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An extended state observer with adjustable bandwidth for measurement noise

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Journal of Systems Engineering and Electronics 2024年第1期35卷 233-241页

作者： ZHANG Shihua QI Xiaohui YANG Sen Shijiazhuang Campus Army Engineering University of PLAShijiazhuang 050053China

In this paper,a bandwidth-adjustable extended state observer(ABESO)is proposed for the systems with measurement noise.It is known that increasing the bandwidth of the observer improves the tracking speed but tolerates noise,which conflicts with observation accuracy.Therefore,we introduce a bandwidth scaling factor such that ABESO is formulated to a 2-degree-of-freedom system.The observer gain is determined and the bandwidth scaling factor adjusts the bandwidth according to the tracking error.When the tracking error decreases,the bandwidth decreases to suppress the noise,otherwise the bandwidth does not change.It is proven that the error dynamics are bounded and converge in finite time.The relationship between the upper bound of the estimation error and the scaling factor is given.When the scaling factor is less than 1,the ABESO has higher estimation accuracy than the linear extended state observer(LESO).Simulations of an uncertain nonlinear system with compound disturbances show that the proposed ABESO can successfully estimate the total disturbance in noisy environments.The mean error of total disturbance of ABESO is 15.28% lower than that of LESO.

关键词： extended state observer(ESO) boundedness and convergence adjustable bandwidth measurement noise

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齐晓慧医生对血小板减少性紫癜的认识

中国蒙医药（蒙） 2023年第12期18卷 127-129页

作者：杨蒙齐晓慧不详

A Bird’s Eye View of Quantitative Proteome of Tumor Tissues from Lung Cancer Patients by a High Precision Mass Spectrometry Method

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Chemical Research in Chinese Universities 2024年第1期40卷 136-144页

作者： DU xiaohui LI Encheng WANG qi YOU Xin Lung Cancer Transitional Medicine Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China Department of Scientific Research Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China Department of Respiratory Medicine The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China

Lung cancer produces a high incidence of malignant tumors.There have been many studies on lung cancer using mass spectrometry(MS)technologies.However,most studies have focused on humoral samples.In this work,26 pairs of tissue samples(tumor vs.para-tumor)from patients with lung cancer were analyzed using liquid chromatography-tandem MS(LC-MS/MS)with data-independent acquisition mode.In total,3152 proteins were quantified from tissue samples with high confidence,including 189 up-regulated and 522 down-regulated proteins(tumor vs.para-tumor).In addition,79 and 690 proteins were identified only in para-cancerous samples and cancerous samples,respectively.The results from bio-informatics tools indicated that altered proteins like PEBP1,HRG and LYZ could be ideal reservoirs for screening the potential biomarkers for lung cancer.It is believed these tissue-specific proteomics results will assist in the studies of lung cancer.

关键词： Lung cancer Proteome Data-independent aquisition

Direction navigability analysis of geomagnetic field based on Gabor filter

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Journal of Systems Engineering and Electronics 2018年第2期29卷 378-385页

作者： XIAO Jing DUAN Xiusheng QI Xiaohui WANG Jianchen Army Engineering University Shijiazhuang 050003China Government Representative Office Northwestern Polytechnical UniversityXi’an 710065China

Direction navigability analysis is a supplement to the navigability analysis theory, in which extraction of the direction suitable-matching features(DSMFs) determines the evaluation performance. A method based on the Gabor filter is proposed to estimate the direction navigability of the geomagnetic field. First,the DSMFs are extracted based on the Gabor filter’s responses.Second, in the view of pattern recognition, the classification accuracy in fault diagnosis is introduced as the objective function of the hybrid particle swarm optimization(HPSO) algorithm to optimize the Gabor filter’s parameters. With its guidance, the DSMFs are extracted. Finally, a direction navigability analysis model is established with the support vector machine(SVM), and the performances of the models under different objective functions are discussed. Simulation results show the parameters of the Gabor filter have a significant influence on the DSMFs, which, in turn, affects the analysis results of direction navigability. Moreover, the risk of misclassification can be effectively reduced by using the analysis model with optimal Gabor filter parameters. The proposed method is not restricted in geomagnetic navigation, and it also can be used in other fields such as terrain matching and gravity navigation.

关键词： geomagnetic navigation navigability analysis direction navigability Gabor filter direction suitable-matching feature

Random field characterization of uniaxial compressive strength and elastic modulus for intact rocks

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Geoscience Frontiers 2018年第6期9卷 1609-1618页

作者： Huaxin Liu xiaohui qi School of Civil and Environmental Engineering Nanyang Technological University

Rock properties exhibit spatial variabilities due to complex geological processes such as sedimentation,metamorphism, weathering, and tectogenesis. Although recognized as an important factor controlling the safety of geotechnical structures in rock engineering, the spatial variability of rock properties is rarely quantified. Hence, this study characterizes the autocorrelation structures and scales of fluctuation of two important parameters of intact rocks, i.e. uniaxial compressive strength(UCS) and elastic modulus(EM).UCS and EM data for sedimentary and igneous rocks are collected. The autocorrelation structures are selected using a Bayesian model class selection approach and the scales of fluctuation for these two parameters are estimated using a Bayesian updating method. The results show that the autocorrelation structures for UCS and EM could be best described by a single exponential autocorrelation function. The scales of fluctuation for UCS and EM respectively range from 0.3 m to 8.0 m and from 0.3 m to 8.4 m.These results serve as guidelines for selecting proper autocorrelation functions and autocorrelation distances for rock properties in reliability analyses and could also be used as prior information for quantifying the spatial variability of rock properties in a Bayesian framework.

关键词： Uniaxial compressive strength Elastic modulus Scale of fluctuation Autocorrelation function Spatial variability Bayesian approach

Multifunctional binder designs for lithium-sulfur batteries

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Journal of Energy Chemistry 2019年第12期28卷 88-100页

作者： qi qi xiaohui Lv Wei Lv Quan-Hong Yang Shenzhen Geim Graphene Center Engineering Laboratory for Functionalized Carbon Materials.Graduate School at ShenzhenTsinghua UniversityShenzhen 518055GuangdongChina Nanoyang Group.State Key Laboratory of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Lithium-sulfur(Li-S)batteries are promising next-generation high energy density batteries but their practical application is hindered by several key problems,such as the intermediate polysulfide shuttling and the electrode degradation caused by the sulfur volume changes.Binder acts as one of the most essential components to build the electrodes of Li-S batteries,playing vital roles in improving the performance and maintaining the integrity of the cathode structure during cycling,especially those with high sulfur loadings.To date,tremendous efforts have been devoted to improving the properties of binders,in terms of the viscosity,elasticity,stability,toughness and conductivity,by optimizing the composition and structure of polymer binders.Moreover,the binder modification endows them strong polysulfide trapping ability to suppress the shuttling and decreases the swelling to maintain the porous structure of cathode.In this review,we summarize the recent progress on the binders for Li-S batteries and discuss the various routes,including the binder combination use,functionalization,in-situ polymerization and ion cross-linking,etc.,to enhance their performance in stabilizing the cathode,building the high sulfur loading electrode and improving the cyclic stability.At last,the design principles and the problems in further applications are also highlighted.

关键词： Polymer binders Natural polymers Artificial polymers Combination Modification

Effect of economic policies on the stock and bond market under the impact of COVID-19

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Journal of Safety Science and Resilience 2022年第1期3卷 24-38页

作者： Feng Liu Deli Kong Zilong Xiao xiaohui Zhang Aimin Zhou Jiayin qi School of Computer Science and Technology East China Normal UniversityShanghai 200062China Institute of Artificial Intelligence and Change Management Shanghai University of International Business and EconomicsShanghai 203356China School of Business and Management Shanghai International Studies UniversityShanghai 201620China School of Data and Computer Science Sun Yat-Sen UniversityGuangzhou 528406China qianhai Financial Holdings Guangzhou 510030China

The global epidemic of COVID-19 has made a huge impact on global health and financial markets.And the spread of the virus has stalled economic development in many parts of the world.As stocks and bonds are two important financial assets,how to take appropriate economic policies to restore the stock and bond markets is the focus of governments as they are seeking for quick recovery.Based on the Event Study method and the GARCH model,data from 1 October 2019 to 1 April 2020 were collected from 26 countries or regions as analytic samples.The results show:1)COVID-19 has made greater impacts on the stock market than the bond market;2)the economic policy responses after the COVID-19 has brought impacts on both of the stock and the bond markets;3)the monetary policy responses has brought greater volatility to the stock market than the fiscal policy responses,while the fiscal policy responses has brought greater volatility to the bond market than the monetary policy;4)the fiscal policy has brought more positive effects on the stock market,and monetary policy has brought more positive effects on the bond market.This research is helpful to understand the mechanism of COVID-19’s impacts on the stock and bond market.And it is of great practical significance to the governments’decisions to make economic policy responses after an epidemic.

关键词： COVID-19 epidemic Event study method Global stock and bond market Return and volatility

Assembly and Post-modification of Fe3O4@MIL-100（Fe） for Knoevenagel Condensation

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Chemical Research in Chinese Universities 2018年第4期34卷 655-660页

作者： ZHANG Yanmei ZHANG Fan ZHANG Xiang XU Yingmei QI Xiaohui QUAN Chunshan Key Laboratory of Biotechnology and Bioresources Utilization Ministry of Education College of Life Science Dalian Minzu University Dalian 116600 P. R. China

Many efforts have been devoted to the integration of magnetic nanoparticles and metal organic frame- works, which makes it easy and simple to separate the nano-sized metal organic frameworks from liquid phase. Amino-functionalized magnetic metal organic frameworks[Fe3O4@MIL-100（Fe）-NH2] were prepared by a stepwise assembly method followed by post-modification with electron-rich reagent. This magnetic catalyst was characterized by means of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron micrnscopy（SEM） and nitrogen adsorption, and tested in Knoevenagel condensation as a base catalyst. The magnetic catalyst exhibits a core-shell structure and can afford a high activity for the Knoevenagel condensation due to its bifunctional property and reduced diffusion limitation. Furthermore, it could be recovered magnetically and recycled three times. Although activity loss was observed in the recycle experiments, it could be reactivated by dispersing in a fresh modifier solution.

关键词： Fe3O4 MIL-100（Fe） Heterogeneous catalyst Knoevenagel condensation Magnetic separation

Evaluation and selection of yeasts as potential aroma enhancers for the production of dry-cured ham

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Food Science and Human Wellness 2023年第1期12卷 324-335页

作者： xiaohui Gong Ruifang Mi Xi Chen qiujin Zhu Suyue Xiong Biao qi Shouwei Wang School of Liquor&Food Engineering Guizhou University/Guizhou Provincial Key Laboratory of Agricultural and Animal Products Storage and ProcessingGuiyang 550025China China Meat Research Center Beijing 100068China

Yeasts play a critical role in the flavor formation of dry-cured ham.In this study,41 yeast isolates from the dry-cured ham at different processing stages were evaluated for their technological properties.Debaryomyces hansenii was the most dominant yeast and has been detected at each phase of dry-cured ham,followed by Candida zeylanoides which was mainly detected in salting phase.Yarrowia bubula and Yarrowia alimentaria were found at the first two-phase of dry-cured ham.All isolates of yeast showed enzymatic activities against milk protein and tributyrin,while only 4 strains displayed proteolytic activity on meat protein.Yeast strains were grown in a meat model medium and volatile compounds were identified.The result showed that inoculated yeast strains could promote the production of volatiles and there were significant differences among strains.D.hansenii S25 showed the highest production of volatile compounds,followed by the strain C.zeylanoides C4.D.hansenii S25 was the highest producer of alcohols showing the highest production of benzeneethanol and 3-(methylthio)-1-propanol.Based on OAV and PLS analysis,D.hansenii S25 was strongly correlated with overall flavor and key volatile compounds of dry-cured ham,which could be selected as potential starter cultures.

关键词： Yeast Flavor Dry-cured ham Meat model medium Debaryomyces hansenii