this problem for duuble-track lines is set up, t... The authoros specialize in the field of optunization and automatic programme oftrain working graph. In this peper, at frist, a mixed 0-1 integer progranimingmodel about this problem for duuble-track lines is set up, then the principle andProcess of selution are stated, with an application exaiiiple put forward. 展开更多
关键词 train workins graph double-tracK line division mixed 0-1 mtegerprosrammins COMPUTER
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利用改良的CRISPR/Cas9n double nick系统构建DPF2基因敲除的人胰腺癌PANC-1细胞株
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作者 黄卫东 张文胜 +1 位作者 陈一帆 郭嘉义 《宁夏医科大学学报》 2023年第12期1189-1193,共5页
目的利用改良的CRISPR/Cas9n double nick系统构建DPF2基因敲除的PANC-1人胰腺癌细胞模型。方法设计两对靶向DPF2基因第四外显子上下游的单链向导RNA(single guide RNA,sgRNA),化学合成sgRNA寡核苷酸序列,并克隆至pGL3-U6-sgRNA-PGK-pur... 目的利用改良的CRISPR/Cas9n double nick系统构建DPF2基因敲除的PANC-1人胰腺癌细胞模型。方法设计两对靶向DPF2基因第四外显子上下游的单链向导RNA(single guide RNA,sgRNA),化学合成sgRNA寡核苷酸序列,并克隆至pGL3-U6-sgRNA-PGK-puromycin真核表达质粒中。将克隆正确的DPF2-sgRNA重组真核表达质粒与Cas9真核表达载体pST1374-N-NLS-flag-linker-Cas9共转染至PANC-1细胞中,通过嘌呤霉素和杀稻瘟菌素筛选阳性转染细胞,进一步通过有限稀释法筛选获得单克隆细胞株。提取细胞基因组DNA对敲除位点进行聚合酶链反应(PCR)鉴定和测序鉴定。Western blot检测细胞中DPF2蛋白表达情况。结果sgRNA成功插入pGL3-U6-sgRNA-PGK-puromycin中且序列正确。PCR扩增鉴定和测序结果表明,PANC-1细胞中一段包括完整第四外显子在内的长度为401 bp的DPF2基因片段被敲除。Western blot检测结果表明,DPF2基因敲除细胞中的DPF2蛋白表达缺失。结论通过改良的CRISPR/Cas9n double nick基因编辑系统成功构建DPF2基因敲除PANC-1稳定细胞株。 展开更多
关键词 DPF2基因 CRISPR/Cas9n double nike系统 基因敲除 PANC-1细胞株
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Study on dynamic optimization of the double railway suspended vehicle for automatic transportation in the welding shop 被引量:4
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作者 黄大巍 高秀华 +2 位作者 邢浩 刘宏学 韩彦和 《China Welding》 EI CAS 2007年第2期31-34,共4页
The 2DOF dynamic equations of the doable railway suspended vehicle for automatic transportation in the welding shop are established. The sensitivities are analyzed. The parameter design is researched in ADAMS in terms... The 2DOF dynamic equations of the doable railway suspended vehicle for automatic transportation in the welding shop are established. The sensitivities are analyzed. The parameter design is researched in ADAMS in terms of the inner railway radius, wheelbase, gauge, girder length of the doable railway suspended vehicle for automatic transportation in the welding product line. The mutual-restriction among the design variables is discussed and the selective ranges of the variables are confirmed. The result shows that the stability of the doable railway suspended vehicle for automatic transportation in the welding product line depends on parameters of the inner railway radius, wheelbase, gauge, girder length. The optimal results of the optimal objective and design variables have research significance for the virtual prototype of the doable suspension railway automation vehicle. The optimal results are input into the simulation model iteratively and the simulation results are fed back to the physical prototype. The veracity and reliability of peoformance forecast are improved so that the manufacture cost of the doable suspension railway automation vehicle is reduced significantly. 展开更多
关键词 welding product line double railway suspended vehicle dynamics optimization
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A G-band terahertz monolithic integrated amplifier in 0.5-μm InP double heterojunction bipolar transistor technology 被引量:2
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作者 李欧鹏 张勇 +4 位作者 徐锐敏 程伟 王元 牛斌 陆海燕 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期448-452,共5页
Design and characterization of a G-band(140–220 GHz) terahertz monolithic integrated circuit(TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm In Ga As/In P double heteroju... Design and characterization of a G-band(140–220 GHz) terahertz monolithic integrated circuit(TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm In Ga As/In P double heterojunction bipolar transistor(DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the In P substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140–190 GHz respectively. The saturation output powers are-2.688 dBm at 210 GHz and-2.88 dBm at 220 GHz,respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. 展开更多
关键词 terahertz amplifier InP double heterojunction bipolar transistor inverted microstrip line monolithic integrated circuit
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A New Type of Double-Lumen Catheter to Replace Current One in RCA 被引量:1
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作者 Yingfeng Xue Zhenguo Yu 《International Journal of Clinical Medicine》 2016年第9期620-627,共8页
Objective: To replace the peripheral venous puncture for blood sampling with taking blood samples extracorporally from arterial line before predilution during RCA-CRRT performed. Methods: A new type of double-lumen fe... Objective: To replace the peripheral venous puncture for blood sampling with taking blood samples extracorporally from arterial line before predilution during RCA-CRRT performed. Methods: A new type of double-lumen femoral catheter was used instead of the current tubes. The new type of double-lumen tube had a greater distance from the inner venous ports to the inner arterial ports than current tubes. The minimum distance from the venous port to the arterial port was greatly lengthened. Replacement solution contained citrate, zero Ca<sup>2+</sup>, zero bicarbonate, low Na<sup>+</sup>. Blood samples were synchronously collected from the arterial line before the infusion of citrate replacement fluid and from the peripheral vein. The iCa concentration data of two groups were analyzed to observe the difference between iCa concentration levels in the arterial line and in peripheral vein;the anticoagulant effect of RCA and possible complications were observed, such as bleeding, clottings and hypocalcaemia. Results: 28 times of RCA-CRRT were performed on17 AKI and CRF patients with active bleeding or at the high risk of bleeding;336 blood samples were collected. Statistics showed that the difference of iCa concentration between arterial line group and the peripheral vein group was not significant (P = 0.9), there is a high degree of similarity between the iCa concentration of arterial line blood and the peripheral venous blood. None of the patients developed citrate toxicity or metabolic alkalosis. None induced bleeding, or bleeding aggravated. No obvious clotting occurred. Systemic calcium concentration was achieved in the ideal range. Conclusion: In clinical practice, the data of iCa concentration from arterial line can be used to replace that from peripheral vein when the new type of double-lumen femoral catheter is placed in femoral vein. RCA-CRRT therapy is safe and effective. 展开更多
关键词 RCA-CRRT Ionized Calcium Arterial line Peripheral Vein New Type of double-Lumen Femoral Catheter
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基于小波包分解卷积神经网络的停运输电线路故障识别方法
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作者 王鑫明 王祥宇 +3 位作者 贾晓卜 张飞飞 李少博 胡永强 《电测与仪表》 北大核心 2025年第1期61-67,共7页
当输电线路处于热备用状态时,停运线路上仍可能发生短路故障,准确地判断停运线路的故障状态能有效地避免合闸到故障线路时对电力系统造成冲击并对故障的排除提供便利,因此有必要对停运输电线路进行故障识别。对于双回输电线路提出一种... 当输电线路处于热备用状态时,停运线路上仍可能发生短路故障,准确地判断停运线路的故障状态能有效地避免合闸到故障线路时对电力系统造成冲击并对故障的排除提供便利,因此有必要对停运输电线路进行故障识别。对于双回输电线路提出一种采用小波包分解生成的频谱图作为卷积神经网络(convolutional neural network,CNN)输入进行特征提取的停运线路故障识别方法。为减少人为提取特征产生的误差,首先对停运输电线路故障时三相电压暂态波形进行测量,采用小波包分解得到三相电压波形时频特性,最终通过CNN提取特征并进行故障分类。为验证该方法的故障识别效果,以河北省3条线路的实际数据为基础,在ATP-EMTP中建立500 kV同塔双回输电线路模型,为模拟现场各因素产生的误差在测得电压波形中加入10 dB高斯白噪声。结果表明,对热备用线路上故障状态识别准确率为99.98%,在一定程度上为停运线路的故障诊断及排除提供了参考。 展开更多
关键词 同塔双回输电线路 感应电压 小波包分解 时频分析 卷积神经网络 故障识别
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小净距盾构隧道开挖面稳定性研究
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作者 高琪 《城市轨道交通研究》 北大核心 2025年第1期103-107,共5页
[目的]确定双线小净距盾构隧道施工过程中维持掌子面稳定所需极限支护压力。[方法]综合利用数值模拟、理论解析和工程验证的方法对双线小净距盾构隧道开挖面稳定性开展研究。采用数值模拟对双线小净距盾构隧道掌子面失稳模式和极限支护... [目的]确定双线小净距盾构隧道施工过程中维持掌子面稳定所需极限支护压力。[方法]综合利用数值模拟、理论解析和工程验证的方法对双线小净距盾构隧道开挖面稳定性开展研究。采用数值模拟对双线小净距盾构隧道掌子面失稳模式和极限支护压力进行分析,基于数值模拟结果提出了双线盾构隧道开挖面失稳解析模型,并利用极限平衡理论推导出了维持掌子面稳定所需的极限支护压力。[结果及结论]小净距盾构隧道在施工过程中会形成联合土拱,联合土拱作用下,维持双线小净距隧道开挖面稳定所需的极限支护压力会显著增加。理论解析表明,当净距小于0.5D(D为隧道直径)时,极限支护压力随着净距增大而增大;当净距超过0.5D时,极限支护压力随着净距的增大而减小;当净距超过2.0D时,联合土拱无法形成,此时破坏模式与单洞隧道破坏模式相同,净距对极限支护压力不再产生影响。 展开更多
关键词 地铁 双线隧道 小净距 开挖面稳定性 极限支护压力
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新经纪体制:驻村工作队的嵌入路径与组织逻辑——基于湖北襄中镇的案例研究
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作者 魏来 陶珊珊 《南京农业大学学报(社会科学版)》 北大核心 2025年第1期115-127,共13页
派驻工作队是中国基层改革实践中极具特色的治理方式,既有研究深陷科层与非科层的运作逻辑之争,更值得关注的问题是,外生的临时组织如何完成其特定政策使命。文章借助襄中镇驻村工作队的深度个案,在经验与理论的互切中建构双线委托代理... 派驻工作队是中国基层改革实践中极具特色的治理方式,既有研究深陷科层与非科层的运作逻辑之争,更值得关注的问题是,外生的临时组织如何完成其特定政策使命。文章借助襄中镇驻村工作队的深度个案,在经验与理论的互切中建构双线委托代理下的新经纪体制分析框架,提出“发展型经纪”概念,并分析其运作机制和组织逻辑。研究发现,通过结构、关系和认知的多维嵌入,协作与补位的功能发挥,以及调适性治理的灵活探索,发展型经纪得以深入基层社会,并与常规组织相配合,推动重大政策的执行。文章揭示了发展型经纪在制度背景、组织功能与治理逻辑上的新特点,对于拓深国家经纪理论、理解中国基层治理和政策落实的组织创新及其实践优化,具有一定的意义。 展开更多
关键词 驻村工作队 发展型经纪 新经纪体制 双线委托代理
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接触网隧道吊柱智能化安装装备研制及工程实践应用
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作者 曹斐 《科学技术创新》 2025年第1期44-47,共4页
国内高速铁路的飞速发展,带动地方经济发展的同时也有效地促进了铁路建造技术质的飞跃。同时,随着智能建造理念的提出,有效地推动了建设行业智能装备、智能设备的投入应用。但当前高速铁路接触网工程在现场施工环节依然存在诸多施工效... 国内高速铁路的飞速发展,带动地方经济发展的同时也有效地促进了铁路建造技术质的飞跃。同时,随着智能建造理念的提出,有效地推动了建设行业智能装备、智能设备的投入应用。但当前高速铁路接触网工程在现场施工环节依然存在诸多施工效率低下、安全风险高等一些列问题,特别是现阶段高速铁路隧道断面越来越大,隧道内接触网吊柱安装高空作业风险隐患尤为关键。本文面向建设施工一线建设,通过对隧道内接触网吊柱智能化安装相关技术进行深入研究,完成适用于高速铁路隧道内接触网吊柱安装机械化、自动化安装装备的制造及工程实践应用。研究该装备的目标是开发基于视觉引导的高精度自动对位安装装备,完成大断面隧道内接触网吊柱安装的需要。 展开更多
关键词 双线隧道 接触网吊柱 机械化 自动化 自动对位
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考虑双线相互干涉的铁路项目施工组织研究
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作者 周亦威 杨烁 郭锴 《山东理工大学学报(自然科学版)》 CAS 2025年第1期52-59,共8页
针对线状活动铁路工程施工场景,在双线相互干涉条件下,基于线性计划方法,对双线的空间表达以施工区段为单位进行重构,建立时间-施工区段模型,考虑时间、空间、施工资源等约束,构建线路内部约束条件,再以线路内部约束为基础,建立线路间... 针对线状活动铁路工程施工场景,在双线相互干涉条件下,基于线性计划方法,对双线的空间表达以施工区段为单位进行重构,建立时间-施工区段模型,考虑时间、空间、施工资源等约束,构建线路内部约束条件,再以线路内部约束为基础,建立线路间约束条件。结合标准遗传算法,以各条线路各区段内施工资源配置情况为自变量,构建双线相互干涉条件下铁路工程施工进度计划工期优化算法,能够在算法中自动输出最优工期条件下的资源配置情况,根据算法输出的最优工期和资源配置情况制作对应的线性计划图。算例仿真结果表明,工期优化模型和算法能够高效获得最短工期下双线相互干涉的铁路项目施工进度计划,验证了本文模型的合理性和算法的有效性。 展开更多
关键词 铁路施工 进度管理 线性计划方法 遗传算法 双线相互干涉
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