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Fault Estimation for a Class of Markov Jump Piecewise-Affine Systems: Current Feedback Based Iterative Learning Approach
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作者 Yanzheng Zhu Nuo Xu +2 位作者 fen wu Xinkai Chen Donghua Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期418-429,共12页
In this paper, the issues of stochastic stability analysis and fault estimation are investigated for a class of continuoustime Markov jump piecewise-affine(PWA) systems against actuator and sensor faults. Firstly, a n... In this paper, the issues of stochastic stability analysis and fault estimation are investigated for a class of continuoustime Markov jump piecewise-affine(PWA) systems against actuator and sensor faults. Firstly, a novel mode-dependent PWA iterative learning observer with current feedback is designed to estimate the system states and faults, simultaneously, which contains both the previous iteration information and the current feedback mechanism. The auxiliary feedback channel optimizes the response speed of the observer, therefore the estimation error would converge to zero rapidly. Then, sufficient conditions for stochastic stability with guaranteed performance are demonstrated for the estimation error system, and the equivalence relations between the system information and the estimated information can be established via iterative accumulating representation.Finally, two illustrative examples containing a class of tunnel diode circuit systems are presented to fully demonstrate the effectiveness and superiority of the proposed iterative learning observer with current feedback. 展开更多
关键词 Current feedback fault estimation iterative learning observer Markov jump piecewise-affine system
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SHARP ESTIMATES OF QUASI-CONVEX MAPPINGS OF TYPE B AND ORDER α 被引量:1
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作者 刘名生 吴芬 杨燕 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1265-1276,共12页
In this paper, we first establish several sharp inequalities of homogeneous expansion for biholomorphic quasi-convex mappings of type B and order α on the unit ball E in a complex Banach space X by applying the metho... In this paper, we first establish several sharp inequalities of homogeneous expansion for biholomorphic quasi-convex mappings of type B and order α on the unit ball E in a complex Banach space X by applying the method and technique of complex analysis. Then, as the application of these sharp inequalities, we derive the sharp estimate of third homogeneous expansions for the above mappings defined on the unit polydisk U^n in C^n. 展开更多
关键词 quasi-convex MAPPINGS of TYPE B and order α INEQUALITIES of HOMOGENEOUS EXPANSIONS the SHARP estimate of third HOMOGENEOUS EXPANSIONS
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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes
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作者 fen wu Xin Li +1 位作者 Junbiao Chang Dachang Bai 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期420-425,共6页
Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes wi... Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and oxidant.The reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic amines.Notably,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent regioselectivity.The divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds cleavage.This protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis. 展开更多
关键词 PALLADIUM Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage
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Effects of spin-coating speed on the morphology and photovoltaic performance of the diketopyrrolopyrrole-based terpolymer 被引量:1
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作者 fen wu Rongyan Hou +2 位作者 Liang Yang Bin Zhao Songting Tan 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第4期466-471,共6页
Polymer solar cells(PSCs) were fabricated by combining a diketopyrrolopyrrole-based terpolymer(PTBT-HTID-DPP) as the electron donor, and [6,6]-phenyl C_(61) butyric acid methyl ester(PC_(61)BM) as the electron accepto... Polymer solar cells(PSCs) were fabricated by combining a diketopyrrolopyrrole-based terpolymer(PTBT-HTID-DPP) as the electron donor, and [6,6]-phenyl C_(61) butyric acid methyl ester(PC_(61)BM) as the electron acceptor, and the power conversion efficiency(PCE) of 4.31% has been achieved under AM 1.5 G(100 m W cm^(-2)) illumination condition via optimizing the polymer/PC_(61)BM ratio, the variety of solvent and the spin-coating speed. The impact of the spin-coating speed on the photovoltaic performance of the PSCs has been investigated by revealing the effects of the spin-coating speed on the morphology and the absorption spectra of the polymer/PC_(61)BM blend films. When the thickness of the blend films are adjusted by spin-coating a fixed concentration with different spin-coating speeds, the blend film prepared at a lower spin-coating speed shows a stronger absorption per unit thickness, and the correspond device shows higher IPCE value in the longer-wavelength region. Under the conditions of similar thickness, the blend film prepared at a lower spin-coating speed forms a more uniform microphase separation and smaller domain size which leads to a higher absorption intensity per unit thickness of the blend film in long wavenumber band, a larger short-circuit current density(J_(sc)) and a higher power conversion efficiency(PCE) of the PSC device. Noteworthily, it was found that spin-coating speed is not only a way to control the thickness of active layer but also an influencing factor on morphology and photovoltaic performance for the diketopyrrolopyrrole-based terpolymer. 展开更多
关键词 速度调整 光伏性能 聚吡咯 旋涂 形态 有源层厚度 功率转换效率 PSCs
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DNA-有机小分子复合结构的合成及应用研究
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作者 叶建涵 吴芬 +2 位作者 董原辰 徐立进 刘冬生 《高分子学报》 SCIE CAS CSCD 北大核心 2022年第12期1421-1428,共8页
探索并比较了DNA与有机小分子化合物在固相合成和液相偶联中的反应效率,利用DNA固相合成的方法高效的合成了多种DNA-有机小分子的复合结构,通过基质辅助激光解吸-飞行时间质谱(MALDI-TOF)对其结构和分子量进行了表征;并利用透射电子显... 探索并比较了DNA与有机小分子化合物在固相合成和液相偶联中的反应效率,利用DNA固相合成的方法高效的合成了多种DNA-有机小分子的复合结构,通过基质辅助激光解吸-飞行时间质谱(MALDI-TOF)对其结构和分子量进行了表征;并利用透射电子显微镜和动态光散射对DNA-芘复合结构在水相中的组装行为进行了初步的探索,其组装结构有望应用于药物的包裹释放研究. 展开更多
关键词 DNA 固相合成 液相偶联 自组装
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The investigation of the stability of DNA-b-PPO vesicles formed through frame guided assembly
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作者 Bo Bian Yi-Yang Zhang +5 位作者 Yuan-Chen Dong fen wu Chao Wang Shuo Wang Yun Xu Dong-Sheng Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第12期1568-1571,共4页
Frame-guided assembly is a novel assembly method which can control the shape and size of vesicles accurately. It has been reported that the DNA-b-PPO vesicles could be stable over two weeks. In this communication we h... Frame-guided assembly is a novel assembly method which can control the shape and size of vesicles accurately. It has been reported that the DNA-b-PPO vesicles could be stable over two weeks. In this communication we have introduced restriction sites of EcoR1 in the interior DNA scaffold to the formed vesicles in order to further study their stability. Dynamic light scattering(DLS), transmission electron microscope(TEM) and fluorescence spectrum were used to characterize the digestion process. The final results revealed that the vesicles were still stable even after two weeks cultivated with EcoR1, which suggests potential in future biological applications. 展开更多
关键词 frame-guided ASSEMBLY vesicles stability RESTRICTION sites EcoR1
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饮用水砷暴露与QT间期延长:砷对健康影响的纵向研究结果
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作者 Yu Chen fen wu +14 位作者 Faruque Parvez Alauddin Ahmed Mahbub Eunus Tyler R.McClintock Tazul Islam Patwary Tariqul Islam Anajan Kumar Ghosal Shahidul Islam Rabiul Hasan Diane Levy Golam Sarwar Vesna Slavkovich Alexander van Geen Joseph H.Graziano Habibul Ahsan 《环境与职业医学》 CAS 北大核心 2013年第7期550-550,共1页
[背景]饮用水砷暴露与心脏疾病相关联,然而内在的机制尚不明确。[目的]评估饮用水砷暴露史与心率校正的QT(QTc)、PR和QRS间期延长之间的关联。[方法]从砷对健康影响的纵向研究中选择1715名基线入组的参加者进行研究。评估2005—2010年间... [背景]饮用水砷暴露与心脏疾病相关联,然而内在的机制尚不明确。[目的]评估饮用水砷暴露史与心率校正的QT(QTc)、PR和QRS间期延长之间的关联。[方法]从砷对健康影响的纵向研究中选择1715名基线入组的参加者进行研究。评估2005—2010年间,井水中的砷暴露和尿液样本与心电图(ECG)参数的关联,自基线开始平均跟踪了5.9年。[结果]QTc延长的定义为男性QTc≥450ms,女性≥460ms。井水中砷每增加1-SD(108.7μg/L),QTc延长的调整比值比(OR)为1.17(95%CI:1.01~1.35)。正相关仅限于女性,基线时井水和尿液中的砷每增加1-SD,女性调整后ORs分别比为1.24(95%CI:1.05~1.47)和1.24(95%CI:1.01~1.53);与之相比,男性调整后ORs分别为0.99(95%CI:0.73~1.33)和0.86(95%CI:0.49~1.51)。基线时井水砷或尿砷与女性或男性的PR或QRS间期延长之间无明显的关联。[结论]长期饮用水砷暴露(平均95μg/L,全距为0.1~790μg/L)与女性之后的QT间期延长相关联。在今后的纵向研究中,ECG的反复测量对于评估暴露变化的影响将具有重要意义。 展开更多
关键词 孟加拉 心血管疾病 心电图 心率校正的QT间期 环境暴露
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An Overview of Self-Assembly and Morphological Regulation of Amphiphilic DNA Organic Hybrids
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作者 fen wu Yiyang Zhang Zhongqiang Yang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2015年第5期511-516,共6页
In this review,we summarized the assembly behavior of DNA organic hybrids and listed reported strategies of tuning the morphology of assemblies.The self-assembly and morphological regulation of DNA organic hybrids pro... In this review,we summarized the assembly behavior of DNA organic hybrids and listed reported strategies of tuning the morphology of assemblies.The self-assembly and morphological regulation of DNA organic hybrids provide an effective way to construct functional nanostructures with potential applications in nanomaterials,drug delivery and tissue engineering.The future directions are discussed. 展开更多
关键词 DNA amphiphiles SELF-ASSEMBLY MORPHOLOGY REGULATION
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