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An epidemiological stochastic predator–prey model with prey refuge and harvesting
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作者 Israr Ali Hui Zhang +2 位作者 Syed Murad Ali Shah Abdulwasea Alkhazzan Yassine Sabbar 《Chinese Physics B》 2026年第2期342-356,共15页
Predator–prey interactions are fundamental to understanding ecosystem stability and biodiversity.In this study,we propose and analyze a stochastic predator–prey model that incorporates two critical ecological factor... Predator–prey interactions are fundamental to understanding ecosystem stability and biodiversity.In this study,we propose and analyze a stochastic predator–prey model that incorporates two critical ecological factors:prey refuge and harvesting.The model also integrates disease transmission within the predator population,adding an important layer of realism.Using rigorous mathematical techniques,we demonstrate the existence and uniqueness of a global positive solution,thereby confirming the model's biological feasibility.We further derive sufficient conditions for two key ecological scenarios:stochastic permanence,which ensures the sustained co-existence of prey and predators over time,and extinction,where one or both populations decline to zero.The interplay between prey refuge and harvesting is thoroughly examined to understand their combined impact on population dynamics.All theoretical results are validated by detailed numerical simulations,highlighting the applicability of the model to real-world ecological systems.From the simulation results,we observed that with an adequate level of prey refuge and predator harvesting,the susceptible predator and prey coexist with extensive oscillations,while the infected predator population was moving towards extinction.In addition,we have investigated the effect of disease transmission on system dynamics.Our results show that,as the transmission rate of disease increases,the susceptible predator approaches extinction,whereas,on the other hand,when it declines,the susceptible predator shows robust oscillations while the infected approaches extinction.In both cases,the prey population demonstrates robust stability due to the prey refuge.Our findings show that the management of harvesting and the prey refuge can be effective ecological tactics for disease control and species protection under stochastic environmental effects. 展开更多
关键词 stochastic predator–prey model HARVESTING prey refuge persistence extinction
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Research on Operation Strategies of Trade Publishing Knowledge Service Platform Based on the SICAS Model:A Case Study of CITIC Academy
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作者 WANG Jun ZHOU Xiaoyi 《Cultural and Religious Studies》 2026年第1期13-21,共9页
Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.... Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.To address this issue,this paper employs a combined approach of theoretical analysis and case study,introducing the SICAS(Sense-Interest-Connection-Action-Share)user consumption behavior analysis model and selecting“CITIC Academy”as the case study subject.It systematically examines and summarizes the platform’s operational practices and specific strategies,aiming to offer strategic insights and practical references for the operational improvement and sustainable,high-quality development of trade publishing knowledge service platforms. 展开更多
关键词 trade publishing knowledge service platform SICAS model operation strategy CITIC Academy
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基于Copernicus DEM 30的大尺度河道数字高程模型重构方法
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作者 李玉建 赵明成 +2 位作者 李琳 戴文鸿 安鹏 《长江科学院院报》 北大核心 2026年第2期201-210,共10页
为解决在大尺度河道数值模拟中河道遥感影像信息不全和实测地形高程资料部分缺失导致河道数字高程模型难以构建的问题,应用塔里木河阿拉尔—新渠满河段2011年相关水文资料与实测地形高程资料,通过ArcGIS软件结合Google Earth历史影像与C... 为解决在大尺度河道数值模拟中河道遥感影像信息不全和实测地形高程资料部分缺失导致河道数字高程模型难以构建的问题,应用塔里木河阿拉尔—新渠满河段2011年相关水文资料与实测地形高程资料,通过ArcGIS软件结合Google Earth历史影像与Copernicus DEM 30数据绘制河道临水线与外缘线,基于二次插值、平均差值法与局部加权回归算法,结合断面高程数据,完善河道地形高程。通过Mesh Generator组件,重构该河段的河道数字高程模型,并检验数据在MIKE 21水动力-泥沙模块数值模拟中的可行性。结果表明:通过模拟得到的流速、流量-水位关系及河道冲淤变化与实测资料对比,各项指标的误差均符合相关技术规程的允许偏差要求;平均差值法可以弥补主槽与河漫滩高程补衔接不自然的问题;局部加权回归算法能有效平滑河道主槽沿程断面高程数据。研究成果旨在丰富河道地形高程数据的重构方法,为解决大尺度河道DEM难以构建问题提供一种新思路。 展开更多
关键词 大尺度河道 数字高程模型(dem) Copernicus dem 30 塔里木河干流
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基于CFD-DEM的微阀射流疏堵模拟研究
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作者 魏列江 张海东 +3 位作者 魏小玲 刘豆豆 陈阳 强彦 《机床与液压》 北大核心 2026年第3期164-170,共7页
针对微阀在长期使用中因微小颗粒物沉积与黏附导致流道堵塞的问题,提出一种通过手指按压储液囊形成射流进行疏通的方法,清除堵塞物的同时避免损伤微阀结构。针对阀芯-阀座间颗粒团聚形成的堵塞,采用CFD-DEM耦合仿真方法,通过改变按压储... 针对微阀在长期使用中因微小颗粒物沉积与黏附导致流道堵塞的问题,提出一种通过手指按压储液囊形成射流进行疏通的方法,清除堵塞物的同时避免损伤微阀结构。针对阀芯-阀座间颗粒团聚形成的堵塞,采用CFD-DEM耦合仿真方法,通过改变按压储液囊时间,研究不同射流条件下颗粒聚集状态。仿真结果表明:当匀速按压时间为1.5 s时,射流速度增长平缓,只有20%的颗粒被冲刷出堵塞位置;按压时间为0.5 s时,射流速度迅速增大,97%的颗粒被冲刷掉,有效改善了微阀堵塞,按压时间显著影响疏堵效率。为进一步验证所提方法的有效性,使用放大样机进行实验验证。结果表明:按压1.5 s后,堵塞的明胶颗粒未能被完全冲刷,大量颗粒仍滞留于阀座区域;而按压时间缩短至0.5 s后,阀芯与阀座之间的明胶颗粒几乎完全被清除,微阀恢复正常工作状态。实验与仿真结果一致,证明基于CFD-DEM耦合仿真模拟按压储液囊射流冲刷堵塞物的方法可行。 展开更多
关键词 微阀 颗粒 堵塞 射流 CFD-dem
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半解析CFD-DEM耦合方法研究进展
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作者 许成顺 苏卓林 +1 位作者 徐佳琳 吴昕怡 《土木工程学报》 北大核心 2026年第2期1-19,共19页
流体-颗粒相互作用广泛存在于岩土工程、生物能源与工业过程等领域,CFD-DEM耦合方法因其能同时解析流体连续相与颗粒离散相的动态行为,已成为该类多相系统模拟的主流手段。文章系统综述了CFD-DEM耦合方法,重点聚焦于近年来快速发展的半... 流体-颗粒相互作用广泛存在于岩土工程、生物能源与工业过程等领域,CFD-DEM耦合方法因其能同时解析流体连续相与颗粒离散相的动态行为,已成为该类多相系统模拟的主流手段。文章系统综述了CFD-DEM耦合方法,重点聚焦于近年来快速发展的半解析策略。首先梳理了离散单元法在接触模型与非球形颗粒建模方面的进展;其次对比了全解析、非解析与半解析三类耦合方法的适用条件与技术特点;进而详细评述了基于统计核函数、扩散平滑、双网格及粒子点云等主流半解析算法的原理、优势与局限。最后,针对复杂颗粒形态处理、致密饱和体系模拟、多物理场耦合及机器学习融合等方面的挑战,提出未来研究方向。该文旨在为相关领域研究者提供方法选择与模型开发的参考依据,促进半解析CFD-DEM方法在岩土工程及相关领域的深入应用与发展。 展开更多
关键词 CFD-dem耦合 半解析方法 流体颗粒相互作用 孔隙场重构
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基于DEM-MFBD的煤矿机械疲劳失效机理与寿命优化研究
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作者 宋晓燕 李思齐 《机械管理开发》 2026年第2期159-160,163,共3页
针对煤矿机械长期运行于高负载、强冲击、潮湿高温等极端工况下易发生疲劳损伤的问题,评估煤矿机械在复杂工况下的疲劳寿命并提升其使用寿命。基于DEM-MFBD双向耦合方法,构建煤矿机械与散体物料仿真模型,模拟高负载、强冲击、湿热等极... 针对煤矿机械长期运行于高负载、强冲击、潮湿高温等极端工况下易发生疲劳损伤的问题,评估煤矿机械在复杂工况下的疲劳寿命并提升其使用寿命。基于DEM-MFBD双向耦合方法,构建煤矿机械与散体物料仿真模型,模拟高负载、强冲击、湿热等极端环境下的结构响应与动态应力演化,为煤矿机械疲劳寿命评估提供了思路,并为极端工况下关键部件的可靠性提升提供了可推广的路径。 展开更多
关键词 煤矿机械 疲劳评估 dem-MFBD耦合 疲劳失效机理
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基于SAR-DEM协同反演的洞庭湖芦苇湿地NPP分段函数回归模型与碳汇潜力评估
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作者 陈铸 李承昊 +5 位作者 李雄文 陈纪舟 邓锦峰 陈江平 高立 杨翊钧 《测绘通报》 北大核心 2026年第1期72-77,共6页
芦苇湿地是重要碳汇生态系统,准确评估其固碳能力对碳循环与生态安全具有重要意义。本文以洞庭湖芦苇湿地为例,提出了融合多源遥感的净初级生产力(NPP)估算方法,探讨物候变化对碳汇能力的驱动机制。采用分段函数回归,协同Sentinel-1 SAR... 芦苇湿地是重要碳汇生态系统,准确评估其固碳能力对碳循环与生态安全具有重要意义。本文以洞庭湖芦苇湿地为例,提出了融合多源遥感的净初级生产力(NPP)估算方法,探讨物候变化对碳汇能力的驱动机制。采用分段函数回归,协同Sentinel-1 SAR与DEM反演冠层高度,并融合Landsat 9 OLI与Sentinel-2光学数据,分别构建生长初期(4月)和枯萎期(11月)基于植被指数与冠层高度的NPP预测模型。研究显示,4月冠层高度与NPP显著正相关,11月枯萎期冠层高度维持但NPP显著下降且呈负相关;分段模型有效刻画了不同物候阶段的碳汇差异,并经2023年实测验证显著提高估算精度与可靠性。本文研究验证了多源遥感与分段建模可提升湿地碳汇动态监测的精度和时效性,为湿地精准管理提供了科学依据。 展开更多
关键词 芦苇湿地 碳汇核算模型 净初级生产力(NPP) SAR-dem协同反演 植被指数 分段函数回归模型
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直接求解热厚颗粒内传递和反应的生物质快速热解高精度CFD-DEM模拟
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作者 王櫆 任冠龙 +2 位作者 徐骥 葛蔚 熊勤钢 《工程热物理学报》 北大核心 2026年第2期512-520,共9页
热厚颗粒内传递和反应过程的精确建模是生物质快速热解计算流体力学(computational fluid dynamics,CFD)模拟的热点与难点。针对该问题,本工作构建了一种在球形颗粒内引入多壳层直接求解的传递和反应模型,耦合离散单元法(discrete eleme... 热厚颗粒内传递和反应过程的精确建模是生物质快速热解计算流体力学(computational fluid dynamics,CFD)模拟的热点与难点。针对该问题,本工作构建了一种在球形颗粒内引入多壳层直接求解的传递和反应模型,耦合离散单元法(discrete element method,DEM)实现了鼓泡流化床中生物质快速热解过程的高精度模拟。通过单个热厚生物质颗粒热解和实验室尺寸鼓泡床生物质快速热解实验数据验证了直接求解热厚颗粒内传递和反应模型的准确性,并探索了实验室尺度鼓泡床生物质快速热解的特性及操作条件的影响。结果表明,由于能够描述热厚颗粒内显著温度梯度导致的颗粒内径向热解程度的显著差异,本工作所提出的直接求解热厚颗粒内传递和反应模型能够显著提高生物质快速热解CFD-DEM模拟的精度。在操作条件对鼓泡床生物质快速热解的影响研究中发现,生物质颗粒热解的焦油产率随着温度升高先升后降,最佳热解温度在773 K;不同种类的生物质快速热解模拟结果表明焦油产率随纤维素成分的增加而略有增加,其中纯纤维素热解的焦油产率最高。 展开更多
关键词 生物质 快速热解 CFD-dem 热厚颗粒 流化床
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Dynamics of a Stochastic Epidemic Model with Age-group
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作者 LAN Xiaomin CHEN Guangmin +5 位作者 ZHOU Ruiyang ZHENG Kuicheng CAI Shaojian WEI Fengying JIN Zhen MAO Xuerong 《应用数学》 北大核心 2025年第1期294-307,共14页
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t... A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases. 展开更多
关键词 Epidemic model Age groups PERSISTENCE EXTINCTION
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基于DEMATEL-ISM的公立医院DRG绩效考核影响因素识别与探究
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作者 王莹 熊威 +1 位作者 高灿 李歆 《中国医院》 北大核心 2026年第3期34-38,共5页
目的:识别公立医院DRG绩效考核影响因素相互关联与作用机制,以推动公立医院高质量发展。方法:基于公立医院DRG绩效指标体系,应用DEMATEL方法获取影响矩阵并测算原因度、中心度等指标;结合ISM模型构建DRG绩效考核影响因素的递阶结构,进... 目的:识别公立医院DRG绩效考核影响因素相互关联与作用机制,以推动公立医院高质量发展。方法:基于公立医院DRG绩效指标体系,应用DEMATEL方法获取影响矩阵并测算原因度、中心度等指标;结合ISM模型构建DRG绩效考核影响因素的递阶结构,进而揭示因素之间的作用关系及影响机制。结果:CMI在DRG绩效考核中具有最高中心度;博士人员比例、论文专著数和市级以上课题数是主要驱动因素;患者满意度、低风险组死亡率是关键结果因素,依赖于其他因素。系统结构呈现5层递阶特征,即“人才驱动-技术支撑-持续运营-效率提升-质量安全改善”的传导路径。结论:人才建设是公立医院DRG绩效考核工作的根基,服务能力与效率是枢纽,患者体验与质量安全是目标,应完善人才培养机制,发展医疗新技术,提高专业能力,以提升服务效率与质量,增强患者就医幸福感。 展开更多
关键词 demATEL-ISM模型 公立医院 绩效考核 DRG 影响因素
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基于CFD-DEM耦合仿真的气吸式核桃定向摆放装置的设计与试验
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作者 刘梦迪 王应彪 +2 位作者 王周梅 张超宇 李九峰 《中国油脂》 北大核心 2026年第1期122-128,共7页
为确保核桃在吸附摆放过程中的姿态固定,设计一种气吸式核桃定向摆放装置。利用CFD-DEM气固两相耦合仿真方法对核桃定向摆放的工作过程进行分析,以核桃与吸口的距离、气流速度、负压强度为考察因素,定向合格指数为评价指标,采用单因素... 为确保核桃在吸附摆放过程中的姿态固定,设计一种气吸式核桃定向摆放装置。利用CFD-DEM气固两相耦合仿真方法对核桃定向摆放的工作过程进行分析,以核桃与吸口的距离、气流速度、负压强度为考察因素,定向合格指数为评价指标,采用单因素试验和响应面试验对核桃定向摆放装置的工作参数进行仿真优化,并结合实际试验验证定向吸附核桃的可行性。结果表明:核桃能被吸起的最低气流速度为25.5 m/s,最小负压强度为-93.6 kPa;影响定向合格指数的因素依次为气流速度、核桃与吸口的距离、负压强度;通过仿真优化和实际试验验证得到气吸式核桃定向摆放装置的最优工作参数为核桃与吸口的距离4 mm、气流速度27 m/s、负压强度-98 kPa,此时平均定向吸附成功率为95%。综上,气吸式核桃定向摆放装置满足核桃定向吸附摆放生产要求。 展开更多
关键词 核桃 气吸式 定向摆放 CFD-dem
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基于CFD-DEM耦合的碾米颗粒运动模拟与方法研究
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作者 杨勇 周龙 +2 位作者 范吉军 余南辉 李园 《食品与机械》 北大核心 2026年第1期64-71,共8页
[目的]针对卧式碾米机在碾米过程中造成颗粒破碎和过碾的问题,提出通过改变吸风气流方向提高糙米颗粒的碾磨质量。[方法]采用CFD-DEM耦合方法,分别对上吸风10 m/s、下吸风5 m/s和无风速3种状态进行数值仿真分析,并通过物理样机碾磨试验... [目的]针对卧式碾米机在碾米过程中造成颗粒破碎和过碾的问题,提出通过改变吸风气流方向提高糙米颗粒的碾磨质量。[方法]采用CFD-DEM耦合方法,分别对上吸风10 m/s、下吸风5 m/s和无风速3种状态进行数值仿真分析,并通过物理样机碾磨试验验证仿真结果。[结果]随着气流方向由上吸风转变到下吸风,颗粒沿Y轴的上升速度vy及三轴合成平均速度v整体降低,同层段位置处上吸风颗粒速度vy大于下吸风的,在碾白室中下部处明显观察到上吸风颗粒平均速度v大于下吸风颗粒的,碾磨区域内颗粒运动能力的差异导致容易过碾和破损区域的受力情况明显不同,颗粒运动能力强时碾白室底部颗粒受到的挤压力减小,颗粒运动能力弱时碾白室底部颗粒受到的挤压力增大;颗粒翻滚角速度在上吸风的作用下,对比无风速和下吸风效果增强;每种状态下3次的物理试验结果,上吸风10 m/s、无风速和下吸风5 m/s的碾磨度平均值分别为1.90%,2.20%,2.78%,破损率平均值分别为0.37%,0.46%,0.60%。[结论]上吸风状态下颗粒碾磨过程中的流动和受力特性优于无风速和下吸风的情况;上吸风比无风速和下吸风的碾磨度和破碎率明显下降。 展开更多
关键词 碾米颗粒 CFD-dem 颗粒流动 多孔介质模型
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基于CFD-DEM方法的高炉炉料轨迹落点预测
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作者 何潺 刘丕亮 +1 位作者 林帅辉 吴博 《冶金能源》 北大核心 2026年第1期62-69,共8页
针对当前高炉炉料落点预测的不足,文章采用CFD-DEM方法分析高炉炉料轨迹和落点位置,并利用程树森等提出的数学模型验证CFD-DEM模型的准确性。该方法全面考虑多种影响因素,包括科里奥利力、煤气流量、溜槽的旋转速度和倾角等,直观和精准... 针对当前高炉炉料落点预测的不足,文章采用CFD-DEM方法分析高炉炉料轨迹和落点位置,并利用程树森等提出的数学模型验证CFD-DEM模型的准确性。该方法全面考虑多种影响因素,包括科里奥利力、煤气流量、溜槽的旋转速度和倾角等,直观和精准地再现炉料在高炉内的运动过程。结果表明:当溜槽转速为1.05 rad/s时,科里奥利力对焦炭和矿石落点的影响分别达到28%和22%,煤气流非均匀性使焦炭和矿石的落点半径外移2.74%和3.87%。精准预测料流轨迹落点必须综合考虑科里奥利力和煤气流的影响。与数学模型对比,CFD-DEM模型对焦炭和矿石落点半径预测均方根误差分别为0.060 m和0.055 m,最大相对偏差不超过5%,与数学模型预测结果几乎一致,因此能够准确预测高炉炉料轨迹落点,为后续高炉布料操作提供新的理论依据。 展开更多
关键词 无料钟炉顶高炉 CFD-dem 数学模型验证 科里奥利力 气固耦合
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Mixed parking demand assignment in hub parking lots based on regression modeling 被引量:1
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作者 ZHANG Chu CHEN Kehan +1 位作者 CHEN Jun CHEN Jiayi 《Journal of Southeast University(English Edition)》 2025年第3期270-277,共8页
To adapt to the unique demand-supply features of accessory parking lots at passenger transport hubs,a mixed parking demand assignment method based on regression modeling is proposed.First,an optimal model aiming to mi... To adapt to the unique demand-supply features of accessory parking lots at passenger transport hubs,a mixed parking demand assignment method based on regression modeling is proposed.First,an optimal model aiming to minimize total time expenditure is constructed.It incorporates parking search time,walking time,and departure time,focusing on short-term parking features.Then,the information dimensions that the parking lot can obtain are evaluated,and three assignment strategies based on three types of regression models-linear regression(LR),extreme gradient boosting(XGBoost),and multilayer perceptron(MLP)-are proposed.A parking process simulation model is built using the traffic simulation package SUMO to facilitate data collection,model training,and case studies.Finally,the performance of the three strategies is com-pared,revealing that the XGBoost-based strategy performs the best in case parking lots,which reduces time expendi-ture by 29.3%and 37.2%,respectively,compared with the MLP-based strategy and LR-based strategy.This method offers diverse options for practical parking manage-ment. 展开更多
关键词 parking areas assignment hub parking lot regression-based modeling extreme gradient boosting(XG-Boost)
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基于DEM的南流江流域河网提取与流域特征分析
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作者 韦蔚来 覃睿 +1 位作者 刘惠雯 唐婕 《广西水利水电》 2026年第1期28-31,共4页
以南流江流域为例,利用ArcGIS软件构建数字高程模型,以不同的设置阈值计算得出的河网密度与实际河网密度对比,进而获得河网栅格最优的设置阈值,以此计算出南流江流域上4个水文站的流域参数。得出的流域面积误差不超过4%,干流长度误差在1... 以南流江流域为例,利用ArcGIS软件构建数字高程模型,以不同的设置阈值计算得出的河网密度与实际河网密度对比,进而获得河网栅格最优的设置阈值,以此计算出南流江流域上4个水文站的流域参数。得出的流域面积误差不超过4%,干流长度误差在11%~20%之间,河道比降误差为14.3%、29.7%。结果表明:提取高程模型时,设置最优河网栅格阈值使河网密度与实际值极为接近,但干流长及河道比降误差较多,这可能是DEM数据或ArcGIS算法的影响。南流江河网密度偏小,通过河道比降分析不同河段的洪灾特点,可为洪水预报、人员调度等提供依据。 展开更多
关键词 ARCGIS 数字高程模型(dem) 流域参数 南流江
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基于DEM数据的山东省大中型水库蓄水量估算
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作者 慎圆星 荆志铎 +2 位作者 王华昌 蔺文慧 赵金淼 《中国防汛抗旱》 2026年第2期36-41,共6页
以山东省大中型水库为研究对象,基于SRTM_30 m的数字高程模型(Digital Elevation Model,DEM)数据、大中型水库矢量数据和水库实测水位数据,利用地理信息系统软件三维分析功能,构建水库蓄水量估算模型,计算山东省2012—2020年年末大中型... 以山东省大中型水库为研究对象,基于SRTM_30 m的数字高程模型(Digital Elevation Model,DEM)数据、大中型水库矢量数据和水库实测水位数据,利用地理信息系统软件三维分析功能,构建水库蓄水量估算模型,计算山东省2012—2020年年末大中型水库的蓄水量,并与《山东省水资源公报》(以下简称水资源公报)公布的大中型水库蓄水量进行对比分析,根据分析结果调整模型参数。用此模型估算2021年12月山东省大中型水库的蓄水量,并利用水资源公报公布的数据做验证。结果表明,估算得出的水库蓄水量与水资源公报数据变化趋势一致,模型估算准确度较高,可用此方法估算某个时间节点的水库蓄水量。 展开更多
关键词 水库蓄水量 dem数据 遥感影像 水体提取 估算模型 山东省
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Revisiting the monocrotaline-treated rat as a model of inflammatory lung disease:COVID-19 and future pandemic threats?
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作者 Luke P.Kris Dani-Louise Dixon +1 位作者 Shailesh Bihari Jillian M.Carr 《Animal Models and Experimental Medicine》 2025年第10期1785-1793,共9页
The COVID-19 pandemic posed a challenge for clinical management of a new lung disease that was characterized by inflammation,endothelial cell dysfunction,and thrombosis,which occur after the replication phase of infec... The COVID-19 pandemic posed a challenge for clinical management of a new lung disease that was characterized by inflammation,endothelial cell dysfunction,and thrombosis,which occur after the replication phase of infection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).There are many laboratory models of active SARS-CoV-2 infection in mice,reflecting an acute lung injury in an otherwise healthy animal,but there is a lack of accurate animal models of the postviral inflammatory phase of the COVID-19 lung reflecting severe disease.The monocrotaline(MCT)-treated rat is a widely used laboratory model of pulmonary hypertension(PH).Not often discussed,however,are the observed changes in inflammation,edema,fibrosis,and microthrombosis in the lung prior to PH.At the cellular level,there is loss of pneumocytes and endotheliopathy,and at the molecular level the MCT rat lung is characterized by a proinflammatory cytokine profile,namely elevated interleukin 6,transforming growth factorβand tumor necrosis factor,M1 macrophage phenotype,and dysregulation of the angiotensin converting enzyme(ACE)/ACE2 balance.The systems-level pathophysiology of the MCT-treated rat includes progressive cardiopulmonary dysfunction.The MCT-treated rat clearly differs from the COVID-19 lung in terms of the triggers for pathology,but there are many parallels apparent in both the MCT-treated rat and the COVID-19 lung.The MCT-treated rat lung as a model of the COVID-19 lung may provide an in-depth understanding of the factors that drive the lung to more severe pathology,treatments that benefit lung recovery,or the factors that prove a useful research platform for future emerging respiratory threats of similar pathology. 展开更多
关键词 COVID-19 INFLAMMATION MONOCROTALINE rat model RESPIRATORY
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SPREADING SPEED FOR A TIME-SPACE PERIODIC EPIDEMIC MODEL IN DISCRETE MEDIA
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作者 Haiqin ZHAO 《Acta Mathematica Scientia》 2025年第3期1005-1018,共14页
This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward... This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward spreading speeds for the infective individuals, which can be used to estimate how fast the disease spreads. To overcome the difficulty arising from the lack of comparison principle for such time-space periodic nonmonotone systems, our proof is mainly based on constructing a series of scalar time-space periodic equations, establishing the spreading speeds for such auxiliary equations and using comparison methods. It may be the first work to study the spreading speed for time-space periodic non-monotone systems. 展开更多
关键词 spreading speed epidemic models time-space periodic habitats
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Spurious learning and bouncing back:Resilience and simulation modelling applied to the COVID-19 pandemic
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作者 Ashraf Labib 《Resilient Cities and Structures》 2025年第2期84-91,共8页
This paper aims to provide a window opportunity to share a reflection and learning from different countries and from other disciplines with the focus on resilience.There is also an attempt to theorize the concept of l... This paper aims to provide a window opportunity to share a reflection and learning from different countries and from other disciplines with the focus on resilience.There is also an attempt to theorize the concept of learning from spurious success and failure in the context of COVID-19.The main emphasis is to provide understanding of the causal factors and the identification of improved measures and modelling approaches to prevent and mitigate against future pandemics.Proposed decision tools of resilience and bowtie modelling as enablers for decision makers to prevent hazards and protect against their consequences. 展开更多
关键词 RESILIENCE COVID-19 Spurious learning GHS index Bowtie modelling
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Research on the Application Value of the Extended Nursing Intervention Model in Senile Dementia Patients
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作者 Fang Yu Xiaoxiao Wang 《Journal of Clinical and Nursing Research》 2025年第4期97-103,共7页
Objective:To explore the application value of the extended nursing intervention mode in senile dementia patients.Methods:A total of 60 cases of Alzheimer’s disease patients were selected as the research subjects and ... Objective:To explore the application value of the extended nursing intervention mode in senile dementia patients.Methods:A total of 60 cases of Alzheimer’s disease patients were selected as the research subjects and divided using the random number table method into the control group and the observation group,each with 30 cases.The control group adopted conventional nursing,while the observation group adopted the extended nursing model of this study.The self-care ability,quality of life,cognitive function,and the frequency of unsafe behaviors were compared between the two groups.Results:After 6 months of intervention,the results showed that the scores of all dimensions in the relevant data tables such as the activity of daily living(ADL)scale,simple intelligence scale,and health survey scale in the observation group were higher than those in the control group,and the differences were statistically significant(P<0.05).The incidence of unsafe behaviors in the observation group was lower than that in the control group,and the difference was statistically significant(χ^(2)=5.963,P<0.05).Conclusion:Extended nursing plays a positive role in the nursing of Alzheimer’s patients,including improving their cognitive function and restoring their self-care ability,so as to significantly improve their quality of life and reduce the occurrence of unsafe behaviors.It can be seen that the extended nursing intervention mode can be vigorously promoted in clinical practice. 展开更多
关键词 Senile dementia Extended nursing intervention model Coping style
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