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geographical Information Visualization on a Panoramic Sphere in an Immersive Environment

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Journal of Ocean University of China 2023年第4期22卷 961-974页

作者： MA Ying tian Fenglin liU Wen TANG Moran li Jinyu CHEN ge Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266100China Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China

In this paper,we propose a novel approach to visualizing global geographical information:a panoramic sphere in an immersive *** whole geographical surface can be observed through the rotating of heads as the viewpoint of the panoramic sphere is inside the *** compared three approaches to visualizing the earth for rendering the geographical information in a virtual reality *** the tasks of terrestrial and marine geographical information,we compare the visualization effects on a)a globe,b)a flat map and c)a panoramic *** geographical information tasks include the area comparison and direction *** geographical information tasks contain the visualization of sea surface temperature and sea surface *** terrestrial geographical information tasks,the experimental results show that the panoramic sphere outperforms the globe and the flat map,with a higher average accuracy and a shorter *** marine geographical information task,the panoramic sphere visualization is also superior to the flat map and the globe in an immersive environment for the sea surface temperature data and the sea surface current *** all three visualization experiments,the panoramic sphere is most preferred by the participants,particularly for global,transcontinental and transoceanic needs.

关键词： the panoramic sphere immersive environment virtual reality oceanographic information visualization

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改进TD3算法的机械臂三维路径规划方法

电光与控制 2025年第1期32卷 100-105页

作者：马天李超杨嘉怡西安科技大学计算机科学与技术学院西安710000

在军事航空领域中,复杂任务对机械臂路径规划提出了挑战。针对双延迟深度确定性策略梯度(TD3)算法学习效率低、样本利用率低的问题,提出了一种改进的TD3算法(Recurrent-TD3算法)。首先,将LSTM结合到策略网络与价值网络中,捕获航空控制... 详细信息

在军事航空领域中,复杂任务对机械臂路径规划提出了挑战。针对双延迟深度确定性策略梯度(TD3)算法学习效率低、样本利用率低的问题,提出了一种改进的TD3算法(Recurrent-TD3算法)。首先,将LSTM结合到策略网络与价值网络中,捕获航空控制任务中的时间序列信息,增强对时间序列变化的响应能力,使其能够在决策时考虑历史动作和状态,提高网络的表达能力;然后,将事后经验回放(HER)技术集成到TD3算法中,以解决任务中稀疏奖励难以学习的问题,通过将未达到目标的经验转化为达到新目标的经验,从而更有效地利用样本;最后,设计了一种基于包围盒的碰撞检测流程,以提高机械臂在军用航空任务中的安全性。实验表明,该算法相比于其他算法能够更快地找到一条无碰撞的路径,且平均路径长度最短。

关键词：机械臂路径规则 TD3 长短期记忆网络事后经验回放技术

Survey on the stability of networked control systems

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控制理论与应用（英文版） 2007年第4期5卷 374-379页

作者： Yuan ge li tian Zhenan liU Anhui Provincial Key Laboratory of Electric and Control Wuhu Anhui 241000 China Department of Automation University of Science and Technology of China Hefei Anhui 230027 China

The insertion of the communication network in the feedback control loop makes the analysis and design of a network control system more complex, and induces some issues that degrade the control system＇s performance and even cause system instability. The main aspects are focused on the stability analysis of Network Control Systems （NCSs） with network-induced delays, data packet dropouts, and multiple-packet transmission. These issues must be considered in the design of an NCS. This work summarizes the main research results, and remarks on some related handling approaches and techniques. The main purpose of the survey is to present the new research state of NCSs and to point out some fields of future work.

关键词： Networked control systems Network-induced delay Packet losses Multiple-packet transmission Stability

Effects of chlorine dioxide on morphology and ultrastructure of Fusarium sulphureum and its virulence to potato tubers

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International Journal of Agricultural and Biological Engineering 2017年第5期10卷 242-250页

作者： li Mei tian Shilong Shen Jin Wang Xizhuo Cheng Jianxin li Shouqiang ge Xia tian Jiachun Agricultural Product Storage and Processing Research Institute Gansu Academy of Agricultural SciencesLanzhou 730070China Chinese Academy of Agricultural Engineering Beijing 100125China

The inhibitory effect and its virulence of chlorine dioxide(ClO_(2))against dry rot of potato were *** were treated by ClO_(2),then observed for indoor bioassay,scanning electron microscopy(SEM)and transmission electron microscopy(TEM)were used to observe the morphology and ultrastructure of hyphae,and evaluated the control efficiency of ClO_(2) on potato tuber(LK99)dry rot by *** *** results showed that the pathogen of potato dry rot was sensitive to ClO_(2),the virulence of regression of y=5.05+7.308x,EC50 and EC90 were 0.3490 and 0.6261 respectively,the treatment of ClO_(2) could significantly inhibit the spore germination and mycelium growth of ***,which was in a concentration-dependent manner,SEM and TEM observed that the morphology and ultrastructure of *** hyphae were regularly damaged by ClO_(2),in vivo experiment further indicated that ClO_(2) could effectively control the dry rot of potato tubers with ***,and ClO_(2) at the concentration of 0.75 ug/mL could significantly reduce the incidence of potato tuber dry rot and lesion expansion *** study showed that ClO_(2) could greatly against the pathogen of ***,which could provide a scientific theoretical basis for the safe and efficient application of ClO_(2) in the prevention and control of potato diseases after harvest.

关键词： potato dry rot chlorine dioxide Fusarium sulphureum virulence morphology and ultrastructure

Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie Z.li Nagendran Ramalingam Shaomin li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

An investigation on micro pore structures and the vapor pressure mechanism of explosive spalling of RPC exposed to high temperature

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Science China(Technological Sciences) 2013年第2期56卷 458-470页

作者： JU Yang liU HongBin tian KaiPei liU JinHui WANG li ge ZhiShun State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology

Reactive powder concrete （RPC） is vulnerable to explosive spalling when exposed to high temperature. The characteristics of micro pore structure and vapor pressure of RPC are closely related to the thermal spalling. Applying mercury intrusion po- rosimetry （MIP） and scanning electron microscopy （SEM） techniques, the authors probed the characteristics of micro pore structures of plain RPC200 when heated from 20-350~C. The pore characteristics such as specific pore volume, threshold pore size and most probable pore size varying with temperatures were investigated. A vapor pressure kit was developed to measure the vapor pressure and its variation inside RPC200 at various temperatures. A thin-wall spherical pore model was proposed to ana- lyze the thermo-mechanical mechanism of spalling, by which the stresses varying with the vapor pressure q（T） and the character- istic size of wall （K） at any point of interest were determined. It is shown that the pore characteristics including specific pore volume, average pore size, threshold pore size and most probable pore size rise significantly with the increasing temperature. 200~C appears to be the threshold temperature above which the threshold pore size and the most probable pore size climb up dramatically. The increase in the specific pore volume results from the growth both in quantity and in volume of the transition pores and the capillary pores. The appearance of the explosive spalling in RPC200 is mainly attributed to being unable to form pathways in favor of releasing water steam in RPC and to thin-wall sphere domain where the vapor pressure governs the the rapid accumulation of high vapor pressures as well. The spalling is bounded through the pore model.

关键词： reactive powder concrete (RPC) high temperature spalling pore structure vapor pressure microstructures mercuryintrusion porosimetry (MIP)

GPU Accelerated Marine Data Visualization Method

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Journal of Ocean University of China 2014年第6期13卷 964-970页

作者： li Bo CHEN ge tian Fenglin SHAO Baomin JI Pengbo Department of Marine Technology Ocean University of ChinaEngineering Research Center of Marine Information TechnologyMinistry of Education Shandong Provincial Key Laboratory of Optical Astronomy and Solar Environment Institute of Space SciencesShandong University Institute of Oceanographic Instrumentation Shandong Academy of Science

The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean model and visualizing model results have become some of the most important research topics of ‘Digital Ocean'. In this paper, a spherical ray casting method is developed to improve the traditional ray-casting algorithm and to make efficient use of GPUs. Aiming at the ocean current data, a 3D view-dependent line integral convolution method is used, in which the spatial frequency is adapted according to the distance from a camera. The study is based on a 3D virtual reality and visualization engine, namely the VV-Ocean. Some interactive operations are also provided to highlight the interesting structures and the characteristics of volumetric data. Finally, the marine data gathered in the East China Sea are displayed and analyzed. The results show that the method meets the requirements of real-time and interactive rendering.

关键词： marine data visualization techniques and methodologies spherical ray casting line integral convolution multiquadric method VV-Ocean

High Efficiency and Anomalous Photoacoustic Behavior in Vertical CNTs Array

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Energy & Environmental Materials 2023年第1期6卷 105-110页

作者： Jiapu li Ziyu Wang Laiming Jiang Zechuan Yu Xu ge Jun Ouyang Xiaofei Yang Xiaobao tian He tian Benpeng Zhu School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Department of Mechanics Sichuan UniversityChengdu 610065China Institute of Microelectronics and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China

Miniaturized sound generators are attractive to realize intriguing *** device’s application is seriously limited due to the frequency-doubling *** address this issue,photoacoustic sound generator is considered as a promising ***,based on vertical single-wall carbon nanotubes(CNTs)array,we introduce a photoacoustic sound generator with internal nano-Helmholtz *** from traditional device that generates sound by periodically heating up the open space air around material,this sound generator produces an audio signal by forming a forced vibration of the air inside the ***,anomalous photoacoustic behavior is observed that the sound pressure level(SPL)curve has a resonance peak,the corresponding frequency of which is inversely proportional to the CNTs array’s ***,the energy conversion efficiency of this photoacoustic device is 1.64 times as large as that of a graphene sponge-based photoacoustic *** importantly,this device can be employed for music playing,bringing a new clew for the development of musical instruments in the future.

关键词： anomalous photoacoustic behavior CNTs array Nano-Helmholtz Cavity photoacoustic sound generator

Changes in the epidemiological burden of melanoma in China from 1990 to 2019 based on the Global Burden of Disease

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中华医学杂志(英文版) 2024年第21期137卷 2636页

作者： tian Qiong Hu li Bai Ruimin ge Rui Zhang Jian Department of Dermatology The First Affiliated Hospital of Xi’an Jiaotong University Xi’an Shaanxi China Department of Pathogenic Biology and Immunology School of Basic Medical Sciences Xi’an Jiaotong University Xi’an Shaanxi China

According to GBD 2019, in Asia, China ranked 12th, 15th, and 27th for these rates among 48 countries, and 3rd among East Asian countries [Supplementary Figure 1, http://***/CM9/C75].According to period and birth cohort trends of melanoma in China, the incidence ASR of melanoma in those aged ≥20 years tended to increase annually with age.[...]all data pertaining to incidence, prevalence, and mortality were estimates.[...]our results suggest that melanoma incidence in China increased during 1990–2019, with the burden of premature melanoma deaths on the socio-economic and healthcare systems in China surpassing the global average.

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