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Developmental Gerontology and active Population Aging in China

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China CDC weekly 2023年第8期5卷 184-187页

作者： Xiaoying Zheng Yanan Luo Binbin Su Ping He Chao Guo Yaohua Tian Shasha Han Chen Chen Yiran Wang Jufen Liu Jun Li School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijing MunicipalityChina Department of Global Health School of Public HealthPeking UniversityBeijing MunicipalityChina China Center for Health Development Studies Peking UniversityBeijing MunicipalityChina APEC Health Science Academy Peking UniversityBeijing MunicipalityChina Ministry of Education Key Laboratory of Environment and Health and State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Maternal and Child Health School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health Peking UniversityBeijing MunicipalityChina Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing MunicipalityChina Institute of Economics Chinese Academy of Social SciencesBeijing MunicipalityChina

Population aging is an irreversible process in the development of modern society,which brings challenges to comprehensive modernized social governance.Population aging is a“dualistic”development issue that not only leads to aging of the labor force structure but also creates new demographic dividends.This study describes the core thoughts of developmental gerontology(DG),which provides new insight into the relationship between active aging and comprehensive governance for modernized society.The development of DG will provide a feasible and sustainable path to integrate and coordinate the relationship between population aging,society,and economy.

关键词： aging irreversible active

active sites engineering of Pt/CNT oxygen reduction catalysts by atomic layer deposition

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Journal of Energy Chemistry 2020年第6期29卷 59-66,I0003页

作者： Jie Gan Jiankang Zhang Baiyan Zhang Wenyao Chen Dongfang Niu Yong Qin Xuezhi Duan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina

Understanding carbon-supported Pt-catalyzed oxygen reduction reaction(ORR)from the perspective of the active sites is of fundamental and practical importance.In this study,three differently sized carbon nanotube-supported Pt nanoparticles(Pt/CNT)are prepared by both atomic layer deposition(ALD)and impregnation methods.The performances of the catalysts toward the ORR in acidic media are comparatively studied to probe the effects of the sizes of the Pt nanoparticles together with their distributions,electronic properties,and local environments.The ALD-Pt/CNT catalysts show much higher ORR activity and selectivity than the impregnation-Pt/CNT catalysts.This outstanding ORR performance is ascribed to the well-controlled Pt particle sizes and distributions,desirable Pt^04f binding energy,and the Cl-free Pt surfaces based on the electrocatalytic measurements,catalyst characterizations,and model calculations.The insights reported here could guide the rational design and fine-tuning of carbon-supported Pt catalysts for the ORR.

关键词： Oxygen reduction Pt/CNT catalyst Atomic layer deposition active sites

active Learning Query Strategies for Classification,Regression,and Clustering:A Survey

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Journal of Computer Science & Technology 2020年第4期35卷 913-945页

作者： Punit Kumar Atul Gupta Indian Institute of Information Technology Design and ManufacturingJabalpurMadhya Pradesh 482005India

Generally,data is available abundantly in unlabeled form,and its annotation requires some cost.The labeling,as well as learning cost,can be minimized by learning with the minimum labeled data instances.active learning(AL),learns from a few labeled data instances with the additional facility of querying the labels of instances from an expert annotator or oracle.The active learner uses an instance selection strategy for selecting those critical query instances,which reduce the generalization error as fast as possible.This process results in a refined training dataset,which helps in minimizing the overall cost.The key to the success of AL is query strategies that select the candidate query instances and help the learner in learning a valid hypothesis.This survey reviews AL query strategies for classification,regression,and clustering under the pool-based AL scenario.The query strategies under classification are further divided into:informative-based,representative-based,informative-and representative-based,and others.Also,more advanced query strategies based on reinforcement learning and deep learning,along with query strategies under the realistic environment setting,are presented.After a rigorous mathematical analysis of AL strategies,this work presents a comparative analysis of these strategies.Finally,implementation guide,applications,and challenges of AL are discussed.

关键词： active learning active learning query strategy active classification active regression active clustering deep active learning

active greeting technique: a mother-and-child catheter based technique to facilitate retrograde wire externalization in recanalization of coronary chronic total occlusion

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Science Bulletin 2018年第23期63卷 1565-1569页

作者： Junbo Ge Lei Ge Bin Zhang Xin Zhong Jianying Ma Leisheng Ru Tao Hu Juying Qian 无 Shanghai Institute of Cardiovascular Diseases Zhongshan HospitalFudan UniversityShanghai 200022China Institutes of Biomedical Sciences.Fudan University Shanghai 200032China Department of Cardiology Guangdong Cardiovascular InstituteGuangdong General Hospital Guangzhou510080China Department of Cardiology Bethune International Peace HospitalShzjiazhuang 050082China Department of Cardiology Xijing HospitalXi'an 710032China Chronic Total Occlusion Club China

Although retrograde approach has greatly improved the success rate of percutaneous coronary intervention(PCI) for coronary chronic total occlusion(CTO), retrograde wire externalization still remains challenging and time-consuming in some cases. Cases utilizing ‘‘active Greeting Technique(AGT)", a mother-and-child catheter based technique to facilitate retrograde wire externalization, were extracted from Chronic Total Occlusion Club, China(CTOCC) database. AGT was performed by deep intubation a mother-and-child catheter(GuidezillaTMextension, 4 or 5 Fr inner catheter, and etc.) in combination with either reverse controlled antegrade or retrograde subintimal tracking(CART) technique or retrograde wire crossing technique. A total of 111 patients with 112 CTO lesions treated with this technique were retrospectively analyzed. Reverse CART technique and retrograde wire crossing technique were performed in 90.2% and 9.8% of all procedures. The utilization of GuidezillaTMextension, 4 Fr, and 5 Fr inner catheter accounted for 94.6%, 3.6%, and 1.8%, respectively. Externalization of retrograde wire was successful in all cases. No procedural complications were adjudicated to AGT. Complications independent of AGT included two target vessel perforations and two collateral perforations. No in-hospital major adverse cardiac events were found. AGT is a feasible and safe technique that facilitates retrograde wire externalization.

关键词： Percutaneous coronary intervention Chronic total occlusion Retrograde wire externalization active greeting technique

基于多分辨率和自适应分数阶的active Demons算法

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计算机研究与发展 2018年第12期55卷 2753-2763页

作者：张桂梅郭黎娟熊邦书储珺南昌航空大学计算机视觉研究所南昌330063 南昌航空大学信息工程学院南昌330063

分数阶active Demons(fractional active demons,FAD)算法是图像非刚性配准的有效方法,并且能解决灰度均匀和弱纹理图像配准精度低,优化易陷入局部极小而导致的配准速度缓慢问题,但是该算法中分数阶最佳阶次的寻找需要通过多次实验人工... 详细信息

分数阶active Demons(fractional active demons,FAD)算法是图像非刚性配准的有效方法,并且能解决灰度均匀和弱纹理图像配准精度低,优化易陷入局部极小而导致的配准速度缓慢问题,但是该算法中分数阶最佳阶次的寻找需要通过多次实验人工选取,缺乏阶次自适应性.针对该问题,提出了基于多分辨率和自适应分数阶的active Demons算法,该算法首先根据图像梯度模值和信息熵,构建了自适应分数阶阶次的数学模型,基于该模型自动计算出分数阶的最佳阶次和微分动态模板;然后将多分辨率策略加入到自适应分数阶active Demons算法中,进一步提高了图像配准效率.理论分析和实验结果均表明:提出的算法可用于灰度均匀、弱边缘和弱纹理图像的配准,能根据图像的局部特征自适应计算最佳分数阶阶次,并避免了算法陷入局部最优,从而提高了图像配准的精度和效率.

关键词： R-L(Riemann-Liouville)分数阶微分 active Demons (AD)算法自适应模型多分辨率图像配准

active Thermal Wave Cloak

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Chinese Physics Letters 2020年第12期37卷 6-10页

作者：须留钧黄吉平 Department of Physics State Key Laboratory of Surface Physicsand Key Laboratory of Micro and Nano Photonic Structures(MOE)Fudan UniversityShanghai 200438China

active metamaterials have shown huge advantages to control electromagnetic and acoustic waves.However,how to use active metamaterials to control thermal waves has not been explored,though thermal waves are significant in various fields.To address the problem,here we report an active scheme for thermal wave cloaks.The thermal waves are based on conduction and convection,which are dominated by the Fourier and Darcy laws,respectively.By calculating the propagation of thermal waves in a free space,we can derive the global temperature and pressure distributions.We then apply these calculation results to actively control the boundary temperature and pressure,and active thermal wave cloaks can be obtained.Compared with existing passive schemes to control thermal waves,the present active scheme is more flexible for switching on/off and changing geometries.This work provides active and controllable components to thermal wave cloaks,which can be further used to design more active thermal wave metamaterials.

关键词： passive active thermal

active Balance Control of Humanoid Locomotion Based on Foot Position Compensation

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Journal of Bionic Engineering 2020年第1期17卷 134-147页

作者： Chengju Liu Tong Zhang Ming Liu Qijun Chen School of Electronics and Information Engineering Tongji UniversityShanghai 201804China School of Electronic and Computer Engineering Hong Kong University of Science and TechnologyHong Kong 999077China

A foot positioning compensator is developed in this paper for a full-body humanoid to retrieve its balance during continuous walking.An online Foot Position Compensator(FPC)is designed to improve the robustness of biped walking,which can modify predefined step position and step duration online with sensory feedback.Foot placement parameters are learned by the FPC based on the Policy Gradient Reinforcement Learning(PGRL)method.Moreover,the FPC assists the humanoid robot in rejecting external disturbances and recovering the walking position by re-planning the trajectories of walking pattern and the Center of Mass(CoM).An upper body pose control strategy is also presented to further enhance the performance of humanoid robots to overcome strong external disturbances.The advantages of this proposed method are that it neither requires prior information about the walking terrain conditions,nor relies on range sensor information for surface topology measurement.The effectiveness of the proposed method is verified via Webots simulation and real experiments on a full-body humanoid NAO robot.

关键词： humanoid walking active balance Foot Positioning Compensation(FPC) Policy Gradient Reinforcement Learning(PGRL)

Tube-based Model Reference Adaptive Control for Vibration Suppression of active Suspension Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 728-731页

作者： Yashar Mousavi Alireza Alfi Ibrahim Beklan Kucukdemiral Afef Fekih IEEE the Department of Applied Science School of ComputingEngineering and Built EnvironmentGlasgow Caledonian University the Faculty of Electrical Engineering Shahrood University of Technology the Electrical and Computer Engineering Department University of Louisiana at Lafayette

Dear editor,With the developments of industrial automation in recent years,vehicle suspension systems have received a great deal of attention in industry and academia due to their critical role in the chassis performance of vehicles[1].The suspension system is expected to guarantee the vehicle’s maneuverability and provide satisfactory ride comfort by absorbing the vibrations arising from the road surface excitations and ensuring road-holding capability and suspension safety.Motivated by the desirable performance of the model reference adaptive control(MRAC)approach,various literature studies have investigated its performance in diverse linear and nonlinear practical systems[2].

关键词： editor active guarantee

active steering control for vehicle rollover risk reduction based on slip angle estimation

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IET Cyber-Systems and Robotics 2020年第3期2卷 132-139页

作者： Ke Shao Jinchuan Zheng Bin Deng Kang Huang Han Zhao Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055People's Republic of China School of Software and Electrical Engineering Swinburne University of TechnologyHawthornVIC 3122Australia School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009People's Republic of China School of Mechanical Engineering Hefei University of TechnologyHefei 230009People's Republic of China

In this study,a robust controller is proposed for rollover risk suppression in automatically-driven vehicles by reducing the lateral acceleration through a steer-by-wire system equipped on the vehicles.First,since the slip angle is difficult to measure directly,a sliding mode observer combining an add-on switching term with a linear observer is developed to provide more robust estimation of slip angle in the presence of system uncertainties.Second,an adaptive sliding mode control method is proposed,in which the control gain is adaptively tuned to compensate for the system uncertainties.Lastly,simulation is conducted and the results verify that the proposed estimator and controller can reduce the vehicle rollover risk efficiently and robustly.

关键词： active estimation angle