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热镀锌沉没辊系转动失效机理及其影响因素研究 被引量:1
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作者 苗旺 钱胜 +3 位作者 李子正 张冀 王孝建 白振华 《轧钢》 北大核心 2025年第3期70-78,共9页
针对热镀锌机组沉没辊系(沉没辊、稳定辊、矫正辊)在锌锅内出现“轴端卡死”、“带钢打滑”等转动失效的问题,根据机组设备工艺特点和辊系受力情况,分析了辊系转动失效的机理;根据条元法、能量法和牛顿第二定律,确定了带钢单元临界打滑... 针对热镀锌机组沉没辊系(沉没辊、稳定辊、矫正辊)在锌锅内出现“轴端卡死”、“带钢打滑”等转动失效的问题,根据机组设备工艺特点和辊系受力情况,分析了辊系转动失效的机理;根据条元法、能量法和牛顿第二定律,确定了带钢单元临界打滑判断条件,并建立了辊系摩擦驱动力矩、外载荷合力、轴端摩擦阻力矩模型;在此基础上,构建了以转动动力因数为指标衡量沉没辊系转动能力的辊系转动失效临界判据模型。将该模型应用于某热镀锌机组,针对典型规格带钢的生产,分析了带钢张力、矫正辊插入量、刮刀刃辊面径向角度、刮刀力4种工艺参数对沉没辊系转动失效的影响。结果表明:增大带钢张力,对沉没辊转动能力有一定幅度的提升,但对稳定辊、矫正辊转动能力的影响不大;增大矫正辊插入量,沉没辊转动动力因数呈近线性递增,稳定辊转动动力因数先快速增加而后减小,矫正辊转动动力因数先增加而后缓慢递增,但矫正辊插入量增幅不宜大于5 mm;增大刮刀刃辊面径向角度,辊系各辊转动能力都有不同程度的提升;增大刮刀力,辊系各辊转动动力因数大幅减小,在过大的刮刀力设定下,稳定辊、矫正辊面临转动失效风险,实际生产中建议稳定辊、矫正辊、沉没辊的刮刀力分别小于15、300、800 N。 展开更多
关键词 热镀锌 沉没辊系 转动失效 临界判据模型 转动动力因数
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0Cr13Ni5Mo不锈钢表面化学镀Ni-P-Si工艺
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作者 李鹏 苗旺 +5 位作者 米佳鑫 郑嘉琪 任远达 景宗浩 杨雨云 王永东 《电镀与精饰》 北大核心 2025年第10期74-82,111,共10页
化学镀方法作为材料表面改性技术,可以提升材料表面的耐磨等性能。本文研究了镀液温度、pH和施镀时间对化学镀层组织和性能的影响。采用扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)观察镀层表面的微观形貌,分析镀层的成分变化并分析... 化学镀方法作为材料表面改性技术,可以提升材料表面的耐磨等性能。本文研究了镀液温度、pH和施镀时间对化学镀层组织和性能的影响。采用扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)观察镀层表面的微观形貌,分析镀层的成分变化并分析镀层的物相。对镀层进行了热处理,测试其显微硬度和耐磨性。结果表明:镀液温度为85℃、pH为5.5时,镀层表面光滑平整。施镀时间为60 min时,镀层厚度达到40μm,且呈现出良好的致密性,无明显的开裂缺陷。在最佳电镀参数,即镀液温度85℃、pH为5.5、施镀时间60 min以及热处理温度320℃、保温10 min条件下,镀层的显微硬度达1458.88 HV。 展开更多
关键词 化学镀 Ni-P-Si 显微硬度 耐磨性
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基于改进输出系数模型的驻马店市农业非点源污染负荷研究
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作者 高军侠 苗旺 +1 位作者 党宏斌 杨静静 《郑州航空工业管理学院学报》 2025年第5期103-112,共10页
为科学评估驻马店市农业非点源污染现状,利用改进输出系数模型,引入降雨、地形因子,基于地形、水文、社会经济、土地利用等数据,对该市各区县2021年农业非点源污染负荷进行估算。研究发现:驻马店市化学需氧量(COD)、氨氮(NH_(3)-N)、总... 为科学评估驻马店市农业非点源污染现状,利用改进输出系数模型,引入降雨、地形因子,基于地形、水文、社会经济、土地利用等数据,对该市各区县2021年农业非点源污染负荷进行估算。研究发现:驻马店市化学需氧量(COD)、氨氮(NH_(3)-N)、总氮(TN)和总磷(TP)的污染负荷总量分别为216695.332、2428.371、16160.514和2416.799 t·a^(-)1(吨/年)。各区县污染负荷差异较大,空间格局上大致具有中心驿城区最低,外圈各县自西平县起,污染负荷顺时针递增,直至泌阳县达顶值;内圈遂平县、汝南县顺时递增且小于外圈临近各县的分布特征。泌阳县污染负荷强度最高,驿城区最低,具有西南、东部两头高,且由中心驿城区向周边辐射递增的空间格局。污染物负荷强度高值区集中在泌阳县、确山县、平舆县和新蔡县。不同污染源对COD和NH3-N污染负荷的贡献率顺序为畜禽养殖>农村生活≈土地利用>渔业养殖;对TN和TP污染负荷的贡献率顺序为畜禽养殖>土地利用>农村生活>渔业养殖;除畜禽养殖外,农村生活和土地利用成为NH3-N污染的另外两大污染源;土地利用则成为TN和TP的另一重要污染源;渔业养殖对污染负荷的贡献率低于2%。规模化畜禽养殖是畜禽养殖污染源的重要途径,其贡献率占到畜禽养殖贡献率的60%以上。该研究结果可为驻马店市各区县农业非点源污染治理,以及提高水环境质量提供科学的决策依据。 展开更多
关键词 改进输出系数模型 农业非点源污染 污染负荷估算 驻马店市
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盐碱地水稻根际促生菌分离鉴定及其对盐胁迫下水稻促生效果研究 被引量:1
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作者 张洋 钱佳慧 +4 位作者 蒋继辉 李青 苗旺 王进军 胡建 《实验技术与管理》 北大核心 2025年第9期128-134,共7页
从盐碱地水稻根际土分离鉴定促生菌并研究其促生效果,为盐碱地水稻高效种植提供菌种资源。利用稀释平板法、培养基检测法、分子鉴定等技术分离鉴定根际促生菌,通过盆栽实验探究促生菌对盐胁迫下水稻生长的影响。经筛选获得3株根际促生菌... 从盐碱地水稻根际土分离鉴定促生菌并研究其促生效果,为盐碱地水稻高效种植提供菌种资源。利用稀释平板法、培养基检测法、分子鉴定等技术分离鉴定根际促生菌,通过盆栽实验探究促生菌对盐胁迫下水稻生长的影响。经筛选获得3株根际促生菌,分别鉴定为Pseudoclavibacter sp.、Providencia sp.和Planococcus sp.。盐胁迫下接种促生菌均能促进水稻生长、改善光合作用、提升植株脯氨酸含量和抗氧化酶活性、降低丙二醛含量。其中,Planococcus sp.表现出最高的促生潜力。研究通过综合性实验将微生物与现代农业发展需求有机结合,培养了学生利用微生物解决农业发展面临问题的能力,提升了学生在微生物应用领域的创新思维和实践能力。 展开更多
关键词 盐胁迫 水稻 根际促生菌 筛选 促生效果
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温度和pH对0Cr13Ni5Mo不锈钢表面化学镀Ni–P合金镀层组织及性能的影响 被引量:1
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作者 刘大庆 农海 +5 位作者 邓飞远 李鹏 苗旺 王金宇 杨雨云 王永东 《电镀与涂饰》 北大核心 2025年第6期42-46,共5页
[目的]在0Cr13Ni5Mo不锈钢表面化学镀Ni–P合金,以提高其硬度和耐磨性。[方法]研究了镀液温度和pH对化学镀Ni–P合金沉积速率,镀层宏观和微观形貌及显微硬度的影响。[结果]当温度为80℃、pH为4.2时,所得Ni–P合金镀层最均匀平整,表面胞... [目的]在0Cr13Ni5Mo不锈钢表面化学镀Ni–P合金,以提高其硬度和耐磨性。[方法]研究了镀液温度和pH对化学镀Ni–P合金沉积速率,镀层宏观和微观形貌及显微硬度的影响。[结果]当温度为80℃、pH为4.2时,所得Ni–P合金镀层最均匀平整,表面胞状结构排列紧密,呈非晶态结构,显微硬度高达824.10 HV。[结论]本研究可为水电装备关键部件表面强化提供参考,但后续应进一步研究Ni–P合金镀层在复杂工况下的长期服役性能及其耐蚀性。 展开更多
关键词 不锈钢 化学镀 镍−磷合金 微观组织 显微硬度
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回顾性分析单操作孔与传统多孔VATS肺结节切除术对SPN患者恢复进程及预后情况的影响 被引量:1
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作者 苏盼龙 苗旺 +5 位作者 刘方 韩永强 周硕果 李红秀 冀晓歌 贺兰天 《黑龙江医学》 2025年第7期790-792,共3页
目的:回顾性分析单操作孔与传统多孔电视胸腔镜手术(VATS)肺结节切除术治疗孤立性肺结节(SPN)患者的效果及对恢复进程、预后情况的影响。方法:回顾性分析2022年1月—2024年3月郑州市第三人民医院收治的100例SPN患者资料,按手术方案不同... 目的:回顾性分析单操作孔与传统多孔电视胸腔镜手术(VATS)肺结节切除术治疗孤立性肺结节(SPN)患者的效果及对恢复进程、预后情况的影响。方法:回顾性分析2022年1月—2024年3月郑州市第三人民医院收治的100例SPN患者资料,按手术方案不同分两组。以接受单操作孔VATS肺结节切除术治疗的50例患者列为A组,以接受传统多孔VATS肺结节切除术治疗的50例患者列为B组。对比两组患者手术及术后恢复指标,术前、术后1个月肺功能[一氧化碳弥散量(DLCO)、用力肺活量(FVC)、最大通气量(MVV)],术后1 d、3 d、7 d视觉模拟量表(VAS)评分,术前、术后3 d应激损伤指标[丙二醛(MDA)、P物质(SP)、超氧化物歧化酶(SOD)、C反应蛋白(CRP)]水平,并发症发生率。结果:B组首次下床活动、住院时间均长于A组,B组术中失血量及术后引流量均高于A组,差异均有统计学意义(t=9.051、13.153、10.712、18.479,P<0.001);术后1个月,A组DLCO、FVC、MVV水平高于B组,差异均有统计学意义(t=7.768、6.881、7.500,P<0.001);术后1 d、3 d、7 d,A组VAS评分均低于B组,差异均有统计学意义(t=7.832、8.318、13.373,P<0.001);术后3 d,A组血清MDA、SP、CRP水平较B组低,SOD较B组高,差异均有统计学意义(t=7.285、24.832、5.897、9.123,P<0.001);B组并发症发生率高于A组,差异有统计学意义(χ^(2)=5.005,P<0.05)。结论:相较于多孔VATS肺结节切除术治疗SPN患者,经单操作孔VATS肺结节切除术治疗SPN患者可减少并发症,且对机体产生的应激损伤更轻微,对肺功能影响更小。经单操作孔VATS肺结节切除术治疗更有助于降低术中失血量及术后引流量,缩短恢复进程,减轻术后疼痛感。 展开更多
关键词 孤立性肺结节 单操作孔 恢复进程 并发症 应激损伤 电视胸腔镜手术
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氢原子转移介导的烷烃C(sp^(3))—H选择性官能团化研究进展 被引量:1
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作者 王淼 黄雅豪 胡鹏 《有机化学》 北大核心 2025年第2期477-497,共21页
作为一种高度原子经济性和步骤经济性的策略,通过烷烃C(sp^(3))—H键的官能团化,直接将烷烃转化成附加值更高的化学品,一直备受关注.然而由于烷烃C(sp^(3))—H键广为人知的惰性,控制非活化C(sp^(3))—H键官能团化的化学选择性和区域选... 作为一种高度原子经济性和步骤经济性的策略,通过烷烃C(sp^(3))—H键的官能团化,直接将烷烃转化成附加值更高的化学品,一直备受关注.然而由于烷烃C(sp^(3))—H键广为人知的惰性,控制非活化C(sp^(3))—H键官能团化的化学选择性和区域选择性是一项重大的挑战.作为一种近期重新引起关注的方法,相比以往过渡金属催化,利用氢原子转移(HAT)实现C(sp^(3))—H键选择性官能团化有着其独特之处.在此,对最近兴起的各种HAT介导的非活化C(sp^(3))—H键官能团化的方法进行了分析,按照官能团化的选择性分类,重点介绍了目前实现区域选择性控制的方法.最后总结了目前方法的局限性,并对这一领域当前的挑战和未来的发展方向进行了展望. 展开更多
关键词 氢原子转移 非活化C(sp^(3))—H键 C(sp^(3))—H键官能团化 区域选择性 烷烃
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无服务边缘环境中的镜像缓存与资源分配 被引量:1
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作者 曾旺 池梦莉 +2 位作者 于正欣 苗旺 陈哲毅 《小型微型计算机系统》 北大核心 2025年第10期2515-2522,共8页
新兴的无服务边缘计算(Serverless Edge Computing,SEC)可在降低任务计算延迟的同时高效应对多变的服务模式,进而提升资源利用效率.然而,在资源受限的SEC中部署服务时常出现频繁的镜像置换,导致了过度的服务延迟与通信成本.现有的解决... 新兴的无服务边缘计算(Serverless Edge Computing,SEC)可在降低任务计算延迟的同时高效应对多变的服务模式,进而提升资源利用效率.然而,在资源受限的SEC中部署服务时常出现频繁的镜像置换,导致了过度的服务延迟与通信成本.现有的解决方案通常通过修改镜像结构或移动仓库位置来降低镜像请求时间,但其在一定程度上违背了容器隔离的设计初衷,并造成了额外的计算与存储开销.为了解决这些重要挑战,本文提出了一种新颖的面向SEC环境的镜像缓存与资源分配(Image Caching and Resource Allocation,ICRA)框架,并将原问题解耦为两个子问题分别进行求解.针对镜像缓存子问题,设计了一种基于改进深度强化学习(Deep Reinforcement Learning,DRL)的镜像缓存方法,通过引入双critic网络与延迟更新机制,以提升镜像缓存性能.针对资源分配子问题,根据任务属性与队列负载,引入凸优化理论进行容器资源分配以降低任务完成延迟.大量实验验证了所提ICRA框架的有效性.与基准方法相比,ICRA框架能够在保证服务质量的同时显著降低系统成本,并在不同场景下均表现出更加优越的性能. 展开更多
关键词 无服务边缘计算 镜像缓存 资源分配 深度强化学习 凸优化
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面向空天地一体化网络的切片划分与协作卸载
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作者 王鹏飞 郑霖睿 +2 位作者 于正欣 苗旺 陈哲毅 《小型微型计算机系统》 北大核心 2025年第9期2275-2282,共8页
新兴的空天地一体化网络(Space-Air-Ground Integrated Networks,SAGIN)赋予移动边缘计算(Mobile Edge Computing,MEC)更广泛的通信覆盖范围与更灵活的网络接入能力.然而,多样化的用户需求与低效的资源利用严重影响了SAGIN中计算卸载的... 新兴的空天地一体化网络(Space-Air-Ground Integrated Networks,SAGIN)赋予移动边缘计算(Mobile Edge Computing,MEC)更广泛的通信覆盖范围与更灵活的网络接入能力.然而,多样化的用户需求与低效的资源利用严重影响了SAGIN中计算卸载的服务质量(Quality-of-Service,QoS).现有研究工作大多针对静态环境或依赖系统先验知识,难以适应动态复杂的SAGIN环境.针对上述挑战,本文设计了一种新型的面向SAGIN的切片划分与协作卸载(Slice Partitioning and Collaborative Offloading,SPCO)框架.首先,提出了一种基于Transformer的切片资源划分方法,通过感知用户流量的变化趋势,实现高效的切片资源划分.接着,设计了一种基于改进深度强化学习(Deep Reinforcement Learning,DRL)的协作卸载与资源分配方法,通过应对Q值高估与高方差导致的难以收敛等问题,实现了通信和计算资源的合理分配以及异构平台的高效协作卸载.大量基于真实流量数据集的实验验证了SPCO的有效性.所提SPCO框架可有效增加服务商收益,且相较于其他基准方法可以取得更加优越的任务完成率与资源利用率. 展开更多
关键词 空天地一体化网络 网络切片 协作卸载 资源分配 深度强化学习
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面向遥感图像场景分类的特征对比域适应网络
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作者 苗旺 耿杰 +1 位作者 邓鑫洋 蒋雯 《指挥与控制学报》 北大核心 2025年第3期331-338,共8页
遥感图像场景分类能够提供实时的地表信息,对于复杂环境态势感知具有重要意义。遥感图像训练和测试数据通常来自不同分布,导致算法模型泛化性能差。针对场景分类任务中目标域与源域数据存在差异的问题,提出一种特征对比域适应网络,提取... 遥感图像场景分类能够提供实时的地表信息,对于复杂环境态势感知具有重要意义。遥感图像训练和测试数据通常来自不同分布,导致算法模型泛化性能差。针对场景分类任务中目标域与源域数据存在差异的问题,提出一种特征对比域适应网络,提取遥感图像域风格特征,构建域对比特征转换方法,实现遥感图像跨域场景分类。所提方法在公开遥感数据集上开展实验,较国际同类方法具有更优的性能。 展开更多
关键词 遥感图像场景分类 域适应 对比学习 深度学习
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Unveiling and swift diagnosing chronic wound healing with artificial intelligence assistance 被引量:1
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作者 Jiliang Deng Guoliang Shi +5 位作者 Zhihang Ye Quan Xiao Xiaoting Zhang Lei Ren Fangyu Yang miao wang 《Chinese Chemical Letters》 2025年第3期469-475,共7页
Histopathological analysis of chronic wounds is crucial for clinicians to accurately assess wound healing progress and detect potential malignancy.However,traditional pathological tissue sections require specific stai... Histopathological analysis of chronic wounds is crucial for clinicians to accurately assess wound healing progress and detect potential malignancy.However,traditional pathological tissue sections require specific staining procedures involving carcinogenic chemicals.This study proposes an interdisciplinary approach merging materials science,medicine,and artificial intelligence(AI)to develop a virtual staining technique and intelligent evaluation model based on deep learning for chronic wound tissue pathology.This innovation aims to enhance clinical diagnosis and treatment by offering personalized AI-driven therapeutic strategies.By establishing a mouse model of chronic wounds and using a series of hydrogel wound dressings,tissue pathology sections were periodically collected for manual staining and healing assessment.We focused on leveraging the pix2pix image translation framework within deep learning networks.Through CNN models implemented in Python using PyTorch,our study involves learning and feature extraction for region segmentation of pathological slides.Comparative analysis between virtual staining and manual staining results,along with healing diagnosis conclusions,aims to optimize AI models.Ultimately,this approach integrates new metrics such as image recognition,quantitative analysis,and digital diagnostics to formulate an intelligent wound assessment model,facilitating smart monitoring and personalized treatment of wounds.In blind evaluation by pathologists,minimal disparities were found between virtual and conventional histologically stained images of murine wound tissue.The evaluation used pathologists’average scores on real stained images as a benchmark.The scores for virtual stained images were 71.1%for cellular features,75.4%for tissue structures,and 77.8%for overall assessment.Metrics such as PSNR(20.265)and SSIM(0.634)demonstrated our algorithms’superior performance over existing networks.Eight pathological features such as epidermis,hair follicles,and granulation tissue can be accurately identified,and the images were found to be more faithful to the actual tissue feature distribution when compared to manually annotated data. 展开更多
关键词 Chronic wound Virtual pathological staining AI-assisted diagnostic and therapeutic Gel dressings
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基于嵌入对齐与参数激活的个性化联邦子图学习
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作者 卢恬英 钟璐英 +3 位作者 廖诗灵 于正欣 苗旺 陈哲毅 《模式识别与人工智能》 北大核心 2025年第5期425-441,共17页
融合子图学习与联邦学习后,联邦子图学习在保护数据隐私的同时可实现多客户端子图信息之间的协同学习.然而,由于不同客户端的数据收集方式存在差异,图数据通常呈现非独立同分布特性.同时,不同客户端局部图数据的结构和特征也存在较大差... 融合子图学习与联邦学习后,联邦子图学习在保护数据隐私的同时可实现多客户端子图信息之间的协同学习.然而,由于不同客户端的数据收集方式存在差异,图数据通常呈现非独立同分布特性.同时,不同客户端局部图数据的结构和特征也存在较大差异.这些因素导致联邦子图学习在训练过程中出现收敛困难和泛化能较差等问题.为了解决此问题,文中提出基于嵌入对齐与参数激活的个性化联邦子图学习方法(Personalized Federated Subgraph Learning with Embedding Alignment and Parameter Activation,FSL-EAPA).首先,根据客户端之间的相似性进行个性化模型聚合,降低数据非独立同分布对整体性能的影响.然后,引入参数选择性激活进行模型更新,应对子图结构特征的异质性.最后,利用更新后的客户端为各本地节点嵌入提供正负聚类表示,聚集同类局部节点.因此,FSL-EAPA能充分学习各节点的特征表示,较好地适应不同客户端之间的差异化数据分布.在真实基准图数据集上的实验表明FSL-EAPA的有效性,并且在不同场景下都能获得较高的分类精度. 展开更多
关键词 联邦子图学习 个性化模型聚合 参数选择性激活 节点嵌入对齐
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消融指数指导下高功率消融在老年心房颤动患者中的应用效果 被引量:7
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作者 苗旺 张楠 +1 位作者 郭敏 王睿 《中华老年心脑血管病杂志》 北大核心 2022年第2期151-154,共4页
目的探讨消融指数指导下高功率消融在老年心房颤动(房颤)患者中的有效性和安全性。方法选取2019年1月~2021年1月于山西医科大学第一医院行高功率(45 W)消融的老年房颤患者50例为高功率组,另选常规功率消融(35W)50例患者为常规功率组,2... 目的探讨消融指数指导下高功率消融在老年心房颤动(房颤)患者中的有效性和安全性。方法选取2019年1月~2021年1月于山西医科大学第一医院行高功率(45 W)消融的老年房颤患者50例为高功率组,另选常规功率消融(35W)50例患者为常规功率组,2组相同消融指数指导消融。消融终点为双侧肺静脉隔离,比较2组手术相关参数、并发症和手术成功率。结果高功率组中阵发性房颤比例明显高于常规功率组(76.0%vs 54.0%,P=0.021)。高功率组较常规功率组手术时间明显缩短,阵发性房颤为[(229.6±8.0)min vs(238.5±2.8)min,P=0.006],持续性房颤为[(237.5±12.8)min vs(263.0±22.8)min,P=0.024]。高功率组较常规功率组消融时间明显缩短,阵发性房颤为[(1384.4±78.3)s vs(1695.5±89.1)s,P=0.022],持续性房颤为[(1622.5±122.9)s vs(2037.0±437.9)s,P=0.045]。2组肺静脉隔离率均为100.0%。2组均未发生消融相关并发症,随访3个月时,高功率组与常规功率组的阵发性房颤患者和持续性房颤患者中房颤复发比例比较无显著差异(10.5%vs 11.1%,8.3%vs 13.0%,P>0.05)。结论在老年房颤患者中,高功率消融较常规功率消融明显缩短手术时间和消融时间,不增加手术并发症、不影响手术成功率。 展开更多
关键词 导管消融术 心房颤动 手术时间 认知障碍 手术后并发症
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Flow and Deposit Characteristics of Submerged Granular Column Collapse under Different Densities Ambient Fluids
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作者 miao wang Xinqiang Niu +2 位作者 Gang Ma Shumei Zhang Wei Zhou 《Journal of Earth Science》 2025年第6期2642-2657,共16页
The reservoir landslide is typically characterized by high-speed movement of a particle-fluid mixture,and its flow and deposit mechanisms are complex.This paper presents the mechanism of submerged granular column coll... The reservoir landslide is typically characterized by high-speed movement of a particle-fluid mixture,and its flow and deposit mechanisms are complex.This paper presents the mechanism of submerged granular column collapse under different densities ambient fluids based on coupled computational fluid dynamics and discrete element method(CFD-DEM)analysis.Important fluid-particle interaction forces,such as the drag force and the buoyancy,are considered by exchanging interaction forces between the CFD and DEM computations.We focus on the flow and deposit characteristics of submerged granular column collapse,namely the runout distance,the tail end height,the particle velocity,the energy,and deposit morphology,which are analyzed qualitatively and quantitatively.The change in fluid field caused by submerged granular column collapse and the formation of eddies are also discussed.A relatively dense fluid can significantly hinder the motion of granular flow,but can improve the conversion efficiency of kinetic energy from the vertical to the horizontal direction.Moreover,the eddies caused by fluid turbulence erode the surface of the granular pile,which is especially marked in a high-density fluid.The findings can provide vital theoretical support for the flow and deposit characteristics of granular flow under fluid and offer insights for the study of reservoir landslides. 展开更多
关键词 submerged granular column collapse different densities ambient fluids coupled CFD-DEM flow characteristics deposit morphology landslides hazards
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Unit coordination knowledge enhanced autonomous decision-making approach of heterogeneous UAV formation
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作者 Yuqian WU Haoran ZHOU +3 位作者 Ling PENG Tao YANG miao wang Guoqing wang 《Chinese Journal of Aeronautics》 2025年第2期381-402,共22页
Enhancing Autonomous Decision-Making (ADM) for unmanned combat aerial vehicle formations in beyond-visual-range air combat is pivotal for future battlefields, whereas the predominant reinforcement learning technique f... Enhancing Autonomous Decision-Making (ADM) for unmanned combat aerial vehicle formations in beyond-visual-range air combat is pivotal for future battlefields, whereas the predominant reinforcement learning technique for ADM has been proven to be inadequately fitting complex tactical Unit Coordination (UC), limiting the integrity of decision-making for formations. This study proposes a knowledge-enhanced ADM method, with a focus on UC, to elevate formation combat effectiveness. The main innovation is integrating data mining technique with tactical knowledge mining and integration. Foremost, based on Frequent Event Arrangement Mining (FEAM) theory, a cross-channel UC knowledge mining method is designed by introducing data flow, which is capable of capturing dynamic coordinative action sequences. Then, a dual-mode knowledge integration method is proposed by employing the Graph Attention Network (GAT) and attenuated structural similarity, bolstering the interplay between autonomous UC tactics fitting and knowledge injection. The experimental results demonstrate that the algorithm surpasses the existing methods, providing more strategic maneuver trajectories and a win rate of more than 90% in different scenarios. The method is promising to augment the autonomous operational capabilities of unmanned formations and drive the evolution of combat effectiveness. 展开更多
关键词 Unmanned aerial vehicle Autonomous decision making Autonomous agents Data mining Knowledge mining Reinforcement learning
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Phytoconstituent-derived nano-medicines/vesicles providing a promising dawn for inflammatory bowel disease
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作者 Linzhou Yin Xiaowen Jiang +5 位作者 miao wang Yiren Yang Zhonggui He Jin Sun Huiyuan Gao Mengchi Sun 《Chinese Chemical Letters》 2025年第6期31-47,共17页
Natural phytoconstituents exhibit distinct advantages in the management and prevention of inflammatory bowel disease(IBD),attributed to their robust biological activity,multi-target effects,and elevated safety profile... Natural phytoconstituents exhibit distinct advantages in the management and prevention of inflammatory bowel disease(IBD),attributed to their robust biological activity,multi-target effects,and elevated safety profile.Although promising,the clinical application of phytoconstituents have been impeded by poor water solubility,low oral bioavailability,and inadequate colonic targeting.Recent advancements in nanotechnology has offered prospective avenues for the application of phytoconstituents in the treatment of IBD.A common strategy involves encapsulating or conjugating phytoconstituents with nanocarriers to enhance their stability,prolong intestinal retention,and facilitate targeted delivery to colonic inflammatory tissues.Furthermore,drawing inspiration from the self-assembling nanostructures that emerge during the decoction process of Chinese herbs,a variety of natural active compounds-based nanoassemblies have been developed for the treatment of IBD.They exhibit high drug-loading capacities and surmount the challenges posed by poor water solubility and low bioavailability.Notably,phyto-derived nanovesicles,owing to their unique structure and biological functions,can serve as therapeutic agents or novel delivery vehicles for the treatment of IBD.Consequently,this review provides an extensive overview of emerging phytoconstituent-derived nano-medicines/vesicles for the treatment of IBD,intending to offer novel insights for the clinical management of IBD. 展开更多
关键词 Inflammatory bowel disease PHYTOCONSTITUENTS Nanotechnology NANOMEDICINES NANOASSEMBLIES NANOVESICLES
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The Relationship between Mobile Phone Dependency and Academic Burnout in Middle and High School Students
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作者 miao wang Meng lin Zhao +3 位作者 Dangyang Ma Xinyu Ji Donghe Li Zhansheng Xu 《International Journal of Mental Health Promotion》 2025年第8期1165-1180,共16页
Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examin... Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examines college populations,resulting in a lack of exploration on the internal mechanisms connecting mobile phone dependency to academic burnout.In addition to analysing the chain-mediated effects of sleep quality and cognitive flexibility,this study sought to provide theoretical insights for prevention by applying the Conservation of Resources theory to examine the relationship between academic burnout and mobile phone dependency among middle and high school students.Methods:A cluster convenience sampling approach was adopted.Data were collected from 811 middle and high school students in Tianjin,China,using a paper-based questionnaire battery comprising the Mobile Phone Addiction Index,the Pittsburgh Sleep Quality Index,the Cognitive Flexibility Scale,and the Adolescent Academic Burnout Scale.Descriptive statistics and correlation analyses were conducted using SPSS 25.0.Chain mediation effects were examined via the PROCESS macro,with significance assessed using bias-corrected bootstrap 95%confidence intervals.Results:A statistically significant positive link exists between mobile phone dependency and academic burnout among middle and high school students(r=0.575,p<0.001).Dependence on mobile phones had a substantial direct impact on academic burnout(β=0.303,p<0.001).Chain mediation analysis revealed that mobile phone dependency had a substantial direct impact on academic burnout(β=0.303,p<0.001).Sleep quality and cognitive flexibility mediated the link between mobile phone dependency and academic burnout.These indirect pathways represent 44.18%of the total effect.Conclusions:Mobile phone dependency contributes to academic burnout amongmiddle and high school students,mediated sequentially by sleep quality and cognitive flexibility.These findings suggest a potential intervention strategy to mitigate academic burnout by targeting excessive mobile phone use,enhancing sleep hygiene,and implementing cognitive flexibility training. 展开更多
关键词 Academic burnout cognitive flexibility mobile phone dependency student development sleep quality
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Comprehensive microbial and clinical profiling of functional constipation: A stratified comparative study of age and constipation subtype
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作者 Hui-Ting Zhu Hui-Fen wang +4 位作者 Qin Zhang Ju-Fang Bai miao wang Shi-Yu Du Yan-Li Zhang 《World Journal of Gastroenterology》 2025年第40期108-122,共15页
BACKGROUND Gut microbiota dysbiosis plays a central role in the pathogenesis of functional constipation(FC),but clinical treatment has shown uneven efficacy through methods of regulating intestinal flora.Most existing... BACKGROUND Gut microbiota dysbiosis plays a central role in the pathogenesis of functional constipation(FC),but clinical treatment has shown uneven efficacy through methods of regulating intestinal flora.Most existing studies have concentrated on overall case-control comparisons,with limited stratification by age or constipation subtype.Knowledge of how these factors shape gut microbiota composition remains inadequate,constraining the development of effective personalized microbiota-based interventions.Ninety-two patients with FC completed questionnaires and underwent anorectal manometry and gastrointestinal transit tests;stool samples were collected for 16S rRNA gene sequencing.Stool samples alone were collected from 34 healthy controls.Patients with FC were categorized into age groups(young,middle-aged,and older)and classified into normal-transit constipation,slow-transit consti-pation(STC),defecatory disorder(DD),and mixed constipation subtypes.Gut mi-crobial compositions across age groups and constipation subtypes were com-pared,and their correlations with clinical parameters were investigated.RESULTS The young group demonstrated significantly higher anal resting and squeeze pressures than the middle-aged and the older groups.Microbial richness and diversity were substantially lower in the older group than in middle-aged and young groups.Gut microbiota in the young group was predominantly enriched in taxa increasing sphincter tone and inhibiting intestinal peristalsis;the older group featured abundances of short-chain fatty acid-producing,beneficial taxa.The middle-aged group showed an enrichment of pro-inflammatory and pathogenic bacteria.Microbial richness and diversity were higher in STC than in the DD group.Moreover,STC group was enriched in taxa associated with slower peristalsis;DD group showed enrichment of motility-promoting taxa.CONCLUSION Significant differences in microbial composition and function were observed across age groups and constipation subtypes in FC,suggesting underlying pathophysiological heterogeneity and providing a basis for precision diagnosis and treatment. 展开更多
关键词 Gut microbiota Functional constipation Gastrointestinal disorder Microbial diversity Age-related differences
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Epidemic Evolution Trends and Spatiotemporal Clustering of Human Brucellosis in Xilingol League Inner Mongolia,from 2004 to 2023
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作者 Zhiguo Liu miao wang +3 位作者 Hao Tang Chuizhao Xue Zhenjun Li Canjun Zheng 《Biomedical and Environmental Sciences》 2025年第7期848-855,共8页
Objective Human brucellosis is a serious public health concern in the Xilingol League,Inner Mongolia;however,the epidemic trends are unclear.Method In this study,Joinpoint regression analysis and spatiotemporal analys... Objective Human brucellosis is a serious public health concern in the Xilingol League,Inner Mongolia;however,the epidemic trends are unclear.Method In this study,Joinpoint regression analysis and spatiotemporal analysis were applied to investigate the epidemic evolution of human brucellosis.Result From 2004 to 2023,a total of 35,747 cases were reported,with an annual average of 1787.35cases and an annual average incidence rate of 176.04/100,000.The incidence increased from 173.96/100,000 in 2004 to 500.71/100,000 in 2009 and fluctuated to 61.43/100,000 in 2023.Three epidemic join points were observed in which the disease experienced an alternative rise and fall,peaking in 2009(APC=21.73,P>0.001)and 2020(APC=21.51,P>0.001).The disease showed a persistent decline trend in lentitude(AAPC=–5.30,P>0.001),suggesting challenges in disease control and a higher risk of rebound.The most cases were reported in Xilinhot City(n=4,777),followed by 4,391 in Sonid Left Banner,and 4,324 in Abaga Banner.Spatiotemporal analysis revealed two high clusters(CI and CII)from 2005 to 2012,the high cluster encompassing eight counties and shifting from north to south.Conclusion The present analysis highlights that human brucellosis has decreased significantly in the Xilingol League,but the epidemic is still severe;further implementation of a strict control program is necessary. 展开更多
关键词 Human brucellosis EPIDEMIOLOGICAL Joinpoint regression analysis Spatiotemporal analysis
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Heat Transfer Characterization of TPMS Heat Exchangers Applied to the Aerospace Field
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作者 Nan Li miao wang +5 位作者 Jingwen Zhao Kechun Sun Cheng Bi Mu Du Ersheng You Mingyang Yang 《Frontiers in Heat and Mass Transfer》 2025年第2期601-614,共14页
In exploring hypersonic propulsion,precooler combined engines require the development of lightweight,efficient,and compact heat exchangers(HX).As additive manufacturing technology continues to progress,triply periodic... In exploring hypersonic propulsion,precooler combined engines require the development of lightweight,efficient,and compact heat exchangers(HX).As additive manufacturing technology continues to progress,triply periodic minimal surface(TPMS)structures,characterized by exceptionally high surface area to volume ratios and intricate geometric structures,have demonstrated superior heat transfer performance.This research examines the thermal-hydraulic(TH)behavior of FKS and Diamond as heat transfer structures under different Reynolds numbers through numerical simulations.The Nusselt number for FKS is 13.2%–17.6%higher than Diamond,while the friction factor for FKS is approximately 18.8%–29.3%higher.A detailed analysis of the internal flow mechanisms reveals that the flow pattern within TPMS can be summarized as cyclic convergence-separation-convergence.The fluid experiences constant disturbances from the structure in all spatial directions,generating strong turbulent mixing and large wall shear stresses,which significantly enhance heat transfer performance. 展开更多
关键词 TPMS heat transfer THERMAL-HYDRAULIC mathematical equation
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