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基于A,Ф-A的变压器三维涡流场时域有限元POD降阶方法及其应用
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作者 朱章宸 刘尧 +1 位作者 刘刚 刘云鹏 《华北电力大学学报(自然科学版)》 北大核心 2025年第1期82-94,共13页
为解决三维涡流场时域求解时间长和存储空间需求较多的问题,首先基于A,Ф-A的三维涡流场时域有限元法结合POD(Proper Orthogonal Decomposition,POD)降阶算法实现了三维涡流场的高效计算。其次,以国际TEAM第21基准问题的模型B为例,通过... 为解决三维涡流场时域求解时间长和存储空间需求较多的问题,首先基于A,Ф-A的三维涡流场时域有限元法结合POD(Proper Orthogonal Decomposition,POD)降阶算法实现了三维涡流场的高效计算。其次,以国际TEAM第21基准问题的模型B为例,通过对比分析实测数据与自编程序和COMSOL的计算结果,验证了A,Ф-A的三维涡流场时域有限元求解方法的有效性。然后,通过POD不同阶数的降阶算例验证了POD降阶方法的有效性。最后,利用所提的基于A,Ф-A三维涡流场时域有限元法计算了一台三相变压器进行额定运行工况下的涡流场,并将计算结果与COMSOL仿真结果进行了对比。同时,还分析了三相变压器在负荷减少过程中的相电流和磁场变化,并分析了降阶模型阶数对计算时间和精度的影响,结果表明:15阶降阶模型耗时约为全阶耗时1/10,并且在方程降阶后各时间步的加速比最大,可达到70~165倍,在计算涡流损耗时相对误差不超过4.59%,计算精度相对较高。 展开更多
关键词 三维涡流场 三相变压器 A Ф-A方法 pod降阶方法
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茶树DREB基因的生信分析及其调控CsPOD3的抗旱机制
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作者 徐容 邓智英 +6 位作者 邵陈禹 罗玉麒 仇舒琪 王聪 周玲红 刘仲华 沈程文 《茶叶科学》 北大核心 2025年第1期29-42,共14页
基于课题组前期的转录组数据筛选到CsDREB11、CsDREB15和CsDREB25等基因。通过RT-qPCR验证,它们均受干旱诱导表达。从进化树、蛋白理化性质、亲/疏水性、二级和三级结构、亚细胞定位等方面进行预测与分析。结果表明,CsDREB11、CsDREB15... 基于课题组前期的转录组数据筛选到CsDREB11、CsDREB15和CsDREB25等基因。通过RT-qPCR验证,它们均受干旱诱导表达。从进化树、蛋白理化性质、亲/疏水性、二级和三级结构、亚细胞定位等方面进行预测与分析。结果表明,CsDREB11、CsDREB15和CsDREB25都与狭叶油茶(Camellialanceoleosa)的亲缘性最为密切,都属于不稳定的亲水性蛋白。二级/三级结构均以无规则卷曲和α-螺旋为主,其亚细胞定位均位于细胞核中。课题组前期的研究发现CsDREB25与CsPOD3均在干旱下高表达且呈显著相关,推测CsDREB25和CsPOD3存在相互作用关系。通过酵母单杂交验证(Y1H)和双荧光素酶报告基因检测(DLA)以及双荧光素酶互补成像(LCI)等方法试验验证了CsDREB25能正向调控CsPOD3的表达,提高POD的活性,清除过多活性氧,提高茶树的耐旱性。 展开更多
关键词 茶树 干旱胁迫 DREBs 过氧化物酶 生物信息学分析
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Pods Filling in Natural Pollination of 10 Spontaneous Cocoa Trees from French Guiana
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作者 Inago Caudou Trebissou Gnion Mathias Tahi Kacou Antoine Alban M’bo 《Agricultural Sciences》 2025年第1期193-205,共13页
The study focuses on the filling of pods from ten cacao clones originating from French Guiana in Côte d’Ivoire. Two reference clones (IFC5 and NA32) were used as controls. The parameters studied include the numb... The study focuses on the filling of pods from ten cacao clones originating from French Guiana in Côte d’Ivoire. Two reference clones (IFC5 and NA32) were used as controls. The parameters studied include the number of ovules per ovary, the average number of beans per pod, the fresh bean weight, and the pod index. The aim was to evaluate the genetic variability and agronomic performance of these clones under natural pollination conditions. The results show significant genetic variability between the clones for all traits studied. The IFC5 clone, known for its excellent pod filling, exhibited the highest apparent fertility (0.91), while the GU183/A clone had the lowest filling (0.47). Three types of distributions of the number of beans per pod were identified: a right-skewed unimodal distribution, characteristic of well-filled clones;a left-skewed unimodal distribution, associated with poorly filled clones;and an intermediate bimodal distribution. These differences could be related to pollination compatibility and the availability of compatible pollen. Regarding the fresh bean weight and pod index, the GU183/A clone stood out with the heaviest beans (3.27 g) but had a high pod index (49.58), indicating relatively low productivity. None of the Guyanese clones achieved the filling level of the IFC5 clone, although some surpassed the NA32 control. This study highlights the importance of apparent fertility and the number of beans per pod as essential criteria for cacao genetic improvement programs. The authors recommend extending research to a larger number of Guyanese clones and exploring complementary traits, such as the influence of pollination type and intergroup compatibility. 展开更多
关键词 Theobroma cacao PHYTOPHTHORA pod Index Apparent Fertility
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Analysis of Risk Factors for Delirium in Elderly Patients with Stanford-type B Aortic Dissection
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作者 Rong Wang Baoyi Yang +1 位作者 Na Wang Qi Tang 《Journal of Clinical and Nursing Research》 2025年第2期140-146,共7页
Objective:To investigate the incidence of delirium in elderly patients with Stanford-type B aortic dissection and analyze its risk factors.Methods:A convenience sample of 767 elderly patients with Stanford-type B aort... Objective:To investigate the incidence of delirium in elderly patients with Stanford-type B aortic dissection and analyze its risk factors.Methods:A convenience sample of 767 elderly patients with Stanford-type B aortic dissection admitted to the ICU from January 2020 to December 2023 was selected.Data were collected using a delirium-related questionnaire and the Confusion Assessment Method for the Intensive Care Unit(CAM-ICU).Results:The incidence of delirium in elderly Stanford B aortic dissection patients was 23.73%.Logistic regression analysis showed that gender,length of stay in the ICU,and duration of sedative drug use were independent risk factors for delirium in elderly patients(P<0.05).The model likelihood ratio test x^(2)=28.462,P<0.001;Hosmer-Lemeshow goodness-of-fit test x^(2)=0.715,P=0.878.Conclusion:The incidence of delirium in elderly patients with Stanford-type B aortic dissection is relatively low.Medical staff should conduct adequate and effective preoperative assessment according to the condition of elderly Stanford-type B aortic dissection patients,and use analgesic and sedative drugs reasonably to create a good treatment environment for patients,thereby minimizing the incidence of delirium in elderly patients with Stanford-type B aortic dissection as much as possible. 展开更多
关键词 ELDERLY Aortic dissection delirium Risk factors
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基于POD-αATS的油浸变压器瞬态温升降阶自适应变步长计算方法 被引量:3
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作者 刘刚 郝世缘 +2 位作者 胡万君 刘云鹏 李琳 《中国电机工程学报》 EI CSCD 北大核心 2024年第16期6656-6666,I0030,共12页
针对油浸式电力变压器瞬态温升计算效率过低的问题,该文提出本征正交分解-αATS(proper orthogonal decomposition-adaptive time stepping based onαfactor,POD-αATS)降阶自适应变步长瞬态计算方法。首先,推导变压器绕组瞬态温升计... 针对油浸式电力变压器瞬态温升计算效率过低的问题,该文提出本征正交分解-αATS(proper orthogonal decomposition-adaptive time stepping based onαfactor,POD-αATS)降阶自适应变步长瞬态计算方法。首先,推导变压器绕组瞬态温升计算的有限元离散方程;其次,采用POD降阶算法改善传统瞬态计算中存在的条件数过大及方程阶数过高的问题;同时对于瞬态计算中的时间步长选择问题,提出适用于非线性问题的αATS变步长策略;然后,为验证方法的有效性,基于110 kV油浸式电力变压器绕组的基本结构建立二维八分区数值计算模型,同时将计算结果与基于110 kV绕组的温升实验结果进行对比。数值计算及实验结果表明,所提算法与全阶定步长算法在流场和温度场中的精度几乎相同,且流场计算效率提升约45倍,温度场计算效率提升约38倍,计算速度得到显著提高。这一点在温升实验中同样得到验证,说明该文所提算法的准确性、高效性及一定的工程实用性。 展开更多
关键词 αATS变步长算法 本征正交分解降阶方法 瞬态流热耦合问题 快速计算方法 温升实验
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基于POD和Kriging的水滴收集量快速预测方法 被引量:1
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作者 郭琪磊 杜杰 张恒 《南京航空航天大学学报》 CAS CSCD 北大核心 2024年第2期318-326,共9页
数值模拟手段预测翼面处水滴撞击特性通常较为耗时,为快速准确计算结冰条件下的翼面处水滴收集量,提出了基于本征正交分解和代理模型的水滴收集量快速预测方法。首先对FAR 25部附录C中连续最大结冰条件进行优化拉丁超立方采样,通过数值... 数值模拟手段预测翼面处水滴撞击特性通常较为耗时,为快速准确计算结冰条件下的翼面处水滴收集量,提出了基于本征正交分解和代理模型的水滴收集量快速预测方法。首先对FAR 25部附录C中连续最大结冰条件进行优化拉丁超立方采样,通过数值模拟手段获得各采样点在翼面处水滴收集量分布,从而构造样本空间。在此基础上,利用本征正交分解(Proper orthogonal decompostion,POD)方法找到表达和重构水滴收集量的本征模态以及相应的拟合系数。最后,利用Kriging模型建立样本空间中各采样点与拟合系数间的代理模型,实现翼面处水滴收集量分布的快速预测。经多组工况验证表明:该方法可较为准确地预测翼面处水滴收集量分布,其计算成本较数值模拟方法大幅降低,能够为无人机防除冰设计提供有益参考。 展开更多
关键词 无人机 防/除冰 本征正交分解 代理模型 水滴收集量
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面向数字孪生模型应用的油浸式变压器绕组温度POD-RBFLP降阶计算方法 被引量:3
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作者 刘刚 胡万君 +4 位作者 郝世缘 高成龙 武卫革 刘云鹏 李琳 《中国电机工程学报》 EI CSCD 北大核心 2024年第11期4566-4578,I0034,共14页
了解油浸式电力变压器绕组的温度情况是保证其运行稳定性的关键,也是当前针对油浸式变压器数字孪生分析的必然需求。为了快速地获得变压器绕组的稳态温度,该文提出一种基于本征正交分解(proper orthogonal decomposition,POD)和包含线... 了解油浸式电力变压器绕组的温度情况是保证其运行稳定性的关键,也是当前针对油浸式变压器数字孪生分析的必然需求。为了快速地获得变压器绕组的稳态温度,该文提出一种基于本征正交分解(proper orthogonal decomposition,POD)和包含线性多项式的径向基函数响应面法(radial basis function response surface method including linear polynomial,RBFLP)的降阶计算模型。首先,讨论POD方法的降阶特性,并设计一种基于留一法交叉验证的自适应获得快照矩阵方法,以提高计算精度及效率;其次,采用响应面方法建立POD模态系数与绕组工况的相关关系,旨在实现通过绕组工况快速获得POD模态系数,从而跳过对降阶模型的复杂非线性计算,进而高效重构绕组温度场。相关算例表明,该方法具有较好的计算精度和效率,在50组测试工况下,与全阶计算相比,误差不超过2.5 K,且总计算时间仅为1.45 s;最后,基于110 kV变压器绕组搭建温升试验平台,试验结果表明,降阶计算结果相较于试验结果,平均计算误差不超过2 K,且单步计算时间仅为0.03 s,相较于同等规模的全阶计算,计算效率有较大幅度地提升。 展开更多
关键词 油浸式电力变压器 绕组稳态温度 本征正交分解 包含线性多项式的径向基函数响应面 降阶模型
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基于LSTM-POD的汽车湍流尾迹的高时间分辨速度场重构
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作者 杨志刚 李俣静 +2 位作者 夏超 王梦佳 余磊 《汽车工程》 EI CSCD 北大核心 2024年第7期1302-1313,共12页
本文针对方背Ahmed汽车标模的湍流尾迹,建立基于长短时记忆法(long short-term memory,LSTM)和本征正交分解(proper orthogonal decomposition, POD)相结合的深度学习模型LSTM-POD。通过建立非时间分辨平面速度场POD模态系数和若干离散... 本文针对方背Ahmed汽车标模的湍流尾迹,建立基于长短时记忆法(long short-term memory,LSTM)和本征正交分解(proper orthogonal decomposition, POD)相结合的深度学习模型LSTM-POD。通过建立非时间分辨平面速度场POD模态系数和若干离散点的时间分辨速度信号的映射关系,实现了方背Ahmed汽车标模湍流尾迹流场的高时间分辨率重构,并对比了不同时间步长配置,即单时间步长(LSTM-Sin)和多时间步长(LSTM-Mul)对重构效果的影响。研究表明:LSTM-POD模型在时间序列重构中具有较强的学习和泛化能力。另外,LSTM-Mul考虑到了时间上的连续性和相关性,相较于LSTM-Sin,其重构出的低阶模态系数和速度场与POD的重构结果更吻合。本研究提出的深度学习模型可以缓解通过实验及高精度数值模拟获取高时间分辨率流场数据资源消耗大、计算效率低等问题。 展开更多
关键词 汽车湍流尾迹 深度学习 流场重构 本征正交分解 长短时记忆法
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包含快照选择策略的POD-QDEIM油浸式变压器绕组瞬态温升降阶算法研究及其实验验证 被引量:1
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作者 刘刚 胡万君 +4 位作者 郝世缘 姜雄伟 高成龙 刘云鹏 王文浩 《中国电机工程学报》 EI CSCD 北大核心 2024年第12期4998-5010,I0033,共14页
为了提高采用有限元方法对油浸式电力变压器绕组瞬态温升进行仿真的计算速度,该文提出一种包含快照选择策略的本征正交分解(proper orthogonal decomposition,POD)-基于列主元QR分解的离散经验插值(QR factorization-discrete empirical... 为了提高采用有限元方法对油浸式电力变压器绕组瞬态温升进行仿真的计算速度,该文提出一种包含快照选择策略的本征正交分解(proper orthogonal decomposition,POD)-基于列主元QR分解的离散经验插值(QR factorization-discrete empirical interpolation method,Q-DEIM)(POD-QDEIM)算法。首先,文章基于最小二乘有限元法与迎风有限元法推导绕组流热耦合计算方程;其次,通过引入POD方法,降低有限元方程阶数提高求解效率;同时提出POD自适应快照选择策略,在保证降阶模型精度的前提下,减小快照矩阵规模;随后,为了改善POD方法求解非线性问题时效率不高的劣势,文章结合基于Q-DEIM方法,通过插值的方法形成方程中的非线性项,从而提高每一时步非线性项的形成效率;最后,基于110 kV油浸式电力变压器绕组基本结构,建立了八分区分匝绕组传热模型以及绕组温升试验装置对所提算法进行验证,仿真及实验结果表明POD-QDEIM降阶算法的计算精度在工程上属于可接受范围,其计算效率较全阶计算提升了近11.72倍,说明该算法在油浸式电力变压器绕组瞬态温升快速仿真领域的工程应用价值。 展开更多
关键词 绕组瞬态温升 快照选择策略 本征正交分解 离散经验插值 温升实验
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干旱胁迫对玉米幼苗ROS和POD的影响
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作者 王庆云 丁秀 《农业科技通讯》 2024年第3期80-82,共3页
山西省内市场上销售的玉米品种多为抗旱品种,为了更好地区分不同品种之间的差异,本研究选取8个玉米品种为试验材料,采用土培的方式,人工控制水量模拟干旱,研究干旱胁迫下不同品种玉米幼苗的活性氧(ROS)和过氧化物酶(POD)的变化。采用双... 山西省内市场上销售的玉米品种多为抗旱品种,为了更好地区分不同品种之间的差异,本研究选取8个玉米品种为试验材料,采用土培的方式,人工控制水量模拟干旱,研究干旱胁迫下不同品种玉米幼苗的活性氧(ROS)和过氧化物酶(POD)的变化。采用双抗体夹心法测定ROS的含量,采用愈创木酚法测定POD活性。结果表明,干旱胁迫下各品种玉米幼苗ROS含量全部上升,其中大丰26、大丰30和并单16的ROS含量增加不显著,其余品种增加显著;干旱胁迫诱导大丰26和大丰30的POD活性显著上升,其余品种的POD活性变化不显著。分析ROS和POD活性指标变化可以看出,与其余7个品种相比,大丰30的抗旱能力更强。 展开更多
关键词 玉米幼苗 干旱胁迫 pod ROS
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基于POD方法的EPR燃料棒流致振动特性分析 被引量:2
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作者 闵光云 冯琳娜 姜乃斌 《力学学报》 EI CAS CSCD 北大核心 2024年第3期659-669,共11页
EPR(European pressurized reactor)燃料棒相比M310燃料棒的棒长更长,导致其频率降低、幅值增大,在冷却剂的作用下,会加剧格架与棒束之间微动磨损(grid-to-rod fretting,GTRF),进而造成放射性物质的泄漏.将EPR燃料棒简化为3D梁模型,将... EPR(European pressurized reactor)燃料棒相比M310燃料棒的棒长更长,导致其频率降低、幅值增大,在冷却剂的作用下,会加剧格架与棒束之间微动磨损(grid-to-rod fretting,GTRF),进而造成放射性物质的泄漏.将EPR燃料棒简化为3D梁模型,将刚凸和弹簧对燃料棒的约束等效为弹性约束,将带格架的燃料棒简化为多跨连续简支梁模型,然后基于ANSYS-APDL建立了EPR燃料棒的有限元模型.阐述了湿模态分析和湍流激振响应分析的基本原理,整理了12个格架失效工况,系统地研究了格架失效对湿模态和湍流激振响应的影响.针对EPR燃料棒流致振动问题,提出了采用本征正交分解(proper orthogonal decomposition,POD)原理分析EPR燃料棒流致振动特性的方法,通过对快照矩阵进行POD分解生成投影子空间,将湍流激振响应投影到子空间进行模型降阶,最后在物理空间快速地重构湍流激振响应.结果表明:格架失效会导致频率降低,且湍流激振响应的幅值会在格架失效处增大;当格架失效使得EPR燃料棒模型成为悬臂梁结构时,湍流激振响应最大;前2阶POD降阶模型基本能快速重构燃料棒的湍流激振响应,且误差非常小.文章的研究将有助于核反应堆工程的优化和设计. 展开更多
关键词 流致振动 pod方法 EPR燃料棒 模态分析 格架失效
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Gappy POD算法重构储能电池组核心温度及与BP神经网络预测能力对比 被引量:2
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作者 苑清扬 薛珂 +1 位作者 张博 兰天 《工程科学学报》 EI CSCD 北大核心 2024年第1期166-177,共12页
储能电池组中电池核心温度的实时监控对于防控电池热失控有着重要的意义.为克服工业实际中电池组内部无法布置多温度测点导致的温度数据获取不全面等问题,本文将Gappy POD重构算法引入储能电池核心温度实时监控问题中,通过监测电池组表... 储能电池组中电池核心温度的实时监控对于防控电池热失控有着重要的意义.为克服工业实际中电池组内部无法布置多温度测点导致的温度数据获取不全面等问题,本文将Gappy POD重构算法引入储能电池核心温度实时监控问题中,通过监测电池组表面温度预测内部核心温度.通过搭建简化的拟储能电池实验台模拟电池温升,测试了Gappy POD算法在工况平稳变化和工况剧烈变化条件下的稳定性和对核心温度的实时重构能力;对比了Gappy POD算法的重构能力和BP神经网络(Back propagation neural network)的预测能力,并探究了Gappy POD算法和BP神经网络在不同大小的数据库训练条件下的重构预测能力.研究表明,Gappy POD重构算法具有高预测精度、稳定性强并且对数据库数据量依赖性低等优势,为算法在储能电池热管理中的实际应用提供了基础. 展开更多
关键词 Gappy pod BP神经网络 储能电池 热管理 核心温度预测
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Predictive modeling for postoperative delirium in elderly patients with abdominal malignancies using synthetic minority oversampling technique 被引量:3
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作者 Wen-Jing Hu Gang Bai +6 位作者 Yan Wang Dong-Mei Hong Jin-Hua Jiang Jia-Xun Li Yin Hua Xin-Yu Wang Ying Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1227-1235,共9页
BACKGROUND Postoperative delirium,particularly prevalent in elderly patients after abdominal cancer surgery,presents significant challenges in clinical management.AIM To develop a synthetic minority oversampling techn... BACKGROUND Postoperative delirium,particularly prevalent in elderly patients after abdominal cancer surgery,presents significant challenges in clinical management.AIM To develop a synthetic minority oversampling technique(SMOTE)-based model for predicting postoperative delirium in elderly abdominal cancer patients.METHODS In this retrospective cohort study,we analyzed data from 611 elderly patients who underwent abdominal malignant tumor surgery at our hospital between September 2020 and October 2022.The incidence of postoperative delirium was recorded for 7 d post-surgery.Patients were divided into delirium and non-delirium groups based on the occurrence of postoperative delirium or not.A multivariate logistic regression model was used to identify risk factors and develop a predictive model for postoperative delirium.The SMOTE technique was applied to enhance the model by oversampling the delirium cases.The model’s predictive accuracy was then validated.RESULTS In our study involving 611 elderly patients with abdominal malignant tumors,multivariate logistic regression analysis identified significant risk factors for postoperative delirium.These included the Charlson comorbidity index,American Society of Anesthesiologists classification,history of cerebrovascular disease,surgical duration,perioperative blood transfusion,and postoperative pain score.The incidence rate of postoperative delirium in our study was 22.91%.The original predictive model(P1)exhibited an area under the receiver operating characteristic curve of 0.862.In comparison,the SMOTE-based logistic early warning model(P2),which utilized the SMOTE oversampling algorithm,showed a slightly lower but comparable area under the curve of 0.856,suggesting no significant difference in performance between the two predictive approaches.CONCLUSION This study confirms that the SMOTE-enhanced predictive model for postoperative delirium in elderly abdominal tumor patients shows performance equivalent to that of traditional methods,effectively addressing data imbalance. 展开更多
关键词 Elderly patients Abdominal cancer Postoperative delirium Synthetic minority oversampling technique Predictive modeling Surgical outcomes
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Metabolomic Analysis in Saliva and Different Brain Regions of Older Mice with Postoperative Delirium Behaviors
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作者 LIU Xiao CAO Ying +3 位作者 LIN Xiao Wan GAO Dan Yang MIAO Hui Hui LI Tian Zuo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第2期133-145,共13页
Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ages.However,the underlying mechanism is yet unknown.Our study aimed to e... Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ages.However,the underlying mechanism is yet unknown.Our study aimed to explore the changes in metabolites in three specific brain regions and saliva of older mice with postoperative delirium behavior and to identify potential non-invasive biomarkers.Methods Eighteen-month-old male C57/BL6 mice were randomly assigned to the anesthesia/surgery or control group.Behavioral tests were conducted 24 h before surgery and 6,9,and 24 h after surgery.Complement C3(C3)and S100 calcium-binding protein B protein(S100beta)levels were measured in the hippocampus,and a metabolomics analysis was performed on saliva,hippocampus,cortex,and amygdala samples.Results In total,43,33,38,and 14 differential metabolites were detected in the saliva,hippocampus,cortex,and amygdala,respectively.“Pyruvate”“alpha-linolenic acid”and“2-oleoyl-1-palmitoy-snglycero-3-phosphocholine”are enriched in one common pathway and may be potential non-invasive biomarkers for POD.Common changes were observed in the three brain regions,with the upregulation of 1-methylhistidine and downregulation of D-glutamine.Conclusion Dysfunctions in energy metabolism,oxidative stress,and neurotransmitter dysregulation are implicated in the development of POD.The identification of changes in the level of salivary metabolite biomarkers could aid in the development of noninvasive diagnostic methods for POD. 展开更多
关键词 METABOLOMIC Postoperative delirium(pod) Mechanism Biological marker
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Nurse anesthetists’perceptions and experiences of managing emergence delirium:A qualitative study 被引量:1
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作者 Yi Xin Fu-Cai Lin +5 位作者 Chen Huang Bin He Ya-Ling Yan Shuo Wang Guang-Ming Zhang Rui Li 《World Journal of Psychiatry》 SCIE 2024年第4期553-562,共10页
BACKGROUND This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium(ED),a common and complex postoperative complication in the post... BACKGROUND This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium(ED),a common and complex postoperative complication in the post-anesthesia care unit.The role of nurses in managing ED is critical,yet research on their understanding and management strategies for ED is lacking.AIM To investigate anesthetic nurses’cognition and management experiences of ED in hopes of developing a standardized management protocol.METHODS This study employed a descriptive phenomenological approach from qualitative research methodologies.Purposeful sampling was utilized to select 12 anesthetic nurses from a tertiary hospital in Shanghai as research subjects.Semi-structured interviews were conducted,and the data were organized and analyzed using Colaizzi’s seven-step analysis method,from which the final themes were extracted.RESULTS After analyzing the interview content,four main themes and eight subthemes were distilled:Inefficient cognition hinders the identification of ED(conceptual ambiguity,empirical identification),managing diversity and challenges(patientcentered safe care,low level of medical-nursing collaboration),work responsibilities and pressure coexist(heavy work responsibilities,occupational risks and stress),demand for high-quality management(expecting the construction of predictive assessment tools and prevention strategies,and pursuing standardized management processes to enhance management effectiveness).CONCLUSION Nursing managers should prioritize the needs and suggestions of nurses in order to enhance their nursing capabilities and provide guidance for standardized management processes. 展开更多
关键词 Anesthetic nurse Emergence delirium Postoperative complications COGNITION Disease management Qualitative research
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High-risk factors for delirium in severely ill patients and the application of emotional nursing combined with pain nursing 被引量:1
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作者 Hong-Ru Li Yu Guo 《World Journal of Psychiatry》 SCIE 2024年第7期1027-1033,共7页
BACKGROUND Delirium is a neuropsychiatric syndrome characterized by acute disturbances of consciousness with rapid onset,rapid progression,obvious fluctuations,and preventable,reversible,and other characteristics.Pati... BACKGROUND Delirium is a neuropsychiatric syndrome characterized by acute disturbances of consciousness with rapid onset,rapid progression,obvious fluctuations,and preventable,reversible,and other characteristics.Patients with delirium in the intensive care unit(ICU)are often missed or misdiagnosed and do not receive adequate attention.AIM To analyze the risk factors for delirium in ICU patients and explore the applica-tion of emotional nursing with pain nursing in the management of delirium.METHODS General data of 301 critically ill patients were retrospectively collected,including histories(cardiovascular and cerebrovascular diseases,hypertension,smoking,alcoholism,and diabetes),age,sex,diagnosis,whether surgery was performed,and patient origin(emergency/clinic).Additionally,the duration of sedation,Richmond Agitation Sedation Scale score,combined emotional and pain care,ven-tilator use duration,vasoactive drug use,drainage tube retention,ICU stay du-ration,C-reactive protein,procalcitonin,white blood cell count,body tempe-rature,Acute Physiology and Chronic Health Evaluation II(APACHE II)score,and Sequential Organ Failure Assessment score were recorded within 24 h after ICU admission.Patients were assessed for delirium according to confusion assessment method for the ICU,and univariate and multivariate logistic regre-ssion analyses were performed to identify the risk factors for delirium in the patients.RESULTS Univariate logistic regression analysis was performed on the 24 potential risk factors associated with delirium in ICU patients.The results showed that 16 risk factors were closely related to delirium,including combined emotional and pain care,history of diabetes,and patient origin.Multivariate logistic regression analysis revealed that no combined emotional and pain care,history of diabetes,emergency source,surgery,long stay in the ICU,smoking history,and high APACHE II score were independent risk factors for de-lirium in ICU patients.CONCLUSION Patients with diabetes and/or smoking history,postoperative patients,patients with a high APACHE II score,and those with emergency ICU admission need emotional and pain care,flexible visiting modes,and early intervention to reduce delirium incidence. 展开更多
关键词 Critical illness delirium Risk factor Intensive care unit Emotional nursing Pain nursing
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POD和DMD方法对燃料棒流致振动特性的分析
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作者 闵光云 姜乃斌 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第10期2162-2172,共11页
燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响... 燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响应数据库。该数据库采用不同支撑刚度值来模拟和检查燃料棒可能遇到的情况。基于数据库组装快照矩阵,采用两种数据驱动方法(POD方法和DMD方法)搭建了1个高保真降阶模型(ROM),该ROM能够实现流致振动响应的快速重构。对比了POD方法和DMD方法重构燃料棒流致振动响应的效果以及各自的优点和缺点。研究发现:使用相同数量的模态重构燃料棒的流致振动响应时,POD方法的重构效果优于DMD方法;基于相同数量的模态重构时,刚度为1 N/mm的重构效果最差,这主要是因为刚度越小,频率越小,系统的振幅越大,需要更多数量的模态才能捕捉大幅振动带来的影响;DMD方法不仅能够高效地重构燃料棒的振动响应,还能够判断每个DMD模态的稳定性。 展开更多
关键词 pod DMD 流致振动 模态 燃料棒
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基于MSSA的PSS与UPFC-POD参数和UPFC位置协调优化 被引量:3
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作者 和萍 云磊 +2 位作者 赵琛 王明洋 潘志文 《电力系统保护与控制》 EI CSCD 北大核心 2024年第1期174-187,共14页
针对风火打捆(wind-thermal-bundled,WTB)系统在受到干扰时可能由于阻尼不足而出现的低频振荡现象以及较高的网损会导致运行成本的增加和阻碍“双碳”目标实现的问题,提出了一种电力系统稳定器(power system stabilizer,PSS)与统一潮流... 针对风火打捆(wind-thermal-bundled,WTB)系统在受到干扰时可能由于阻尼不足而出现的低频振荡现象以及较高的网损会导致运行成本的增加和阻碍“双碳”目标实现的问题,提出了一种电力系统稳定器(power system stabilizer,PSS)与统一潮流控制器(unified power flow controller,UPFC)附加功率振荡阻尼控制器(power oscillation damping,POD)参数和UPFC安装位置协调优化策略方法。首先,基于Matlab构建了风火打捆外送系统和控制器模型。然后,利用多目标樽海鞘优化算法(multi-objective salp swarm algorithm,MSSA),将协调优化问题转化为多目标优化问题。目标函数设计中考虑了UPFC装置的调节特性。最后,采用IEEE 4机2区系统和16机5区系统进行多种工况下的仿真。仿真结果显示,协调优化后的控制器可以提高系统阻尼,维持发电机转速的稳定,抑制低频振荡引起的系统有功、电压等的波动,同时降低了系统的有功网损,提高了系统稳定性和运行经济性。MSSA在工程问题上的应用得到了补充。 展开更多
关键词 风火打捆 低频振荡 PSS UPFC-pod 安装位置 运行经济性
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基于POD方法的水下航行器振动响应快速求解
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作者 王衡 路宽 +3 位作者 刘骏 童建忠 郑伟 张康宇 《南京航空航天大学学报》 CAS CSCD 北大核心 2024年第6期1066-1073,共8页
采用本征正交分解(Proper orthogonal decomposition,POD)方法对具有轴承非线性的壳体‑电机‑转子耦合系统进行模型降阶,以降低计算成本。针对壳体‑电机‑转子耦合结构采用有限元法建立起192自由度的转子系统模型。介绍了POD法的基本原理... 采用本征正交分解(Proper orthogonal decomposition,POD)方法对具有轴承非线性的壳体‑电机‑转子耦合系统进行模型降阶,以降低计算成本。针对壳体‑电机‑转子耦合结构采用有限元法建立起192自由度的转子系统模型。介绍了POD法的基本原理及其在壳体‑电机‑转子耦合系统中的具体表达。通过应用POD方法,壳体‑电机‑转子耦合系统分别减少到20、18和15个自由度,计算时间降低94%以上,且对比了简化系统和原系统的时间历程曲线和频谱,证明了POD方法的高效性和准确性。 展开更多
关键词 水下航行器 非线性系统 本征正交分解方法
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Assessing the Efficacy of Lemongrass (Cymbopogon citratus) and Sambong (Blumea balsamifera) Extracts in Combating Black Pod Disease: Sustainable Solutions for Controlling Phytophthora megakarya in Cameroon’s Cocoa Plantations
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作者 Gertrude Membang James Michel Tchotet Tchoumi +5 位作者 Godswill Ntsomboh Ntsefong Emmanuel Yvan Mba Ela Sylvere Landry Lontsi Dida Ludovic Tchuenkam Tsango Pascal Loïc Ekango Mbondjo Fritz Oben Tabi 《American Journal of Plant Sciences》 CAS 2024年第7期519-537,共19页
The use of plant extracts as antifungal agents is gaining increasing attention, particularly for the control of black pod disease in cocoa. Despite extensive research, current strategies haven’t been entirely effecti... The use of plant extracts as antifungal agents is gaining increasing attention, particularly for the control of black pod disease in cocoa. Despite extensive research, current strategies haven’t been entirely effective. This study evaluated the effectiveness of Cymbopogon citratus and Blumea balsamifora leaf extracts, both individually and in combination, against Phytophthora megakarya. We assessed the efficacy of the most promising combination (75% B. balsamifera, 25% C. citratus) after storage at room temperature for up to 9 days. Agar microdilution and in vivo bioassays were conducted to determine antifungal susceptibility and effectiveness. Blumea extract exhibited the highest overall inhibitory activity, with the lowest minimum inhibitory concentration (117 µl mL−1) while C. citratus had a narrower range of MIC (146 to 233 µl mL−1). The combination of C. citratus and B. balsamifera demonstrated a synergistic effect against P. megakarya, achieving growth inhibition on V8 media (92.72 ± 4.20% to 100%) and on artificially infected detached pod cortex (92.24 ± 4.53% to 98.75 ± 1.25%), which was not significantly different from the positive control (Ridomil). Furthermore, this combination maintained its effectiveness for up to 9 days at room temperature. These findings suggest that combining plant extracts can enhance their antifungal properties. 展开更多
关键词 Plant Extracts Antifungal Agents Synergistic Effect Black pod Disease Cocoa
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