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Global adaptive output-feedback tracking with prescribed performance for uncertain nonlinear systems

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Science China(Information Sciences) 2024年第5期67卷 150-164页

作者： yuan WANG Yungang liu School of Control Science and Engineering Shandong University

At present, one typical control strategy for guaranteeing transient and steady-state performance is funnel control and prescribed performance control. The strategy features completely discarding the system nonlinearities, even if they are completely known and available. Such an intrinsic feature requires the controller to produce a larger control effect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we fully take advantage of known information on nonlinearities in control design, instead of completely discarding it as done in funnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of output feedback, tracking control, and the performance *** such, an adaptive output-feedback scheme is developed for global tracking with spatiotemporal performance specifications: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output feedback prescribed performance unknown control direction dynamic high gain global tracking

Cu-substituted nickel hexacyanoferrate with tunable reaction potentials for superior ammonium ion storage

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Journal of Materials Science & Technology 2024年第2期169卷 19-27页

作者： Leiyu Fan Guangchang shu Yiwen liu Haoxiang Yu Lei Yan Liyuan Zhang Jie shu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

In this work,a variety of Cu_(x)Ni_(2-x)Fe(CN)_(6)(x=0,0.4,0.8,1.2,1.6,2)cathodes for ammonium ion batteries are prepared and their electrochemical performances are *** the introduction of copper in nickel hexacyanoferrate,the electrochemical performance varies without changing the structure of nickel *** increase of Cu content in nickel hexacyanoferrate leads to the enhancement of reaction potential and *** results suggest that the substitution of Cu for Ni has a positive effect on improving the cycling stability and rate capacity of nickel hexacyanoferrate when x in Cu_(x)Ni_(2-x)Fe(CN)_(6)is less than ***,Cu_(0.4)Ni_(1.6)Fe(CN)_(6)exhibits the best cycling per-formance(capacity retention of 97.54%at 0.3 C)and the highest rate capacity(41.4 mAh g^(-1)at 10 C)in Cu_(x)Ni_(2-x)Fe(CN)_(6).Additionally,the X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)tests also reveal that the structural evolution of Cu_(0.4)Ni_(1.6)Fe(CN)_(6)is highly reversible upon NH_(4)^(+)***,this work proposes a candidate material for ammoniumion batteries and offers a novel avenue for adjusting the operating potential of the material.

关键词： Nickel hexacyanoferrate Copper hexacyanoferrate NH_(4)^(+)storage Ammonium ion batteries Aqueous batteries

Remote sensing image encryption algorithm utilizing 2D Logistic memristive hyperchaotic map and SHA-512

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Science China(Technological Sciences) 2024年第5期67卷 1553-1566页

作者： LAI Qiang liu yuan YANG Liang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang330013China

The two-dimensional Logistic memristive hyperchaotic map(2D-LMHM)and the secure hash SHA-512 are the foundations of the unique remote sensing image encryption algorithm(RS-IEA)suggested in this *** proposed map is formed from the improved Logistic map and the memristor,which has wide phase space and hyperchaotic range and is exceptionally excellent to be utilized in specific *** proposed image algorithm uses the permutation-assignment-diffusion *** generates two position matrices in a progressive manner to achieve an efficient random exchange of pixel positions,assignment is carried through on the image pixels of the permutated image to entirely remove the original image information,strengthening the relationship between permutation and diffusion,and loop diffusion in two different directions can use subtle changes of pixels to affect the whole *** random key and plain-image SHA-512 hash values are used to produce an additional key,which is then utilized to figure out the permutation parameters and the initial value of a chaotic *** experimental results with the average NPCR=99.6094%(NPCR:number of pixels change rate),average UACI=33.4638%(UACI:unified average changing intensity),100%pass rate of the targets in the test set,the average correlation coefficient is 0.00075,and the local information entropy is 7.9025,which shows that the algorithm is able to defend against a variety of illegal attacks and provide more trustworthy protection than some of the existing state-of-the-art algorithms.

关键词： chaos memristive hyperchaotic map remote sensing SHA-512 image encryption RS-IEA

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： Qiang-Qiang liu shu-Ting liu Ying-Guang Li Xu liu Xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite *** embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the *** this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is *** the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating *** addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the *** method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Characteristics and Risk Factors for Pediatric Sepsis

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Current Medical Science 2024年第3期44卷 648-656页

作者： Yong-bing ZHU Tong-lin liu Qi DAI shu-fan liu Peng XIONG Hao HUANG Yi yuan Tian-nan ZHANG Yu CHEN Department of Pediatric Intensive Care Unit Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective Sepsis is considered a major cause of health loss in children and had high mortality and ***,there is no reliable model for predicting the prognosis of pediatric patients with *** study aimed to analyze the clinical characteristics of sepsis in children and assess the risk factors associated with poor prognosis in pediatric sepsis patients to identify timely interventions and improve their *** This study analyzed the clinical indicators and laboratory results of septic patients hospitalized in the Pediatric Intensive Care Unit of Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology,China,from January 1,2019,to December 31,*** factors for sepsis were identified by logistic regression *** A total of 355 children with sepsis were enrolled,with 333 children(93.8%)in the good prognosis group,and 22 children(6.2%)in the poor prognosis *** them,there were 255 patients(71.8%)in the sepsis group,and 100 patients(28.2%)in the severe sepsis *** length of hospital stay in the poor prognosis group was longer than that in the good prognosis group(P0.05),and the platelet(PLT),albumin(ALB),and hemoglobin(Hb)levels were lower in the poor prognosis group(P<0.01).The IL-8 levels in the severe sepsis group were higher than those in the sepsis group(P<0.05).Multiple logistic regression analysis suggested that lower Hb levels,ALB levels,peak PLT counts,and higher IL-1βlevels were independent risk factors for poor prognosis in children with *** Lower Hb,ALB,and PLT counts and elevated IL-1βare independent risk factors for poor prognosis in children with sepsis.

关键词： pediatric sepsis inflammation severity prognosis risk factors

Synergic action of linear dispersion, second-order nonlinearity, and third-order nonlinearity in shaping the spectral profile of a femtosecond pulse transporting in a lithium niobate crystal

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Photonics Research 2024年第4期12卷 774-783页

作者： LIHONG HONG yuanyuan liu ZHI-yuan LI State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

We present a detailed theoretical and numerical analysis on the temporal-spectral-spatial evolution of a highpeak-power femtosecond laser pulse in two sets of systems:a pure lithium niobate(LN)plate and a periodically poled lithium niobate(PPLN)*** develop a modified unidimensional pulse propagation model that considers all the prominent linear and nonlinear processes and carried out the simulation process based on an improved split-step Fourier transformation *** theoretically analyze the synergic action of the linear dispersion effect,the second-order nonlinearity(2nd-NL)second-harmonic generation(SHG)effect,and the third-order nonlinearity(3rd-NL)self-phase modulation(SPM)effect,and clarify the physical mechanism underlying the peculiar and diverse spectral broadening patterns previously reported in LN and PPLN thin plate *** analysis and discussion provides a deeper insight into the synergetic contribution of these linear and nonlinear effects brought about by the interaction of a femtosecond laser pulse with the LN nonlinear crystal and helps to draw a picture to fully understand these fruitful optical physical processes,phenomena,and laws.

关键词： pulse nonlinearity lithium

Impact of Carbon Chain Structures in the Backbone on the Flexibility of Modified Polyarylene Sulfide Resins: Molecular Dynamics Simulations and Mesoscopic Analysis

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Chinese Journal of Polymer Science 2024年第4期42卷 544-557页

作者： Chi Zhang Rong liu Jing-yuan liu Wen-Wei Jiang Key Laboratory of Fine Chemical Engineering and Functional Materials School of Chemical EngineeringSichuan UniversityChengdu610065China

In the domain of high-performance engineering polymers, the enhancement of mechanical flexibility in poly(phenylene sulfide) (PPS) resins has long posed a significant challenge. A novel molecular structure, designated as PP-He-IS, wherein imide rings and an aliphatic hexylene chain are covalently incorporated into the PPS backbone to enhance its flexibility, is introduced in this study. Molecular dynamics (MD) simulations are employed to systematically explore the effects of diversifying the backbone chain structures by substituting phenyl units with alkyl chains of varying lengths, referred to as PP-A-IS where “A” signifies the distinct intermediary alkyl chain configurations. Computational analyses reveal a discernable decrement in the glass transition temperature (Tg) and elastic modulus, counterbalanced by an increment in yield strength as the alkyl chain length is extended. Notably, the PP-He-IS variant is shown to exhibit superior yield strength while simultaneously maintaining reduced elastic modulus and Tg values, positioning it as an advantageous candidate for flexible PPS applications. Mesoscopic analyses further indicate that structures such as PP-He-IS, PP-Pe-IS, and PP-Bu-IS manifest remarkable flexibility, attributable to the presence of freely rotatable carbon-carbon single bonds. Experimental validation confirms that a melting temperature of 504 K which is lower than that of conventional PPS, and lower crystallinity are exhibited by PP-He-IS, thereby affording enhanced processability without compromising inherent thermal stability. Novel insights into the strategic modification of PPS for mechanical flexibility are thus furnished by this study, which also accentuates the pivotal role played by molecular dynamics simulations in spearheading high-throughput investigations in polymer material modifications.

关键词： Molecular dynamics simulations Polyarylene Sulfide Main-chain modifications Flexibility Aliphatic hexylene chain

Two-component dimers of ultracold atoms with center-of-mass-momentum dependent interactions

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Communications in Theoretical Physics 2024年第4期76卷 153-157页

作者： Yaru liu shu Yang Peng Zhang Department of Physics Renmin University of ChinaBeijing 100872China Graduate School of China Academy of Engineering Physics Beijing 100193China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

In a previous paper[***.A95,060701(R)(2017)],we demonstrated that a new type of two-body interaction,which depends on the center of mass(CoM)momentum,can be realized for ultracold atoms via laser-modulated magnetic Feshbach resonance(MFR).Further studies(e.g.L He et al,***.120,045302(2018))show that various interesting phenomena,such as Fulde–Ferrell superfluids,can be induced by scattering between ultracold atoms with this *** this work we investigate the shallow bound states of two ultracold atoms with this type of *** show that when the magnetic field B is below the MFR point B0,two shallow bound states can appear in this ***,a'two-component dimer'or a dimer with pseudo-spin 1/2 can be formed by two ***,the dispersion curve of the dimer may have either single or double minimums in the CoM momentum *** latter case can be explained as a result from significant pseudo-spin-orbital coupling(SOC)*** results show that the ultracold gases with CoM momentum dependent interaction may be a candidate for quantum simulations with ultracold two-component molecules,especially the molecule gases with SOC.

关键词： center-of-mass-momentum dependent interaction Raman-laser modulated MFR two-component dimer

NUDT5 promotes the growth,metastasis,and Warburg effect of IDH wild-type glioblastoma multiforme cells by upregulating TRIM47

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Asian Pacific Journal of Tropical Biomedicine 2024年第2期14卷 82-92页

作者： Zi-Fa Zhang shu-Ming liu Neurosurgery Department Shanxi Bethune HospitalTaiyuanShanxi Province030022China Shanxi Academy of Medical Sciences TaiyuanShanxi province030022China Emergency Department Taiyuan People’s HospitalTaiyuanShanxi Province030021China

Objective:To explore the regulatory mechanism of NUDT5 in glioblastoma multiforme(GBM).Methods:GEPIA database was used to predict the expressions of NUDT5 and tripartite motif family proteins 47(TRIM47)in GBM ***-qPCR and Western blot analyses were performed to examine NUDT5 expression in GBM ***-229 cell proliferation,migration as well as invasion were estimated by CCK-8,colony formation,wound healing,and Transwell assays following interference with *** assay,L-lactic acid kit,glucose detection kit,and ATP detection kit were applied for the detection of glycolysis-related ***-immunoprecipitation experiment was carried out to verify the relationship between NUDT5 and ***:GEPIA database showed that NUDT5 expression was significantly increased in GBM *** the expression of NUDT5 in GBM cells significantly suppressed the viability,proliferation,invasion,migration,and glycolysis of GBM ***,TRIM47 was highly expressed in GBM cells and interacted with *** of TRIM47 partially reversed the inhibitory effect of NUDT5 downregulation on the proliferation,metastasis,and glycolysis of GBM ***:NUDT5 promotes the growth,metastasis,and Warburg effect of GBM cells by upregulating *** NUDT5 and TRIM47 can be used as targets for GMB treatment.

关键词： Glioblastoma multiforme NUDT5 TRIM47 Growth Metastasis Warburg effect