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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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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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Development and Analysis of the Magnetic Circuit on Double-Radial Permanent Magnet and Salient-Pole Electromagnetic Hybrid Excitation Generator for Vehicles
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作者 Xueyi Zhang Qinjun Du +2 位作者 Jinbin Xu Yuzhen Zhao Shilun Ma 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第2期100-112,共13页
With the improvement of vehicles electrical equipment, the existing silicon rectification generator and permanent magnet generator cannot meet the requirement of the electric power consumption of the modern vehicles e... With the improvement of vehicles electrical equipment, the existing silicon rectification generator and permanent magnet generator cannot meet the requirement of the electric power consumption of the modern vehicles electrical equipment. It is di cult to adjust the air gap magnetic field of the permanent magnet generator. Consequently, the output voltage is not stable. The silicon rectifying generator has the problems of low e ciency and high failure rate.In order to solve these problems, a new type of hybrid excitation generator is developed in this paper. The developed hybrid excitation generator has a double-radial permanent magnet, a salient-pole electromagnetic combined rotor,and a fractional slot winding stator, where each rotor pole corresponds to 4.5 stator teeth. The equivalent magnetic circuit diagram of permanent magnet rotor and magnetic rotor is established. Magnetic field finite element analysis(FEA) software is used to conduct the modeling and simulation analysis on double-radial permanent magnet magnetic field, salient-pole electro-magnetic magnetic field and hybrid magnetic field. The magnetic flux density mold value diagram and vector diagram are obtained. The diagrams are used to verify the feasibility of this design. The designed electromagnetic coupling regulator controller can ensure the stable voltage export by changing the magnitude and direction of the excitation current to adjust the size of the air gap magnetic field. Therefore, the problem of output voltage instability in the wide speed range and wide load range of the hybrid excitation generator is solved. 展开更多
关键词 Vehicle Hybrid excitation GENERATOR double-radial permanent magnet Salient-pole ELECTROMAGNETIC ELECTROMAGNETIC coupling REGULATOR controller
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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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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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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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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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Research on Total Electric Field for DC Lines Converted from Double-Circuit AC Lines
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作者 Xiaoqian Ma Jiayu Lu +1 位作者 Kun He Wensheng Gao 《Energy and Power Engineering》 2017年第4期598-610,共13页
With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the c... With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes. 展开更多
关键词 DC lines Converted from AC lines Multi-Circuit DC LINE at same Tower pole Conductor BUNDLES Arrangement Scheme Total Electric Field Line-to-Ground Distance Corridor Width
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Establishment of the Eukaryotic Cell Lines for Inducible Control of SARS-CoV Nucleocapsid Gene Expression
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作者 Guo-hui CHANG Andrew Dividson +3 位作者 Lei LIN Matt Wilson Stuart G Siddell Qing-yu ZHU 《Virologica Sinica》 SCIE CAS CSCD 2010年第5期361-368,共8页
In order to establish the eukaryotic cell lines for inducible control of SARS-CoV nucleocapsid gene expression.The recombinant plasmid of pTRE-Tight-SARS-N was constructed by using the plasmid p8S as the PCR template ... In order to establish the eukaryotic cell lines for inducible control of SARS-CoV nucleocapsid gene expression.The recombinant plasmid of pTRE-Tight-SARS-N was constructed by using the plasmid p8S as the PCR template which contains a cDNA clone covering the nucleocapsid gene of SARS-CoV HKU-39449. Restriction enzymes digestion and sequence analysis indicated the recombinant plasmid of pTRE-Tight-SARS-N contained the nucleocapsid gene with the optimized nucleotide sequence which will improve the translation efficiency. Positive cell clones were selected by cotransfecting pTRE-Tight-SARS-N with the linear marker pPUR to BHK-21 Tet-on cells in the presence of puromycin. A set of double-stable eukaryotic cell lines (BHK-Tet-SARS-N) with inducible control of the SARS-CoV neucleocapsid gene expression was identified by using SDS-PAGE and Western-blot analysis. The expression of SARS-CoV nucleocapsid protein was tightly regulated by the varying concentration of doxcycline in the constructed double-stable cell line. The constructed BHK-Tet-SARS-N cell strains will facilitate the rescue of SARS-CoV in vitro and the further reverse genetic research of SARS-CoV. 展开更多
关键词 SARS-COV Nucleocapsid protein Inducible expression double stable cell lines
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Reducing Greenhouse Gas Emissions through Improving the Life Span of Wooden Power Electric Poles of Eucalyptus saligna
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作者 Joseph Voufo Zakari Yaou +3 位作者 Florent Biyeme Rolland Djomi Richard Dadji Metangmo Théodore Tchotang 《Modern Mechanical Engineering》 2022年第1期1-26,共26页
The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, mos... The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, most of the power line networks are made of wooden supports and according to the Cameroon energy distribution company, wooden poles represent 32% of the causes of death linked to the state of the network. The company’s 2019 annual report indicates that 40,000 wooden poles were in critical condition and should be replaced. A significant number of mechanical failures affecting these supports have been observed. For example, on the HVA/LV power line “D17 Nko- abang” in Yaoundé in Cameroon, less than three years old, 10 (ten) cases of poles falling and/or breaking, due to their mechanical loading, were observed over a period of fewer than nine months, causing an average service stoppage for more than 11 hours and affecting an average of 3280 customers. These incidents lead to questions about how the supports are dimensioned and what load capacities they are designed to support. The aim of this work is, therefore, to suggest a method of dimensioning wooden poles hence reducing green- house gas emissions due to the deforestation by reducing the number of woo- den poles at risk to be replaced on Cameroon’s electricity distribution network. And more specifically, to reduce the number of mechanical failures affecting the wooden supports observed by analyzing the current wooden supports with their loads and to make proposals for improving the actual dimensioning me- thods. From the study carried out, it appears that 449 out of 845 supports, i.e., 53% needed to be replaced or monitored because they support the nominal forces ranging from 85% to 150% of their admissible limit and proposals have been made to improve their dimensioning. 展开更多
关键词 Electrical Power Line Dimensioning Wooden pole Efforts on pole pole’s Height Method of Loading Overload Coefficients
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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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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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A New Principle of Fault Identification of on the Same Tower Based on Traveling Wave Reactive Powers
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作者 Hao Wu Ruikai Ye +2 位作者 Xingxing Dong Kunjian Yu Zhengwei Chang 《Journal of Power and Energy Engineering》 2019年第7期50-70,共21页
In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based ... In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based on the reactive powers of traveling wave is proposed. With the implementation of S-transform, the initial traveling wave reactive powers are calculated and the change characteristics of reactive power under different fault conditions are studied. The protection criterion is constructed by analyzing the ratio of the reactive powers of the same end on double-circuit transmission lines and the ratio of the reactive powers at both ends on the same line. According to the ratio of reactive power on the same side of the line and both ends of the same line, it is possible to identify whether the faults of the double-circuit line of the same tower occurred in or out of the protection zone. A large number of simulation results show that the protection performance is sensitive and reliable, and quick to respond. The criterion is simple and is basically not affected by fault initial angles, fault types, and transitional resistances. 展开更多
关键词 double-Circuit Transmission Line on the same TOWER TRAVELING Wave Reactive Power S-TRANSFORM Fault Identification
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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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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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Study on Galloping Stability Mechanism of Conductor and Its Application to Anti-Galloping of Transmission Lines 被引量:1
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作者 YouChuanyong 《Electricity》 2005年第1期26-30,共5页
Galloping of conductor is a major hazard to safe operation of transmission lines. This paper introduces the basic galloping stability mechanism of conductor, design method of anti-galloping and the application of anti... Galloping of conductor is a major hazard to safe operation of transmission lines. This paper introduces the basic galloping stability mechanism of conductor, design method of anti-galloping and the application of anti-galloping double pendulum and integral eccentric pendulum in China. Galloping stability mechanism of conductor was established based on vertical galloping mechanism developed by Den Hartog and torsional galloping mechanism developed by O. Nigel. A design method of anti-galloping was derived and anti-galloping double pendulum and integral eccentric pendulum were developed. Applications to several transmission lines including a 500 kV transmission line of large span indicated that they have played important roles in anti-galloping. 展开更多
关键词 galloping of conductor stability mechanism transmission line anti-galloping double pendulum integral eccentric pendulum
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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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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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The Measurement and Control of Diameter in Large-Scale Part Processing
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作者 ZHANG Guo-yu, XU Xi-ping, FU Xiu-hua, YANG Lin, LI Cheng -zhi (The Development Center of Science and Technology, Changchun University of Science and Technology, Changchun 130022, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期144-145,共2页
Based on laser-scanned measuring technology, a met ho d of on-line dynamic non-contact measurement and feedback control of processin g dimension, i.e. the double edges laser-scanned large diameter on-line dynami c mea... Based on laser-scanned measuring technology, a met ho d of on-line dynamic non-contact measurement and feedback control of processin g dimension, i.e. the double edges laser-scanned large diameter on-line dynami c measurement and control system is presented, which can be used to measure diam eter in large-scale machine part processing. In this paper, the working princip le, overall structure and microcomputer real-time control and data processing s ystem of the system are discussed in detail, the method of double edges scanned large diameter dimension measurement and control is theoretically analyzed, its possibility has been verified by experiments of lathing large diameters machine parts by a vertical lathe. The system adopts the measuring scheme of double edge s laser-scanned combined with grating displacement measurement. The two edges c haracteristic information of the measured diameter is given by the double edges laser-scanned measuring system, the non-contact measurement of large diameter dimension is realized to combine with the grating displacement measuring systems . The main controller gives out feedback control signal by means of measured res ults, and controls advance and retreat of lathe tool by the servo-control syste m of a vertical lathe to realize on-line dynamic non-contact measurement and c ontrol in processing. 展开更多
关键词 double edges laser-scanned on-line dynamic mea surement DIAMETER grating displacement measurement feedback control
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