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Physics-informed deep Koopman operator for Lagrangian dynamic systems

Science China(Information Sciences) 2024年第09期67卷 146-163页

作者： Xuefeng WANG Yang CAO Shaofeng CHEN yu kang Department of Automation University of Science and Technology of China State Key Laboratory of Fire Science University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China

Accurate mechanical system models are crucial for safe and stable control. Unlike linear systems,Lagrangian systems are highly nonlinear and difficult to optimize because of their unknown system *** research thus used deep neural networks to generate linear models of original systems by mapping nonlinear dynamic systems into a linear space with a Koopman observable function encoder. The controller then relies on the Koopman linear model. However, without physical information constraints, ensuring control consistency between the original nonlinear system and the Koopman system is tough, as the learning process of the Koopman observation function is unsupervised. This paper thus proposes a two-stage learning algorithm that uses structural subnetworks to build a physics-informed network topology to simultaneously learn the Koopman observable functions and the system energy representation. In the Koopman matrix learning session, a quadratic-constrained optimization problem is solved to ensure that the Koopman representation satisfies the energy difference matching hard constraint. The proposed energy-preserving deep Lagrangian Koopman(EPDLK) framework effectively represents the dynamics of the Lagrangian system while ensuring control consistency. The effectiveness of EPDLK is compared with those of various Koopman observable function construction methods in multistep prediction and trajectory tracking tasks. EPDLK achieves better control consistency by guaranteeing energy difference matching, which facilitates the application of the control law generated on the Koopman system directly to the original nonlinear Lagrangian system.

关键词： Koopman operator Lagrangian physics-informed nonlinear model predictive control (MPC)

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Autonomous multi-drone racing method based on deep reinforcement learning

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Science China(Information Sciences) 2024年第8期67卷 35-48页

作者： yu kang Jian DI Ming LI yunbo ZHAO yuhui WANG Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Racing drones have attracted increasing attention due to their remarkable high speed and excellent maneuverability. However, autonomous multi-drone racing is quite difficult since it requires quick and agile flight in intricate surroundings and rich drone interaction. To address these issues, we propose a novel autonomous multi-drone racing method based on deep reinforcement learning. A new set of reward functions is proposed to make racing drones learn the racing skills of human experts. Unlike previous methods that required global information about tracks and track boundary constraints, the proposed method requires only limited localized track information within the range of its own onboard sensors. Further, the dynamic response characteristics of racing drones are incorporated into the training environment, so that the proposed method is more in line with the requirements of real drone racing scenarios. In addition, our method has a low computational cost and can meet the requirements of real-time racing. Finally, the effectiveness and superiority of the proposed method are verified by extensive comparison with the state-of-the-art methods in a series of simulations and real-world experiments.

关键词： autonomous multi-drone racing deep reinforcement learning Markov game racing drone sim-to-real

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Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang yu-kang Lou Lin Peng yuan Peng Meng-Meng Wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

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Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2018-2022

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Advances in Climate Change Research 2024年第2期15卷 297-311页

作者： yu-Long kang Shi-Chang kang Wan-Qin GUO Tao CHE Zong-Li JIANG Zhen-Feng WANG Qiang-Qiang XU Cheng-De YANG State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100083China Key Laboratory of Remote Sensing of Gansu Province Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

Ice sheet serves as a crucial indicator for assessing climate *** loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface ***,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal *** study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2 satellites during *** results indicate that the glacier area reduced by approximately 166.1±44.2 km^(2)(-0.2%±0.1%per year)during the study period,with an acceleration after 2020(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern *** maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2021 were the highest(exceeded 4210 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing *** glacier G012158E47018N,McNeile Glacier,glacier G299637E64094S and Drygalski Glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their *** results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere ***,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios.

关键词： Glacier area Seasonal ice speed Sentinel 1&2 Northern Antarctic Peninsula Ice-ocean-atmosphere processes

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Modelling and Optimizing Motherboard Functional Testing in Laptop Manufacturing

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Journal of Systems Science & Complexity 2024年

作者： kang yu BAI Peng WANG kangcheng ZHAO yunbo DONG Shaojie Department of Automation & Institute of Advanced Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China

Functional testing is key to fulfill quality control in laptop manufacturing and is of great economic value. However, due to the unavailability of practical data, mathematical model and systematic perspective, it has barely been touched from the academic community to date. For the first time,this work provides technical understanding of the key principles of functional testing, mathematically models the general framework, elucidates existing testing strategy under the proposed framework and model, and finally proposes a specified optimization strategy which outperforms existing *** work lays the model foundation for the further optimization of functional testing, and can be regarded as a good example of how a systematic approach can solve practical industrial challenges.

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Perinatal prevalence of birth defects in the Mainland of China,2000–2021:a systematic review and meta-analysis

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World Journal of Pediatrics 2024年第7期20卷 669-681页

作者： Liang-yu kang Zi-Rui Guo Wei-Jing Shang Gui-Ying Cao Yi-Ping Zhang Qiao-Mei Wang Hai-Ping Shen Wan-Nian Liang Min Liu Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityNo.38Xueyuan RoadHaidian DistrictBeijing100191China Vanke School of Public Health Tsinghua UniversityNo.1Tsinghua GardenHaidian DistrictBeijing100084China Department of Maternal and Child Health National Health Commission of the People’s Republic of ChinaNo.1Xizhimenwai South RoadXicheng DistrictBeijingChina Institute of Healthy China Tsinghua UniversityNo.1Tsinghua GardenHaidian DistrictBeijing100084China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of Education BeijingNo.38Xueyuan RoadHaidian DistrictBeijing100191China

Background Although birth defects are of great concern globally,the latest national prevalence has not yet been quantified in *** conducted a systematic review and meta-analysis to estimate the perinatal prevalence of birth defects in the Mainland of China between 2000 and *** We performed a systematic literature search of six databases for relevant articles published between January 1,2000,and March 1,*** included published studies that reported data on the perinatal prevalence of birth defects in the Mainland of *** DerSimonian and Laird random-effects models were used to estimate the pooled prevalence and its 95%confidence interval(CI).We also conducted subgroup analyses and univariable meta-regressions to explore differences in prevalence by time period,geographic region,and other *** We included 254 studies reporting the perinatal prevalence of birth defects and 86 studies reporting only the prevalence of specific types of birth *** on 254 studies covering 74,307,037 perinatal births and 985,115 cases with birth defects,the pooled perinatal prevalence of birth defects was 122.54(95%CI 116.20–128.89)per 10,000 perinatal births in the Mainland of China during 2000–***,the perinatal prevalence of birth defects increased from 95.60(86.51–104.69)per 10,000 in 2000–2004 to 208.94(175.67–242.22)per 10,000 in 2020–*** were also significant disparities among different geographical *** heart defects(33.35 per 10,000),clefts of the lip and/or palate(13.52 per 10,000),polydactyly(12.82 per 10,000),neural tube defects(12.82 per 10,000),and inborn errors of metabolism(11.41 per 10,000)were the five most common types of birth *** perinatal prevalence among males was significantly higher than that among females(β=2.44×10^(−3),P=0.003);a higher perinatal prevalence of birth defects was observed among perinatal births whose mothers were≥35 years(β=4.34×10^(−3),P<0.001).Conclusion Compreh

关键词： Birth defects China Perinatal Prevalence

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两山水客:19世纪初的职业贩运人、委托经营与跨区贸易

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中国经济史研究 2024年第5期 61-77页

作者：余康新加坡国立大学亚洲研究所新加坡119260

明中期以后,南方各地替有资本者贩运货物的流动商人随着跨区贸易发展而日趋职业化,并成为店号运营的重要组成部分,被称为“水客”。依凭常玉大路和本地油货,乾隆时期浙赣边界的两山地区聚集了一批利用水客从事跨区贩运的徽商油号。和其... 详细信息

明中期以后,南方各地替有资本者贩运货物的流动商人随着跨区贸易发展而日趋职业化,并成为店号运营的重要组成部分,被称为“水客”。依凭常玉大路和本地油货,乾隆时期浙赣边界的两山地区聚集了一批利用水客从事跨区贩运的徽商油号。和其他地区一样,当地店号任用水客的方式有支薪长期聘用和委托经营两种。至19世纪初,自然灾害等因素造成当地店号支薪聘用水客的模式难以维持。商号通过设立独立核算的水客分号,变个体支薪聘用为分号委托经营,以提高水客在贩运中的自主性与积极性,从而保证商号在市场中能继续生存与获利。两山水客的案例表明贩运的职业化与委托经营的制度化是商号克服不利运输条件、应对经营危机,进而维持跨区贸易的重要手段。对于像两山水客一样的职业贩运人和相关贸易线的讨论,或可成为学界进一步探索中国市场问题的新视角。

关键词：水客徽商职业贩运人委托经营跨区贸易

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新型球形高纯度介孔硅胶复合材料在茂金属聚乙烯催化剂中的应用

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现代化工 2024年第1期44卷 188-193页

作者：亢宇中国石油化工股份有限公司北京化工研究院北京100013

以工业原料水玻璃和硫酸为主要原料,通过球磨打浆技术､高效节能环保除杂质技术和具有尾气回收系统的离心喷雾干燥技术制备出2种日产量12000 kg的用于聚乙烯催化剂的载体高纯度球形介孔硅胶复合材料。2种复合材料在硅胶无序堆积孔中均拥... 详细信息

以工业原料水玻璃和硫酸为主要原料,通过球磨打浆技术､高效节能环保除杂质技术和具有尾气回收系统的离心喷雾干燥技术制备出2种日产量12000 kg的用于聚乙烯催化剂的载体高纯度球形介孔硅胶复合材料。2种复合材料在硅胶无序堆积孔中均拥有有序的介孔孔道且球体度均匀,二氧化硅纯度均在99.5%以上。新型材料在负载聚乙烯催化剂后仍然保持良好微观形貌及其特有的介孔材料孔道结构。高压乙烯聚合小试试验结果表明,2种催化剂对乙烯聚合的活性均高于工业用催化剂的活性,催化反应后得到的聚乙烯粉料的重要物性参数均优于工业用948硅胶粉料。

关键词：介孔硅胶复合材料茂金属乙烯聚合除杂质技术

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Long-term in vivo chimeric cells tracking in non-human primate

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Protein & Cell 2024年第3期15卷 207-222页

作者： Junmo Wu yu kang Xiang Luo Shaoxing Dai yuxi Shi Zhuoyao Li Zengli Tang Zhenzhen Chen Ran Zhu Pengpeng Yang Zifan Li Hong Wang Xinglong Chen Ziyi Zhao Weizhi ji yuyu Niu State Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunming 650500China yunnan Key Laboratory of Primate Biomedical Research Kunming 650500China Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China

Non-human primates(NHPs)are increasingly used in preclinical trials to test the safety and efficacy of biotech-nology ***,given the ethical issues and costs associated with this model,it would be highly advantageous to use NHP cellular models in clinical ***,developing and maintaining the naive state of primate pluripotent stem cells(PSCs)remains difficult as does in vivo detection of PSCs,thus limiting biotech-nology application in the cynomolgus ***,we report a chemically defined,xeno-free culture system for culturing and deriving monkey PSCs in *** cells display global gene expression and genome-wide hypometh-ylation patterns distinct from monkey-primed *** also found expression of signaling pathways components that may increase the potential for chimera *** for biomedical applications,we were also able to integrate bioluminescent reporter genes into monkey PsCs and track them in chimeric embryos in vivo and in *** engineered cells retained embryonic and extra-embryonic developmental ***,we generated a chimeric monkey carrying bioluminescent cells,which were able to track chimeric cells for more than 2 years in living *** study could have broad utility in primate stem cell engineering and in utilizing chimeric monkey models forclinical studies.

关键词： pluripotent stem cells bioluminescence imaging non-human primates

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Exploring the molecular mechanism of Suoquan pill in the treatment of diabetic kidney disease based on network pharmacology,molecular docking,in vitro experiment

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Traditional Medicine Research 2024年第11期9卷 27-37页

作者： Zi-Jie Yan yu kang Shu-Man Liu Fang-yu Wang Man Xiao Yi-Qiang Xie College of Traditional Chinese Medicine Hainan Medical UniversityHaikou 571199China Graduate School Heilongjiang Academy of Traditional Chinese MedicineHarbin 150001China Department of Pharmacology College of PharmacyHainan Medical UniversityHaikou 571199China Key Laboratory of Biochemistry and Molecular Biology Hainan Medical UniversityHaikou 571199China.

Background:Diabetic kidney disease(DKD)is a microvascular complication of diabetes mellitus and is the main cause of end-stage renal *** pills(SQP)has a variety of pharmacological activities and multiple therapeutic effects,and it is used clinically as a basic formula for the treatment of ***:Public databases were used to identify SQP compounds and the potential targets of SQP and DKD.A drug-component-therapeutic target network was ***-protein interaction network analysis,Gene Ontology functional analysis,and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were used to analyse the potential molecular mechanisms of SQP based on common targets of drugs and *** docking simulations were conducted to confirm the binding abity of the core compounds to key *** efficacy and predicted molecular mechanisms of SQP were validated using cell counting kit-8 assay,flow cytometry,and western blotting with HK-2 cells as a ***:Network pharmacology analysis showed that 26 compounds and 207 potential targets of SQP were involved in the treatment of DKD;boldine,denudatin B,pinocembrin,kaempferoid,and quercetin were considered core compounds,and epidermal growth factor receptor(EGFR)and proto-oncogene,non-receptor tyrosine kinase(SRC)were considered key *** Ontology enrichment analysis indicated that protein phosphorylation and negative regulation of apoptotic processes are important biological processes in the treatment of DKD by *** docking confirmed the excellent binding abilities of boldine,denudatin B,kaempferide,and quercetin to EGFR and *** results of in vitro experiments showed that treatment with an ethanolic extract of SQP significantly protected HK-2 cells from high glucose-induced cell *** addition,the SQP ethanol extract inhibited the phosphorylation of EGFR and SRC,suppressed the apoptosis rate,and regulated apoptosis-related proteins in HK-2 cells under hig

关键词： traditional Chinese medicine diabetic kidney disease Suoquan pill network analysis molecular docking

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