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融合知识图谱与多模态感知的Linux实验课程评价体系研究
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作者 杨程程 陈勇 +3 位作者 李晟 闫大顺 刘同来 呼增 《电脑与电信》 2025年第9期63-67,74,共6页
Linux实验课程是计算机类与信息类专业基础核心课程,具有较强的实践性和复杂的操作链条。传统评价系统多依赖学生提交的实验报告,存在结果导向强、缺乏过程分析、情境感知能力不足等问题,难以全面、动态地反映学生实际能力与学习状态。... Linux实验课程是计算机类与信息类专业基础核心课程,具有较强的实践性和复杂的操作链条。传统评价系统多依赖学生提交的实验报告,存在结果导向强、缺乏过程分析、情境感知能力不足等问题,难以全面、动态地反映学生实际能力与学习状态。为此,提出一种融合知识图谱与多模态感知的Linux实验课程评价体系,通过融合代码行为分析、语音与表情情感识别、系统操作轨迹提取和知识图谱推理等关键技术,构建覆盖“教—学—评”全过程的智能化评价机制。系统以学生行为日志、语音答辩、表情图像、操作流程、错误类型为多模态输入,利用焦点对比学习机制与Neo4j知识图谱模型实现综合评分与个性化反馈。实验结果表明,该体系在评价准确性、一致性、学生学习动机激发成效等方面取得显著提升,可为Linux等系统类实验课程的教学改革提供新范式与技术支撑。 展开更多
关键词 Linux实验课程 知识图谱 多模态感知 焦点对比学习
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基于土拱效应和黄土改进应变楔模型的抗滑桩水平承载力计算
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作者 罗丽娟 任翔 +2 位作者 李晟 唐涌 贺鹏远 《上海交通大学学报》 北大核心 2026年第1期163-174,共12页
滑坡防治是当前地质灾害研究的热点之一,桩前被动土拱效应是影响抗滑桩水平承载力的重要因素.目前,考虑桩前被动土拱效应对抗滑桩桩身受力影响的研究尚不多见.在当前应变楔模型研究的基础上,对抗滑桩嵌固段的桩前被动土拱效应及土拱受... 滑坡防治是当前地质灾害研究的热点之一,桩前被动土拱效应是影响抗滑桩水平承载力的重要因素.目前,考虑桩前被动土拱效应对抗滑桩桩身受力影响的研究尚不多见.在当前应变楔模型研究的基础上,对抗滑桩嵌固段的桩前被动土拱效应及土拱受力特点进行了分析,建立了考虑桩前被动土拱效应的排桩改进应变楔模型,并验证了其有效性.引入桩前被动土拱并分析了被动土拱的受力特点,提出以被动土拱的破坏作为桩前土体破坏的判定条件;将群桩应变楔模型的前置计算宽度修正为1倍桩间距,可使排桩的被动土拱受力分析更加合理;考虑桩前土静止侧向压力对桩前土体和桩-土相互作用的影响,能使桩前被动土拱的土体应力状态求解更加合理,并使桩身内力与变形计算结果更为准确.所提出的排桩改进应变楔模型能够更准确地反映邻桩相互作用时桩前土抗力的变化规律,研制的排桩内力和变形优化迭代计算程序可成为实际工程计算的新选择. 展开更多
关键词 抗滑桩 被动土拱 改进应变楔 水平承载力 黄土
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琼北地区活断层土壤氡地球化学特征
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作者 李盛 周雯 +5 位作者 张慧 王惠琳 黄章荣 江蕾 解晓静 郭昱琴 《地震科学进展》 2026年第1期16-23,共8页
本文收集整理了琼北地区2020—2022年7条3期活断层土壤氡测线的观测数据资料,统计了各测线土壤逸出氡浓度的均值、异常阈值和超阈值的测点数,分析了3年期间各测线的土壤逸出氡浓度变化特征。结果表明:2020—2022年7条测线土壤逸出氡浓... 本文收集整理了琼北地区2020—2022年7条3期活断层土壤氡测线的观测数据资料,统计了各测线土壤逸出氡浓度的均值、异常阈值和超阈值的测点数,分析了3年期间各测线的土壤逸出氡浓度变化特征。结果表明:2020—2022年7条测线土壤逸出氡浓度变化均较为符合跨正断活断层的土壤氡浓度的变化特征;除2020年金康路测线无测点超阈值外,其余测线每年的观测值均存在超阈值的现象,但所超阈值线的幅度均较小,且测线超阈值的测点数也较少;7条测线所在3条活断层的活动危险性较低。本文首次建立了琼北地区活断层周边土壤氡浓度的时空数据库,明确了活断层附近土壤氡背景值范围是8500~33000 Bq/m^(3),为后续地震前兆识别提供基线参考。 展开更多
关键词 活断层 土壤逸出氡 测线 阈值 异常信号
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Impact of admission-blood-glucose-to-albumin ratio on allcause mortality and renal prognosis in critical patients with coronary artery disease: insights from the MIMIC-IV database
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作者 Yong HONG Bo-Wen ZHANG +9 位作者 Jing SHI Ruo-Xin MIN Ding-Yu WANG Jiu-Xu KAN Yun-Long GAO lin-Yue PENG Ming-Lu XU Ming-Ming WU Yue li li sheng 《Journal of Geriatric Cardiology》 2025年第6期563-577,共15页
BACKGROUND Blood glucose and serum albumin have been associated with cardiovascular disease prognosis,but the impact of admission-blood-glucose-to-albumin ratio(AAR)on adverse outcomes in critical ill coronary artery ... BACKGROUND Blood glucose and serum albumin have been associated with cardiovascular disease prognosis,but the impact of admission-blood-glucose-to-albumin ratio(AAR)on adverse outcomes in critical ill coronary artery disease(CAD)patients was not investigated.METHODS Patients diagnosed with CAD were non-consecutively selected from the MIMIC-IV database and categorized into quartiles based on their AAR.The primary outcome was 1-year mortality,and secondary endpoints were in-hospital mortality,acute kidney injury(AKI),and renal replacement therapy(RRT).A restricted cubic splines model and Cox proportional hazard models assessed the association between AAR and adverse outcomes in CAD patients.Kaplan-Meier survival analysis determined differences in endpoints across subgroups.RESULTS A total of 8360 patients were included.There were 726 patients(8.7%)died in the hospital and 1944 patients(23%)died at 1 year.The incidence of AKI and RRT was 63%and 4.3%,respectively.High AAR was markedly associated with in-hospital mortality(HR=1.587,P=0.003),1-year mortality(HR=1.502,P<0.001),AKI incidence(HR=1.579,P<0.001),and RRT(HR=1.640,P<0.016)in CAD patients in the completely adjusted Cox proportional hazard model.Kaplan-Meier survival analysis noted substantial differences in all endpoints based on AAR quartiles.Stratified analysis and interaction test demonstrated stable correlations between AAR and outcomes.CONCLUSIONS The results highlight that AAR may be a potential indicator for assessing in-hospital mortality,1-year mortality,and adverse renal prognosis in critical CAD patients. 展开更多
关键词 blood glucose critical patients coronary artery disease coronary artery admission blood glucose albumin ratio kidney injur all cause mortality serum albumin
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A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty
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作者 Cui Jiawei Che Ailan +1 位作者 li sheng Cheng Yongfeng 《Earthquake Engineering and Engineering Vibration》 2025年第1期169-186,共18页
Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee th... Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this study.The proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical equipment.Then,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed method.The results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure probability.The seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility curve.Furthermore,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence. 展开更多
关键词 seismic fragility UNCERTAINTY logistic lasso regression ±1000 kV main transformer sensitivity analysis
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Adaptive Fault-Tolerant Control for Unknown Affine Nonlinear Systems Based on Self-Organizing RBF Neural Network
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作者 Ran Chen Donghua Zhou li sheng 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1788-1800,共13页
This article presents an adaptive fault-tolerant tracking control strategy for unknown affine nonlinear systems subject to actuator faults and external disturbances.To address the hyperparameter initialization challen... This article presents an adaptive fault-tolerant tracking control strategy for unknown affine nonlinear systems subject to actuator faults and external disturbances.To address the hyperparameter initialization challenges inherent in conventional neural network training,an improved self-organizing radial basis function neural network(SRBFNN)with an input-dependent variable structure is developed.Furthermore,a novel selforganizing RBFNN-based observer is introduced to estimate system states across all dimensions.Leveraging the reconstructed states,the proposed adaptive controller effectively compensates for all uncertainties,including estimation errors in the observer,ensuring accurate state tracking with reduced control effort.The uniform ultimate boundedness of all closed-loop signals and tracking errors is rigorously established via Lyapunov stability analysis.Finally,simulations on two different nonlinear systems comprehensively validate the effectiveness and superiority of the proposed control approach. 展开更多
关键词 Adaptive tracking control fault-tolerant control self-organizing radial basis function neural network(SRBFNN) unknown affine nonlinear system
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基于自适应SLIC的岩心图像背景分割 被引量:1
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作者 陈国军 李胜 +1 位作者 尹鹏 滕一诺 《计算机与数字工程》 2021年第12期2639-2642,2664,共5页
针对岩心CT图像中岩心区域与背景区域边界模糊,现有的分割方法无法有效分割出岩心区域,影响数字岩心模型的准确性问题,论文提出了基于改进线性迭代聚类(SLIC)的岩心背景分割算法优化分割效果。首先以图像复杂度为依据,得出图像预分割的... 针对岩心CT图像中岩心区域与背景区域边界模糊,现有的分割方法无法有效分割出岩心区域,影响数字岩心模型的准确性问题,论文提出了基于改进线性迭代聚类(SLIC)的岩心背景分割算法优化分割效果。首先以图像复杂度为依据,得出图像预分割的超像素个数;其次对岩心和背景区域的相似超像素进行区域合并,减少后续冗余计算;最后根据岩心像素与背景像素区域像素值差异分割岩心背景。实验结果表明,论文算法有效分割出岩心区域,避免了阈值法分割对岩心区域的破坏,减少了用户干预,在解决岩心背景分割的完整性和有效性方面表现出了良好的性能。 展开更多
关键词 图像分割 图像复杂度 超像素 区域合并 背景分割
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煤化工产业的高质量发展观
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作者 魏贤勇 宗志敏 +22 位作者 樊星 何晓燕 白翔 伊尔夏提·地里夏提 赵炜 倪中海 曹景沛 丛兴顺 赵云鹏 亢玉红 王爱民 高勇 莫文龙 徐美玲 梁静 赵小燕 柳方景 刘中秋 刘光辉 麻志浩 李胜 李莉 李壮 《石油学报(石油加工)》 北大核心 2026年第1期285-298,共14页
高质量发展应以最少的资源(特别是化石资源)消耗和最低的污染排放创造最大经济和社会效益,是中国经济社会长期发展的主旋律。作为中国目前的主要能源,煤炭在为国民经济的发展提供动力的同时也造成严重的环境污染,成为中国二氧化碳、硫... 高质量发展应以最少的资源(特别是化石资源)消耗和最低的污染排放创造最大经济和社会效益,是中国经济社会长期发展的主旋律。作为中国目前的主要能源,煤炭在为国民经济的发展提供动力的同时也造成严重的环境污染,成为中国二氧化碳、硫氧化物和氮氧化物排放的主要来源。煤中有机质富含芳环(特别是缩合芳环)和杂原子,作为洁净能源利用先天不足,但作为获取高值乃至高端化学品的原料利用得天独厚。现有煤化工产业高投入、高污染和低产出的生产模式难以为继,亟待转型。煤作为形成周期超过7000万年的不可再生化石资源,既不应简单焚烧,也不宜在苛刻条件和大量排放污染物的情况下转化成为低值产品。着力发展非化石能源替代以煤为主的化石能源是中国实现碳中和的根本出路。从煤中有机质的组成结构看,煤是获取特效药物和染料与高端功能性材料用的芳香族化合物(特别是缩合芳香族化合物)的重要原料。煤化工产业的高质量发展应遵循少用、精用和巧用原则,大力开发温和条件下定向转化煤中有机质为高端化学品的关键技术,形成煤炭资源高值化利用的产业链,助力国家整体的高质量发展。 展开更多
关键词 高质量发展 煤化工产业 温和条件 定向转化 高端化学品
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Clinical Application of Fetal Umbilical Vein Doppler Parameters in Maternal Preeclampsia
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作者 li sheng Wei Xu Jiehao Huang 《Yangtze Medicine》 2021年第4期295-302,共8页
<strong>Objective:</strong> To observe the changes of fetal umbilical vein (UV) Doppler parameters in pregnant women with preeclampsia (PE) and analyze their predictive values for maternal PE. <strong&g... <strong>Objective:</strong> To observe the changes of fetal umbilical vein (UV) Doppler parameters in pregnant women with preeclampsia (PE) and analyze their predictive values for maternal PE. <strong>Methods:</strong> Forty-six patients with PE who underwent systematic ultrasound examination in our hospital from December 2017 to May 2021 were included as the subjects, which were divided into two groups according to the severity of the disease (23 cases in each group). And 120 normal pregnant women who underwent health examination in our hospital during the same period were enrolled as the control group. Color Doppler ultrasonography was used to monitor the umbilical vein flow (QUV), left portal vein flow (QLPV), venous catheter flow (QDV), left portal vein (LPV) shunt rate and venous catheter (DV) shunt rate. And the sensitivity and specificity of the related indexes were calculated and analyzed according to the gold standard for clinical diagnosis of PE. <strong>Results:</strong> As the severity of PE increased, the fetal QUV, QLPV and LPV shunt rates decreased, and the QDV and DV shunt rates increased, with statistically significant differences compared with the control group (P < 0.05). The specificity and sensitivity of the combination of fetal QUV, QLPV, QDV, LPV shunt rate and DV shunt rate in predicting PE were higher than those of the indexes used alone (P < 0.05). <strong>Conclusion:</strong> The fetal umbilical vein Doppler parameters QUV, QLPV, QDV, LPV shunt rate, and DV shunt rate have some value in predicting PE, but their combination showed greater value, as well as higher diagnostic and clinical significance. 展开更多
关键词 Fetal Umbilical Vein Doppler Parameters PREECLAMPSIA
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三大主粮作物产量对施加生物炭的响应
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作者 朱银浩 李升 +4 位作者 尹娟 杨莹攀 杜斌 范家杨 李东宇 《环境科学》 北大核心 2026年第1期543-552,共10页
为探明施加生物炭对全球三大主粮作物产量的变化规律,以192篇文献,1 093条试验数据为研究对象,通过Meta分析定量探讨了气候条件、土壤理化性质、生物炭特性和施加量对作物产量的影响.结果表明,与不施加生物炭相比,施加生物炭总体提高作... 为探明施加生物炭对全球三大主粮作物产量的变化规律,以192篇文献,1 093条试验数据为研究对象,通过Meta分析定量探讨了气候条件、土壤理化性质、生物炭特性和施加量对作物产量的影响.结果表明,与不施加生物炭相比,施加生物炭总体提高作物产量15.6%,玉米、小麦和水稻分别提高了14.4%、15.5%和16.4%.土壤有机碳、全氮、有机质、碳氮比、生物炭中有机碳和全氮含量对三大主粮作物产量影响最显著.通过随机森林模型分析,生物炭裂解温度对玉米和水稻的产量影响相对不重要,年平均降雨量对小麦的产量影响相对不重要,此时玉米、小麦和水稻的决定系数R^(2)分别为0.795、0.656和0.856.研究结果可为今后作物生产合理施用生物炭提供参考依据,有助于促进全球农业生产绿色发展. 展开更多
关键词 生物炭 作物产量 META分析 随机森林模型 全球尺度
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锰掺杂对(K_(0.5)Na_(0.5))NbO_(3)-LiNbO_(3)压电陶瓷结构和性能的影响 被引量:1
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作者 李圣 谷良贤 唐福生 《材料导报》 EI CAS CSCD 北大核心 2009年第22期9-11,共3页
采用传统陶瓷制备工艺制备了(K_(0.5)Na_(0.5))NbO_(3)-LiNbO_(3)-xMnO_(2)压电陶瓷,分析了陶瓷样品的微观组织结构。实验结果表明,随MnO_(2)掺杂量的增多,陶瓷由四方相转变为正交相,晶粒的均匀性下降并生成K_(3)LiNb_(6)O_(17)相。研究... 采用传统陶瓷制备工艺制备了(K_(0.5)Na_(0.5))NbO_(3)-LiNbO_(3)-xMnO_(2)压电陶瓷,分析了陶瓷样品的微观组织结构。实验结果表明,随MnO_(2)掺杂量的增多,陶瓷由四方相转变为正交相,晶粒的均匀性下降并生成K_(3)LiNb_(6)O_(17)相。研究了MnO_(2)不同掺杂量对陶瓷压电性能的影响。结果表明,随锰掺杂量的增加,材料逐渐变"硬",机电耦合系数k_(p)和压电常数d_(33)逐渐减小,同时Q_(m)逐渐增大;当MnO_(2)含量为0.8%(质量分数)时,陶瓷的机械品质因数达到最大,此时陶瓷的压电性能为:k_(p)=0.34,k_(t)=0.43,d_(33)=110pC/N,Q_(m)=401.3。 展开更多
关键词 铌酸钾钠-铌酸锂陶瓷 锰掺杂 压电性能 机械品质因数
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中国兽类名录(2024版) 被引量:23
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作者 魏辅文 杨奇森 +28 位作者 吴毅 蒋学龙 刘少英 胡义波 葛德燕 李保国 杨光 李明 周江 李松 李晟 余文华 陈炳耀 张泽钧 周材权 吴诗宝 张立 陈中正 陈顺德 邓怀庆 江廷磊 张礼标 石红艳 卢学理 李权 刘铸 崔雅倩 李玉春 何锴 《兽类学报》 北大核心 2025年第1期1-16,共16页
自“中国兽类名录(2021版)”和《中国兽类分类与分布》问世以来,这两项工作在国际和国内的哺乳动物研究以及保护生物学领域引起了极大的关注。得益于国家重大研究计划的支持,例如第二次青藏高原综合科学考察研究,国内的生物本底资源得... 自“中国兽类名录(2021版)”和《中国兽类分类与分布》问世以来,这两项工作在国际和国内的哺乳动物研究以及保护生物学领域引起了极大的关注。得益于国家重大研究计划的支持,例如第二次青藏高原综合科学考察研究,国内的生物本底资源得到了进一步的明确,中国哺乳动物分类学的研究也在持续进步。在2022—2024年,一系列新的研究成果相继发表,与2022年相比,新增42个物种。为了帮助国内外学者全面了解中国哺乳动物的有效种类及其详细信息,我们对“中国兽类名录(2021版)”及《中国兽类分类与分布》涉及的中国兽类物种名录进行了更新。截至2024年12月,中国记录的兽类有效种类包括58科,263属,736种。 展开更多
关键词 哺乳动物 物种数目 分类学 名录 中国
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Performance of transient elastography in assessing liver fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis overlap syndrome 被引量:19
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作者 Hui-Min Wu li sheng +8 位作者 Qi Wang Han Bao Qi Miao Xiao Xiao Can-Jie Guo Hai li Xiong Ma De-Kai Qiu Jing Hua 《World Journal of Gastroenterology》 SCIE CAS 2018年第6期737-743,共7页
AIM To investigate the performance of transient elastography(TE) for diagnosis of fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis(AIHPBC) overlap syndrome.METHODS A total of 70 patients with... AIM To investigate the performance of transient elastography(TE) for diagnosis of fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis(AIHPBC) overlap syndrome.METHODS A total of 70 patients with biopsy-proven AIH-PBC overlap syndrome were included. Spearman correlation test was used to analyze the correlation of liver stiffness measurement(LSM) and fibrosis stage. Independent samples Student's t-test or one-way analysis of variance was used to compare quantitative variables. Receiver operating characteristics(ROC) curve was used to calculate the optimal cut-off values of LSM for predicting individual fibrosis stages. A comparison on the diagnostic accuracy for severe fibrosis was made between LSM and other serological scores.RESULTS Patients with AIH-PBC overlap syndrome had higher median LSM than healthy controls(11.3 ± 6.4 k Pa vs 4.3 ± 1.4 k Pa, P < 0.01). LSM was significantly correlated with fibrosis stage(r = 0.756, P < 0.01). LSM values increased gradually with an increased fibrosis stage. The areas under the ROC curves of LSM for stages F ≥ 2, F ≥ 3, and F4 were 0.837(95%CI: 0.729-0.914), 0.910(0.817-0.965), and 0.966(0.893-0.995), respectively. The optimal cut-off values of LSM for fibrosis stages F ≥ 2, F ≥ 3, and F4 were 6.55, 10.50, and 14.45 k Pa, respectively. LSM was significantly superior to fibrosis-4, glutaglumyl-transferase/platelet ratio, and aspartate aminotransferase-to-platelet ratio index scores in detecting severe fibrosis(F ≥ 3)(0.910 vs 0.715, P < 0.01; 0.910 vs 0.649, P < 0.01; 0.910 vs 0.616, P < 0.01, respectively).CONCLUSION TE can accurately detect hepatic fibrosis as a noninvasive method in patients with AIH-PBC overlap syndrome. 展开更多
关键词 LIVER stiffness measurement Transient elastography LIVER fibrosis AUTOIMMUNE hepatitis PRIMARY BILIARY CHOLANGITIS Overlap syndrome
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工作面地层序列多钻孔信息综合表征与分布规律研究
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作者 张彪 朱泽斌 +7 位作者 柴君锋 吴海勇 宋嘉珺 李红飞 李生 刘志鹏 高龙祥 芮旭升 《煤》 2026年第1期88-93,共6页
明确工作面上覆地层结构是揭示采矿岩层运移规律的重要基础。鉴于山西某矿在2311工作面地表300 m×587 m范围内密集施工了27个钻孔,采用MATLAB编程识别了钻孔的综合测井成果,对钻孔柱状进行了批量图像化生成,并形成了地质钻孔数据矩... 明确工作面上覆地层结构是揭示采矿岩层运移规律的重要基础。鉴于山西某矿在2311工作面地表300 m×587 m范围内密集施工了27个钻孔,采用MATLAB编程识别了钻孔的综合测井成果,对钻孔柱状进行了批量图像化生成,并形成了地质钻孔数据矩阵;提出了钻孔区域表征方法,并自编程序解译了煤系地层结构剖面;最后给出了研究区域地质剖面的代表性参数,揭示了区域地层结构的分布特征。研究结果表明:①对推进方向钻孔剖面结构特征处理分析,整体地层从南向北出现下沉趋势,在ZK11—ZK13钻孔之间出现了较为明显的倾角,与实际的煤层底板等高线显示的结果一致;②研究区域地层结构具有典型的“砂岩群”特征,是地层承载的主体,可划为G1~G4四个群,砂岩群中心位置埋深分别在-90 m、-150 m、-200 m和-270 m左右。文章旨在通过笔者获取的宝贵地质钻孔数据,利用自主研发的matlab对钻孔数据进行图像化数字化表征,对推进方向煤系地层结构的特征研究进行分析,以期为相关研究提供一定的参考和借鉴。 展开更多
关键词 工作面开采 上覆岩层结构 砂岩群组 连续性
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水泥混凝土桥面水性环氧沥青防水黏结层性能及其应用研究
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作者 李胜 周刚博 +2 位作者 李亮亮 金亚龙 王书涛 《建筑机械》 2026年第1期330-335,共6页
桥面防水层对桥面防水起关键作用。水性环氧沥青材料具有优良的力学性能和防水性,而且工程施工方便。文章结合武汉新城至黄石新港快速通道下陆区段铜都大道高架桥项目,通过剪切试验和拉拔试验,研究水性环氧沥青用量对黏结层黏结强度的... 桥面防水层对桥面防水起关键作用。水性环氧沥青材料具有优良的力学性能和防水性,而且工程施工方便。文章结合武汉新城至黄石新港快速通道下陆区段铜都大道高架桥项目,通过剪切试验和拉拔试验,研究水性环氧沥青用量对黏结层黏结强度的影响。试验研究结果表明,水性环氧沥青防水黏结材料的施工温度控制在5~35℃,洒布用量为0.8~1.2 kg/m^(2),最佳使用量为1.0 kg/m^(2)。 展开更多
关键词 水泥混凝土桥面 水性环氧 沥青防水材料 黏结性能
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RVO继发黄斑水肿患者雷珠单抗玻璃体腔注射后脉络膜组织形态及血流灌注变化 被引量:4
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作者 祁媛媛 许致玉 +3 位作者 李春实 张智健 李胜 张立军 《中华实验眼科杂志》 北大核心 2025年第1期52-59,共8页
目的观察玻璃体腔注射雷珠单抗后视网膜静脉阻塞(RVO)继发黄斑水肿患者脉络膜组织形态及血流灌注的变化。方法采用队列研究方法,纳入2022年1月至2023年6月在大连市第三人民医院就诊的单眼急性期RVO继发黄斑水肿患者157例157眼,其中视网... 目的观察玻璃体腔注射雷珠单抗后视网膜静脉阻塞(RVO)继发黄斑水肿患者脉络膜组织形态及血流灌注的变化。方法采用队列研究方法,纳入2022年1月至2023年6月在大连市第三人民医院就诊的单眼急性期RVO继发黄斑水肿患者157例157眼,其中视网膜中央静脉阻塞(CRVO)患者66例66眼,视网膜分支静脉阻塞(BRVO)患者91例91眼,均采用雷珠单抗3+pro re nata(PRN)的方法进行治疗。分别于注射前及每次注射后1个月使用光学相干断层扫描仪(OCT)测量黄斑中心视网膜厚度;使用OCT加强深度扫描模式获得清晰的脉络膜图像,并测量黄斑中心凹下脉络膜厚度(SFCT)、黄斑中心凹鼻侧1500μm处脉络膜厚度(CT N1.5 mm)、黄斑中心凹颞侧1500μm处脉络膜厚度(CT T1.5 mm),计算黄斑中心区域平均脉络膜厚度(CT Mean);使用ImageJ软件对脉络膜图像进行二值化处理,定量分析脉络膜血管管腔面积(LA)、脉络膜基质面积(SA)、脉络膜总面积(TCA)和脉络膜血管指数(CVI)。结果RVO患眼基线SFCT、CT T1.5 mm、CT N1.5 mm、CT Mean、LA、SA、TCA、CVI均较对侧眼升高,差异均有统计学意义(均P<0.01)。CRVO组患眼基线CT Mean为(326.99±64.92)μm,大于BRVO组的(299.80±73.08)μm,差异有统计学意义(t=2.41,P=0.02);CRVO组和BRVO组基线CVI值分别为(72.50±5.62)%和(72.33±5.85)%,差异无统计学意义(t=0.187,P=0.85)。在RVO、CRVO或BRVO患者中,每次注射后SFCT、CT T1.5 mm、CT N 1.5 mm、CT Mean、LA、SA、TCA、CVI均较基线降低,差异均有统计学意义(均P<0.01)。CRVO患眼第2次注射后LA和CVI与第1次注射后比较,差异无统计学意义(均P>0.05),其余SFCT、CT T1.5 mm、CT N1.5 mm、CT Mean、SA、TCA均低于第1次注射后值,差异有统计学意义(均P<0.05);BRVO患眼第2次注射后SA和CVI与第1次注射后比较,差异无统计学意义(均P>0.05),其余SFCT、CT T1.5 mm、CT N1.5 mm、CT Mean、LA、TCA均低于第1次注射后值,差异有统计学意义(均P<0.05)。各类型RVO患眼第2次注射与第3次注射后SFCT、CT T1.5 mm、CT N1.5 mm、CT Mean、SA、TCA、CVI比较,差异均无统计学意义(均P>0.05)。结论玻璃体腔注射雷珠单抗后,RVO继发黄斑水肿患眼脉络膜厚度变薄、CVI减小,并在第2次注射后保持相对稳定。 展开更多
关键词 视网膜静脉阻塞 脉络膜厚度 脉络膜血流指数 雷珠单抗 抗血管内皮生长因子
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Sheltering effect of punched steel plate sand fences for controlling blown sand hazards along the Golmud-Korla Railway:Field observation and numerical simulation studies 被引量:5
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作者 ZHANG Kai TIAN Jianjin +2 位作者 QU Jianjun ZHAO liming li sheng 《Journal of Arid Land》 SCIE CSCD 2022年第6期604-619,共16页
Sand fences made of punched steel plate(PSP)have recently been applied to control wind-blown sand in desertified and Gobi areas due to their strong wind resistance and convenient in situ construction.However,few studi... Sand fences made of punched steel plate(PSP)have recently been applied to control wind-blown sand in desertified and Gobi areas due to their strong wind resistance and convenient in situ construction.However,few studies have assessed the protective effect of PSP sand fences,especially through field observations.This study analyzes the effects of double-row PSP sand fences on wind and sand resistance using field observations and a computational fluid dynamics(CFD)numerical simulation.The results of field observations showed that the average windproof efficiencies of the first-row and second-row sand fences were 79.8%and 70.8%,respectively.Moreover,the average windproof efficiencies of the numerical simulation behind the first-row and second-row sand fences were 89.8%and 81.1%,respectively.The sand-resistance efficiency of the double-row PSP sand fences was 65.4%.Sand deposition occurred close to the first-row sand fence;however,there was relatively little sand on the leeward side of the second-row sand fence.The length of sand accumulation near PSP sand fences obtained by numerical simulation was basically consistent with that through field observations,indicating that field observations combined with numerical simulation can provide insight into the complex wind-blown sand field over PSP sand fences.This study indicates that the protection efficiency of the double-row PSP sand fences is sufficient for effective control of sand hazards associated with extremely strong wind in the Gobi areas.The output of this work is expected to improve the future application of PSP sand fences. 展开更多
关键词 punched steel plate sheltering effect field observations computational fluid dynamics numerical simulation windproof efficiency
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A Feature Weighted Mixed Naive Bayes Model for Monitoring Anomalies in the Fan System of a Thermal Power Plant 被引量:5
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作者 Min Wang li sheng +1 位作者 Donghua Zhou Maoyin Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第4期719-727,共9页
With the increasing intelligence and integration,a great number of two-valued variables(generally stored in the form of 0 or 1)often exist in large-scale industrial processes.However,these variables cannot be effectiv... With the increasing intelligence and integration,a great number of two-valued variables(generally stored in the form of 0 or 1)often exist in large-scale industrial processes.However,these variables cannot be effectively handled by traditional monitoring methods such as linear discriminant analysis(LDA),principal component analysis(PCA)and partial least square(PLS)analysis.Recently,a mixed hidden naive Bayesian model(MHNBM)is developed for the first time to utilize both two-valued and continuous variables for abnormality monitoring.Although the MHNBM is effective,it still has some shortcomings that need to be improved.For the MHNBM,the variables with greater correlation to other variables have greater weights,which can not guarantee greater weights are assigned to the more discriminating variables.In addition,the conditional P(x j|x j′,y=k)probability must be computed based on historical data.When the training data is scarce,the conditional probability between continuous variables tends to be uniformly distributed,which affects the performance of MHNBM.Here a novel feature weighted mixed naive Bayes model(FWMNBM)is developed to overcome the above shortcomings.For the FWMNBM,the variables that are more correlated to the class have greater weights,which makes the more discriminating variables contribute more to the model.At the same time,FWMNBM does not have to calculate the conditional probability between variables,thus it is less restricted by the number of training data samples.Compared with the MHNBM,the FWMNBM has better performance,and its effectiveness is validated through numerical cases of a simulation example and a practical case of the Zhoushan thermal power plant(ZTPP),China. 展开更多
关键词 Abnormality monitoring continuous variables feature weighted mixed naive Bayes model(FWMNBM) two-valued variables thermal power plant
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超级微波消解ICP-OES法测定宠物饲料中硫含量及与总蛋白质相关性分析 被引量:1
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作者 陈树娣 李锦才 +3 位作者 陈晓燕 李胜 张世伟 郑彦婕 《光谱学与光谱分析》 北大核心 2025年第2期420-425,共6页
建立了超级微波消解-电感耦合等离子体发射光谱法(ICP-OES)测定宠物饲料中硫含量的新方法。系统探究了超级微波消解条件对消解液中残留碳含量(RCC)和残留酸量(RA)的影响,以这两项指标为依据,有效评估了消解效果,建立了优化微波消解条件... 建立了超级微波消解-电感耦合等离子体发射光谱法(ICP-OES)测定宠物饲料中硫含量的新方法。系统探究了超级微波消解条件对消解液中残留碳含量(RCC)和残留酸量(RA)的影响,以这两项指标为依据,有效评估了消解效果,建立了优化微波消解条件的新策略。系统性研究了五种不同价态的硫形态对硫元素测定的影响,发现低价态硫标准物质在酸性条件下制备时,硫元素发射强度显著增强,而高价态硫标准物质在三种条件(酸性、中性和碱性)下制备时,硫元素发射强度均较稳定,为配制介质和硫标准物质的选择提供了有益的指导。研究发现,超级微波消解系统所创造的高温高压环境以及消解试剂的强氧化性条件,能有效消除低价态硫在酸性前处理条件下的发射强度增强效应。采用酸性条件配制高价态硫(SO_(4)^(2-))标准物质,并结合超级微波消解系统,能够实现宠物饲料中五种不同价态硫的准确测定。加标回收率为86.5%~108%,RSD值为1.69%~4.18%,检出限为6.2 mg·kg^(-1),与国家标准方法相比,该方法具有灵敏度高、成本低、绿色环保、工作效率高的优点。研究发现宠物饲料中硫含量与总蛋白质含量之间存在极显著正相关性(相关系数=0.819,p<0.01),可以为宠物饲料中总蛋白质含量的准确测定提供新思路和方向。 展开更多
关键词 超级微波消解 超级微波消解-电感耦合等离子体发射光谱(ICP-OES) 宠物饲料 总蛋白质 相关性
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Prelithiation Enhances Cycling Life of Lithium-Ion Batteries:A Mini Review 被引量:3
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作者 Xiaomei liu Ze Wu +5 位作者 Leqiong Xie li sheng Jianhong liu li Wang Kai Wu Xiangming He 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期1-9,共9页
During the last decade,the rapid development of lithium-ion battery(LIB)energy storage systems has provided significant support for the efficient operation of renewable energy stations.In the coming years,the service ... During the last decade,the rapid development of lithium-ion battery(LIB)energy storage systems has provided significant support for the efficient operation of renewable energy stations.In the coming years,the service life demand of energy storage systems will be further increased to 30 years from the current 20 years on the basis of the equivalent service life of renewable energy stations.However,the life of the present LIB is far from meeting such high demand.Therefore,research on the next-generation LIB with ultra-long service life is imminent.Prelithiation technology has been widely studied as an important means to compensate for the initial coulombic efficiency loss and improve the service life of LIBs.This review systematically summarized the different prelithiation methods from anode and cathode electrodes.Moreover,the large-scale industrialization challenge and the possibility of the existing prelithiation technology are analyzed,based on three key parameters:industry compatibility,prelithiation efficiency,and energy density.Finally,the future trends of improvement in LIB performance by other overlithiated cathode materials are presented,which gives a reference for subsequent research. 展开更多
关键词 cycle life lithium compensation lithium-ion battery prelithiation
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