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Carreau-Extended非牛顿流体圆管层流流动的摄动解
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作者 叶俊华 雷卫明 +5 位作者 王昭华 马文军 赵磊 马建荣 史高均 孙杰 《管道技术与设备》 CAS 2024年第3期1-5,25,共6页
非牛顿流体在工业生产中应用广泛。文中基于同时包含屈服应力、时间常数和幂律指数的Carreau-Extended(简称Carreau-E)复杂流变方程及剪切应力与压降平衡关系,建立了圆管内充分发展的稳定Carreau-E流体层流管流的运动方程,并采用摄动方... 非牛顿流体在工业生产中应用广泛。文中基于同时包含屈服应力、时间常数和幂律指数的Carreau-Extended(简称Carreau-E)复杂流变方程及剪切应力与压降平衡关系,建立了圆管内充分发展的稳定Carreau-E流体层流管流的运动方程,并采用摄动方法推导出相应运动方程的一阶渐近解,获得了不同类型流体管流的速度分布以及压力梯度、流核宽度、屈服应力和时间常数对Carreau-E流体管流流场分布的影响规律,该研究对Carreau-E流体及其他复杂非牛顿流体管流特性研究具有参考价值。 展开更多
关键词 Carreau-extended流体 层流管流 流场 摄动解
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The Extended Hybrid Carrier-Based Multiple Access Technology for High Mobility Scenarios 被引量:1
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作者 Ge Song Xiaojie Fang Xuejun Sha 《China Communications》 SCIE CSCD 2024年第1期53-68,共16页
The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communicatio... The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communication.By employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution design.The implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is provided.In addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access scheme.The proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility environments.Simulation results have verified the feasibility and advantages of the proposed scheme.Compared with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications. 展开更多
关键词 extended hybrid carrier system high mo-Received:Jun.09 2023 Revised:Nov.20 2023 Editor:Yuanwei Liu bility communications multiple access
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Extended context-based semantic communication system for text transmission
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作者 Yueling Liu Shengteng Jiang +5 位作者 Yichi Zhang Kuo Cao Li Zhou Boon-Chong Seet Haitao Zhao Jibo Wei 《Digital Communications and Networks》 SCIE CSCD 2024年第3期568-576,共9页
Context information is significant for semantic extraction and recovery of messages in semantic communication.However,context information is not fully utilized in the existing semantic communication systems since re-l... Context information is significant for semantic extraction and recovery of messages in semantic communication.However,context information is not fully utilized in the existing semantic communication systems since re-lationships between sentences are often ignored.In this paper,we propose an Extended Context-based Semantic Communication(ECSC)system for text transmission,in which context information within and between sentences is explored for semantic representation and recovery.At the encoder,self-attention and segment-level relative attention are used to extract context information within and between sentences,respectively.In addition,a gate mechanism is adopted at the encoder to incorporate the context information from different ranges.At the decoder,Transformer-XL is introduced to obtain more semantic information from the historical communication processes for semantic recovery.Simulation results show the effectiveness of our proposed model in improving the semantic accuracy between transmitted and recovered messages under various channel conditions. 展开更多
关键词 semantic communication extended context Transformer-XL
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Multiple Matching Attenuation Based on Curvelet Domain Extended Filtering
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作者 HUA Qingfeng CHEN Zhang +6 位作者 HE Huili TAN Jun CHEN Haifeng LI Guanbao SONG Peng ZHAO Bo JIANG Xiuping 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期924-932,共9页
The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet doma... The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet domain.Firstly,the method uses the predicted multiple data to generate the Hilbert transform records,time derivative records and time derivative records of Hilbert transform.Then,the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is performed.Finally,the attenuation results are transformed back into the time-space domain.Tests on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries well.Furthermore,it has higher accuracy in eliminating multiple reflections,which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method. 展开更多
关键词 multiple matching attenuation curvelet domain extended filtering
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Occurrence of K1 and K2 serotypes and genotypic characteristics of extended spectrumβ-lactamases-producing Klebsiella pneumoniae isolated from selected hospitals in Malaysia
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作者 Nurul Syazrah Anuar Hazmin Hazman +5 位作者 Sharven Raj Jeyakumar Mohd Nasir Mohd Desa Hasni Idayu Saidi Siti Norbaya Masri Nur Afiza Aziz Nurshahira Sulaiman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期30-38,共9页
Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selecte... Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selected hospitals in Malaysia.Methods:A total of 192 K.pneumoniae isolates were collected and subjected to antibiotic susceptibility,hypermucoviscosity test and multiplex PCR to detect the presence of K1-and K2-serotype associated genes.Multilocus sequence typing(MLST)was performed on ESBL-producing K.pneumoniae isolates presented with K1 and K2 serotypes,followed by phylogenetic analysis.Results:A total of 87 out of 192(45.3%)of the K.pneumoniae isolates collected were ESBL producers.However,only 8.3%(16/192)and 10.9%(21/192)of the total isolates were detected to carry K1-and K2-serotype associated genes,respectively.Statistical analysis showed that K1 and K2 capsular serotypes were not significantly associated with ESBL phenotype(P=0.196).However,they were significantly associated with hypervirulent,as demonstrated by the positive string test(P<0.001).MLST analysis revealed that ST23 as the predominant sequence type(ST)in the K1 serotype,while the ST in the K2 serotype is more diverse.Conclusions:Although the occurrence of ESBL-producing isolates among the hypervirulent strains was low,their coexistence warrants the need for continuous surveillance.MLST showed that these isolates were genetically heterogeneous. 展开更多
关键词 extended spectrumβ-lactamases Klebsiella pneumoniae Capsular serotypes GENOTYPIC
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Analysis of Extended Fisher-Kolmogorov Equation in 2D Utilizing the Generalized Finite Difference Method with Supplementary Nodes
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作者 Bingrui Ju Wenxiang Sun +1 位作者 Wenzhen Qu Yan Gu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期267-280,共14页
In this study,we propose an efficient numerical framework to attain the solution of the extended Fisher-Kolmogorov(EFK)problem.The temporal derivative in the EFK equation is approximated by utilizing the Crank-Nicolso... In this study,we propose an efficient numerical framework to attain the solution of the extended Fisher-Kolmogorov(EFK)problem.The temporal derivative in the EFK equation is approximated by utilizing the Crank-Nicolson scheme.Following temporal discretization,the generalized finite difference method(GFDM)with supplementary nodes is utilized to address the nonlinear boundary value problems at each time node.These supplementary nodes are distributed along the boundary to match the number of boundary nodes.By incorporating supplementary nodes,the resulting nonlinear algebraic equations can effectively satisfy the governing equation and boundary conditions of the EFK equation.To demonstrate the efficacy of our approach,we present three numerical examples showcasing its performance in solving this nonlinear problem. 展开更多
关键词 Generalized finite difference method nonlinear extended Fisher-Kolmogorov equation Crank-Nicolson scheme
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Extended reading板块教学设计
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作者 施晓明 《江苏教育》 2024年第15期35-38,共4页
根据《普通高中英语课程标准(2017年版2020修订)》(以下简称“新课标”),教师应引导学生广泛阅读,提升阅读能力,丰富语言、人文和科学知识,并拓展思维,增强审美、鉴赏和评价能力。广义的拓展阅读可在课堂内外开展;狭义的拓展阅读指基于... 根据《普通高中英语课程标准(2017年版2020修订)》(以下简称“新课标”),教师应引导学生广泛阅读,提升阅读能力,丰富语言、人文和科学知识,并拓展思维,增强审美、鉴赏和评价能力。广义的拓展阅读可在课堂内外开展;狭义的拓展阅读指基于单元主题,在课堂内进行的主题式拓展阅读,是对教材主阅读板块内容的延伸和内涵的拓展。[1]作为拓展阅读的素材,非故事类文本有助于学生拓宽知识面、增进对世界的认识。 展开更多
关键词 高中英语 extended reading板块 深度学习 非故事类文本
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An extended state observer with adjustable bandwidth for measurement noise
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作者 ZHANG Shihua QI Xiaohui YANG Sen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期233-241,共9页
In this paper,a bandwidth-adjustable extended state observer(ABESO)is proposed for the systems with measurement noise.It is known that increasing the bandwidth of the observer improves the tracking speed but tolerates... In this paper,a bandwidth-adjustable extended state observer(ABESO)is proposed for the systems with measurement noise.It is known that increasing the bandwidth of the observer improves the tracking speed but tolerates noise,which conflicts with observation accuracy.Therefore,we introduce a bandwidth scaling factor such that ABESO is formulated to a 2-degree-of-freedom system.The observer gain is determined and the bandwidth scaling factor adjusts the bandwidth according to the tracking error.When the tracking error decreases,the bandwidth decreases to suppress the noise,otherwise the bandwidth does not change.It is proven that the error dynamics are bounded and converge in finite time.The relationship between the upper bound of the estimation error and the scaling factor is given.When the scaling factor is less than 1,the ABESO has higher estimation accuracy than the linear extended state observer(LESO).Simulations of an uncertain nonlinear system with compound disturbances show that the proposed ABESO can successfully estimate the total disturbance in noisy environments.The mean error of total disturbance of ABESO is 15.28% lower than that of LESO. 展开更多
关键词 extended state observer(ESO) boundedness and convergence adjustable bandwidth measurement noise
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WSN Mobile Target Tracking Based on Improved Snake-Extended Kalman Filtering Algorithm
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作者 Duo Peng Kun Xie Mingshuo Liu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期28-40,共13页
A wireless sensor network mobile target tracking algorithm(ISO-EKF)based on improved snake optimization algorithm(ISO)is proposed to address the difficulty of estimating initial values when using extended Kalman filte... A wireless sensor network mobile target tracking algorithm(ISO-EKF)based on improved snake optimization algorithm(ISO)is proposed to address the difficulty of estimating initial values when using extended Kalman filtering to solve the state of nonlinear mobile target tracking.First,the steps of extended Kalman filtering(EKF)are introduced.Second,the ISO is used to adjust the parameters of the EKF in real time to adapt to the current motion state of the mobile target.Finally,the effectiveness of the algorithm is demonstrated through filtering and tracking using the constant velocity circular motion model(CM).Under the specified conditions,the position and velocity mean square error curves are compared among the snake optimizer(SO)-EKF algorithm,EKF algorithm,and the proposed algorithm.The comparison shows that the proposed algorithm reduces the root mean square error of position by 52%and 41%compared to the SOEKF algorithm and EKF algorithm,respectively. 展开更多
关键词 wireless sensor network(WSN)target tracking snake optimization algorithm extended Kalman filter maneuvering target
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Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs
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作者 Lei Yang Baixi Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2960-2981,共22页
In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hy... In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed. 展开更多
关键词 Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing extended finite element method(XFEM) Cohesive zone method(CZM)
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Extended Deep Learning Algorithm for Improved Brain Tumor Diagnosis System
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作者 M.Adimoolam K.Maithili +7 位作者 N.M.Balamurugan R.Rajkumar S.Leelavathy Raju Kannadasan Mohd Anul Haq Ilyas Khan ElSayed M.Tag El Din Arfat Ahmad Khan 《Intelligent Automation & Soft Computing》 2024年第1期33-55,共23页
At present,the prediction of brain tumors is performed using Machine Learning(ML)and Deep Learning(DL)algorithms.Although various ML and DL algorithms are adapted to predict brain tumors to some range,some concerns st... At present,the prediction of brain tumors is performed using Machine Learning(ML)and Deep Learning(DL)algorithms.Although various ML and DL algorithms are adapted to predict brain tumors to some range,some concerns still need enhancement,particularly accuracy,sensitivity,false positive and false negative,to improve the brain tumor prediction system symmetrically.Therefore,this work proposed an Extended Deep Learning Algorithm(EDLA)to measure performance parameters such as accuracy,sensitivity,and false positive and false negative rates.In addition,these iterated measures were analyzed by comparing the EDLA method with the Convolutional Neural Network(CNN)way further using the SPSS tool,and respective graphical illustrations were shown.The results were that the mean performance measures for the proposed EDLA algorithm were calculated,and those measured were accuracy(97.665%),sensitivity(97.939%),false positive(3.012%),and false negative(3.182%)for ten iterations.Whereas in the case of the CNN,the algorithm means accuracy gained was 94.287%,mean sensitivity 95.612%,mean false positive 5.328%,and mean false negative 4.756%.These results show that the proposed EDLA method has outperformed existing algorithms,including CNN,and ensures symmetrically improved parameters.Thus EDLA algorithm introduces novelty concerning its performance and particular activation function.This proposed method will be utilized effectively in brain tumor detection in a precise and accurate manner.This algorithm would apply to brain tumor diagnosis and be involved in various medical diagnoses aftermodification.If the quantity of dataset records is enormous,then themethod’s computation power has to be updated. 展开更多
关键词 Brain tumor extended deep learning algorithm convolution neural network tumor detection deep learning
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Design of Medical Rehabilitation Experience System Based on Extended Reality
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作者 Zhengjie Xu Qi Zhang +3 位作者 Kaidi Xue Hongjia Yang Luyao Wang Haolong Yang 《计算机科学与技术汇刊(中英文版)》 2024年第1期6-7,共2页
This project integrates Extended Reality technology with medical rehabilitation,integrating cloud rendering.interactive experience systems,adaptation platforms,and digital scene resources.It is a innovative applicatio... This project integrates Extended Reality technology with medical rehabilitation,integrating cloud rendering.interactive experience systems,adaptation platforms,and digital scene resources.It is a innovative application research in the era of metaverset medical rehabilitation.The project uses the Maya engine for the creation of digital assets,with Unity as the main functional development platform and PICO4 as the core device,to achieve interactive and fun experience effects for various rehabilitation training devices.It solves the problems of patients being dull,low participation,lack of confidence in traditional rehabilitation training.as well as the inability of medical staff to monitor patient progress in real time and adjust rehabilitation plans better. 展开更多
关键词 Relabilitation extended Reality INTERACTION UNITY
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Analysis of the Nursing Effect of Hierarchical Extended Nursing Based on The Guidance of Orem’s Theory in Patients with PICC Catheterization
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作者 Haixia Zhu Shuqiao Chen Hui Chi 《Journal of Clinical and Nursing Research》 2024年第3期215-219,共5页
Objective:To analyze the nursing effect of hierarchical extended nursing based on the guidance of Orem’s theory in patients with peripherally inserted central(PICC)catheterization.Methods:Ninety-one patients with PIC... Objective:To analyze the nursing effect of hierarchical extended nursing based on the guidance of Orem’s theory in patients with peripherally inserted central(PICC)catheterization.Methods:Ninety-one patients with PICC catheterization admitted to the hospital from May 2021 to May 2023 were selected and divided into a control group and an observation group,with 45 and 46 cases,respectively.The control group received routine nursing care,while the observation group received routine nursing care combined with hierarchical extended nursing based on the guidance of Orem’s theory for 3 months.Relevant indicators between the two groups were compared.Results:The improvement degree of various indicators in the observation group after nursing was better than that of the control group(P<0.05).Conclusion:Graded extended nursing based on the guidance of Orem’s theory improved the knowledge,belief,behavior,and self-efficacy of patients with PICC catheterization,and relieved their anxiety,depression,and other negative emotions.The nursing effect was deemed to be significant. 展开更多
关键词 Intravenous catheter Orem theory Graded extended care SELF-EFFICACY
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Effectiveness of Extended Care in Preventing Falls in Disabled Elderly and Its Impact on Quality of Life
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作者 Chun Tian Na Li Yan Yan 《Journal of Clinical and Nursing Research》 2024年第6期154-159,共6页
Objective:To analyze the value of extended care interventions for disabled elderly in preventing falls and optimizing quality of life.Methods:A sample of 60 cases of disabled elderly in a tertiary hospital from May 20... Objective:To analyze the value of extended care interventions for disabled elderly in preventing falls and optimizing quality of life.Methods:A sample of 60 cases of disabled elderly in a tertiary hospital from May 2022 to May 2023 was selected and grouped by the random number table method.The observation group received extended care,while the control group adopted routine care.The differences in complication rate,fall rate,36-Item Short Form Health Survey(SF-36)score,health knowledge awareness score,and nursing satisfaction were compared.Results:The complication rate and fall rate of the disabled elderly in the observation group were lower than those in the control group,P<0.05;the SF-36 score,health knowledge score,and nursing satisfaction of the observation group were higher than those of the control group,P<0.05.Conclusion:Extended care for the disabled elderly can reduce the risk of falls and complications related to disability,as well as optimize their cognition and improve their quality of life,which is efficient and feasible. 展开更多
关键词 Disabled elderly extended care FALLS Quality of life
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Analysis of the Effect of Integrated Extended Care Model in Improving the Quality of Life of Elderly Patients with Type 2 Diabetes Mellitus
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作者 Lili Liu 《Journal of Clinical and Nursing Research》 2024年第4期174-179,共6页
Objective: To analyze the impact of an integrated extended care model on improving the quality of life of elderly patients with Type 2 Diabetes Mellitus (T2DM). Methods: A total of 176 patients admitted to the hospita... Objective: To analyze the impact of an integrated extended care model on improving the quality of life of elderly patients with Type 2 Diabetes Mellitus (T2DM). Methods: A total of 176 patients admitted to the hospital from March 2015 to February 2018 were selected and randomly assigned to an observation group and a control group, with 88 patients each. The control group implemented conventional nursing interventions, and the observation group carried out an integrated extended-care model. The level of glycemic control, quality of life, and daily medication adherence between both groups were compared. Results: The observation group showed significant improvement in the level of glycemic control, and their fasting blood glucose, 2-hour postprandial blood glucose, and glycated hemoglobin levels were significantly lower as compared with those in the study group (P < 0.05). The quality of life of the patients in the observation group was higher than that of the control group (P < 0.05). The observation group had a higher compliance score (95.48 ± 7.45) than the control group (81.31 ± 8.72) (t = 8.909, P < 0.05). Conclusion: The integrated extended care model allows patients to receive comprehensive and individualized nursing services after discharge, which improves the effect of drug therapy and the quality of life of patients. 展开更多
关键词 Integrated extended care model Elderly type 2 diabetes mellitus Quality of life
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Analysis of the Effect of Extended Rehabilitation Care at Home on the Psychological Condition and Adherence to Medical Compliance Behavior of Patients with Coronary Heart Disease Combined with Heart Failure
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作者 Ailian Sun 《Journal of Clinical and Nursing Research》 2024年第2期98-103,共6页
Objective:To analyze the effects of providing extended rehabilitation nursing services at home to patients with coronary heart disease(CHD)combined with heart failure(CHF)on psychological improvement and adherence to ... Objective:To analyze the effects of providing extended rehabilitation nursing services at home to patients with coronary heart disease(CHD)combined with heart failure(CHF)on psychological improvement and adherence to medical compliance behavior.Methods:79 patients with CHD with CHF admitted to Sijia Town Central Health Hospital,Haimen District,Nantong City,Jiangsu Province,between June 2021 and June 2023 were selected and grouped according to the randomized numerical table method.The control group(39 cases)was provided with conventional nursing care and extended rehabilitation nursing care at home was provided to the observation group(40 cases).The psychological status,adherence to medical behaviors,cardiac function,and complications between both groups were compared.Results:The scores of anxieties and depression self-assessment scales(SAS,SDS)of patients in the observation group were lower than those of the control group(t=2.954,3.212;P<0.05);the compliance of patients in the observation group was higher than that of the control group(P<0.05).The levels of left ventricular ejection fraction,end-systolic and end-diastolic internal diameters(LVEF,LVESD,LVEDD)of patients in the observation group at 58.02±5.34%,44.49±5.16 mm,and 49.16±5.76 mm respectively were better than those of the control group after nursing care(t=3.205,3.288,2.633;P<0.05);the complication rate of the observation group was lower than that of the control group(P<0.05).Conclusion:Extended rehabilitation nursing at home exhibited a psychological regulation effect on CHD with CHF patients,improved their medical compliance,improved cardiac function,reduced the incidence of complications,and had significant application value. 展开更多
关键词 Home-based extended rehabilitation nursing Coronary heart disease Heart failure Psychological condition Compliance with medical behaviors
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eXtended Pom-Pom黏弹性流体的改进光滑粒子动力学模拟 被引量:1
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作者 许晓阳 周亚丽 余鹏 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第3期131-144,共14页
黏弹性流体广泛存在于自然界和工业生产中,对其复杂流变特性的研究具有重要的学术价值和应用意义.本文提出一种改进的光滑粒子动力学方法,对基于eXtended Pom-Pom模型的黏弹性流动进行了数值模拟.为了提高计算精度,采用一种不含核导数... 黏弹性流体广泛存在于自然界和工业生产中,对其复杂流变特性的研究具有重要的学术价值和应用意义.本文提出一种改进的光滑粒子动力学方法,对基于eXtended Pom-Pom模型的黏弹性流动进行了数值模拟.为了提高计算精度,采用一种不含核导数计算的核梯度修正离散格式.为了防止粒子穿透固壁,提出一种增强型的边界处理技术.为了消除张力不稳定性,将人工应力耦合到动量守恒方程中.运用改进光滑粒子动力学方法数值模拟了基于eXtended Pom-Pom模型的黏弹性Poiseuille流和黏弹性液滴撞击固壁问题,通过与解析解或有限差分方法解的比较以及对数值收敛性的评价,验证了改进光滑粒子动力学方法的有效性和优势,并在此基础上,深入分析了Reyonlds数、Weissenberg数、溶剂黏度比、各向异性参数、松弛时间比和分子链臂数等流变参数对流动过程的影响. 展开更多
关键词 光滑粒子动力学 extended Pom-Pom模型 POISEUILLE流 液滴
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Improved Adaptive Iterated Extended Kalman Filter for GNSS/INS/UWB-Integrated Fixed-Point Positioning 被引量:2
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作者 Qingdong Wu Chenxi Li +1 位作者 Tao Shen Yuan Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1761-1772,共12页
To provide stable and accurate position information of control points in a complex coastal environment,an adaptive iterated extended Kalman filter(AIEKF)for fixed-point positioning integrating global navigation satell... To provide stable and accurate position information of control points in a complex coastal environment,an adaptive iterated extended Kalman filter(AIEKF)for fixed-point positioning integrating global navigation satellite system,inertial navigation system,and ultra wide band(UWB)is proposed.In thismethod,the switched global navigation satellite system(GNSS)and UWB measurement are used as the measurement of the proposed filter.For the data fusion filter,the expectation-maximization(EM)based IEKF is used as the forward filter,then,the Rauch-Tung-Striebel smoother for IEKF filter’s result smoothing.Tests illustrate that the proposed AIEKF is able to provide an accurate estimation. 展开更多
关键词 Rauch-tung-striebel ultra wide band global navigation satellite system adaptive iterated extended kalman filter
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Application of extended criteria donor grafts in liver transplantation for acute-on-chronic liver failure:A retrospective cohort study 被引量:1
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作者 Jin-Long Gong Jia Yu +3 位作者 Tie-Long Wang Xiao-Shun He Yun-Hua Tang Xiao-Feng Zhu 《World Journal of Gastroenterology》 SCIE CAS 2023年第41期5630-5640,共11页
BACKGROUND There is no consensus on the usage of extended criteria donor(ECD)grafts in liver transplantation(LT)for acute-on-chronic liver failure(ACLF)patients.AIM To summarize the experience of using ECD livers in A... BACKGROUND There is no consensus on the usage of extended criteria donor(ECD)grafts in liver transplantation(LT)for acute-on-chronic liver failure(ACLF)patients.AIM To summarize the experience of using ECD livers in ACLF-LT.METHODS A retrospective cohort study was conducted,enrolling patients who underwent LT at the First Affiliated Hospital of Sun Yat-Sen University from January 2015 to November 2021.The patients were divided into ECD and non-ECD groups for analysis.RESULTS A total of 145 recipients were enrolled in this study,of which ECD and non-ECD recipients accounted for 53.8%and 46.2%,respectively.Donation after cardiac death(DCD)recipients accounted for the minority compared with donation after brain death(DBD)recipients(16.6%vs 83.4%).Neither overall survival nor graft survival significantly differed between ECD and non-ECD and DCD and DBD recipients.ECD grafts were associated with a significantly higher incidence of early allograft dysfunction(EAD)than non-ECD grafts(67.9%vs 41.8%,P=0.002).Postoperative outcomes between DCD and DBD recipients were comparable(P>0.05).ECD graft(P=0.009),anhepatic phase(P=0.034)and recipient gamma glutamyltransferase(P=0.016)were independent risk factors for EAD.Recipient preoperative number of extrahepatic organ failures>2(P=0.015)and intraoperative blood loss(P=0.000)were independent predictors of poor post-LT survival.CONCLUSION Although related to a higher risk of EAD,ECD grafts can be safely used in ACLF-LT.The main factors affecting post-LT survival in ACLF patients are their own severe preoperative disease and intraoperative blood loss. 展开更多
关键词 extended criteria donor Acute-on-chronic liver failure Liver transplantation
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Impact of extended nursing model after multi-disciplinary treatment on young patient with post-stroke 被引量:2
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作者 Xiao-Yan Xu Zhi-Juan Pang +4 位作者 Mei-Hui Li Kun Wang Jie Song Yue Cao Mao Fang 《World Journal of Clinical Cases》 SCIE 2023年第14期3148-3157,共10页
BACKGROUND Stroke has become one of the most serious life-threatening diseases due to its high morbidity,disability,recurrence and mortality rates.AIM To explore the intervention effect of multi-disciplinary treatment... BACKGROUND Stroke has become one of the most serious life-threatening diseases due to its high morbidity,disability,recurrence and mortality rates.AIM To explore the intervention effect of multi-disciplinary treatment(MDT)extended nursing model on negative emotions and quality of life of young patients with post-stroke.METHODS A total of 60 young stroke patients who were hospitalized in the neurology department of our hospital from January 2020 to December 2021 were selected and randomly divided into a control group and an experimental group,with 30 patients in each group.The control group used the conventional care model and the experimental group used the MDT extended nursing model.After the inhospital and 3-mo post-discharge interventions,the differences in negative emotions and quality of life scores between the two groups were evaluated and analyzed at the time of admission,at the time of discharge and after discharge,respectively.RESULTS There are no statistically significant differences in the negative emotions scores between the two groups at admission,while there are statistically significant differences in the negative emotions scores within each group at admission and discharge,at discharge and post-discharge,and at discharge and post-discharge.In addition,the negative emotions scores were all statistically significant at discharge and after discharge when compared between the two groups.There was no statistically significant difference in quality of life scores at the time of admission between the two groups,and the difference between quality of life scores at the time of admission and discharge,at the time of discharge and post-discharge,and at the time of admission and post-discharge for each group of patients was statistically significant.CONCLUSION The MDT extended nursing mode can improve the negative emotion of patients and improve their quality of life.Therefore,it can be applied in future clinical practice and is worthy of promotion. 展开更多
关键词 Multi-disciplinary treatment extended nursing model Young people with post-stroke Negative emotions Quality of life
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