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Estimation of Hammerstein nonlinear systems with noises using filtering and recursive approaches for industrial control

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 260-271页

作者： Mingguang ZHANG Feng li Yang YU qingfeng CAO School of Electrical&Information Engineering Jiangsu University of TechnologyChangzhou213001China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225127China

This paper discusses a strategy for estimating Hammerstein nonlinear systems in the presence of measurement noises for industrial control by applying filtering and recursive approaches.The proposed Hammerstein nonlinear systems are made up of a neural fuzzy network(NFN)and a linear state`-space model.The estimation of parameters for Hammerstein systems can be achieved by employing hybrid signals,which consist of step signals and random signals.First,based on the characteristic that step signals do not excite static nonlinear systems,that is,the intermediate variable of the Hammerstein system is a step signal with different amplitudes from the input,the unknown intermediate variables can be replaced by inputs,solving the problem of unmeasurable intermediate variable information.In the presence of step signals,the parameters of the state-space model are estimated using the recursive extended least squares(RELS)algorithm.Moreover,to effectively deal with the interference of measurement noises,a data filtering technique is introduced,and the filtering-based RELS is formulated for estimating the NFN by employing random signals.Finally,according to the structure of the Hammerstein system,the control system is designed by eliminating the nonlinear block so that the generated system is approximately equivalent to a linear system,and it can then be easily controlled by applying a linear controller.The effectiveness and feasibility of the developed identification and control strategy are demonstrated using two industrial simulation cases.

关键词： Hammerstein nonlinear systems Neural fuzzy network Data filtering Hybrid signals Industrial control

Ultrasound-assisted isolation: A new method to isolate stromal vascular fraction

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Chinese Journal of Plastic and Reconstructive Surgery 2024年第1期6卷 8-15页

作者： Yiming Gao Xiaojie Zhang Poh-Ching Tan Yun Xie Peiqi Zhang Tianyu Zhang qingfeng li Shuangbai Zhou 1.Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine 2.Department of Burns and Plastic Surgery, Shanghai Changzheng Hospital 3.College of life Sciences, Shanghai Normal University Department of Plastic and Reconstructive Surgery Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Department of Burns and Plastic Surgery Shanghai Changzheng Hospital College of life Sciences Shanghai Normal University

Background: The stromal vascular fraction(SVF), a cluster of stem and progenitor cells isolated from adipose tissue, holds significant promise for application in regenerative medicine. However, the existing methods for SVF isolation are time-consuming and expensive. Thus, in this study, we explored a new method of SVF extraction—ultrasound-assisted SVF isolation(USASI)—and compared the viability and characteristics of SVF isolated using different methods.Methods: SVF extraction methods using different combinations of ultrasound power, ultrasound time, collagenase dosage, and collagenase digestion time were compared with those of the control group(collagenase digestion method). The cell yield and vitality of the SVF were evaluated via cell counting and trypan blue staining. The cell components and immunophenotypes of freshly isolated SVF were analyzed using flow cytometry. The proliferative capacity and differentiation potential of the SVF were also identified.Results: Ultrasonication at 95 W-20 k Hz for 30 s followed by digestion with 0.15% collagenase for 30 min was identified as the most suitable parameter for the USASI method in isolating SVF, as recommended based on the evaluation of various tested conditions. The USASI method significantly reduced the collagenase dosage and shortened the digestion time. Compared to the collagenase digestion method, the USASI method had a higher cell yield and cell viability, with no adverse effects on cell components, proliferative capacity, or multipotential differentiation capacity.Conclusion: With reduced processing time, lower collagenase dosage, and increased cell yield without impairing the viability and characteristics of SVF, USASI holds the potential to emerge as a time-saving and cost-effective method for future clinical applications.

关键词： Stromal vascular fractions SVF isolation Mechanical force Ultrasound

How the microenvironment dominated by the distance effect to regulate the FeN_(4)site ORR activity and selectivity?

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Nano Research 2024年第6期17卷 5735-5741页

作者： Peng li qingfeng Guo Jianrui Zhang Ruilin Chen Shujiang Ding Yaqiong Su School of Chemistry Engineering Research Center of Energy Storage Materials and Devices of Ministry of EducationNational Innovation Platform(Center)for Industry-Education Integration of Energy Storage TechnologyXi’an Jiaotong UniversityXi’an 710049China Huanghe Science and Technology College Zhengzhou 450063China General Research Institute of Engineering of Gotion High-Tech Hefei 230041China

The distance effect of the doped heteroatoms away from the catalytic centers has rarely been reported.In this work,we conducted density functional theory calculations to thoroughly investigate the influence of heteroatom(N,P,B,and S atoms)doping distance on the oxygen reduction reaction(ORR)activity of graphene-based FeN_(4)sites.We uncovered a Sabatier-like relationship between heteroatom doping distance and ORR activity of FeN_(4)sites.The nearest doping does not significantly improve and even block the ORR activity of FeN_(4)sites.Optimal ORR activity is achieved when the heteroatoms are 4-5Å(N,P,and S atoms)or 6-7Å(B atoms)away from the Fe atoms.Analysis of electronic structure indicates that distance effect can modulate the local chemical environment of Fe atoms,thereby account for the changes in ORR activity along with the doping distance and doping atoms.This study provides insights into the influence of heteroatom doping on the chemical environment of reaction active centers,and provides the theoretical guidance for controlling the doping distance of heteroatoms to achieve optimal catalytic activity and selectivity.

关键词： distance effect microenvironment heteroatom doping FeN_(4) Sabatier-like relationship structure-activity relationship

Multiple thermal events recorded in the Acasta Gneiss Complex:Evidence from in-situ dating of zircon, titanite, and apatite

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Science China Earth Sciences 2024年第3期67卷 673-686页

作者： qingfeng MEI Jinhui YANG Jinfeng SUN Qiuli li Shitou WU Xiaoxiao liNG Peng PENG Hao WANG State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China

In-situ dating of the zircons, titanites, and apatites in the rock fragments of approximately 1 cm2in size from the Acasta Gneiss Complex was performed using secondary ion mass spectrometry or laser ablation inductively coupled plasma mass spectrometry to provide constraints on the thermal history of the Acasta Gneiss Complex. The zircons in these rock fragments typically exhibit multiple age populations, reflecting the presence of inherited zircons or the post-crystallization process of zircon overgrowth. Combined with previous studies, our zircon dating results reveal multiple magmatic events that occurred in the Acasta Gneiss Complex, specifically at >3.96, ~3.72, and ~3.57 Ga, respectively. A titanite Pb-Pb isochron age of2911±22 Ma(95% confidence level, MSWD=1.5) for sample AY199 is identified, consistent with the timing of the latest Archean magmatism in the Acasta Gneiss Complex. The titanite U-Pb ages for samples AC478 and AY066 are 1932±270 Ma(95% confidence level, MSWD=2.3) and 1813±45 Ma(95% confidence level, MSWD=2.3), respectively. The apatites in sample P090803-C exhibit a Pb-Pb isochron age of 1833±26 Ma(95% confidence level, MSWD=1.4). The apatite U-Pb ages for samples AC478, AY199, and AY066 are 1850±20 Ma(95% confidence level, MSWD=1.3), 1827±100 Ma(95% confidence level, MSWD=6.3), and 1807±58 Ma(95% confidence level, MSWD=3.9), respectively. Titanites in samples AC478 and AY066, as well as the apatites in all four investigated samples, show a uniform age(Pb-Pb or U-Pb age) of ~1.9–1.8 Ga,indicating U-Pb system reset in these minerals due to the Wopmay orogeny and documenting that the peak temperature condition associated with the Wopmay orogeny exceeded the apatite U-Pb closure temperature and approached or exceeded that of titanite.

关键词： Zircon Titanite Apatite Acasta Gneiss Complex Wopmay Orogen

Decellularized extracellular matrix mediates tissue construction and regeneration

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Frontiers of Medicine 2022年第1期16卷 56-82页

作者： Chuanqi liu Ming Pei qingfeng li Yuanyuan Zhang Department of Plastic and Burn Surgery West China HospitalSichuan UniversityChengdu 610041China Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Stem Cell and Tissue Engineering Laboratory Department of OrthopaedicsWest Virginia UniversityMorgantownWV 26506USA Wake Forest Institute for Regenerative Medicine Wake Forest University Health SciencesWinston-SalemNC 27109USA

Contributing to organ formation and tissue regeneration,extracellular matrix(ECM)constituents provide tissue with three-dimensional(3D)structural integrity and cellular-function regulation.Containing the crucial traits of the cellular microenvironment,ECM substitutes mediate cell–matrix interactions to prompt stem-cell proliferation and differentiation for 3D organoid construction in vitro or tissue regeneration in vivo.However,these ECMs are often applied generically and have yet to be extensively developed for specific cell types in 3D cultures.Cultured cells also produce rich ECM,particularly stromal cells.Cellular ECM improves 3D culture development in vitro and tissue remodeling during wound healing after implantation into the host as well.Gaining better insight into ECM derived from either tissue or cells that regulate 3D tissue reconstruction or organ regeneration helps us to select,produce,and implant the most suitable ECM and thus promote 3D organoid culture and tissue remodeling for in vivo regeneration.Overall,the decellularization methodologies and tissue/cell-derived ECM as scaffolds or cellular-growth supplements used in cell propagation and differentiation for 3D tissue culture in vitro are discussed.Moreover,current preclinical applications by which ECM components modulate the wound-healing process are reviewed.

关键词： decellularized extracellular matrix 3D culture organoids tissue repair

Machine learning transforms the inference of the nuclear equation of state

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Frontiers of physics 2023年第6期18卷 33-37页

作者： Yongjia Wang qingfeng li School of Science Huzhou UniversityHuzhou 313000China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Our knowledge of the properties of dense nuclear matter is usually obtained indirectly via nuclear experiments,astrophysical observations,and nuclear theory calculations.Advancing our understanding of the nuclear equation of state(EOS,which is one of the most important properties and of central interest in nuclear physics)has relied on various data produced from experiments and calculations.We review how machine learning is revolutionizing the way we extract EOS from these data,and summarize the challenges and opportunities that come with the use of machine learning.

关键词： nuclear equation of state machine learning nuclear theory nuclear experiment

Breeding exceptionally fragrant soybeans for soy milk with strong aroma

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Journal of Integrative Plant Biology 2024年第4期66卷 642-644页

作者： Hongtao Xie Minglei Song Xuesong Cao qingfeng Niu Jianhua Zhu Shasha li Xin Wang Xiaomu Niu Jian-Kang Zhu Bellagen Biotechnology Co.Ltd. Jinan 250000China Institute of Advanced Biotechnology and School of life Sciences Southern University of Science and TechnologyShenzhen 518055China School of life Sciences Anhui Agricultural UniversityHefei 230036China Shandong Normal University Jinan 250000China

Soybean(Glycine max(L.)Merr.)is a major source of vegetable protein and oil in human diet and animal nutrition.Soybean seeds have been extensively used in various food products and snacks.Taste quality,particularly the aroma,affects cooking and eating,and ultimately influences consumer preference.Soy milk is particularly popular in China and has been gaining popularity in many other countries in the world.

关键词： exceptional soybean cooking

The key role of myostatin b in somatic growth in fishes derived from distant hybridization

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Science China(life Sciences) 2024年第7期67卷 1441-1454页

作者： qingfeng liu Lujiao Duan Bei li Xuanyi Zhang Fanglei liu Jianming Yu Yuqin Shu Fangzhou Hu Jingjing lin Xiaoxia Xiong Shaojun liu State Key Laboratory of Developmental Biology of Freshwater Fish Hunan Normal UniversityChangsha 410081China College of life Sciences Hunan Normal UniversityChangsha 410081China

The basic mechanism of heterosis has not been systematically and completely characterized.In previous studies,we obtained three economically important fishes that exhibit rapid growth,WR(WCC♀×RCC♂),WR-Ⅱ(WR♀×WCC♂),and WR-Ⅲ(WR-Ⅱ♀×4nAU♂),through distant hybridization.However,the mechanism underlying this rapid growth remains unclear.In this study,we found that WR,WR-Ⅱ,and WR-Ⅲshowed muscle hypertrophy and higher muscle protein and fat contents compared with their parent species(RCC and WCC).Candidate genes responsible for this rapid growth were then obtained through an analysis of 12 muscle transcriptomes.Notably,the mRNA level of mstnb(myostatin b),which is a negative regulator of myogenesis,was significantly reduced in WR,WR-Ⅱ,and WR-Ⅲcompared with the parent species.To verify the function of mstnb,a mstnb-deficient mutant RCC line was generated using the CRISPR-Cas9 technique.The average body weight of mstnb-deficient RCC at 12 months of age was significantly increased by 29.57%compared with that in wild-type siblings.Moreover,the area and number of muscle fibers were significantly increased in mstnb-deficient RCC,indicating hypertrophy and hyperplasia.Furthermore,the muscle protein and fat contents were significantly increased in mstnb-deficient RCC.The molecular regulatory mechanism of mstnb was then revealed by transcription profiling,which showed that genes related to myogenesis(myod,myog,and myf5),protein synthesis(PI3K-AKT-mTOR),and lipogenesis(pparγand fabp3)were highly activated in hybrid fishes and mstnb-deficient RCC.This study revealed that low expression or deficiency of mstnb regulates somatic growth by promoting myogenesis,protein synthesis,and lipogenesis in hybrid fishes and mstnb-deficient RCC,which provides evidence for the molecular mechanism of heterosis via distant hybridization.

关键词： distant hybridization heterosis somatic growth myostatin b genome editing

Study on the growth of platinum nanowires as cathode catalysts in proton exchange membrane fuel cells

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 364-375页

作者： Ruiqing Wang Xiaolan Cao Sheng Sui Bing li qingfeng li Institute of Fuel Cells Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai200237China Department of Energy Conversion and Storage Technical University of Denmark2800LyngbyCopenhagenDenmark

The platinum nanowires have been verified to be a promising catalyst to promote the performance of proton exchange membrane fuel cells.In this paper,accurately controlled growth of nanowires in a carbon matrix is achieved for reducing Pt loading.The effects of formic acid concentration and reaction temperature on the morphology and size of the Pt nanowires,as well as their electrochemical performances in a single cell,are investigated.The results showed that the increase in the formic acid concentration results in a volcano trend with the length of Pt nanowires.With increasing reduction temperature,the diameter of Pt nanowires increases while Pt particles evolve from one-dimensional to zero-dimensional up to 40°C.A mechanism of the Pt nanowires growth is proposed.The optimized Pt nanowires electrode exhibits a power density(based on electrochemical active surface area)79%higher than conventional Pt/C one.The control strategy obtained contributes to the design and control of novel nanostructures in nano-synthesis and catalyst applications.

关键词： Pt nanowires morphology structure control in situ growth mechanism proton exchange membrane fuel cells