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A real-time performance improvement method for composite time scale

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Chinese Physics B 2024年第9期33卷 350-357页

作者： Fangmin wang Wenlin Li Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo wang State Key Laboratory of Precision Space–time Information Sensing Technology Department of Precision InstrumentTsinghua UniversityBeijing 100084China Key Laboratory of Photonic Control Technology(Tsinghua University) Ministry of EducationBeijing 100084China Beijing Satellite Navigation Center Beijing 100094China

The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern *** improvement of CTS’s real-time performance will improve its stability,which strengths related applications’*** at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this *** determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is *** also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is *** results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial *** this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 *** experimental result proves that the CTS’s real-time performance is significantly improved.

关键词： composite time scale real-time performance calculation interval adjustment stage

Recent advances in organic cathodes for dual-ion batteries

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Science China Chemistry 2024年

作者： Wenli Hu Weisheng Zhang Chenxing Zhang Chengqiu Li Shilin Mei Changjiang yao School of Mechatronical Engineering State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of Technology

Dual-ion batteries(DIBs), a novel energy storage technology wherein both anions and cations actively participate in the electrochemical redox process, hold great promise for further cost reduction in chemical energy storage. Organic materials have garnered significant attention as cathode materials for DIBs due to high working voltage, exceptional rate capability, environmental friendliness, and unique designable structure. This review provides a detailed discussion of the energy storage mechanism and typical characteristics of organic cathode materials from various reaction active sites. This work also highlights the current limitations and proposes ideas for improvement. Finally, potential future directions for the advancement of DIBs are summarized.

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融合自适应注意力的多尺度火灾检测算法

北京理工大学学报 2024年第1期44卷 91-101页

作者：梁煜陈童张为天津大学微电子学院天津300072

针对实际场景下火灾检测准确度不高的现象,根据火灾自身特征提出了一种基于Anchor-free结构的火灾检测算法.将特征提取网络残差模块设计为多分支结构,并在其基础上嵌入根据火焰特征设计的自适应注意力模块,提取出更具表达力的火焰特征.... 详细信息

针对实际场景下火灾检测准确度不高的现象,根据火灾自身特征提出了一种基于Anchor-free结构的火灾检测算法.将特征提取网络残差模块设计为多分支结构,并在其基础上嵌入根据火焰特征设计的自适应注意力模块,提取出更具表达力的火焰特征.添加亚像素融合,利用高层特征丰富的通道信息增强多尺度特征的表达能力.设计特征增强模块强化最高层特征表示,更好地利用全局空间信息.引入自适应标签分配,强化网络对火焰特征的学习效果.利用改进后的GIoU Loss损失函数对边界框精细回归.该算法在自建数据集上的检测精度达到了94.9%,在公开数据集上也有较好的检测效果,且抗干扰能力强,适用于各种环境下的火灾检测,能够满足实际场景下火灾检测任务的需要.

关键词：深度学习火灾检测自适应注意力多尺度特征增强

Spontaneous hierarchical surface engineering of minerals through coupled dissolution-precipitation chemistry

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Aggregate 2024年第1期5卷 460-472页

作者： Jinyang Jiang Jiawen Zhang Lanxin wang Zeyu Lu Fengjuan wang Zhiyong Liu Hongbo Zeng Jiangsu Key Laboratory of Construction Materials School of Materials Science and EngineeringSoutheast UniversityNanjingChinal 2Chemical and Materials EngineeringUniversity of AlbertaEdmontonAlbertaCanada

Peculiar hierarchical microstructures in creatures inspire modern material design with distinct *** can effortlessly construct sophisticated yet long-range ordered microstructure across bio-membrane through ion secretion and ***,microstructure biomimicry in current technology generally requires elaborate,point-by-point ***,a spontaneous yet controllable strategy is developed to achieve surface microstructure engineering through a natural surface phenomenon similar to ion secretion-precipitation,that is,coupled dissolution-precipitation.A series of hierarchical microstructures on mineral surfaces in fluids with tunable morphology,orientation,dimension,and spatial distribution are achieved by simply controlling initial dissolution and fluid *** seawater,long-range ordered film of vertically aligned brucite flakes forms through interfacial dissolution,nucleation,and confinement-induced orientation of flakes with vertically grown{110}plane,on the edge of which,fusiform aragonite epitaxially *** negligible initial surface dissolution,prismatic aragonite epitaxially grows on a calcite polyhedron-packed *** tuning fluid chemistry,closely packed calcite polyhedron and loosely packed calcite micro-pillars are engineered through rapid and retarded precipitation,***,the spontaneously grown microstructures resemble those deliberately created by human or found in nature,and tremendously modulate surface *** findings open new possibilities for facile and customizable engineering of microstructural surfaces,hierarchical heterostructures,and biomimetic materials.

关键词： directional crystallization dissolution-precipitation chemistry hierarchical microstructures spontaneous growth surface engineering

基于LoRaWAN自适应数据速率的地下无线传感网络性能评估

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同济大学学报（自然科学版） 2024年第6期52卷 982-990页

作者：郝彤赵国政同济大学测绘与地理信息学院上海200092 同济大学空间信息科学与可持续发展应用中心上海200092

随着城镇化进程的不断加快和物联网技术的迅速进步,地下复杂土壤介质中的无线传感网络正成为新的研究热点。在此背景下,首先概述了基于LoRaWAN的地下无线传感网络基本架构和研究现状,接着搭建了网络仿真器并实现了自适应数据速率(ADR)... 详细信息

随着城镇化进程的不断加快和物联网技术的迅速进步,地下复杂土壤介质中的无线传感网络正成为新的研究热点。在此背景下,首先概述了基于LoRaWAN的地下无线传感网络基本架构和研究现状,接着搭建了网络仿真器并实现了自适应数据速率(ADR)调节机制在传感器节点端和网络服务端的2个优化算法,最后依据网络整体数据接收率和网络能耗等性能指标,分别从传感器节点的地下部署环境(土壤含水量和传感器埋藏深度)和LoRa物理层参数两方面进行了网络性能定量评估。结果表明,针对土壤这一复杂介质,ADR调节机制对LoRaWAN中的物理层参数具有较好的调节能力,该机制可为地下无线网络性能优化提供有利手段,有望大幅降低网络能耗。

关键词：地下无线传感网络物理层参数自适应数据速率(ADR)调节机制地下空间

Continual Reinforcement Learning for Intelligent AgriculturalManagement under Climate Changes

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Computers, Materials and Continua 2024年第1期81卷 1319-1336页

作者： wang, Zhaoan Jha, Kishlay Xiao, Shaoping Department of Mechanical Engineering Iowa Technology Institute University of Iowa Iowa City IA 52242 United States Department of Electrical and Computer Engineering University of Iowa Iowa City IA 52242 United States

Climate change poses significant challenges to agricultural management, particularly in adapting to extreme weather conditions that impact agricultural production. Existing works with traditional Reinforcement Learning (RL) methods often falter under such extreme conditions. To address this challenge, our study introduces a novel approach by integrating Continual Learning (CL) with RL to form Continual Reinforcement Learning (CRL), enhancing the adaptability of agricultural management strategies. Leveraging the Gym-DSSAT simulation environment, our research enables RL agents to learn optimal fertilization strategies based on variable weather conditions. By incorporating CL algorithms, such as Elastic Weight Consolidation (EWC), with established RL techniques like Deep Q-Networks (DQN), we developed a framework in which agents can learn and retain knowledge across diverse weather scenarios. The CRL approach was tested under climate variability to assess the robustness and adaptability of the induced policies, particularly under extreme weather events like severe droughts. Our results showed that continually learned policies exhibited superior adaptability and performance compared to optimal policies learned through the conventional RL methods, especially in challenging conditions of reduced rainfall and increased temperatures. This pioneering work, which combines CL with RL to generate adaptive policies for agricultural management, is expected to make significant advancements in precision agriculture in the era of climate change. © 2024 The Authors. Published by Tech Science Press.

关键词： Deep reinforcement learning

THE GLOBAL EXISTENCE AND ANALYTICITY OF A MILD SOLUTION TO THE 3D REGULARIZED MHD EQUATIONS

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Acta Mathematica Scientia 2024年第3期44卷 973-983页

作者：肖存涛邱华姚正安 School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou510090China Department of Mathematics South China Agricultural UniversityGuangzhou510642China School of Mathematics Sun Yat-sen UniversityGuangzhou510275China

In this paper,we study the three-dimensional regularized MHD equations with fractional Laplacians in the dissipative and diffusive *** establish the global existence of mild solutions to this system with small initial... 详细信息

关键词： regularized MHD equations fractional Laplacian global well-posedness analyticity decay rate

Isolation and characterization of mpox virus from the first mpox case in Shenzhen,China

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Virologica Sinica 2024年第2期39卷 335-337页

作者： Lin Cheng Liuqing Yang Miao wang Yabo Peng Haiyan wang Xiaoxiang Yang Juanjuan Zhao Mingxia Zhang Fuxiang wang Zheng Zhang Institute for Hepatology National Clinical Research Center for Infectious DiseaseShenzhen Third People's HospitalShenzhen518112China Department of Infectious Diseases Shenzhen Third People's HospitalShenzhen 518112China The Second Affiliated Hospital School of MedicineSouthern University of Science and TechnologyShenzhen 518112China

Dear Editor,Unlike previous outbreaks of the mpox(previously known as monkeypox),which were localized in Africa and resulted in small numbers of infections due to limited human-to-human transmission,the current outbreak beginning in May 2022,has spread rapidly primarily through human-to-human transmission in non-endemic countries(Gong et al.,2022).As of 27 Sep 2023,115 countries and regions have reported cases of mpox to the World Health Organization(WHO),bringing the total number of confirmed cases to 90,618 including 125 *** the number of new cases has decreased in most WHO regions in the second half of 2022,the curves reveal a long outbreak tail in different subregions of the *** worrying,106 mpox cases were reported in the mainland of China in June 2023.

关键词： mainland bringing

The Application Value of Swan-Neck Microcatheter in Peripheral Vascular Interventional Therapy

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Journal of Biosciences and Medicines 2024年第9期12卷 132-141页

作者： Xiang Zheng Ruidong Zhao yao Zhou Department of Interventional Medicine Zhuhai Peoples Hospital (Zhuhai Clinical Medical College of Jinan University) Zhuhai China

Background and Objectives: Establishing a stable pathway is the basis for interventional surgery, and hyper-selected intubation has become the basic requirement for vascular intervention therapy. Super-selection intubation can not only significantly improve the efficacy of peripheral intervention treatment, but also greatly reduce surgical complications. However, during the treatment of peripheral vascular intervention (such as liver tumor arterial chemotherapy embolism, hemoptysis bronchial arterial embolism, gastrointestinal hemorrhagic gastrointestinal arterial embolism, etc.), vascular mutation is often large, and there are many branches, and the direction of blood flow is into the direction of blood flow, the horns are even reverse, and even the use of straight-headed microstructures will have difficulty interpolation difficulties or even failure, which increases the risk of surgery and affects safety treatment. To overcome this, pre-plasticized microcatheters have emerged, among which the InstantPass Swan-Neck Microstructure is a catheter with a head-end morphology similar to Cobra. Our research aims to explore the feasibility, safety, and technical advantages of the use of swan-neck microcatheter in peripheral vascular hyperboloid intubation. Materials and Methods: From January 2023 to March 2024, 31 patients with swan-neck microstructure were used in the peripheral vascular intervention therapy outside the hospital. Among them, there were 23 men and 8 women, aged 32 - 81 years old, an average (55 ± 13) years, and the average irradiation time was 35.1 ± 24.7 minutes. 10 cases of iodide oil arterial chemotherapy embolism, 7 cases of microspheres of hepatic arteries, 3 cases of gastric duodenal artery selective embolism, 3 cases of vein embolism with esophageal stomach, and 2 cases of sperm varicose vein embolism, 2 cases of selective embolism of the intestinal membrane, 2 cases of uterine arteries embolism, and 2 cases of renal arterial embolism. 11 of these p

关键词： Peripheral Artery Superselective Catheterization Swan-Neck Microcatheter