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《布朗库西公寓》四部曲

艺术当代 2022年第5期21卷 30-33页

作者：李青不详

一、框形与空缺(2018年10月)这是我第四次在一块框形的画布上作画,一切已经没那么新鲜。前三次画的都与海景有关:一艘海上的难民船,人物是逆光下的剪影,几乎只画了船头和船尾;一幅是模仿大卫·弗里德里希的海景,海的部分几乎不可见;第... 详细信息

一、框形与空缺(2018年10月)这是我第四次在一块框形的画布上作画,一切已经没那么新鲜。前三次画的都与海景有关:一艘海上的难民船,人物是逆光下的剪影,几乎只画了船头和船尾;一幅是模仿大卫·弗里德里希的海景,海的部分几乎不可见;第三幅是海滩上的一个女人,脸和躯干都缺失了。这三幅画的中心都是空无。

关键词：布朗库西弗里德里希四部曲难民船

The load criteria for ship mechanical noise prediction in low frequencies and experimental validation

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Journal of Ocean Engineering and Science 2023年第3期8卷 278-293页

作者： Xi-An liu De-qing Yang qing Li State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The loading method of the external excitations generated by the equipment directly affects the predicted result of the mechanical noise which should be the same under different excitation forms for the given equipment.In this paper,general load criteria are proposed to define forces/moments as the standard form and convert other forms of loads in the low-frequency domain.As the most typical form to charac-terize equipment excitation,acceleration load loading methods for different conditions are investigated.The equivalent formula between ideal accelerations and generalized forces establishes the first load cri-terion.The second load criterion is proposed to address the issue of an average acceleration loading,in which the phase and amplitude distribution are both absent,and cannot apply to the load identification.The upper and lower limits of the mechanical noise can be determined by the vibroacoustic transfer func-tion of the three load models,and the energy-averaged value is used to represent the mechanical noise.Furthermore,the third criterion is used to handle the case where the acceleration load is given by the results of a bench test.According to the equipment source descriptor invariance,the conversion method is achieved between the bench test and the real ship based on the transfer function of a load model,and the mechanical noise is predicted by an equivalent energy method.Finally,a three-parameter method to quantitatively evaluate the well-fitting of experimental and numerical results,and the load criteria are well validated by underwater acoustic experiments of an experimental model.

关键词： Ships’mechanical noise Load criteria Vibroacoustic transfer functions Underwater acoustic experiments Accelerations load Three-parameter method

Site-specific genome editing in treatment of inherited diseases:possibility,progress,and perspectives

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Medical Review 2022年第5期2卷 471-500页

作者： Chao Huang qing Li Jinsong li Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesNo.1 Sub-Lane XiangshanHangzhou 310024ZhejiangChina State Key Laboratory of Cell Biology Shanghai Key Laboratory of Molecular AndrologyCAS Center for Excellence in Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyChinese Academy of SciencesUniversity of Chinese Academy of SciencesNo.320 Yueyang RoadShanghai 200031China Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiangChina State Key Laboratory of Cell Biology Shanghai Key Laboratory of Molecular AndrologyCAS Center for Excellence in Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina

Advancements in genome editing enable permanent changes of DNA sequences in a site-specific manner,providing promising approaches for treating human genetic disorders caused by gene mutations.Recently,genome editing has been applied and achieved significant progress in treating inherited genetic disorders that remain incurable by conventional therapy.Here,we present a review of various programmable genome editing systems with their principles,advantages,and limitations.We introduce their recent applications for treating inherited diseases in the clinic,including sickle cell disease(SCD),β-thalassemia,Leber congenital amaurosis(LCA),heterozygous familial hypercholesterolemia(HeFH),etc.We also discuss the paradigm of ex vivo and in vivo editing and highlight the promise of somatic editing and the challenge of germline editing.Finally,we propose future directions in delivery,cutting,and repairing to improve the scope of clinical applications.

关键词： clinical applications genome editing inherited diseases mutations principles.

High tension cyclic hydrocarbons synthesized from biomass-derived platform molecules for aviation fuels in two steps

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Green Energy & Environment 2023年第1期8卷 331-337页

作者： Zhanchao li Yizhuo Wang qing Li liqing Xu Hong Wang Frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an710054China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710054China

Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging,especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived chemicals.Herein,we report the synthesis of a series of ring structure biofuels in two steps by a combination of a solvent-free Michael-cyclization reaction and a hydrodeoxygenation(HDO)reaction from lignocellulosederived 5,5-dimethyl-1,3-cyclohexanedione.These biofuels are obtained with high overall yields up to 90%,which exhibit high densities of 0.81 g cm^(-3)-0.88 g cm^(-3)and high volumetric neat heat of combustion(VNHOC)values of 36.0 MJ L^(-1)-38.6 MJ L^(-1).More importantly,bridged-ring structure hydrocarbons can also be achieved in two steps by a combination of a Robinson annulation reaction and an HDO reaction to afford the final products at high overall yields up to 90%.The bridged-ring structure products have comparable high densities and high VNHOC values to the best artificial fuel JP-10(0.94 g cm^(-3)and 39.6 MJ L^(-1)).The results demonstrate a promising way for the synthesis of high-density aviation fuels with different fuel properties at high yields.

关键词： Biofuels 5,5-Dimethyl-1,3-cyclohexanedione Solvent-free Michael-cyclization Robinson annulation Green reaction

Observer-Based Path Tracking Controller Design for Autonomous Ground Vehicles With Input Saturation

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 749-761页

作者： Heng Wang Tengfei Zhang Xiaoyu Zhang qing Li School of Automation and Electrical Engineering and also with the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China School of Automation and Electrical Engineering and also with the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083

This paper investigates the problem of path tracking control for autonomous ground vehicles(AGVs),where the input saturation,system nonlinearities and uncertainties are considered.Firstly,the nonlinear path tracking system is formulated as a linear parameter varying(LPV)model where the variation of vehicle velocity is taken into account.Secondly,considering the noise effects on the measurement of lateral offset and heading angle,an observer-based control strategy is proposed,and by analyzing the frequency domain characteristics of the derivative of desired heading angle,a finite frequency H_∞index is proposed to attenuate the effects of the derivative of desired heading angle on path tracking error.Thirdly,sufficient conditions are derived to guarantee robust H_∞performance of the path tracking system,and the calculation of observer and controller gains is converted into solving a convex optimization problem.Finally,simulation examples verify the advantages of the control method proposed in this paper.

关键词： Autonomous ground vehicles(AGVs) H_∞index input saturation observer-based controller path tracking control

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李庆短跑训练理念研究

体育科学 2018年第2期38卷 55-64,90页

作者：姜自立李庆国家体育总局体育科学研究所北京100061 清华大学体育部北京100084

采用文献资料调研、实地跟踪和专家访谈等方法对我国著名短跑教练李庆的训练理念进行了深入和系统的分析,结果表明,李庆主张"以长带短"的短跑训练理念,在速度训练中重视神经-肌肉系统的兴奋性、重视神经对肌肉的控制以及动作幅度和节奏... 详细信息

采用文献资料调研、实地跟踪和专家访谈等方法对我国著名短跑教练李庆的训练理念进行了深入和系统的分析,结果表明,李庆主张"以长带短"的短跑训练理念,在速度训练中重视神经-肌肉系统的兴奋性、重视神经对肌肉的控制以及动作幅度和节奏的变化,在速度耐力训练中重视平均强度和量的积累,主张"高量"模式,在力量训练中重视跳跃练习,强调发力速度,注重力量素质的平衡发展与转化,在技术训练中注重"扬长避短",重视全程速度节奏,追求最佳步长-身高比,强调技术动作的简洁、流畅和放松,在一般身体训练中重视髋关节的灵活性及其附属肌群的力量和有氧能力的发展,在年周期、中周期和微周期的构建中分别遵循"双高峰""先基后专"和"跳跃式"的负荷原则,并将"防伤控病"视为短跑训练的首要任务。

关键词：李庆短跑训练理念速度训练速度耐力训练力量训练

AdaptNF: Adaptive service chain scheduling with stateless migration and NF consolidation

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Digital Communications and Networks 2023年第2期9卷 462-472页

作者： qing Li He Huang Yong Jiang Jingpu Duan Peng Cheng Laboratory Shenzhen518000China Tsinghua Shenzhen International Graduate School Shenzhen10003China Southern University of Science and Technology Shenzhen14325China

The combination of network function virtualization and software-defined networking allows various network functions to process flows according to their characteristics and requirements.Due to the highly dynamic nature of the workload,the network infrastructure needs to properly schedule the underlying resources in order to respond to workload changes in a timely manner.However,the existing NFV platform lacks a comprehensive solution for how to scale under workload variation,which may seriously hurt the overall system performance.To improve the scalability of the NFV platform and ensure consistent high performance under dynamic workloads,we propose AdaptNF,a novel NFV platform designed to support a combination of course-grained and fine-grained resource scheduling strategies.To deal with resource imbalance,which is the essential scheduling problem that leads to insufficient NFV performance,AdaptNF adopts a novel algorithm that can efficiently balance the workload among multiple network function instances through stateless flow migration.Our controlled experiments show that the AdaptNF scheme can optimize resource allocation and ensure outstanding performance after scaling.In terms of network throughput and latency,AdaptNF significantly improves the performance of the underlying NFV platform.

关键词： Network function virtualization Software-defined networking Service chain Flow migration Dynamic scale

Optimal Synchronization Control of Heterogeneous Asymmetric Input-Constrained Unknown Nonlinear MASs via Reinforcement Learning

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 520-532页

作者： lina Xia qing Li Ruizhuo Song Hamidreza Modares Beijing Engineering Research Center of Industrial Spectrum Imaging School of Automation and Electrical EngineeringUniversity of Science and Technology Beijing IEEE the Department of Mechanical Engineering Michigan State University

The asymmetric input-constrained optimal synchronization problem of heterogeneous unknown nonlinear multiagent systems(MASs)is considered in the paper.Intuitively,a state-space transformation is performed such that satisfaction of symmetric input constraints for the transformed system guarantees satisfaction of asymmetric input constraints for the original system.Then,considering that the leader’s information is not available to every follower,a novel distributed observer is designed to estimate the leader’s state using only exchange of information among neighboring followers.After that,a network of augmented systems is constructed by combining observers and followers dynamics.A nonquadratic cost function is then leveraged for each augmented system(agent)for which its optimization satisfies input constraints and its corresponding constrained Hamilton-Jacobi-Bellman(HJB)equation is solved in a data-based fashion.More specifically,a data-based off-policy reinforcement learning(RL)algorithm is presented to learn the solution to the constrained HJB equation without requiring the complete knowledge of the agents’dynamics.Convergence of the improved RL algorithm to the solution to the constrained HJB equation is also demonstrated.Finally,the correctness and validity of the theoretical results are demonstrated by a simulation example.

关键词： Asymmetric input-constrained heterogeneousnonlinear multiagent systems(MASs) Hamilton-Jacobi-Bellman(HJB)equation novel observer reinforcement learning(RL)

A novel hydrogel with glucose-responsive hyperglycemia regulation and antioxidant activity for enhanced diabetic wound repair

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Nano Research 2022年第6期15卷 5305-5315页

作者： Zejun Xu Guiting liu qing Li Jun Wu School of Biomedical Engineering Sun Yat-sen UniversityShenzhen 518107China Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Sun Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhou 510120China The State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China School and Hospital of Stomatology Cheeloo College of MedicineShandong UniversityJinan 250012China

Enhanced diabetic wound repair remained a global challenge.Herein,we reported a novel hydrogel with glucose-responsive hyperglycemia regulation and antioxidant activity for enhanced diabetic wound repair.In this study,gallic acid(GA)with strong antioxidant activity was grafted onto chitosan(CS)chains by one-step synthesis,and then incorporated into poly(ethylene glycol)diacrylate(PEG-DA)hydrogel matrix to obtain a novel antioxidant hybrid hydrogel(PEG-DA/CS-GA).Meanwhile,polyethyleneimine(PEI)was modified with a unique glucose-sensitive phenylboronic acid(PBA)molecule to load insulin(PEIPBA/insulin nano-particles,PEI-PBA/insulin NPs),which could be immobilized in the PEG-DA/CS-GA hybrid hydrogel by the formation of dynamic borate bond between the phenylboronic acid groups on the PEI-PBA and the polyphenol groups on the CSGA.The results indicated that the PEG-DA/PEI-PBA/insulin/CS-GA(PPIC)hydrogel platform not only had remarkable biocompatibility,but also displayed extraordinary antioxidant properties(DPPH scavenging rate>95.0%),and effectively protected cells from oxidative damage(decreased MDA levels,increased Superoxide dismutase(SOD)levels and stable GSH/GSSG levels).Meanwhile,the PPIC hydrogel also exhibited unique glucose-responsive insulin release characteristics,and effectively regulated the blood glucose level.The in vitro and in vivo results demonstrated that our PPIC hydrogel could promoted angiogenesis(increased VEGF and CD 31 expression),reshaped the inflammatory microenvironment(decreased IL-6 and increased IL-10 level),and achieved wound closure within 20 days.All these results strongly indicated that the PPIC hydrogel represented a tough and efficient platform for diabetic wound treatment.

关键词： diabetic wound glucose responsive antioxidation hyperglycemia regulation insulin