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Self-management and help-seeking behavior for gastroesophageal reflux symptoms:A population-based survey
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作者 Lotte J Huibertse Jasmijn Sijben +1 位作者 Yonne Peters Peter D Siersema 《World Journal of Gastroenterology》 2026年第2期124-134,共11页
BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is su... BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is suboptimal.Current screening approaches fail to identify individuals not seeking medical consultation for GERS or whose GERS are managed with‘over-the-counter’(OTC)acid suppressant therapies.AIM To assess patients’self-management and help-seeking behavior for GERS.METHODS This cross-sectional study collected data from the Dutch general population aged 18-75 years between January and April 2023 using a web-based survey.The survey included questions regarding self-management(e.g.,use of acid suppressant therapy with or without prescription)and help-seeking behavior(e.g.,consulting a primary care provider)for GERS.Simple random sampling was performed to select individuals within the target age group.In total,18156 randomly selected individuals were invited to participate.The study protocol was registered in ClinicalTrials.gov(identifier:NCT05689918).RESULTS Of the 18156 invited individuals,3214 participants(17.7%)completed the survey,of which 1572 participants(48.9%)reported GERS.Of these,904 participants(57.5%)had never consulted a primary care provider for these symptoms,of which 331 participants(36.6%)reported taking OTC acid suppressant therapy in the past six months and 100 participants(11.1%)fulfilled the screening criteria for BE and EAC according to the European Society of Gastrointestinal Endoscopy Guideline.CONCLUSION The population fulfilling the screening criteria for BE and EAC is incompletely identified,suggesting potential underutilization of medical consultation.Raising public awareness of GERS as a risk factor for EAC is needed. 展开更多
关键词 Gastroesophageal reflux disease AWARENESS SELF-MANAGEMENT Help-seeking behavior Health promotion Patientreported outcomes
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基于LSTM-WGAN模型的柱塞-泡排复合排采系统预测控制方法
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作者 赖欣 钱中程 +3 位作者 杨肖 刘永辉 叶长青 王强 《电子测量与仪器学报》 北大核心 2025年第2期11-20,共10页
高效的生产过程和智能化管理是天然气井可持续发展的关键,目前实际生产中页岩气开采仍然面临着井底积液造成气井产能下降的问题。为提高天然气井的产能和排水效率,充分利用泡沫排水采气和柱塞气举的优点,设计了一套“双元合一”的柱塞-... 高效的生产过程和智能化管理是天然气井可持续发展的关键,目前实际生产中页岩气开采仍然面临着井底积液造成气井产能下降的问题。为提高天然气井的产能和排水效率,充分利用泡沫排水采气和柱塞气举的优点,设计了一套“双元合一”的柱塞-泡排复合排采装置,提出了一种新颖的基于长短期记忆网络(LSTM)和Wasserstein生成对抗网络(WGAN)的复合排采LSTM-WGAN预测控制方法。利用基于密度的抗噪聚类算法(DBSCAN)对数据进行预处理,避免异常数据对模型预测的影响。通过生成器和判别器相互对抗并更新各自梯度方向的权重,不断优化使油套压差、水气比预测值逼近真值,从而准确预测下一时刻的油套压差和水气比。通过柱塞-泡排复合排采智能管理系统,实施预测的柱塞泡排投放策略。实验结果表明,LSTMWGAN模型的误差最小,与LSTM模型相比,LSTM-WGAN模型的油套压差和水气比预测结果的均方根误差、均方误差、平均绝对误差分别降低了2.64%、5.13%、11.75%和8.81%、8.07%、6.60%。LSTM-WGAN预测模型可以准确地预测油套压差和水气比,指导柱塞-泡排复合排采系统发出正确的投放泡排球和柱塞指令,实现了泡排-柱塞的全智能化投放。 展开更多
关键词 复合排采 预测控制 LSTM-WGAN 油套压差 水气比 井底积液
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基于NSGA-Ⅱ和TOPSIS法的横波可控震源振动器平板疲劳寿命优化
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作者 陈振 冉庆杰 +3 位作者 英晓洋 陈能鹏 魏超成 王乔木 《工程设计学报》 北大核心 2025年第2期272-280,共9页
横波可控震源振动器平板作为页岩气勘探中的关键部件,其疲劳寿命直接影响可控震源的使用寿命和勘探精度。然而,传统的振动器平板疲劳寿命优化方法未考虑平板与平板齿间焊接残余应力的影响,导致平板结构在抗疲劳优化设计方面效果不佳。为... 横波可控震源振动器平板作为页岩气勘探中的关键部件,其疲劳寿命直接影响可控震源的使用寿命和勘探精度。然而,传统的振动器平板疲劳寿命优化方法未考虑平板与平板齿间焊接残余应力的影响,导致平板结构在抗疲劳优化设计方面效果不佳。为此,使用局部灵敏度法对平板疲劳寿命进行敏感性分析,确定了焊接残余应力为影响疲劳寿命的关键因素。随后,建立了平板的各向最大焊接残余应力与焊接速度和焊接层间温度之间的数学模型,并以各向最大焊接残余应力为约束,以疲劳寿命为优化目标,建立相应的优化模型。最后,利用NSGA-Ⅱ(nondominated sorting genetic algorithm-Ⅱ,非支配排序遗传算法-Ⅱ)获取Pareto解集,并结合熵权法和TOPSIS(technique for order preference by similarity to ideal solution,逼近理想解排序)法确定最佳优化方案:焊接速度为10.23 mm/s,焊接层间温度为105℃。结果表明,优化后平板的疲劳寿命为10.23年,相比优化前提高了17.72%。研究结果可为横波可控震源振动器平板的疲劳寿命优化提供科学有效的理论方法和工程指导。 展开更多
关键词 横波可控震源 振动器平板 疲劳寿命 焊接残余应力 NSGA-Ⅱ TOPSIS法
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基于FPGA的改进Sobel算子图像实时边缘检测系统
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作者 于波 田亚洲 +1 位作者 任金贝 李华宇 《仪表技术与传感器》 北大核心 2025年第3期116-121,共6页
为了解决嵌入式软件不能对图像进行实时处理以及对带有噪声的图像处理效果不佳的问题,设计了基于改进Sobel算子的图像实时边缘检测系统,该系统在传统Sobel算子的基础上增加了检测方向和角度模板,并结合SCCB传输协议进行实时图像边缘检测... 为了解决嵌入式软件不能对图像进行实时处理以及对带有噪声的图像处理效果不佳的问题,设计了基于改进Sobel算子的图像实时边缘检测系统,该系统在传统Sobel算子的基础上增加了检测方向和角度模板,并结合SCCB传输协议进行实时图像边缘检测,进一步提高视频图像的传输速度和质量。系统以FPGA作为数字主控核心,使用OV5640摄像头采集图像,将采集的图像数据缓存到视频图像处理模块,对该模块进行色彩空间转换和Sobel边缘检测工作,将边缘检测的图像数据缓存到SDRAM读写控制模块,VGA驱动模块从SDRAM中读取数据并控制VGA显示器对边缘检测结果进行显示。实验结果表明:该系统能够完成对图像边缘检测的实时快速精确识别,相较于传统的Sobel算法,改进后的算法在处理复杂图像和噪声点较多的图像方面更有优势,适合低延时以及噪声干扰较为严重的场合。 展开更多
关键词 实时边缘检测 FPGA SCCB SOBEL算子 SDRAM
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OLGA平台下湿气集输管线动态清管模拟
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作者 葛旭 刘斯琦 +4 位作者 张颖 冯波 邬焱灼 杜杰 左丽丽 《油气田地面工程》 2025年第11期24-31,共8页
针对湿气集输管道内积液累积导致的输气效率低下、管道压降增大、能耗急剧攀升及安全隐患凸显等核心问题,依托OLGA瞬态多相流模拟平台,构建了高精度动态清管模型。通过系统模拟分析不同清管输量与旁通率配置下的清管作业过程,深入研究... 针对湿气集输管道内积液累积导致的输气效率低下、管道压降增大、能耗急剧攀升及安全隐患凸显等核心问题,依托OLGA瞬态多相流模拟平台,构建了高精度动态清管模型。通过系统模拟分析不同清管输量与旁通率配置下的清管作业过程,深入研究了清管器运行速度、管道压力动态响应及排液行为的复杂关联机制。研究发现,提高清管输量能够显著提升清管器运行速度并增强其运行稳定性,而精确调控旁通率则对于平衡清管器速度与减少管道出口排液波动至关重要。基于详尽的数据分析与模型验证,推荐在湿气集输管线优化运行中采用15×10^(4)m^(3)/d的清管输量与3%~4%的旁通率作为最优操作参数组合。此成果为湿气集输管线的优化设计与运行提供了重要的理论依据与实践指导。 展开更多
关键词 集输管线 混输 清管 OLGA软件
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Optimizing care for gastric cancer with overt bleeding:Is systemic therapy a valid option?
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作者 Emad Qayed 《World Journal of Clinical Oncology》 2025年第1期1-4,共4页
Gastric cancer(GC)and gastroesophageal junction cancer(GEJC)represent a significant burden globally,with complications such as overt bleeding(OB)further exacerbating patient outcomes.A recent study by Yao et al evalua... Gastric cancer(GC)and gastroesophageal junction cancer(GEJC)represent a significant burden globally,with complications such as overt bleeding(OB)further exacerbating patient outcomes.A recent study by Yao et al evaluated the effectiveness and safety of systematic treatment in GC/GEJC patients presenting with OB.Using propensity score matching,the study balanced the comparison groups to investigate overall survival and treatment-related adverse events.The study's findings emphasize that systematic therapy can be safe and effective and contribute to the ongoing debate about the management of advanced GC/GEJC with OB,highlighting the complexities of treatment decisions in these high-risk patients. 展开更多
关键词 Gastric cancer Overt bleeding Systemic therapy Endoscopic therapy HEMOSTASIS
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重型燃气轮机用新型热障涂层LaMgAl_(11)O_(19)与YSZ涂层抗烧结性能对比
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作者 何磊 邓甜甜 《材料工程》 北大核心 2025年第3期159-168,共10页
随着重型燃气轮机不断升级,燃气轮机透平的进气温度不断提高,传统YSZ涂层已无法满足高于1200℃的服役温度。通过大气等离子喷涂技术制备新型热障涂层LaMgAl_(11)O_(19)(LMA)和YSZ涂层,在1100℃和1300℃进行静态氧化实验,采用SEM和XRD技... 随着重型燃气轮机不断升级,燃气轮机透平的进气温度不断提高,传统YSZ涂层已无法满足高于1200℃的服役温度。通过大气等离子喷涂技术制备新型热障涂层LaMgAl_(11)O_(19)(LMA)和YSZ涂层,在1100℃和1300℃进行静态氧化实验,采用SEM和XRD技术对比分析了不同烧结温度和时长下的孔隙率、微观组织和相变过程。结果表明:LMA涂层在1100℃和1300℃下,孔隙率随烧结时间的延长而增大,YSZ涂层则随烧结时间延长孔隙率明显下降。LMA涂层在高温下短时间内发生相变,断口中可观察到细小的针状晶,随烧结时间的延长,结晶相长大成条状和片状结构,有利于提高涂层的抗烧结性。Rietveld精修结果表明,在1300℃下烧结1000 h,YSZ涂层中T′相含量从82.67%下降至27.69%,C相含量从初始1.50%增加到46.84%,M相含量从0.19%增加到15.39%。此相变过程引起体积转变,产生较大的残余应力,导致涂层脱落。 展开更多
关键词 LaMgAl_(11)O_(19) YSZ 抗烧结 孔隙率 RIETVELD精修
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基于MSIPGAN的地震数据随机噪声压制方法
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作者 罗仁泽 李治岐 《石油物探》 北大核心 2025年第4期653-666,共14页
在地震勘探中,采集得到的地震数据通常会受到严重的随机噪声污染,对后续的数据处理和解释产生负面影响。常规的地震数据噪声压制方法在压制噪声时无法有效分离信号和噪声,导致数据图像细节信息丢失、产生伪纹理等问题。为提高地震图像质... 在地震勘探中,采集得到的地震数据通常会受到严重的随机噪声污染,对后续的数据处理和解释产生负面影响。常规的地震数据噪声压制方法在压制噪声时无法有效分离信号和噪声,导致数据图像细节信息丢失、产生伪纹理等问题。为提高地震图像质量,提出了基于多尺度信息感知生成对抗网络(MSIPGAN)的地震数据随机噪声压制方法。首先,设计了多尺度信息感知生成网络来去除地震数据中的随机噪声,降噪网络以传统的深度卷积神经网络为基础框架,结合并行多尺度模块、多通道信息融合模块、一致性正则化模块来改善纹理结构的准确性并保留更多细节信息;其次,构建了判别网络的判别标签数据并将其与生成网络的生成图像相结合来辅助生成网络的训练;最后,设计了一种复合损失函数指导生成网络,提升生成网络恢复图像细节信息的能力。将该方法应用于大庆油田实际工区的地震数据处理,处理结果表明,与目前的主流模型和工业软件相比,其噪声压制效果提升显著;将该方法应用于荷兰近海的海底F3地震数据的噪声压制,结果表明该方法具有较强的泛化能力。 展开更多
关键词 地震数据噪声压制 随机噪声 深度学习 生成对抗网络 地震勘探
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基于STFTGAN模型的测井曲线超分辨方法研究
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作者 韩建 贾园园 +2 位作者 郑兵 曹志民 吕婷婷 《化工自动化及仪表》 2025年第5期776-783,共8页
针对高含水阶段薄储层测井响应弱、传统超分辨方法纹理细节缺失的问题,提出了一种基于短时傅里叶变换(STFT)的生成对抗网络STFTGAN。该方法通过时频域联合学习优化高频信息重构,设计多级上采样残差模块以提取低分辨时频特征,并引入多尺... 针对高含水阶段薄储层测井响应弱、传统超分辨方法纹理细节缺失的问题,提出了一种基于短时傅里叶变换(STFT)的生成对抗网络STFTGAN。该方法通过时频域联合学习优化高频信息重构,设计多级上采样残差模块以提取低分辨时频特征,并引入多尺度判别器以强化对抗训练。此外,结合最小二乘损失、时频图损失和特征匹配损失函数,进一步提升了生成器的性能。实验结果表明,与BSI、SVM、LSTM和SRCNN方法相比,STFTGAN能够有效超分辨出测井曲线的高频细节,显著提高了薄储层识别精度,为复杂地质条件下的测井解释提供了新的解决方案。 展开更多
关键词 地球物理测井 超分辨 短时傅里叶变换 生成对抗网络 高频信息保持
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ON THE GAUSSIAN KINEMATIC FORMULA OF R.ADLER AND J.TAYLOR
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作者 Joseph H.G.Fu 《Acta Mathematica Scientia》 2025年第1期200-214,共15页
We apply methods of algebraic integral geometry to prove a special case of the Gaussian kinematic formula of Adler-Taylor.The idea,suggested already by Adler and Taylor,is to view the GKF as the limit of spherical kin... We apply methods of algebraic integral geometry to prove a special case of the Gaussian kinematic formula of Adler-Taylor.The idea,suggested already by Adler and Taylor,is to view the GKF as the limit of spherical kinematic formulas for spheres of large dimension N and curvature1/N. 展开更多
关键词 integral geometry kinematic formula probability density Gaussian density
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Lower limb coordination patterns following anterior cruciate ligament reconstruction:A longitudinal study
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作者 Cortney Armitano-Lago Elizabeth Bjornsen +5 位作者 Caroline Lisee Ashley Buck Christin Buttner Adam W.Kiefer Todd A.Schwartz Brian Pietrosimone 《Journal of Sport and Health Science》 2025年第2期126-134,共9页
Background:Changes in lower limb joint coordination have been shown to increase localized stress on knee joint soft tissue—a known precursor of osteoarthritis.While 50%of individuals who undergo anterior cruciate lig... Background:Changes in lower limb joint coordination have been shown to increase localized stress on knee joint soft tissue—a known precursor of osteoarthritis.While 50%of individuals who undergo anterior cruciate ligament reconstruction(ACLR)develop radiographic osteoarthritis,it is unclear how underlying joint coordination during gait changes post-ACLR.The purpose of this study was twofold:to determine differences in lower limb coordination patterns during gait in ACLR individuals 2,4,and 6 months post-ACLR and to compare the coordination profiles of the ACLR participants at each timepoint post-ACLR to uninjured matched controls.Methods:We conducted a longitudinal assessment to quantify lower limb coordination at 3 timepoints post-ACLR and compared the ACLR coordination profiles to uninjured controls.Thirty-four ACLR(age=21.43±4.24 years,mean±SD;70.59%female)and 34 controls(age=21.42±3.43 years;70.59%female)participated.The ACLR group completed 3 overground gait assessments(2,4,and 6 months post-ACLR),and the controls completed one assessment,at which lower limb kinematics were collected.Cross-recurrence quantification analysis was used to characterize sagittal and frontal plane ankle-knee,ankle-hip,and knee-hip coordination dynamics.Comprehensive general linear mixed models were constructed to compare between-limb and within-limb coordination outcomes over time post-ACLR and a between-group comparison across timepoints.Results:The ACLR limb demonstrated a more"stuck"sagittal plane knee-hip coordination profile(greater trapping time(TT);p=0.004)compared bilaterally.Between groups,the ACLR participants exhibited a more predictable ankle-knee coordination pattern(percent determinism(%DET);p<0.05),stronger coupling between joints(meanline(MNLine))across all segments(p<0.05),and greater knee-hip TT(more"stuck";p<0.05)compared to the controls at each timepoint in the sagittal plane.Stronger frontal plane knee-hip joint coupling(MNLine)persisted across timepoints within the ACLR group compared to the controls(p<0.05).Conclusion:The results indicate ACLR individuals exhibit a distinct and rigid coordination pattern during gait compared to controls within6-month post-ACLR,which may have long-term implications for knee-joint health. 展开更多
关键词 Cross-recurrence quantification analysis GAIT COORDINATION OSTEOARTHRITIS Nonlinear dynamics
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Light intensity modulates plant nitrogen uptake preference:Evidence from Ligustrum compactum seedlings in simulated canopy gaps of coastal shelterbelt forests
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作者 Hongtao Xie Wei Wang +3 位作者 Binghui Bao Xiaoyu Wang Sheng‑I Yang Deliang Lu 《Journal of Forestry Research》 2025年第6期15-29,共15页
Nitrogen(N)deficiency is a critical factor limiting natural regeneration in coastal shelterbelt forests,but the influence of different N forms on seedling establishment under varying light conditions remains poorly un... Nitrogen(N)deficiency is a critical factor limiting natural regeneration in coastal shelterbelt forests,but the influence of different N forms on seedling establishment under varying light conditions remains poorly understood.This study investigated the effects of N forms and N concentrations on Ligustrum compactum seedlings under simulated canopy gap conditions using a three-factor design:N form(NO_(3)^(-)-N,NH_(4)^(+)-N,mixed N),N concentration(30 and 60 kg ha^(-1)a^(-1)),and light intensity(30%,60%,and 90%full sunlight).Results showed that N addition significantly promoted seedling growth,net photosynthesis rate,and water use efficiency;however,the effects varied among N forms and concentrations.Overall,NO_(3)^(-)-N or mixed N were more favored by L.compactum seedlings;however,the N preference was altered by light intensity and N concentration.For instance,L.compactum showed greater NO_(3)^(-)-N or mixed N preference under low and medium light intensities,while displaying more NH_(4)^(+)-N preference under high light intensity.N concentration also affected the growth and N preference of L.compactum seedlings,but the variance explained by N concentration was lower than that of light intensity.Leaf C,N,P stoichiometry exhibited stronger correlations with seedling's morphological trait plasticity than those of leaf gas exchange,and further analysis demonstrated that leaf C:P and N:P were the top two critical factors affecting seedling growth,indicating that the coordination and balance among C,N,P elements were more important in explaining the seedling growth under N addition.Therefore,our results clarified that the N preference of L.compactum seedlings could be altered by light intensity and revealed that leaf C,N,P ratios were stronger predictors than leaf gas exchange parameters for explaining the N effects on seedling performance.These findings demonstrated the mechanisms of light-N interactions affecting seedling performance,providing practical guidance for optimizing N fertilization and improving natural regeneration in canopy gaps of degraded coastal shelterbelt forests. 展开更多
关键词 Nitrogen form Light intensity Seedling performance Leaf C N P Leaf gas exchange Coastal forest
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Atmospheric and Earth System Modeling towards Coordinated Pollution Control and Climate Change Mitigation
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作者 Yuhang Wang Hongliang Zhang +2 位作者 Yang Gao Bin Zhao Peng Wang 《Frontiers of Environmental Science & Engineering》 2025年第12期317-318,共2页
The intertwined challenges of air pollution and climate change represent a critical environmental dilemma of our time.These issues are inextricably linked through shared emission sources,coupled physical and chemical ... The intertwined challenges of air pollution and climate change represent a critical environmental dilemma of our time.These issues are inextricably linked through shared emission sources,coupled physical and chemical processes,and a common solution space in the transition to a sustainable future.Advanced atmospheric and Earth system modeling is therefore an indispensable tool for developing coordinated strategies that maximize co-benefits.This special issue,“Atmospheric and Earth System Modeling towards Coordinated Pollution Control and Climate Change Mitigation,”showcases cutting-edge research that enhances our modeling capabilities to address this complex nexus.The contributions collectively advance model fidelity and integration across scales,from fundamental particle properties to regional pollution transport and climate impacts. 展开更多
关键词 earth system modeling climate change mitigation atmospheric earth system modeling air pollution developing coordinated strategies pollution control climate change atmospheric modeling
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基于NSGA-Ⅱ算法的连续管下入深度优化研究
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作者 陈义洪 翁振康 +3 位作者 许得禄 娄增 徐传友 齐昌鑫 《阀门》 2025年第7期707-712,共6页
随着油气资源开发向深井、超深井及超长水平井等复杂结构井方向发展,连续管技术在冲砂、钻磨、测井等井下作业中成为关键技术工具,但在复杂井况下,连续管易受多因素耦合作用,导致下入深度不足,制约作业效率。本文基于刚杆模型构建了连... 随着油气资源开发向深井、超深井及超长水平井等复杂结构井方向发展,连续管技术在冲砂、钻磨、测井等井下作业中成为关键技术工具,但在复杂井况下,连续管易受多因素耦合作用,导致下入深度不足,制约作业效率。本文基于刚杆模型构建了连续管极限下入深度计算模型,综合考虑摩擦系数、流体密度、连续管尺寸及牵引力的耦合作用。通过与文献中的数据对比验证了模型的准确性,并将力学模型嵌入NSGA-Ⅱ算法迭代流程。将该优化方法在某5000 m水平井中应用,结果表明,优化后的连续管参数可使极限下入深度达到5000 m,成功解决了在2990 m处下入“锁死”问题。 展开更多
关键词 NSGA-Ⅱ算法 连续管 极限下入深度 优化
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Industrial solid wastes to environmental protection materials for removal of gaseous pollutants:A review 被引量:2
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作者 Jiacheng Bao Xin Sun +5 位作者 Ping Ning Kai Li Jie Yang Fei Wang Lei Shi Maohong Fan 《Green Energy & Environment》 SCIE EI CAS 2025年第1期34-83,共50页
The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective ... The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective manner.In this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid waste.We see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be altered.The review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research fully.The suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation. 展开更多
关键词 Industrial solid waste Reaction mechanism Modification method Air pollutants
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基于IGA与增强D-S证据理论的工业过程故障检测
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作者 魏淑娟 齐咏生 +2 位作者 刘利强 李永亭 高学金 《高校化学工程学报》 北大核心 2025年第3期503-521,共19页
针对复杂工业过程数据特征提取困难,且许多故障检测方法需要提前假设数据分布类型,故障检测泛化能力弱等问题,提出一种基于信息增益自适应特征选择(IGA)方法与增强Dempster-Shafer (D-S)证据理论的工业过程故障检测算法。首先,通过决策... 针对复杂工业过程数据特征提取困难,且许多故障检测方法需要提前假设数据分布类型,故障检测泛化能力弱等问题,提出一种基于信息增益自适应特征选择(IGA)方法与增强Dempster-Shafer (D-S)证据理论的工业过程故障检测算法。首先,通过决策树计算得到信息增益,利用交叉验证设定k值,自适应选择特征个数,实现数据降维和特征提取;之后,引入三元统计量监测组实现线性故障检测,同时采用自编码器、One-class SVM方法进行非线性故障监测;最后,使用增强D-S证据理论,通过一种新的综合指标,对改进后的加权平均证据体进行融合,修正基本概率分配(BPA)参数获得融合结果,得到更为可靠的检测结果。通过冷水机组数据和田纳西-伊斯曼(Tennessee-Eastman,TE)过程数据进行验证,结果表明,IGA与增强D-S证据理论方法比单独的线性或非线性检测算法的准确率更高,鲁棒性更强,且使用场景不依赖于特定数据分布假设,适用范围灵活,可以有效应用于工业过程故障检测。 展开更多
关键词 信息增益 特征提取 证据理论 故障检测 工业过程
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3.1 Ga左右全球岩浆事件和地壳演化
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作者 边天一 孟凡超 杨飞 《地质论评》 北大核心 2025年第4期1119-1141,I0001,I0007,1142,共26页
全球克拉通90%的陆壳可能是在太古宙形成,集中在3.5~3.1 Ga、2.8~2.7 Ga、2.6~2.5 Ga 3个阶段,2.8~2.7 Ga和晚期2.6~2.5 Ga时期的岩石保留较多,地壳增生与改造机制研究较多,受样品稀少限制,3.0 Ga之前的岩浆事件与陆壳形成演化研究相对... 全球克拉通90%的陆壳可能是在太古宙形成,集中在3.5~3.1 Ga、2.8~2.7 Ga、2.6~2.5 Ga 3个阶段,2.8~2.7 Ga和晚期2.6~2.5 Ga时期的岩石保留较多,地壳增生与改造机制研究较多,受样品稀少限制,3.0 Ga之前的岩浆事件与陆壳形成演化研究相对薄弱,早前寒武纪岩浆事件与地壳增生方式仍存在争议。本文系统总结了全球中太古代(主要为3.2~3.0 Ga期间)岩石的锆石年龄、岩石类型、全岩地球化学和锆石Lu—Hf—O同位素特征。主要认识包括:①3.2~3.0 Ga时期岩石在全球各大洲均有分布,现今主要集中在北半球,而南半球的数量相对较少;②岩石的锆石年龄峰值集中在约3.05 Ga和约3.15 Ga两个时期;③岩石的主要岩性为英云闪长岩和奥长花岗岩,具有过铝质的特征,不同地区呈现出不同的岩石组合,展现出一定的地区独特性;④不同地区岩石锆石的ε_(Hf)(t)值表现出明显差异,反映了岩石起源和演化历史的差异性。大部分锆石的δ^(18)O值与地幔熔体处于平衡状态,也有部分锆石的δ^(18)O值较高,可达+8.93‰,暗示岩石源区经历了一定的低温蚀变或地壳物质的混染;⑤岩石呈现轻稀土元素富集、重稀土元素亏损的右倾模式,铕元素异常明显。整体上Th、U、K、Pb等元素相对富集,而Nb、Ta、P、Sm、Ti等元素相对亏损。综合研究表明:①3.1 Ga左右TTG岩石可能由经历低温蚀变的玄武质岩石部分熔融形成。Hf同位素特征显示,该时期玄武质岩石多数为3.3 Ga左右时期由轻度亏损的地幔部分熔融形成。②中太古代早期(主要为3.2~3.0 Ga期间)发生了一次全球性质的岩浆活动和地壳增长事件,峰值期在约3.05 Ga和约3.15 Ga。③类似于现代板块运动的构造体制在中太古代已经启动。 展开更多
关键词 中太古代 地壳增生 岩浆事件 TTG岩石
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5DGWO-GAN:A Novel Five-Dimensional Gray Wolf Optimizer for Generative Adversarial Network-Enabled Intrusion Detection in IoT Systems
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作者 Sarvenaz Sadat Khatami Mehrdad Shoeibi +2 位作者 Anita Ershadi Oskouei Diego Martín Maral Keramat Dashliboroun 《Computers, Materials & Continua》 SCIE EI 2025年第1期881-911,共31页
The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by... The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by these interconnected devices,robust anomaly detection mechanisms are essential.Anomaly detection in this dynamic environment necessitates methods that can accurately distinguish between normal and anomalous behavior by learning intricate patterns.This paper presents a novel approach utilizing generative adversarial networks(GANs)for anomaly detection in IoT systems.However,optimizing GANs involves tuning hyper-parameters such as learning rate,batch size,and optimization algorithms,which can be challenging due to the non-convex nature of GAN loss functions.To address this,we propose a five-dimensional Gray wolf optimizer(5DGWO)to optimize GAN hyper-parameters.The 5DGWO introduces two new types of wolves:gamma(γ)for improved exploitation and convergence,and theta(θ)for enhanced exploration and escaping local minima.The proposed system framework comprises four key stages:1)preprocessing,2)generative model training,3)autoencoder(AE)training,and 4)predictive model training.The generative models are utilized to assist the AE training,and the final predictive models(including convolutional neural network(CNN),deep belief network(DBN),recurrent neural network(RNN),random forest(RF),and extreme gradient boosting(XGBoost))are trained using the generated data and AE-encoded features.We evaluated the system on three benchmark datasets:NSL-KDD,UNSW-NB15,and IoT-23.Experiments conducted on diverse IoT datasets show that our method outperforms existing anomaly detection strategies and significantly reduces false positives.The 5DGWO-GAN-CNNAE exhibits superior performance in various metrics,including accuracy,recall,precision,root mean square error(RMSE),and convergence trend.The proposed 5DGWO-GAN-CNNAE achieved the lowest RMSE values across the NSL-KDD,UNSW-NB15,and IoT-23 datasets,with values of 0.24,1.10,and 0.09,respectively.Additionally,it attained the highest accuracy,ranging from 94%to 100%.These results suggest a promising direction for future IoT security frameworks,offering a scalable and efficient solution to safeguard against evolving cyber threats. 展开更多
关键词 Internet of things intrusion detection generative adversarial networks five-dimensional binary gray wolf optimizer deep learning
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Metastatic pattern in esophageal and gastric cancer:Influenced by site and histology 被引量:17
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作者 Moniek HP Verstegen Mitchell Harker +5 位作者 Carlijn van de Water Jolanda van Dieren Niek Hugen Iris D Nagtegaal Camiel Rosman Rachel S van der Post 《World Journal of Gastroenterology》 SCIE CAS 2020年第39期6037-6046,共10页
BACKGROUND Detailed information on metastatic patterns in of patients with esophageal and gastric cancer is limited.Early recognition of metastases is important to avoid futile locoregional treatments.Furthermore,know... BACKGROUND Detailed information on metastatic patterns in of patients with esophageal and gastric cancer is limited.Early recognition of metastases is important to avoid futile locoregional treatments.Furthermore,knowledge on metastatic patterns is necessary for further development of personalized treatment modalities.AIM To gain insight into the metastatic pattern of gastroesophageal cancer.METHODS A nationwide retrospective autopsy study of 3876 patients with adenocarcinoma(AC)or squamous cell carcinoma(SCC)of the esophagus or stomach between 1990 and 2017 was performed.Only patient with metastases were included for analysis.The metastatic pattern was analyzed according to the primary tumor location and histological subtype.RESULTS Metastatic disease was found in 268 esophageal and 331 gastric cancer patients.In esophageal cancer,the most common metastatic locations were liver(56%),distant lymph nodes(53%)and lung(50%).Esophageal AC showed more frequently metastases to the peritoneum and bone compared with esophageal SCC.In gastric cancer,the most common metastatic locations were distant lymph nodes(56%),liver(53%)and peritoneum(51%).Intestinal-type AC of the stomach showed metastases to the liver more frequently,whereas metastases to the bone,female reproductive organs and colorectum were observed more frequently in diffuse-type gastric AC.CONCLUSION This study showed differences in metastatic patterns of patients with esophageal and gastric cancer according to the primary tumor location and histological subtype. 展开更多
关键词 Esophageal cancer Gastric cancer METASTASES HISTOLOGY Gastroesophageal junction ADENOCARCINOMA Carcinoma Squamous cell
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Roux-en-Y versus BillrothⅠreconstruction after distal gastrectomy for gastric cancer:A meta-analysis 被引量:36
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作者 Jun-Jie Xiong Kiran Altaf +8 位作者 Muhammad A Javed Quentin M Nunes Wei Huang Gang Mai Chun-Lu Tan Rajarshi Mukherjee Robert Sutton Wei-Ming Hu Xu-Bao Liu 《World Journal of Gastroenterology》 SCIE CAS 2013年第7期1124-1134,共11页
AIM: To conduct a meta-analysis to compare Roux-en-Y (R-Y) gastrojejunostomy with gastroduodenal Billroth?I?(B-I) anastomosis after distal gastrectomy (DG) for gastric cancer.METHODS: A literature search was performed... AIM: To conduct a meta-analysis to compare Roux-en-Y (R-Y) gastrojejunostomy with gastroduodenal Billroth?I?(B-I) anastomosis after distal gastrectomy (DG) for gastric cancer.METHODS: A literature search was performed to identify studies comparing R-Y with B-I?after DG for gastric cancer from January 1990 to November 2012 in Medline, Embase, Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials in The Cochrane Library. Pooled odds ratios (OR) or weighted mean differences (WMD) with 95%CI were calculated using either ?xed or random effects model. Operative outcomes such as operation time, intraoperative blood loss and postoperative outcomes such as anastomotic leakage and stricture, bile re?ux, remnant gastritis, re?ux esophagitis, dumping symptoms, delayed gastric emptying and hospital stay were the main outcomes assessed. Meta-analyses were performed using RevMan 5.0 software (Cochrane library).RESULTS: Four randomized controlled trials (RCTs) and 9 non-randomized observational clinical studies (OCS) involving 478 and 1402 patients respectively were included. Meta-analysis of RCTs revealed that R-Y reconstruction was associated with a reduced bile re?ux (OR 0.04, 95%CI: 0.01, 0.14; P < 0.00?001) and remnant gastritis (OR 0.43, 95%CI: 0.28, 0.66; P = 0.0001), however needing a longer operation time (WMD 40.02, 95%CI: 13.93, 66.11; P = 0.003). Meta-analysis of OCS also revealed R-Y reconstruction had a lower incidence of bile re?ux (OR 0.21, 95%CI: 0.08, 0.54; P = 0.001), remnant gastritis (OR 0.18, 95%CI: 0.11, 0.29; P < 0.00?001) and re?ux esophagitis (OR 0.48, 95%CI: 0.26, 0.89; P = 0.02). However, this reconstruction method was found to be associated with a longer operation time (WMD 31.30, 95%CI: 12.99, 49.60; P = 0.0008).CONCLUSION: This systematic review point towards some clinical advantages that are rendered by R-Y compared to B-I?reconstruction post DG. However there is a need for further adequately powered, well-designed RCTs comparing the same. 展开更多
关键词 Gastric cancer Distal gastrectomy ROUX-EN-Y Billroth I RECONSTRUCTION META-ANALYSIS
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