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Robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels

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Chinese Journal of Aeronautics 2014年第1期27卷 65-75页

作者： niu Erzhuo Wang qing Dong Chaoyang School of Automation Science and Electrical Engineering Beihang University School of Aeronautical Science and Engineering Beihang University

The observer-based robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels and norm bounded modeling uncertainties are addressed. The network of unmanned vehicles is modeled as a discrete-time uncertain Markovian jump system. Based on the model, a residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of linear matrix inequality. Furthermore, a time domain optimization approach is proposed to improve the performance of the fault detection system. The problem of detecting small faults can be formulated as an optimization problem and its solution is given. For preventing false alarms, a new adaptive threshold function is established. The combined fault detection and optimization algorithm and the adaptive threshold are then applied to a network of highly maneuverable technology vehicles to illustrate the effective- ness of the orooosed aooroach.

关键词： Fault detection andoptimization Imperfect communicationchannel Network Uncertainty Unmanned vehicle

Internal Conversion Process of Chlorophyll a in Solvents in Femtosecond Pump-Probe Laser Fields

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Chinese Journal of Chemical Physics 2008年第3期21卷 211-216页

作者： Kai niu Li-qing Dong Shu-lin Cong Department of Physics Dalian University of Technology Dalian 116024 China

The internal conversion （IC） processes of chlorophyll a （chl-a） in solvents are studied based on the reduced density matrix theory. The IC times can be obtained by simulating the experimental fluorescence depletion spectra （FDS）. The calculated IC times of chl-a in ethyl acetate, tetrahydrofuran and dimethyl formamide are 141, 147, and 241 fs, respectively. The oscillation feature of the FDS results from the forward and backward transfer of the population between coupled electronic states. The effects of diabatic coupling between two electronic states on the IC time and the FDS are described. The influence of molecule-reservoir coupling on the IC time is also investigated.

关键词： Fluorescence depletion spectrum Internal conversion Reduced density matrix

Morphology, crystal structure and hydration of calcined and modified anhydrite

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 1028-1032页

作者： Xiao-qing niu Ji-chun Chen School of Urban Construction Huazhong University of Science and Technology Wuchang Branch

The effects of calcination and modification on the morphology （shapes and textures） and crystal structure of anhydrite powders were studied. The results show that, calcination at 100℃ causes anhydrite to disintegrate into smaller crystals, accompanied by a slight in- crease in d-spacing. Without calcination and modification, the solidification time and curing time of anhydrite are 15 and 77 h, respectively. After the treatment, however, the solidification time and curing time are shortened significantly to 9.5 and 14 rain, respectively. The com- pressive and flexural strengths of hydration products made from the treated anhydrite reach 10.2 and 2.0 MPa, respectively. The much shorter solidification and curing time make it possible to use anhydrite as a building and construction material.

关键词： anhydrite morphology crystal structure curing hydration calcination modification

Systematics on production of superheavy nuclei Z=119-122 in fusion-evaporation reactions

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Nuclear Science and Techniques 2021年第10期32卷 59-71页

作者： Fei niu Peng-Hui Chen Zhao-qing Feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510640China College of Electrical Energy and Power Engineering Yangzhou UniversityYangzhou 225000China

The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system *** Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear *** production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from *** evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically *** combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?*** obtained that the production cross sections sensitively depend on the neutron richness of the reaction *** structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.

关键词： Dinuclear system model Fusion-evaporation reactions Superheavy nuclei Cross sections

Nitric Oxide Regulates Dark-Induced Leaf Senescence Through EIN2 in Arabidopsis

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Journal of Integrative Plant Biology 2012年第8期54卷 516-525页

作者： Yun-Han niu Fang-qing Guo The National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research(Shanghai) Institute of Plant Physiology&EcologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesShanghai 200032China

The nitric oxide （NO）-deficient mutant nosllnoal exhibited an early leaf senescence phenotype. ETHY- LENE INSENSITIVE 2 （EIN2） was previously reported to function as a positive regulator of ethylene- induced senescence. The aim of this study was to address the question of how NO interacts with ethylene to regulate leaf senescence by characterizing the double mutant ein2-1 nosllnoal （Arabidopsis thaliana）. Double mutant analysis revealed that the nosllnoal-mediated, dark-induced early senescence phenotype was suppressed by mutations in EIN2, suggesting that EIN2 is involved in nitric oxide signaling in the regulation of leaf senescence. The results showed that chlorophyll degradation in the double mutant leaves was significantly delayed. In addition, nosllnoal-mediated impairment in photochemical efficiency and integrity of thylakoid membranes was reverted by EIN2 mutations. The rapid upregulation of the known senescence marker genes in the nosl/noal mutant was severely inhibited in the double mutant during leaf senescence. Interestingly, the response of dark-grown nosl/noal mutant seedlings to ethylene was similar to that of wild type seedlings. Taken together, our findings suggest that EIN2 is involved in the regulation of early leaf senescence caused by NO deficiency, but NO deficiency caused by NOSIlNOA1 mutations does not affect ethylene signaling.

关键词： Arabidopsis dark EIN2 leaf senescence nitric oxide.

Preparation of Thermal-responsive Chitosan-graft-N-isopropyl- acrylamide Membranes via γ-Ray Irradiation

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Chinese Chemical Letters 2006年第9期17卷 1236-1238页

作者： qing mu Yue E FANG Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

A novel thermo-sensitive switching membrane has been prepared by radiation-induced simultaneous grafting N-isopropylacrylamide （NIPAAm） onto chitosan membrane. Fourier transform infrared spectroscopy （FTIR） was used to identify the structure of the grafted membranes. The surface morphology of the grafted membrane was observed from scanning electron microscopy （SEM）. Pure water flux measurements showed that water flux of the grafted membrane decreased with the increase of temperature, while that of chitosan membrane was constant. It was proved that grafted membrane was sensitive to temperature.

关键词： Chitosan membrane N-isopropylacrylamide γ-ray irradiation thermal-responsive.

Fault detection and optimization for networked control systems with uncertain time-varying delay

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Journal of Systems Engineering and Electronics 2015年第3期26卷 544-556页

作者： qing Wang Zhaolei Wang Chaoyang Dong Erzhuo niu School of Automation Science and Electrical Engineering Beihang University Beijing Aerospace Automatic Control Institute School of Aeronautic Science and Engineering Beihang University Flight Automatic Control Research Institute Aviation Industry Corporation

The observer-based robust fault detection filter design and optimization for networked control systems （NOSs） with uncer- tain time-varying delays are addressed. The NCSs with uncertain time-varying delays are modeled as parameter-uncertain systems by the matrix theory. Based on the model, an observer-based residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of the linear matrix inequality. Furthermore, a time domain opti- mization approach is proposed to improve the performance of the fault detection system. To prevent the false alarms, a new thresh- old function is established, and the solution of the optimization problem is given by using the singular value decomposition （SVD） of the matrix. A numerical example is provided to illustrate the effectiveness of the proposed approach.

关键词： fault detection networked control systems residual generator time-varying delay time domain optimization approach.

KFDA and clustering based multiclass SVM for intrusion detection

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 123-128页

作者： WEI Yu-xin WU mu-qing Institute of Communication Networks Intergrated Technique Beijing University of Posts and Telecommunications Beijing 100876 China

To improve the classification accuracy and reduce the training time, an intrusion detection technology is proposed, which combines feature extraction technology and multiclass support vector machine （SVM） classification algorithm. The intrusion detection model setup has two phases. The first phase is to project the original training data into kernel fisher discriminant analysis （KFDA） space. The second phase is to use fuzzy clustering technology to cluster the projected data and construct the decision tree, based on the clustering results. The overall detection model is set up based on the decision tree. Results of the experiment using knowledge discovery and data mining （KDD） from 99 datasets demonstrate that the proposed technology can be an an effective way for intrusion detection.

关键词： intrusion detection kernel fisher discriminant analysis fuzzy clustering support vector machine

Compound 3k治疗骨关节炎:调控氧化应激通路改善软骨细胞糖酵解的作用机制

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中国组织工程研究 2025年第2期29卷 363-370页

作者：郭素蓉曹士盛穆星彤杨青张娟天津医科大学口腔医学院天津市300041 天津医科大学口腔医院口腔修复科天津市300041

背景:骨关节炎现已被认为是一种代谢性疾病,既往研究表明糖酵解在骨关节炎的发生发展中起重要作用。Compound 3k作为一种新型糖酵解小分子抑制剂,具有抗炎及抗肿瘤等功效,因此可靶向糖酵解,有望为骨关节炎治疗提供新的思路。目的:基于... 详细信息

背景:骨关节炎现已被认为是一种代谢性疾病,既往研究表明糖酵解在骨关节炎的发生发展中起重要作用。Compound 3k作为一种新型糖酵解小分子抑制剂,具有抗炎及抗肿瘤等功效,因此可靶向糖酵解,有望为骨关节炎治疗提供新的思路。目的:基于缺氧诱导因子1α/活性氧的氧化应激通路探究Compound 3k在糖酵解过度活跃所导致的骨关节炎中的作用机制。方法:取对数生长期的ATDC5成软骨细胞,用10 ng/mL白细胞介素1β作用24 h诱导骨关节炎体外细胞模型,以CCK-8法检测不同浓度(0.25,0.5,1,2.5,5,10,15μmol/L)Compound 3k的细胞毒性,选出合适浓度进行后续实验。将软骨细胞随机分为对照组、模型组、治疗组,模型组以10 ng/mL的白细胞介素1β诱导,治疗组以Compound 3k预刺激2 h后与白细胞介素1β共培养,用CCK-8法检测各组细胞增殖情况;用ELISA试剂盒检测各组细胞炎症水平;用试剂盒检测各组细胞活性氧、细胞外乳酸脱氢酶及葡萄糖含量;qRT-PCR及Western blot检测相关炎症因子白细胞介素6、肿瘤坏死因子α及糖酵解相关基因葡萄糖转运蛋白1、甘油醛3-磷酸脱氢酶、单羧酸转运蛋白1和缺氧诱导因子1α的表达水平。结果与结论:①与对照组相比,模型组细胞增殖活性下降、糖酵解水平活跃,表现为细胞外乳酸脱氢酶含量增加(P<0.001),葡萄糖含量减少(P<0.001),相关炎症因子白细胞介素6(P<0.0001)及肿瘤坏死因子α(P<0.001),糖酵解相关基因葡萄糖转运蛋白1(P<0.001)、甘油醛3-磷酸脱氢酶(P<0.001)、单羧酸转运蛋白1(P<0.001)及缺氧诱导因子1α(P<0.001)的表达水平均上调,并伴随氧化应激,活性氧过量产生。②与模型组相比,Compound 3k的治疗有效提高细胞增殖活性,抑制过度活跃的糖酵解水平的同时,抑制了骨关节炎软骨细胞炎症(P<0.001)及糖酵解相关基因的表达(P<0.001),且抑制氧化应激,缺氧诱导因子1α的表达水平下调(P<0.0001),活性氧水平下降。③上述结果证实,Compound 3k抑制了白细胞介素1β诱导的软骨细胞炎症,其机制可能与糖酵解及缺氧诱导因子1α/活性氧介导的氧化应激有关。

关键词：骨关节炎糖酵解 Compound 3k 氧化应激 HIF-1α/ROS ATDC5细胞葡萄糖代谢白细胞介素1β 小分子药物