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GNSS time series analysis of the crustal movement network of China:Detecting the optimal order of the polynomial term and its effect on the deterministic model
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作者 Shuguang Wu Hua Ouyang +3 位作者 Houpu Li Zhao Li Haiyang Li Yuefan He 《Geodesy and Geodynamics》 2025年第4期378-386,共9页
GNSS time series analysis provides an effective method for research on the earth's surface deformation,and it can be divided into two parts,deterministic models and stochastic models.The former part can be achieve... GNSS time series analysis provides an effective method for research on the earth's surface deformation,and it can be divided into two parts,deterministic models and stochastic models.The former part can be achieved by several parameters,such as polynomial terms,periodic terms,offsets,and post-seismic models.The latter contains some stochastic noises,which can be affected by detecting the former parameters.If there are not enough parameters assumed,modeling errors will occur and adversely affect the analysis results.In this study,we propose a processing strategy in which the commonly-used 1-order of the polynomial term can be replaced with different orders for better fitting GNSS time series of the Crustal Movement Network of China(CMONOC)stations.Initially,we use the Bayesian Information Criterion(BIC)to identify the best order within the range of 1-4 during the fitting process using the white noise plus power-law noise(WN+PL)model.Then,we compare the 1-order and the optimal order on the effect of deterministic models in GNSS time series,including the velocity and its uncertainty,amplitudes,and initial phases of the annual signals.The results indicate that the first-order polynomial in the GNSS time series is not the primary factor.The root mean square(RMS)reduction rates of almost all station components are positive,which means the new fitting of optimal-order polynomial helps to reduce the RMS of residual series.Most stations maintain the velocity difference(VD)within ±1 mm/yr,with percentages of 85.6%,81.9%and 63.4%in the North,East,and Up components,respectively.As for annual signals,the numbers of amplitude difference(AD)remained at ±0.2 mm are 242,239,and 200 in three components,accounting for 99.6%,98.4%,and 82.3%,respectively.This finding reminds us that the detection of the optimal-order polynomial is necessary when we aim to acquire an accurate understanding of the crustal movement features. 展开更多
关键词 GNSS time series analysis CMONOC Optimal polynomial order Deterministic model
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Prescribed-Time Active Disturbance Rejection Control for Electromagnetic Formation Flight Under Model Uncertainties and Disturbances
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作者 SHEN Xixi MENG Bin HU Jiangping 《空间控制技术与应用(中英文)》 北大核心 2026年第1期94-102,共9页
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ... This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller. 展开更多
关键词 electromagnetic formation prescribed time active disturbance rejection control output feedback control
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1例坏疽性脓皮病病人基于“TIME”原则的创面护理实践
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作者 郭青 赵茜 +1 位作者 冯晓琳 栾红 《全科护理》 2026年第2期386-389,共4页
总结1例坏疽性脓皮病病人应用“TIME”原则的创面护理经验,基于“TIME”原则结合系统药物治疗及多维度护理干预,实施分阶段创面护理。经过50 d系统治疗及针对性护理,病人溃疡面积显著缩小,疼痛数字评分(NRS)由8分降至2分,创面基底肉芽... 总结1例坏疽性脓皮病病人应用“TIME”原则的创面护理经验,基于“TIME”原则结合系统药物治疗及多维度护理干预,实施分阶段创面护理。经过50 d系统治疗及针对性护理,病人溃疡面积显著缩小,疼痛数字评分(NRS)由8分降至2分,创面基底肉芽组织增生良好,出院33 d后随访病情稳定,伤口愈合良好。 展开更多
关键词 坏疽性脓皮病 time”原则 创面护理 伤口感染
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Calculation method for cut blasting millisecond-delay time in a viscoelastic rock mass
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作者 Zhao Fengze Chen Ming +3 位作者 Li Kanggui Lu Wenbo Wang Yang Ye Zhiwei 《Earthquake Engineering and Engineering Vibration》 2026年第1期123-139,共17页
This research is focused on the calculation of a reasonable detonator delay time for realizing cut blast vibration control.First,the viscoelastic rock mass parameters corresponding to the engineering rock mass quality... This research is focused on the calculation of a reasonable detonator delay time for realizing cut blast vibration control.First,the viscoelastic rock mass parameters corresponding to the engineering rock mass quality classification were determined based on wave theory of Kelvin medium.Then,a calculation model was obtained for the millisecond-delay cut blast vibration in Kelvin media using the Starfield charge superposition principle.Further,the influence of the delay time on the cut blast vibration was quantitatively analyzed and a method for calculating the reasonable cut blasting millisecond delay time is proposed according to the principle of dimensional analysis.Finally,field tests were used to verify the applicability of the method.The results show that 5 ms to 20 ms is a better detonator delay time range and cut blasting vibration can be effectively controlled using the delay time calculated by the calculation model described in this paper. 展开更多
关键词 cut blasting VISCOELASTIC vibration control millisecond-delay time
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Similarity transformation-based modeling of the thermally-radiative tetra-hybrid Casson nanofluid flow over a nonlinear stretching sheet using the Clique polynomial collocation method
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作者 U.L.MANIKANTA K.J.GOWTHAM +1 位作者 B.J.GIREESHA P.VENKATESH 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期185-202,共18页
The flow of a tetra-hybrid Casson nanofluid(Al_(2)O_(3)-CuO-TiO_(2)-Ag/H_(2)O)over a nonlinear stretching sheet is investigated.The Buongiorno model is used to account for thermophoresis and Brownian motion,while ther... The flow of a tetra-hybrid Casson nanofluid(Al_(2)O_(3)-CuO-TiO_(2)-Ag/H_(2)O)over a nonlinear stretching sheet is investigated.The Buongiorno model is used to account for thermophoresis and Brownian motion,while thermal radiation is incorporated to examine its influence on the thermal boundary layer.The governing partial differential equations(PDEs)are reduced to a system of nonlinear ordinary differential equations(ODEs)with fully non-dimensional similarity transformations involving all independent variables.To solve the obtained highly nonlinear system of differential equations,a novel Clique polynomial collocation method is applied.The analysis focuses on the effects of the Casson parameter,power index,radiation parameter,thermophoresis parameter,Brownian motion parameter,and Lewis number.The key findings show that thermal radiation intensifies the thermal boundary layer,the Casson parameter reduces the velocity,and the Lewis number suppresses the concentration with direct relevance to polymer processing,coating flows,electronic cooling,and biomedical applications. 展开更多
关键词 similarity transformation nonlinear stretching sheet Casson parameter tetra-hybrid nanofluid thermal radiation Clique polynomial collocation method
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Deciphering the genetic regulation of flowering time in rapeseed for early-maturation breeding
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作者 Minghao Zhang Wei Chang +16 位作者 Ruicheng Hu Yuxuan Ruan Xiaodong Li Yonghai Fan Boyu Meng Shengting Li Mingchao Qian Yuling Chen Yuanyi Mao Daifei Song Haikun Yang Luxiang Niu Guangyuan Cao Zhixia Deng Zhixuan Qin Hui Wang Kun Lu 《Journal of Genetics and Genomics》 2026年第1期16-27,共12页
Flowering time is a critical agronomic trait with a profound effect on the productivity and adaptabillity of rapeseed(Brassica napus L.).Strategically advancing flowering time can reduce the risk of yield losses due t... Flowering time is a critical agronomic trait with a profound effect on the productivity and adaptabillity of rapeseed(Brassica napus L.).Strategically advancing flowering time can reduce the risk of yield losses due to extreme climatic conditions and facilitate the cultivation of subsequent crops on the same land,thereby enhancing overall agricultural efficiency.In this review,we synthesize current information on flowering time regulation in rapeseed through an integrated analysis of its genetic,hormonal,and environmental dimensions,emphasizing their crosstalk and implications for yield.We consolidate multi-omics evidence from population genetics,functional genomics,and systems biology to create a haplotype-based framework that overcomes the trade-off between flowering time and yield,providing support for the precision breeding of early-maturing cultivars.The insights presented here could inform future research on flowering time regulation and guide strategies for increasing rapeseed productivity. 展开更多
关键词 Brassica napus Early maturation Flowering time Genetic regulation YIELD
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基于TimeGAN-LSTM-MLP的钻井溢流智能监测模型
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作者 彭炽 万兴 +3 位作者 林铁军 李庆峰 苏昱 杨赟 《钻采工艺》 北大核心 2026年第1期171-183,共13页
由于钻井现场实钻溢流数据较少,导致智能溢流监测模型训练困难,准确度和泛化能力较差,为此,文章提出一种基于时间序列生成对抗网络(TimeGAN)的溢流时序数据扩增方法,通过真实溢流数据生成人工溢流样本,并利用长短期记忆神经网络(LSTM)... 由于钻井现场实钻溢流数据较少,导致智能溢流监测模型训练困难,准确度和泛化能力较差,为此,文章提出一种基于时间序列生成对抗网络(TimeGAN)的溢流时序数据扩增方法,通过真实溢流数据生成人工溢流样本,并利用长短期记忆神经网络(LSTM)提取井口多元时序特征,多层感知机(MLP)完成分类任务,构建溢流智能监测模型。利用四川盆地深层页岩气井实钻数据,分析了不平衡数据处理技术及样本不平衡比对模型监测性能的影响,同时通过消融实验探讨各模块对溢流识别的贡献。结果表明,TimeGAN优于其他数据平衡处理技术,模型在样本不平衡比为1时的准确率、召回率、精确率及F值最高,表明保证样本类别平衡是构建可靠溢流监测模型的关键。经现场验证,模型在四川某页岩气井成功实现高效准确的实钻溢流监测,展现出良好的应用潜力。 展开更多
关键词 timeGAN 溢流监测 机器学习 时间序列 不平衡样本
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A Case of Severe Trauma with Iliac Vascular Injury was Treated using a Time-Based Chain Approach
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作者 Yazheng Shen Lining He +3 位作者 Huifeng Tang Zhiyong Shi Zhen He Ke Guo 《Journal of Clinical and Nursing Research》 2026年第1期380-386,共7页
Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based c... Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based chain rescue is crucial in managing severe trauma.A patient with chest and abdominal injuries and hemorrhagic shock was transferred from an ambulance to our hospital.Our trauma team-initiated pre-hospital first aid,utilized an emergency green channel,and conducted rapid ultrasound,collaborating across disciplines.The patient eventually recovered and was discharged. 展开更多
关键词 Severe trauma Hemorrhagic shock time point of trauma Chain-type treatment
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes Experimental data Theoretical model Delay time Wave superposition
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LinguTimeX a Framework for Multilingual CTC Detection Using Explainable AI and Natural Language Processing
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作者 Omar Darwish Shorouq Al-Eidi +4 位作者 Abdallah Al-Shorman Majdi Maabreh Anas Alsobeh Plamen Zahariev Yahya Tashtoush 《Computers, Materials & Continua》 2026年第1期2231-2251,共21页
Covert timing channels(CTC)exploit network resources to establish hidden communication pathways,posing signi cant risks to data security and policy compliance.erefore,detecting such hidden and dangerous threats remain... Covert timing channels(CTC)exploit network resources to establish hidden communication pathways,posing signi cant risks to data security and policy compliance.erefore,detecting such hidden and dangerous threats remains one of the security challenges. is paper proposes LinguTimeX,a new framework that combines natural language processing with arti cial intelligence,along with explainable Arti cial Intelligence(AI)not only to detect CTC but also to provide insights into the decision process.LinguTimeX performs multidimensional feature extraction by fusing linguistic attributes with temporal network patterns to identify covert channels precisely.LinguTimeX demonstrates strong e ectiveness in detecting CTC across multiple languages;namely English,Arabic,and Chinese.Speci cally,the LSTM and RNN models achieved F1 scores of 90%on the English dataset,89%on the Arabic dataset,and 88%on the Chinese dataset,showcasing their superior performance and ability to generalize across multiple languages. is highlights their robustness in detecting CTCs within security systems,regardless of the language or cultural context of the data.In contrast,the DeepForest model produced F1-scores ranging from 86%to 87%across the same datasets,further con rming its e ectiveness in CTC detection.Although other algorithms also showed reasonable accuracy,the LSTM and RNN models consistently outperformed them in multilingual settings,suggesting that deep learning models might be better suited for this particular problem. 展开更多
关键词 Arabic language Chinese language covert timing channel CYBERSECURITY deep learning English language language processing machine learning
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Improved simulated annealing algorithm for UAV path planning with uncertain flight time
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作者 LI Xiaoduo LUO He +1 位作者 WANG Guoqiang YIN Youlong 《Journal of Systems Engineering and Electronics》 2026年第1期272-286,共15页
Efficient multiple unmanned aerial vehicles(UAVs)path planning is crucial for improving mission completion efficiency in UAV operations.However,during the actual flight of UAVs,the flight time between nodes is always ... Efficient multiple unmanned aerial vehicles(UAVs)path planning is crucial for improving mission completion efficiency in UAV operations.However,during the actual flight of UAVs,the flight time between nodes is always influenced by external factors,making the original path planning solution ineffective.In this paper,the multi-depot multi-UAV path planning problem with uncertain flight time is modeled as a robust optimization model with a budget uncertainty set.Then,the robust optimization model is transformed into a mixed integer linear programming model by the strong duality theorem,which makes the problem easy to solve.To effectively solve large-scale instances,a simulated annealing algorithm with a robust feasibility check(SA-RFC)is developed.The numerical experiment shows that the SA-RFC can find high-quality solutions within a few seconds.Moreover,the effect of the task location distribution,depot counts,and variations in robustness parameters on the robust optimization solution is analyzed by using Monte Carlo experiments.The results demonstrate that the proposed robust model can effectively reduce the risk of the UAV failing to return to the depot without significantly compromising the profit. 展开更多
关键词 unmanned aerial vehicle(UAV)path planning uncertain flight time robust optimization simulated annealing
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Blue and White Harmony Time-Honored Craft's Modern-Day Resurgence
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作者 Pei Zhaoyue 《Women of China》 2026年第3期56-59,共4页
Blue calico,which dates back more than 800 years,is a traditional blue-and-white-printed fabric in Nantong,a city in East China's Jiangsu Province.Blue calico is renowned for its simple,yet elegant,patterns,the st... Blue calico,which dates back more than 800 years,is a traditional blue-and-white-printed fabric in Nantong,a city in East China's Jiangsu Province.Blue calico is renowned for its simple,yet elegant,patterns,the striking beauty of its blue-and-white harmony and,especially,for its printing and dyeing being performed by hand. 展开更多
关键词 blue white modern day resurgence printing dyeing time honored crafts blue calicowhich blue calico hand printing dyeing
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ENGRAVING TIMES WITH SCULPTURES
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作者 Yang Ning 《Women of China》 2026年第3期52-55,共4页
Chinese-German sculptor Zhou Xiaoping has been traveling between China and Germany,creating sculptures,since 2003.She has created more than 80 large,urban sculptures,each of which has become a vivid carrier of urban m... Chinese-German sculptor Zhou Xiaoping has been traveling between China and Germany,creating sculptures,since 2003.She has created more than 80 large,urban sculptures,each of which has become a vivid carrier of urban memories.During the past decade,she has focused on creating freeform sculptures,and she has launched a global,cross-disciplinary-artist-collaboration project,which has involved the preservation of archives for contemporary artistic creation. 展开更多
关键词 freeform sculptures sculptures freeform sculpturesand archive preservation artist collaboration engraving times urban memories preservation archives contemporary artistic creation
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Learning from Scarcity:A Review of Deep Learning Strategies for Cold-Start Energy Time-Series Forecasting
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作者 Jihoon Moon 《Computer Modeling in Engineering & Sciences》 2026年第1期26-76,共51页
Predicting the behavior of renewable energy systems requires models capable of generating accurate forecasts from limited historical data,a challenge that becomes especially pronounced when commissioning new facil-iti... Predicting the behavior of renewable energy systems requires models capable of generating accurate forecasts from limited historical data,a challenge that becomes especially pronounced when commissioning new facil-ities where operational records are scarce.This review aims to synthesize recent progress in data-efficient deep learning approaches for addressing such“cold-start”forecasting problems.It primarily covers three interrelated domains—solar photovoltaic(PV),wind power,and electrical load forecasting—where data scarcity and operational variability are most critical,while also including representative studies on hydropower and carbon emission prediction to provide a broader systems perspective.To this end,we examined trends from over 150 predominantly peer-reviewed studies published between 2019 and mid-2025,highlighting advances in zero-shot and few-shot meta-learning frameworks that enable rapid model adaptation with minimal labeled data.Moreover,transfer learning approaches combined with spatiotemporal graph neural networks have been employed to transfer knowledge from existing energy assets to new,data-sparse environments,effectively capturing hidden dependencies among geographic features,meteorological dynamics,and grid structures.Synthetic data generation has further proven valuable for expanding training samples and mitigating overfitting in cold-start scenarios.In addition,large language models and explainable artificial intelligence(XAI)—notably conversational XAI systems—have been used to interpret and communicate complex model behaviors in accessible terms,fostering operator trust from the earliest deployment stages.By consolidating methodological advances,unresolved challenges,and open-source resources,this review provides a coherent overview of deep learning strategies that can shorten the data-sparse ramp-up period of new energy infrastructures and accelerate the transition toward resilient,low-carbon electricity grids. 展开更多
关键词 Cold-start forecasting zero-shot learning few-shot meta-learning transfer learning spatiotemporal graph neural networks energy time series large language models explainable artificial intelligence(XAI)
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基于TimeVAE的1DCNN-S-Mamba组合模型光伏功率短期预测
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作者 许可证 文中 王秋杰 《热力发电》 北大核心 2026年第1期122-133,共12页
针对极端天气下光伏功率预测存在的气象响应失准、突变特征捕捉困难及数据稀缺等问题,提出一种基于模糊C均值(fuzzy C-means,FCM)、最大信息系数(maximum information coefficient,MIC)、时序变分自编码器(time variational auto-encode... 针对极端天气下光伏功率预测存在的气象响应失准、突变特征捕捉困难及数据稀缺等问题,提出一种基于模糊C均值(fuzzy C-means,FCM)、最大信息系数(maximum information coefficient,MIC)、时序变分自编码器(time variational auto-encoders,TimeVAE)、一维卷积神经网络(1D convolutional neural network,1DCNN)和simple-Mamba(S-Mamba)的组合功率预测模型。首先,通过气象特征结合FCM聚类将天气划分为晴天、多云、降雪和降雨4类;然后,结合MIC筛选出最佳气象特征子集,同时针对极端天气样本匮乏问题,采用Time VAE进行数据生成,利用其分解式重构机制生成仿真数据;最后,使用1DCNN-S-Mamba组合模型通过局部卷积捕获短时突变特征,结合双向状态空间建模实现长程依赖解析进行预测。实验结果表明,该模型提升了复杂天气下光伏功率预测的时效性与准确性。相较于S-Mamba,所提模型平均绝对误差和均方根误差在降雪天气下分别降低了3.65%和5.10%。 展开更多
关键词 模糊聚类 时序变分自编码器 数据增强 一维卷积神经网络 S-Mamba
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品管圈在提高拔牙术前Time-out程序正确执行率的应用
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作者 游迪迪 叶芳平 +1 位作者 武丹 谷丽萍 《现代医院》 2026年第1期47-51,共5页
目的探讨品管圈活动在提高口腔门诊拔牙术前Time-out程序正确执行率的应用效果。方法成立品管圈小组,调查科室现状,采用5/3/1评分法选定“提高拔牙术前Time-out程序正确执行率”为活动主题,收集2023年6月1日—6月8日南方医科大学口腔医... 目的探讨品管圈活动在提高口腔门诊拔牙术前Time-out程序正确执行率的应用效果。方法成立品管圈小组,调查科室现状,采用5/3/1评分法选定“提高拔牙术前Time-out程序正确执行率”为活动主题,收集2023年6月1日—6月8日南方医科大学口腔医院海珠广场院区口腔颌面外科拔牙术前Time-out程序正确执行情况,2023年10月12日至10月19日分析未正确执行的原因,设定改善目标,制定并实施对策。结果品管圈活动实施后,拔牙术前Time-out程序正确执行率由35.89%提升至80.81%,目标达成率和进步率分别为107.26%和125.16%。圈员的综合能力较活动前明显提升。结论品管圈活动能有效提高口腔门诊拔牙术前Time-out程序正确执行率,降低医疗风险,保障患者安全,同时增加科室成员的责任心与严谨性,促进医护协作,体现品管圈管理工具在解决临床问题中的实用价值。 展开更多
关键词 品管圈 拔牙术前的核对 time-out程序
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Local polynomial prediction method of multivariate chaotic time series and its application 被引量:1
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作者 方芬 王海燕 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期229-232,共4页
To improve the prediction accuracy of chaotic time series, a new methodformed on the basis of local polynomial prediction is proposed. The multivariate phase spacereconstruction theory is utilized to reconstruct the p... To improve the prediction accuracy of chaotic time series, a new methodformed on the basis of local polynomial prediction is proposed. The multivariate phase spacereconstruction theory is utilized to reconstruct the phase space firstly, and on its basis, apolynomial function is applied to construct the prediction model, then the parameters of the modelaccording to the data matrix built with the embedding dimensions are estimated and a one-stepprediction value is calculated. An estimate and one-step prediction value is calculated. Finally,the mean squared root statistics are used to estimate the prediction effect. The simulation resultsobtained by the Lorenz system and the prediction results of the Shanghai composite index show thatthe local polynomial prediction errors of the multivariate chaotic time series are small and itsprediction accuracy is much higher than that of the univariate chaotic time series. 展开更多
关键词 chaotic time series phase space reconstruction local polynomial prediction stock market
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Optimizing Polynomial-Time Solutions to a Network Weighted Vertex Cover Game 被引量:1
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作者 Jie Chen Kaiyi Luo +2 位作者 Changbing Tang Zhao Zhang Xiang Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期512-523,共12页
Weighted vertex cover(WVC)is one of the most important combinatorial optimization problems.In this paper,we provide a new game optimization to achieve efficiency and time of solutions for the WVC problem of weighted n... Weighted vertex cover(WVC)is one of the most important combinatorial optimization problems.In this paper,we provide a new game optimization to achieve efficiency and time of solutions for the WVC problem of weighted networks.We first model the WVC problem as a general game on weighted networks.Under the framework of a game,we newly define several cover states to describe the WVC problem.Moreover,we reveal the relationship among these cover states of the weighted network and the strict Nash equilibriums(SNEs)of the game.Then,we propose a game-based asynchronous algorithm(GAA),which can theoretically guarantee that all cover states of vertices converging in an SNE with polynomial time.Subsequently,we improve the GAA by adding 2-hop and 3-hop adjustment mechanisms,termed the improved game-based asynchronous algorithm(IGAA),in which we prove that it can obtain a better solution to the WVC problem than using a the GAA.Finally,numerical simulations demonstrate that the proposed IGAA can obtain a better approximate solution in promising computation time compared with the existing representative algorithms. 展开更多
关键词 Game-based asynchronous algorithm(GAA) game optimization polynomial time strict Nash equilibrium(SNE) weighted vertex cover(WVC)
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TIME伤口床准备联合封闭式负压引流用于食管肿瘤术后颈部吻合瘘护理
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作者 李艳 周林荣 +4 位作者 龚兰娟 叶春燕 关雪红 李桃 李翠 《医学理论与实践》 2025年第16期2841-2843,共3页
目的:在食管肿瘤术后并发颈部吻合瘘患者护理中给予TIME伤口床准备联合封闭式负压引流的干预方式,就其护理效果进行分析。方法:选取2020年7月—2023年6月我科26例食管癌术后并发吻合口瘘患者为研究对象,采用随机数字表法将患者分为观察... 目的:在食管肿瘤术后并发颈部吻合瘘患者护理中给予TIME伤口床准备联合封闭式负压引流的干预方式,就其护理效果进行分析。方法:选取2020年7月—2023年6月我科26例食管癌术后并发吻合口瘘患者为研究对象,采用随机数字表法将患者分为观察组和对照组。观察组应用TIME伤口床准备联合封闭式负压引流治疗,对照组采用常规伤口换药处理,对比两组护理成效。结果:观察组术后15d内换药次数少于对照组,颈部切口愈合时间、经口进食流质时间以及术后住院时间明显短于对照组,同时观察组的6个月内吻合口狭窄发生率、6个月并发症发生率明显低于对照组(P<0.05);干预后,两组患者的QLQ-OES18各维度评分均较干预前降低,且观察组的各维度评分均低于对照组(P<0.05);观察组的护理总有效率显著高于对照组(P<0.05)。结论:TIME伤口床准备联合封闭式负压引流应用于食管肿瘤术后并发颈部吻合瘘护理中效果显著,可以有效缩短治疗时间,提高生活质量,改善预后,建议在临床上推广应用。 展开更多
关键词 食管肿瘤术后 颈部吻合瘘 time伤口床准备 封闭式负压引流 护理效果
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Novel Stability Criteria for Linear Time-Delay Systems Using Lyapunov-Krasovskii Functionals With A Cubic Polynomial on Time-Varying Delay 被引量:9
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作者 Xian-Ming Zhang Qing-Long Han Xiaohua Ge 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第1期77-85,共9页
One of challenging issues on stability analysis of time-delay systems is how to obtain a stability criterion from a matrix-valued polynomial on a time-varying delay.The first contribution of this paper is to establish... One of challenging issues on stability analysis of time-delay systems is how to obtain a stability criterion from a matrix-valued polynomial on a time-varying delay.The first contribution of this paper is to establish a necessary and sufficient condition on a matrix-valued polynomial inequality over a certain closed interval.The degree of such a matrix-valued polynomial can be an arbitrary finite positive integer.The second contribution of this paper is to introduce a novel LyapunovKrasovskii functional,which includes a cubic polynomial on a time-varying delay,in stability analysis of time-delay systems.Based on the novel Lyapunov-Krasovskii functional and the necessary and sufficient condition on matrix-valued polynomial inequalities,two stability criteria are derived for two cases of the time-varying delay.A well-studied numerical example is given to show that the proposed stability criteria are of less conservativeness than some existing ones. 展开更多
关键词 Bessel-Legendre inequality matrix-valued polynomial inequalities stability time-varying delay time-delay systems
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