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Active and passive compliant force control of ultrasonic surface rolling process on a curved surface

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Chinese Journal of Aeronautics 2022年第7期35卷 289-299页

作者： Kaiming ZHANG Ji WANG Yixin liu Shuang Liu Xiancheng ZHANG School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

Ultrasonic surface rolling process(USRP)is one of the effective mechanical surface enhancement techniques.During the USRP,unstable static force will easily do harm to the surface quality.In order to achieve a higher surface quality on the part with a curved surface,an active and passive compliant USRP system has been developed.The compliant USRP tool can produce the natural obedience deformation along the part surface.Force control based on the fuzzy Proportional-integral-derivative(PID)method is then designed to maintain the static force during the USRP.Experiments have been performed on a real aero-engine blade with curved surface.It is proved that the deigned active and passive compliant USRP system can significantly reduce the force variation from 42.2 N to 4.2 N,and achieve a uniform surface quality after processing.

关键词： Active and passive compliant Curved surface Force control Surface integrity Ultrasonic surface rolling process

Hydro-climatic Characteristics of Yarlung Zangbo River Basin since the Last Glacial Maximum

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Advances in Atmospheric Sciences 2022年第3期39卷 415-426页

作者： Shuang Liu Kaiheng HU Weiming liu Paul A.CARLING Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Geography&Environment University of SouthamptonHighfieldSouthamptonSO171BJUK

Global climate changes significantly impact the water condition of big rivers in glacierized high mountains. However,there is a lack of studies on hydrological changes within river basins caused by climate changes over a geological timescale due to the impossibility of direct observations. In this study, we examine the hydro-climatic variation of the Yarlung Zangbo River Basin in the Tibet Plateau since the Last Glacial Maximum(LGM) by combining δ18 O proxy records in Indian and Omani caves with the simulated Indian summer monsoon, surface temperature, precipitation, evapotranspiration and runoff via the Community Climate System Model and the reconstructed glacier coverage via the Parallel Ice Sheet Model. The mean river runoff was kept at a low level of 145 billion cubic meters per year until an abrupt increase at a rate of 8.7 million cubic meters per year in the B?lling-Aller?d interval(BA). The annual runoff reached a maximum of 250 billion cubic meters in the early Holocene and then reduced to the current value of 180 billion cubic meters at a rate of 6.4 million cubic meters per year. The low runoff in the LGM and Heinrich Stadial 1(HS1) is likely attributed to such a small contribution of precipitation to runoff and the large glacier cover. The percentage of precipitation to runoff was only 20%during the LGM and HS1. Comparison of glacier area among different periods indicates that the fastest deglaciation occurred during the late HS1, when nearly 60% of glacier area disappeared in the middle reach, 50% in the upper reach,and 30% in the lower reach. The rapid deglaciation and increasing runoff between the late HS1 and BA may have accelerated widespread ice-dam breaches and led to extreme outburst flood events. Combining local geological proxy records and regional simulations could be a useful approach for the study of paleo-hydrologic variations in big river basins.

关键词： Yarlung Zangbo River Basin Indian summer monsoon glacier change runoff variability since the LGM

Anti-saturation fault-tolerant adaptive torsional vibration control with fixed-time prescribed performance for rolling mill main drive system

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Journal of Iron and Steel Research(International) 2024年第3期31卷 660-669页

作者： Shuang Liu Chen Du Cong Zhang Zhen-hua Bai Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter perturbations.First,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the system.Then,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter perturbations.Based on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation method.According to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric constraint.Finally,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

关键词： Fixed-time prescribed performance Control input saturation Actuator fault Unknown time-varying gain Adaptive control Asymmetric constraint

Effects of input method and display mode of situation map on early warning aircraft reconnaissance task performance with different information complexities

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Chinese Journal of Aeronautics 2023年第1期36卷 105-114页

作者： Chaoran LIANG Shuang Liu Xiaoru WANYAN Chengping liu Xu XIAO Yuchen MIN School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China China Academy of Electronics and Information Technology Beijing 100041China

Early Warning Aircraft(EWA)are the main force for air detection and its Human-Machine Interface(HMI)should be designed to support task efficiency and safety.With the appli-cation of advanced input method and interface design in EWA,little is known about their actual usability in terms of human factors and ergonomics.The aim of this study was to investigate the effects of the input method and display mode of the situation map on EWA reconnaissance task performance with different information complexities.Eighteen participants attended a three-factor within-subject design experiment with input method(touch screen and mouse),display mode of the situation map(color and grayscale),and information complexity(high and low)as the inde-pendent variables.Participant behavior performance,subjective workload,heart rate/heart rate variability,and eye movements were recorded as the dependent variables.The results suggest that a touch screen requires greater task completion time and has greater physical demands than mouse operation;however,it also facilitates information processing by reducing the average fixation time.Color mode significantly decreases saccade counts compared to grayscale mode and is considered more appropriate for target search tasks as it induces less visual search load.High information complexity produces significant negative effects on behavior performance and subjective workload.It also has significant interaction effects with input method on fixation and saccade counts.The findings have implications in the optimization design of Human–Machine Interface for EWA task systems.

关键词： Early warning aircraft Eye tracking Heart rate/heart rate varia-tions Human–Machine Interface(HMI) Touch screens

Identification of different degrees of processed ginger using GC-IMS combined with machine learning

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Journal of Pharmaceutical Analysis 2024年第1期14卷 149-151页

作者： Shuang Liu Hongjing Dong Minmin Zhang Wei Geng Xiao Wang Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Shandong Analysis and Test CenterQilu University of Technology(Shandong Academy of Sciences)Jinan250014China Key Laboratory for Natural Active Pharmaceutical Constituents Research in Universities of Shandong Province School of Pharmaceutical SciencesQilu University of Technology(Shandong Academy of Sciences)Jinan250014China Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao University Jinan250014China

Ginger,the rhizomes of Zingiber officinale Roscoe,was a wellknown edible plant species commonly used in China,which has pungent flavor[1].Ginger has numerous chemical compounds,such as phenolic constituents,volatile compounds(VOCs),and polysaccharides[2].Among them,VOCs are considered one of the effective compounds in ginger due to their functional properties,including anti-inflammatory,antioxidant,and analgesic[3].

关键词： phenolic edible rhizome

Online Scheduling on Two Parallel Identical Machines Under a Grade of Service Provision

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Journal of the Operations Research Society of China 2022年第4期10卷 689-702页

作者： shuang Cai Ke liu Data Department Beijing Kingsoft Cloud Network Technology Co.Ltd.Beijing100086China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100190China

In this paper,we investigate online scheduling problems on two parallel identical machines under a grade of service provision with makespan as the objective function.The jobs arrive over time and each job can be scheduled only when it has already been arrived.We consider three different versions:(i)the two machines cannot be idle at the same time until all arrived jobs have been processed;(ii)further to the first problem,jobs are processed on a first-come,first-serviced basis;(iii)each job must be assigned to one of the two machines as soon as it arrives.Respectively for three online scheduling problems,optimal online algorithms are proposed with competitive ratio(√5+1)/2,(√5+1)/2 and 5/3.

关键词： Online scheduling Parallel machines A grade of service provision GoS

Regulating tumor suppressor genes:post-translational modifications

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1688-1712页

作者： Ling Chen Shuang Liu Yongguang Tao Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of EducationDepartment of PathologyXiangya HospitalSchool of Basic MedicineCentral South University410078 ChangshaHunanChina NHC Key Laboratory of Carcinogenesis(Central South University) Cancer Research InstituteCentral South University410078 ChangshaHunanChina Department of Oncology Institute of Medical SciencesNational Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South University410008 ChangshaHunanChina Hunan Key Laboratory of Early Diagnosis and Precision Therapy Department of Thoracic SurgerySecond Xiangya HospitalCentral South University410011 ChangshaChina

Tumor suppressor genes cooperate with each other in tumors.Three important tumor suppressor proteins,retinoblastoma(Rb),p53,phosphatase,and tensin homolog deleted on chromosome ten(PTEN)are functionally associated and they regulated by posttranslational modification(PTMs)as well.PTMs include phosphorylation,SUMOylation,acetylation,and other novel modifications becoming growing appreciated.Because most of PTMs are reversible,normal cells use them as a switch to control the state of cells being the resting or proliferating,and PTMs also involve in cell survival and cell cycle,which may lead to abnormal proliferation and tumorigenesis.Although a lot of studies focus on the importance of each kind of PTM,further discoveries shows that tumor suppressor genes(TSGs)form a complex“network”by the interaction of modification.Recently,there are several promising strategies for TSGs for they change more frequently than carcinogenic genes in cancers.We here review the necessity,characteristics,and mechanisms of each kind of post-translational modification on Rb,p53,PTEN,and its influence on the precise and selective function.We also discuss the current antitumoral therapies of Rb,p53 and PTEN as predictive,prognostic,and therapeutic target in cancer.

关键词： suppressor translational precise

Wide-ranging Force Responsive Composites based on 1,2-Dioxetane and ZnS as Luminescent Probes in Polyurethanes

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Chinese Journal of Polymer Science 2023年第8期41卷 1162-1168,I0005页

作者： Jin-Hui Zhang Shuang Liu Yuan Yuan Yu-Lan Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300354Chin State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012Chin

Combining the advantages of mechanochemiluminescence from 1,2-dioxetane and elastico-mechanoluminescence from ZnS particles,a new kind of mechanoluminescent polymer composites are developed.They can emit bright luminescence with two distinct colors at different strains,empowering a verstaile mechanochemical strategy for force sensing and damage detection at a wider force responsive range.

关键词： Mechanochemiluminescence 1,2-Dioxetane Elastico-mechanoluminescence ZnS Polymer composites

Slow magnetic relaxation in a 3D dysprosium(Ⅲ)-fluoro-oxalate framework containing zig-zag [Dy-F]n chains

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Journal of Rare Earths 2023年第1期41卷 100-107页

作者： Leilei Li Yifan Fang Shuang Liu Mingfei Hu Wenzhen Wang College of Chemistry and Chemical Engineering Xi'an Shiyou UniversityXi'an 710065China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Dysprosium complexes based on [F-Dy] or near-linear [F-Dy-F] unit are of great concern in the field of single-molecule magnets due to their large magnetic anisotropy.Here,the crystal structure and the magnetic relaxation dynamics were reported for a three-dimensional(3 D) metal-organic framework(MOF):[DyF(C_(2)O_(4))(H_(2)O)2]n·2nH_(2)O(1),which is the unique MOF containing zig-zag [Dy-F]_(n) chains.Magnetic susceptibility characterization reveals that 1 is one of the few 3 D MOFs which show slow magnetic relaxation under zero dc field.And the effective energy barrier of 72 K for 1 is also higher than most Dy-based 3 D MOFs.The diamagnetic ion dilution study shows that the ferromagnetic exchange couplings mainly transmitted by F^(-) bridges in 1 contribute little to the energy barrier,but effectively suppress the quantum tunneling process and result in a smooth hysteresis loop with no waist-restricted step.

关键词： Dysprosium complex Fluoride Magnetic property Slow magnetic relaxation Exchange coupling Rare earths