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Specific emitter identification based on frequency and amplitude of the signal kurtosis
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作者 ZHAO Yurui WANG Xiang +1 位作者 SUN Liting HUANG Zhitao 《Journal of Systems Engineering and Electronics》 2025年第2期333-343,共11页
Extensive experiments suggest that kurtosis-based fingerprint features are effective for specific emitter identification (SEI). Nevertheless, the lack of mechanistic explanation restricts the use of fingerprint featur... Extensive experiments suggest that kurtosis-based fingerprint features are effective for specific emitter identification (SEI). Nevertheless, the lack of mechanistic explanation restricts the use of fingerprint features to a data-driven technique and fur-ther reduces the adaptability of the technique to other datasets. To address this issue, the mechanism how the phase noise of high-frequency oscillators and the nonlinearity of power ampli-fiers affect the kurtosis of communication signals is investigated. Mathematical models are derived for intentional modulation (IM) and unintentional modulation (UIM). Analysis indicates that the phase noise of high-frequency oscillators and the nonlinearity of power amplifiers affect the kurtosis frequency and amplitude, respectively. A novel SEI method based on frequency and ampli-tude of the signal kurtosis (FA-SK) is further proposed. Simula-tion and real-world experiments validate theoretical analysis and also confirm the efficiency and effectiveness of the proposed method. 展开更多
关键词 communication emitter fingerprint feature KURTOSIS unintentional modulation(UIM) specific emitter identification(SEI).
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RFFsNet-SEI:a multidimensional balanced-RFFs deep neural network framework for specific emitter identification 被引量:1
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作者 FAN Rong SI Chengke +1 位作者 HAN Yi WAN Qun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期558-574,F0002,共18页
Existing specific emitter identification(SEI)methods based on hand-crafted features have drawbacks of losing feature information and involving multiple processing stages,which reduce the identification accuracy of emi... Existing specific emitter identification(SEI)methods based on hand-crafted features have drawbacks of losing feature information and involving multiple processing stages,which reduce the identification accuracy of emitters and complicate the procedures of identification.In this paper,we propose a deep SEI approach via multidimensional feature extraction for radio frequency fingerprints(RFFs),namely,RFFsNet-SEI.Particularly,we extract multidimensional physical RFFs from the received signal by virtue of variational mode decomposition(VMD)and Hilbert transform(HT).The physical RFFs and I-Q data are formed into the balanced-RFFs,which are then used to train RFFsNet-SEI.As introducing model-aided RFFs into neural network,the hybrid-driven scheme including physical features and I-Q data is constructed.It improves physical interpretability of RFFsNet-SEI.Meanwhile,since RFFsNet-SEI identifies individual of emitters from received raw data in end-to-end,it accelerates SEI implementation and simplifies procedures of identification.Moreover,as the temporal features and spectral features of the received signal are both extracted by RFFsNet-SEI,identification accuracy is improved.Finally,we compare RFFsNet-SEI with the counterparts in terms of identification accuracy,computational complexity,and prediction speed.Experimental results illustrate that the proposed method outperforms the counterparts on the basis of simulation dataset and real dataset collected in the anechoic chamber. 展开更多
关键词 specific emitter identification(SEI) deep learning(DL) radio frequency fingerprint(RFF) multidimensional feature extraction(MFE) variational mode decomposition(VMD)
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A Trace-state Based Approach to Specification and Design of Parallel Programs
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作者 He Jifeng Oxford University Computing LaboratoryProgramming Research Group Parks Road, Oxford OXl 3QD, England 《计算机工程》 CAS CSCD 北大核心 1996年第S1期91-105,共15页
In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal sys... In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal system based on that model to achieve hierarchical and modular development and verification methods. Anumber of refinement rules are used to decompose the specification into smaller ones and calculate program fromthe 展开更多
关键词 COMM A Trace-state Based Approach to specification and Design of Parallel Programs
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关于弱Specification性质的一个注记 被引量:3
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作者 吴新星 《数学物理学报(A辑)》 CSCD 北大核心 2017年第4期601-606,共6页
该文证明具有弱specification性质的系统在其测度中心的限制系统也具有弱specification性质,并且其逆不真.作为推论得到在未有满射的假设下,弱specification性质蕴含渐近平均跟踪性质.最后证明具有弱specification性质的满射系统是一致... 该文证明具有弱specification性质的系统在其测度中心的限制系统也具有弱specification性质,并且其逆不真.作为推论得到在未有满射的假设下,弱specification性质蕴含渐近平均跟踪性质.最后证明具有弱specification性质的满射系统是一致分布混沌的. 展开更多
关键词 测度中心 specification 渐近平均跟踪性质 分布混沌
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弱Specification和逆极限空间上移位映射(英文) 被引量:2
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作者 顾荣宝 《安徽大学学报(自然科学版)》 CAS 1998年第3期18-22,共5页
对度量空间上连续自映射引进弱Specification概念,研究了它与浑沌和拓扑熵的联系,此外还讨论了逆极限空间上移位映射的弱Specification性质。
关键词 specificATION 逆极限空间 移位映射 度量空间
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连续映射的弱specification性质与混沌
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作者 乔宗敏 朱夜明 顾荣宝 《合肥工业大学学报(自然科学版)》 CAS CSCD 2004年第9期1066-1069,共4页
specification性质是一种重要的动力性质,对连续的区间映射和树映射,该性质与拓扑混合等价。对紧致度量空间,满足POTP性质的拓扑混合映射具有specification性质。文章对紧致度量空间上连续自映射,研究了弱specification性质与各种混沌... specification性质是一种重要的动力性质,对连续的区间映射和树映射,该性质与拓扑混合等价。对紧致度量空间,满足POTP性质的拓扑混合映射具有specification性质。文章对紧致度量空间上连续自映射,研究了弱specification性质与各种混沌之间的关系,证明了具有弱specification性质的系统是Li-Yorke意义下混沌的,是Ruelle-Takens意义下混沌的,是处处混沌的,并且具有性质P。 展开更多
关键词 连续自映射 specification 混沌
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弱Specification性质与不变概率测度
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作者 乔宗敏 顾荣宝 《安徽大学学报(自然科学版)》 CAS 2004年第5期8-10,共3页
对紧致度量空间上连续自映射,研究了弱Specification性质与不变概率测度之间的关系,证明了具有弱Specification性质的系统一定存在f:X→X的不变概率测度m,使得Suppm=X,并且f:X→X有满测度中心,即M(f)=X.
关键词 specification性质 不变概率测度 连续自映射 紧致度量空间
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弱Specification和伪移位不变集(英文)
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作者 顾荣宝 《安徽大学学报(自然科学版)》 CAS 2002年第3期1-4,共4页
研究了弱Specification性质与紧致度量空间上连续映射的伪移位不变集的联系 ,得到的主要结果是 :设f∶X→X是紧致度量空间连续自映射 ,若f具有弱Specification性质 ,则存在正整数M ,使得fM具有伪移位不变集。
关键词 紧致度量空间 连续映射 specification 伪移位不变集 连续自映射
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逐点回归映射与弱Specification(英文) 被引量:1
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作者 顾荣宝 朱夜明 《安徽大学学报(自然科学版)》 CAS 2000年第1期1-5,共5页
重点证明了紧致度量空间上的逐点回归映射不满足弱Specification性质。
关键词 度量空间 连续映射 逐点回归
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高致病性猪繁殖与呼吸综合征病毒strand-specific荧光定量RT-PCR检测方法的建立 被引量:1
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作者 杨莘 周艳君 +3 位作者 单同领 姜一峰 童武 童光志 《中国预防兽医学报》 CAS CSCD 北大核心 2014年第11期872-876,共5页
为了解高致病性猪繁殖与呼吸综合征病毒(PRRSV)的复制和转录机制,准确定量其在复制过程中基因组不同类型RNA(v RNA和c RNA)的含量,本研究根据PRRSV基因组Nsp12基因设计含有链特异性标签的特异性引物,建立了一种针对病毒基因组不同链RNA... 为了解高致病性猪繁殖与呼吸综合征病毒(PRRSV)的复制和转录机制,准确定量其在复制过程中基因组不同类型RNA(v RNA和c RNA)的含量,本研究根据PRRSV基因组Nsp12基因设计含有链特异性标签的特异性引物,建立了一种针对病毒基因组不同链RNA的strand-specific荧光定量RT-PCR方法。结果表明,以重组质粒标准品构建的标准曲线在101拷贝/μL^107拷贝/μL范围内具有良好的线性关系,对v RNA和c RNA的检测下限为7.40拷贝/μL和6.52拷贝/μL,能够特异性的区分病毒复制过程中产生的v RNA链和c RNA链,具有很高的特异性、灵敏性和重复性。HP-PRRSV感染MARC-145细胞后不同时间段检测v RNA和c RNA含量显示,病毒不同链RNA含量在感染过程中持续增加,v RNA和c RNA含量在感染后24 h约为7.0×107拷贝/μL和7.2×106拷贝/μL。本研究建立的方法可以用于区分和定量PRRSV在复制过程中产生的不同链RNA,为研究病毒的复制和致病机理提供了一种有效的检测手段。 展开更多
关键词 猪繁殖与呼吸综合征病毒 strand-specific荧光定量RT-PCR 不同链RNA
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载体表达的siRNA分子对小鼠巨噬细胞galactose-specific lectin基因表达的抑制作用
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作者 葛阳春 王远志 +2 位作者 陈创夫 杜军伟 胡圣伟 《中国人兽共患病学报》 CAS CSCD 北大核心 2010年第5期467-470,474,共5页
目的构建小鼠巨噬细胞半乳糖特异性凝集素(GSL)靶向的RNAi质粒载体,研究其对小鼠和巨噬细胞GSL基因表达的沉默作用。方法根据GSL核苷酸序列,合成3条特异性双链小干扰RNA(siRNA)分子,退火形成双链,分别连接到RNAi-Readyp SIREN-RetroQ-Zs... 目的构建小鼠巨噬细胞半乳糖特异性凝集素(GSL)靶向的RNAi质粒载体,研究其对小鼠和巨噬细胞GSL基因表达的沉默作用。方法根据GSL核苷酸序列,合成3条特异性双链小干扰RNA(siRNA)分子,退火形成双链,分别连接到RNAi-Readyp SIREN-RetroQ-ZsGreen Vector,转化大肠杆菌得到阳性克隆,经测序鉴定确认siRNA载体构建成功后,转染小鼠巨噬细胞RAW264.7及尾静脉注射BALB/c小鼠,应用实时定量PCR和免疫组化法评价siRNA载体对小鼠和巨噬细胞GSL基因表达的抑制作用。结果 siRNA载体对小鼠体内GSL基因的抑制率为84-96%,对巨噬细胞GSL基因的抑制率可达61.98%~83.02%。结论构建的siRNA载体能有效抑制目的基因在体内外的表达,该结果为分析半乳糖特异性凝集素在布鲁氏菌侵染过程中的功能奠定了基础。 展开更多
关键词 RNAI 半乳糖特异性凝集素 巨噬细胞RAW264.7 小鼠
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为SOFL Specification自动生成消息序列(MSC)
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作者 王浩 《计算机工程与应用》 CSCD 北大核心 2006年第16期114-117,共4页
形式化方法以其精确的描述能力,可验证性,和自动化潜力而得到了人们的关注。特别是在一些对安全性要求非常高的领域,已经有了很多成功的案例。但他始终没有在业界得到推广。原因之一就是基于数学符号的形式化语法十分晦涩难懂,这给开发... 形式化方法以其精确的描述能力,可验证性,和自动化潜力而得到了人们的关注。特别是在一些对安全性要求非常高的领域,已经有了很多成功的案例。但他始终没有在业界得到推广。原因之一就是基于数学符号的形式化语法十分晦涩难懂,这给开发人员之间,开发人员和客户之间的交流造成了巨大的障碍。我们认为要解决这一问题,就需要为形式化规范提供更直观,更为大家所熟悉的行为表现方式。文章介绍如何自动生成MSC(messagesequencechart)来描述SOFL(StructuredObjectorientedFormalLanguage)[12]specification的行为。通过用MSC来动态模拟规范的行为的执行过程,可以很好地帮助人们理解规范内容,这对于规范校验(specificationvalidation)有重要的意义。此外,我们为支持这一MSC自动生成过程编写的一款工具原形,也会在文中作简要介绍。 展开更多
关键词 形式化方法 SOFL MSC 模拟 规范校验
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具有specification性质的连续流
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作者 张刚 卢占会 朱玉峻 《华北电力大学学报(自然科学版)》 CAS 北大核心 2003年第6期100-103,共4页
研究了具有specification性质连续流的动力性质。主要结论是:(1)具有specmcation性质的连续流是混沌的,且其拓扑熵大于零;(2)specmcation性质在扭扩及逆极限下是不变的。
关键词 混沌 specification性质 连续流 逆极限
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Effects of CMV Enhancer on Activity and Specificity of Bovine MyoG Gene Promoter 被引量:3
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作者 Wang Xin Lu Ming +1 位作者 Feng Lin-he Yan Yun-qin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第4期34-38,共5页
Connected a segment of CMV enhancer to the front of MyoG gene promoter and then constructed the corresponding dual luciferase expression vector pGL3-CMV-MyoGpro. We set four eukaryotic expression vectors including pGL... Connected a segment of CMV enhancer to the front of MyoG gene promoter and then constructed the corresponding dual luciferase expression vector pGL3-CMV-MyoGpro. We set four eukaryotic expression vectors including pGL3-CMV, pGL3MyoGpro, pGL3-CMV-MyoGpro, and pGL3-Basic which contained CMV promoter, MyoG promoter, CMV-MyoG synthesis promoter, and a promoterless negative control, respectively. Then the four vectors and internal control Renilla luciferase report gene vector phRL-TK were transfected into bovine skeletal muscle satellite cells, mouse C2C12 cells and bovine fetal fibroblast cells to detect the promoter activity with dual luciferase report system. The results showed that CMV enhancer could significantly improve the transcription activity of bovine MyoG gene promoter in muscle satellite cells and mouse C2C12 cells, and it had certain specificity. This study provided experimental materials for increasing the high expression of exogenous gene in bovine muscle cells, and also laid the molecular theoretical basis for obtaining the high specific promoter of bovine muscle and the transgenic beef cattle. 展开更多
关键词 CMV enhancer MyoG promoter dual luciferase report gene assay muscle specific
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Equal perimeter yield criterion and its specific plastic work rate: Development, validation and application 被引量:1
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作者 章顺虎 赵德文 陈晓东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4137-4145,共9页
In order to overcome the nonlinearity of Mises criterion, a new linear yield criterion with a dodecagon shape of the same perimeter as Mises criterion was derived by means of geometrical analysis. Its specific plastic... In order to overcome the nonlinearity of Mises criterion, a new linear yield criterion with a dodecagon shape of the same perimeter as Mises criterion was derived by means of geometrical analysis. Its specific plastic work rate expressed as a linear function of the yield stress, the maximum and minimum strains was also deduced and compared with that of Mises criterion. The physical meaning of the proposed yield criterion is that yielding of materials begins when the shear yield stress τs reaches the magnitude of 0.594σs. By introducing the Lode parameter, validation of evolution expressions of the proposed yield criterion with those based on Tresca, Mises and TSS criteria as well as available classical yield experimental results of various metals shows that the present results intersect with Mises results and coincide well with experimental data. Moreover, further application to the limit analysis of circle plate as an example is performed to demonstrate the effectiveness of the proposed yield criterion, and the subsequent comparison of limit loads with the Tresca analytical solutions and Mises numerical results shows that the present results are higher than the Tresca analytical results, and are in good agreement with the Mises numerical results. 展开更多
关键词 EP yield CRITERION specific PLASTIC WORK RATE circ
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Inhibitory effect of ammonia nitrogen on specific methanogenic activity of anaerobic granular sludge 被引量:6
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作者 周洪波 邱冠周 《Journal of Central South University of Technology》 EI 2006年第1期63-67,共5页
A series of batch experiments were conducted in 125 mL serum bottles to assess the toxicity of different concentrations of ammonia nitrogen to the specific methanogenic activity of anaerobic granular sludge from upflo... A series of batch experiments were conducted in 125 mL serum bottles to assess the toxicity of different concentrations of ammonia nitrogen to the specific methanogenic activity of anaerobic granular sludge from upflow anaerobic sludge bed(UASB) and expanded granular sludge bed(EGSB) reactors. The effects of pH value and temperature on toxicity of ammonia nitrogen to anaerobes were investigated. The results show that the specific methanogenic activity of anaerobic granular sludge suffers inhibition from ammonia nitrogen, the concentrations of ammonia nitrogen that produce 50 % inhibition of specific methanogenic activity for sludge from UASB and EGSB reactor are 2.35 and 2.75 g/L, respectively. Hydrogen utilizing methanogens suffers less inhibition from ammonia mtrogen than that of acetate utilizing methanogens. Hydrogen-producing acetogens that utilize propionate and butyrate as substrates suffer serious inhibition from ammonia nitrogen. The toxicity of ammonia nitrogen to anaerobic granular sludge enhances when pH value and temperature increase. Anaerobic granular sludge can bear higher concentrations of ammonia nitrogen after being acclimated by ammonia nitrogen for 7 d. 展开更多
关键词 ammonia nitrogen TOXICITY anaerobic granular sludge specific methanogenic activity
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Statistical analysis of pressure fluctuations during unsteady flow for low-specific-speed centrifugal pumps 被引量:3
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作者 裴吉 王文杰 袁寿其 《Journal of Central South University》 SCIE EI CAS 2014年第3期1017-1024,共8页
A three-dimensional transient numerical simulation was conducted to study the pressure fluctuations in low-specific-speed centrifugal pumps. The characteristics of the inner flow were investigated using the SST k-ω t... A three-dimensional transient numerical simulation was conducted to study the pressure fluctuations in low-specific-speed centrifugal pumps. The characteristics of the inner flow were investigated using the SST k-ω turbulence model. The distributions of pressure fluctuations in the impeller and the volute were recorded, and the pressure fluctuation intensity was analyzed comprehensively, at the design condition, using statistical methods. The results show that the pressure fluctuation intensity increases along the impeller streamline from the leading edge to the trailing edge. In the impeller passage, the intensity near the shroud is much higher than that near the hub at thc inlet. However, the intensity at the middle passage is almost equal to the intensity at the outlet. The pressure fluctuation intensity is the highest at the trailing edge on the pressure side and near the tongue because of the rotor-stator interaction. The distribution of pressure fluctuation intensity is symmetrical in the axial cross sections of the volute channel. However, this intensity decreases with increasing radial distance. Hence, the pressure fluctuation intensity can be reduced by modifying the geometry of the leading edge in the impeller and the tongue in the volute. 展开更多
关键词 TRANSIENT pressure fluctuation intensity STATISTICS low specific speed centrifugal pump
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Specific energy optimization in sawing of rocks using Taguchi approach 被引量:2
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作者 Izzet Karakurt 《Journal of Central South University》 SCIE EI CAS 2014年第1期365-372,共8页
This work aims at selecting optimal operating variables to obtain the minimum specific energy(SE) in sawing of rocks.A particular granite was sampled and sawn by a fully automated circular diamond sawblades.The periph... This work aims at selecting optimal operating variables to obtain the minimum specific energy(SE) in sawing of rocks.A particular granite was sampled and sawn by a fully automated circular diamond sawblades.The peripheral speed,the traverse speed,the cut depth and the flow rate of cooling fluid were selected as the operating variables.Taguchi approach was adopted as a statistical design of experimental technique for optimization studies.The results were evaluated based on the analysis of variance and signal-to-noise ratio(S/N ratio).Statistically significant operating variables and their percentage contribution to the process were also determined.Additionally,a statistical model was developed to demonstrate the relationship between SE and operating variables using regression analysis and the model was then verified.It was found that the optimal combination of operating variables for minimum SE is the peripheral speed of 25 m/s,the traverse speed of 70 cm/min,the cut depth of 2 cm and the flow rate of cooling fluid of 100 mL/s.The cut depth and traverse speed were statistically determined as the significant operating variables affecting the SE,respectively.Furthermore,the regression model results reveal that the predictive model has a high applicability for practical applications. 展开更多
关键词 circular diamond sawblades GRANITE specific energy Taguchi approach
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Dynamic Output Feedback Control Synthesis with Mixed Frequency Small Gain Specifications 被引量:4
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作者 ZHANG Xiao-Ni YANG Guang-Hong 《自动化学报》 EI CSCD 北大核心 2008年第5期551-557,共7页
This paper is concerned with the control synthesis problem via dynamic output feedback for linear continuous-time systems with mixed frequency small gain specifications.A new method for designing dynamic output feedba... This paper is concerned with the control synthesis problem via dynamic output feedback for linear continuous-time systems with mixed frequency small gain specifications.A new method for designing dynamic output feedback controllers is presented such that the resulting closed-loop systems are asymptotically stable and meet the requirements of small gain specifications in both finite frequency ranges and the entire frequency range.The design conditions are given in terms of solutions to a set of linear matrix inequalities(LMIs).Finally,a numerical example is given to illustrate the design procedure and the advantage of the proposed method in comparison with the existing one. 展开更多
关键词 Mixed frequency small gain specification multi-objective control
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Characterization of an Organ Specific and Pathogen Responsive CC-NBS-LRR Gene from Cotton(Gossypium hirsutum L.) 被引量:3
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作者 ZHANG Bao-long,NI Wan-chao,YANG Yu-wen,SHEN Xin-lian(Institute of Agro-biotechnology,Jiangsu Academy of Agricultural Sciences,Zhongling Street 50,Nanjing 210014,China) 《棉花学报》 CSCD 北大核心 2008年第S1期74-,共1页
Cotton diseases represent a major challenge to cotton growth.Cloning of a cotton pathogen response gene and promoter is of great importance to improve disease resistance.In this study,a
关键词 LRR NBS Characterization of an Organ specific and Pathogen Responsive CC-NBS-LRR Gene from Cotton CC
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