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Nonlinear robust adaptive control for bidirectional stabilization system of all-electric tank with unknown actuator backlash compensation and disturbance estimation

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Defence Technology（防务技术） 2024年第2期32卷 144-158页

作者： Shusen yuan Wenxiang deng Jianyong Yao Guolai Yang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

Since backlash nonlinearity is inevitably existing in actuators for bidirectional stabilization system of allelectric tank,it behaves more drastically in high maneuvering environments.In this work,the accurate tracking control for bidirectional stabilization system of moving all-electric tank with actuator backlash and unmodeled disturbance is solved.By utilizing the smooth adaptive backlash inverse model,a nonlinear robust adaptive feedback control scheme is presented.The unknown parameters and unmodelled disturbance are addressed separately through the derived parametric adaptive function and the continuous nonlinear robust term.Because the unknown backlash parameters are updated via adaptive function and the backlash effect can be suppressed successfully by inverse operation,which ensures the system stability.Meanwhile,the system disturbance in the high maneuverable environment can be estimated with the constructed adaptive law online improving the engineering practicality.Finally,Lyapunov-based analysis proves that the developed controller can ensure the tracking error asymptotically converges to zero even with unmodeled disturbance and unknown actuator backlash.Contrast co-simulations and experiments illustrate the advantages of the proposed approach.

关键词： Bidirectional stabilization system Robust control Adaptive control Backlash inverse Disturbance estimation

Synthesis of multifunctional additives for solid propellants:Structure,properties and mechanism

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Defence Technology（防务技术） 2024年第3期33卷 308-316页

作者： Pingan Zhang Lina Sun Jianmin yuan Jianru deng College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082PR China College of Material Science and Engineering Hunan UniversityChangsha 410082PR China Hu Bei Sanjiang Aerospace Jianghe Chemical Technology Co. LtdYichang 444200PR China

To simplify the composite propellant formulation and address the current issue of the single-functionality present in existing additives,the multi-cyano,amine-based polybutadiene(AEHTPB-CN)was prepared based on AEHTPB by adopting appropriate synthesis strategies.By replacing 10% of HTPB binder in the propellant formulation,it can effectively enhance the interfacial bond strength between the propellant binder matrix and solid fillers(AP(ammonium perchlorate)and RDX(cyclotrimethylene-trinitramine)),the mechanical properties of the HTPB/AP/RDX/Al propellant were superior to blank control propellant with an improvement of 35.4% in tensile strength,62.0% enhancement in elongation at break,and reduce the propellant burn rate by 10.7% with any energy loss.The function mechanism of AEHTPB-CN was systematically elucidated through experiments and computer simulation techniques.The results show that the tertiary amine group in AEHTPB-CN can react with AP to form ammonium ionic bonds,and the hydroxyl and cyano groups can form hydrogen bonding interactions with AP,which enables AEHTPB-CN to be firmly adsorbed on the AP surface through chemical and physical interactions.For RDX,the interfacial bonding effect of AEHTPB-CN is attributed to their ability to form C-H···N≡C weak hydrogen bonding interaction between the cyano group and RDX methylene group.

关键词： Hydroxyl-terminated polybutadiene(HTPB) HTPB propellant Chemical modification Bonding agent Mechanism

Metarelation2vec:A Metapath-Free Scalable Representation Learning Model for Heterogeneous Networks

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Tsinghua Science and Technology 2024年第2期29卷 553-575页

作者： Lei Chen yuan Li Yong Lei Xingye deng School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

Metapaths with specific complex semantics are critical to learning diverse semantic and structural information of heterogeneous networks(HNs)for most of the existing representation learning models.However,any metapaths consisting of multiple,simple metarelations must be driven by domain experts.These sensitive,expensive,and limited metapaths severely reduce the flexibility and scalability of the existing models.A metapath-free,scalable representation learning model,called Metarelation2vec,is proposed for HNs with biased joint learning of all metarelations in a bid to address this problem.Specifically,a metarelation-aware,biased walk strategy is first designed to obtain better training samples by using autogenerating cooperation probabilities for all metarelations rather than using expert-given metapaths.Thereafter,grouped nodes by the type,a common and shallow skip-gram model is used to separately learn structural proximity for each node type.Next,grouped links by the type,a novel and shallow model is used to separately learn the semantic proximity for each link type.Finally,supervised by the cooperation probabilities of all meta-words,the biased training samples are thrown into the shallow models to jointly learn the structural and semantic information in the HNs,ensuring the accuracy and scalability of the models.Extensive experimental results on three tasks and four open datasets demonstrate the advantages of our proposed model.

关键词： metarelation random walk heterogeneous network metapath representation learning

Constructions of optimal binary locally repairable codes via intersection subspaces

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Science China(Information Sciences) 2024年第6期67卷 418-432页

作者： Wenqin ZHANG deng TANG Chenhao YING yuan LUO School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Locally repairable codes（LRCs）, which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b（b 3） and minimum distance d 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d 6 and locality 2b.

关键词： locally repairable codes disjoint local repair groups distributed storage systems intersection subspaces direct sum

Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction of emerging contaminants

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 49-60页

作者： Yuhang Liu Wenxuan deng Xiaojun Wu chun Hu Lai Lyu Key Laboratory for Water Quality and Conservation of the Pearl River Delta(Ministry of Education) Institute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China

Effective removal of emerging contaminants(ECs)to minimize their impacts on human health and the natural environment is a global priority.For the removal of ECs in water,we fabricated a seaweed spherical microsphere catalyst with Cu cation-πstructures by in situ doping of Cu species and ascorbic acid in mesoporous silica(Cu-C-MSNs)via a hydrothermal method.The results indicate that bisphenol A(BPA)is substantially degraded within 5 min under natural conditions,with its biological toxicity considerably weakened.Moreover,industrial wastewater could also be effectively purified by Cu-C-MSNs/H2O2 system.The presence of metal sites and the complexation of ECs via cation-πinteraction andπ-πstacking on the catalyst surface were directly responsible for the polarization distribution of electrons,thus activating H2O2 and dissolved oxygen(DO).The removal of contaminants could be attributed primarily to 1)the activation of H2O2 into•OH to attack the contaminants and 2)self-cleavage because of the transfer of electrons from the contaminants to the catalysts.This study provides an innovative solution for the effective treatment of ECs and has positive implications for easing global environmental crises.

关键词： Cation-πstructures Polarization electric field Fenton-like process Contaminants cleavage

The Perturbed Compound Poisson Risk Model with Proportional Investment

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 109-128页

作者： Nai-dan deng chun-wei Wang Jia-en Xu School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China

In this paper, the insurance company considers venture capital and risk-free investment in a constant proportion. The surplus process is perturbed by diffusion. At first, the integro-differential equations satisfied by the expected discounted dividend payments and the Gerber-Shiu function are derived. Then, the approximate solutions of the integro-differential equations are obtained through the sinc method. Finally, the numerical examples are given when the claim sizes follow different distributions. Furthermore, the errors between the explicit solution and the numerical solution are discussed in a special case.

关键词： expected discounted dividend payments lognormal distribution proportional investment perturbed risk model sinc numerical method

Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens

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Food Science and Human Wellness 2024年第3期13卷 1567-1577页

作者： yuan yuan Shun Zhong Zeyuan deng Guangyan Li Jinwu Zhang Hongyan Li State Key Laboratory of Food Science and Resources Nanchang UniversityNanchang 330047China Nanchang Tongxin Zichao Biological Engineering Co. Ltd.Nanchang 330052China

The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods.

关键词： Bee pollen Nutrients Wall disruption Phenolic compounds In vitro digestion

Regulation of AMPK activation by extracellular matrix stiffness in pancreatic cancer

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Genes & Diseases 2024年第3期11卷 338-350页

作者： Xin Xu yuan Fang Somaira Nowsheen Ye-Xiong Li Zhenkun Lou Min deng State Key Laboratory of Molecular Oncology and Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of General Surgery Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China Department of General Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Department of Dermatology University of California San DiegoSan DiegoCA 92093USA Department of Oncology Mayo ClinicRochesterMN 55905USA

The adenosine monophosphate(AMP)-activated protein kinase(AMPK)sits at a cen-tral node in the regulation of energy metabolism and tumor progression.AMPK is best known to sense high cellular ADP or AMP levels,which indicate the depletion of energy stores.Previous studies have shown that the low expression of phosphorylated AMPK is associated with a poor prognosis of pancreatic cancer.In this study,we report that AMPK is also highly sensitive to extracellular matrix(ECM)stiffness.We found that AMPK is activated in cells when cultured under low ECM stiffness conditions and is functionally required for the metabolic switch induced by ECM stiffness.This regulation of AMPK requires the Hippo kinases but not LKB1/CaMKKp.Hippo kinases directly phosphorylate AMPKa at Thr172 to activate AMPK at low ECM stiffness.Furthermore,we found AMPK activity is inhibited in patients with pancreatic ductal adenocarcinoma(PDAC)with high ECM stiffness and is associated with a poor survival outcome.The activation of Hippo kinases by ROCK inhibitor Y-27632 in combination with the mitochondrial inhibitor metformin synergistically activates AMPK and dramatically inhibits PDAC growth.Together,these findings establish a novel model for AMPK regulation by the mechanical properties of ECMs and provide a rationale for simultaneously targeting the ECM stiffness-Hippo kinases-AMPK signaling and low glucose-LKB1-AMPK signaling pathways as an effective therapeutic strategy against PDAC.

关键词： AMPKactivity Cellularmetabolic switch ECM stiffness Hippokinase signaling Pancreaticductal adenocarcinoma

Timing theory integrated nursing combined behavior change integrated theory of nursing on primiparous influence

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World Journal of Clinical Cases 2024年第2期12卷 293-301页

作者： Yan-Xia He Yang Lv Ting-Ting Lan Fang deng yuan-yuan Zhang Department of Obstetrics and Gynecology Wuhan Children’s HospitalWuhan 430015Hubei ProvinceChina Center for Reproductive Medicine Department of Obstetrics and GynecologySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to enhance the psychological well-being and overall quality of life for primipara,while also furnishing healthcare providers with efficacious interventions to tackle the psychological and physiological obstacles encountered during the stages of pregnancy and postpartum.AIM To explore the effect of timing theory combined with behavior change on selfefficacy,negative emotions and quality of life in patients with primipara.METHODS A total of 80 primipara cases were selected and admitted to our hospital between August 2020 and May 2022.These cases were divided into two groups,namely the observation group and the control group,with 40 cases in each group.The nursing interventions differed between the two groups,with the control group receiving routine nursing and the observation group receiving integrated nursing based on the timing theory and behavior change.The study aimed to compare the pre-and post-nursing scores of Chinese Perceived Stress Scale(CPSS),Edinburgh Postpartum Depression Scale(EPDS),Self-rating Anxiety Scale(SAS),breast milk knowledge,self-efficacy,and SF-36 quality of life in both groups.RESULTS After nursing,the CPSS,EPDS,and SAS scores of the two groups was significantly lower than that before nursing,and the CPSS,EPDS,and SAS scores of the observation group was significantly lower than that of the control group(P=0.002,P=0.011,and P=0.001 respectively).After nursing,the breastfeeding knowledge mastery,selfefficacy,and SF-36 quality of life scores was significantly higher than that before nursing,and the breastfeeding knowledge mastery(P=0.013),self-efficacy(P=0.008),and SF-36 quality of life(P=0.011)scores of the observation group was significantly higher than that of the control group.CONCLUSION The integration of timing theory and behavior change integrated theory has been found to be a

关键词： Timing theory Behavior change Primipara Bad mood Quality of life