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COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE) 被引量:1
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作者 段晓曼 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期78-102,共25页
In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strateg... In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry. 展开更多
关键词 Kahler Metrics complete Riemannian metrics open complex manifolds holomorphic bisectional curvature C*bundle almost homogeneous manifolds
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专业Bundles策略护理在骨折合并脾脏损伤护理中的应用价值
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作者 毕兰枝 《中国伤残医学》 2024年第8期142-145,共4页
目的:探讨与分析专业Bundles策略护理在骨折合并脾脏损伤护理中的应用价值.方法:选择2021年2月—2023年2月我院收治的76例骨折合并脾脏损伤患者为研究对象,根据随机信封抽签1∶1原则将其分为Bundles组与对照组,各38例.对照组在围手术期... 目的:探讨与分析专业Bundles策略护理在骨折合并脾脏损伤护理中的应用价值.方法:选择2021年2月—2023年2月我院收治的76例骨折合并脾脏损伤患者为研究对象,根据随机信封抽签1∶1原则将其分为Bundles组与对照组,各38例.对照组在围手术期实施常规护理,Bundles组在对照组基础上给予围手术期专业Bundles策略护理,2组护理观察时间均为14 d.记录2组患者的预后恢复、心理变化、并发症与护理满意度情况.结果:Bundles组术中出血量少于对照组,手术时间、术后肛门排气时间、术后肛门排便时间、术后下床活动时间、术后住院时间均短于对照组,组间差异有统计学意义(P<0.05);护理14 d后,2组SDS、SAS评分均低于护理前,且Bundles组低于对照组,差异有统计学意义(P<0.05);Bundles组并发症发生率低于对照组,差异有统计学意义(P<0.05);Bundles组护理满意度高于对照组,差异有统计学意义(P<0.05).结论:专业Bundles策略护理在骨折合并脾脏损伤护理中的应用能促进患者康复,可减少创伤,缓解患者的焦虑与抑郁情绪,并且还能提高安全性,减少不良事件的发生,患者更加满意. 展开更多
关键词 专业bundles策略护理 骨折 脾脏损伤 抑郁情绪 并发症 护理满意度
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MAXWELL-EINSTEIN METRICS ON COMPLETIONS OF CERTAIN C* BUNDLES 被引量:2
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作者 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期363-372,共10页
In this paper,we prove that for some completions of certain fiber bundles there is a Maxwell-Einstein metric conformally related to any given Kahler class.
关键词 Hermitian metrics Maxwell-Einstein metrics complex manifolds scalar curvature fiber bundle almost homogeneous manifolds
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Bundles策略在预防全麻患者术中低体温中的应用 被引量:2
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作者 王海军 邢春凤 +1 位作者 陈笑珍 鲍雷洪 《齐鲁护理杂志》 2023年第4期94-97,共4页
目的:探讨Bundles策略在预防全麻患者术中低体温中的应用效果。方法:将2021年7月1日~10月31日拟行全麻腹部手术的300例成年患者随机分为G1常规保温组和G2 Bundles保温组各150例,G1常规保温组术中实施常规保温方式,G2 Bundles保温组实施... 目的:探讨Bundles策略在预防全麻患者术中低体温中的应用效果。方法:将2021年7月1日~10月31日拟行全麻腹部手术的300例成年患者随机分为G1常规保温组和G2 Bundles保温组各150例,G1常规保温组术中实施常规保温方式,G2 Bundles保温组实施基于循证干预措施和可能引发热量损失途径制订预防术中低温的Bundles干预策略。比较两组不同时间的体温、血氧饱和度(SpO_(2))、心率、血压、呼吸,统计两组寒战、低体温、躁动、术中出血、异常心律事件发生率,记录气管导管拔管时间、PACU停留时间。结果:G2 Bundles保温组术中及术后体温、SpO_(2)、心率、呼吸等均高于G1常规保温组,而同期血压低于G1常规保温组(P<0.05);G2 Bundles保温组寒战、低体温、躁动、术中出血事件、异常心律事件发生率均低于G1常规保温组(P<0.05);G2 Bundles保温组气管导管拔管时间、PACU停留时间均短于G1常规保温组(P<0.01)。结论:将Bundles策略应用于全麻患者术中,有助于预防低体温、调节患者心电指标,减少不良事件。 展开更多
关键词 全麻患者 术中 低体温 bundles策略 预防护理
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Left bundle branch pacing set to outshine biventricular pacing for cardiac resynchronization therapy? 被引量:2
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作者 Akash Batta Juniali Hatwal 《World Journal of Cardiology》 2024年第4期186-190,共5页
The deleterious effects of long-term right ventricular pacing necessitated the search for alternative pacing sites which could prevent or alleviate pacinginduced cardiomyopathy.Until recently,biventricular pacing(BiVP... The deleterious effects of long-term right ventricular pacing necessitated the search for alternative pacing sites which could prevent or alleviate pacinginduced cardiomyopathy.Until recently,biventricular pacing(BiVP)was the only modality which could mitigate or prevent pacing induced dysfunction.Further,BiVP could resynchronize the baseline electromechanical dssynchrony in heart failure and improve outcomes.However,the high non-response rate of around 20%-30%remains a major limitation.This non-response has been largely attributable to the direct non-physiological stimulation of the left ventricular myocardium bypassing the conduction system.To overcome this limitation,the concept of conduction system pacing(CSP)came up.Despite initial success of the first CSP via His bundle pacing(HBP),certain drawbacks including lead instability and dislodgements,steep learning curve and rapid battery depletion on many occasions prevented its widespread use for cardiac resynchronization therapy(CRT).Subsequently,CSP via left bundle branch-area pacing(LBBP)was developed in 2018,which over the last few years has shown efficacy comparable to BiVP-CRT in small observational studies.Further,its safety has also been well established and is largely free of the pitfalls of the HBP-CRT.In the recent metanalysis by Yasmin et al,comprising of 6 studies with 389 participants,LBBPCRT was superior to BiVP-CRT in terms of QRS duration,left ventricular ejection fraction,cardiac chamber dimensions,lead thresholds,and functional status amongst heart failure patients with left bundle branch block.However,there are important limitations of the study including the small overall numbers,inclusion of only a single small randomized controlled trial(RCT)and a small follow-up duration.Further,the entire study population analyzed was from China which makes generalizability a concern.Despite the concerns,the meta-analysis adds to the growing body of evidence demonstrating the efficacy of LBBP-CRT.At this stage,one must acknowledge that the fact that still our opinions on this technique are largely based on observational data and there is a dire need for larger RCTs to ascertain the position of LBBPCRT in management of heart failure patients with left bundle branch block. 展开更多
关键词 Biventricular pacing Cardiac resynchronization therapy Conduction system pacing Left bundle branch-area pacing Left bundle branch block Electromechanical dssynchrony
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Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis 被引量:3
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作者 Farah Yasmin Abdul Moeed +7 位作者 Rohan Kumar Ochani Hamna Raheel Malik Ali Ehtsham Awan Ayesha Liaquat Arisha Saleem Muhammad Aamir Nael Hawwa Salim Surani 《World Journal of Cardiology》 2024年第1期40-48,共9页
BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore... BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT. 展开更多
关键词 Left bundle branch pacing Biventricular pacing QRS duration Left ventricular ejection fraction Heart failure
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Selective his bundle pacing eliminates crochetage sign:A case report 被引量:1
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作者 Yan-Guang Mu Ke-Sen Liu 《World Journal of Clinical Cases》 SCIE 2024年第22期5276-5282,共7页
BACKGROUND Crochetage sign is a specific electrocardiographic manifestation of ostium secundum atrial septal defects(ASDs),which is associated with the severity of the left-to-right shunt.Herein,we reported a case of ... BACKGROUND Crochetage sign is a specific electrocardiographic manifestation of ostium secundum atrial septal defects(ASDs),which is associated with the severity of the left-to-right shunt.Herein,we reported a case of selective his bundle pacing(SHBP)that eliminated crochetage sign in a patient with ostium secundum ASD.CASE SUMMARY A 77-year-old man was admitted with a 2-year history of chest tightness and shortness of breath.Transthoracic echocardiography revealed an ostium secundum ASD.Twelve-lead electrocardiogram revealed atrial fibrillation with a prolonged relative risk interval,incomplete right bundle branch block,and crochetage sign.The patient was diagnosed with an ostium secundum ASD,atrial fibrillation with a second-degree atrioventricular block,and heart failure.The patient was treated with selective his bundle pacemaker implantation.After the procedure,crochetage sign disappeared during his bundle pacing on the electrocardiogram.CONCLUSION S-HBP eliminated crochetage sign on electrocardiogram.Crochetage sign may be a manifestation of a conduction system disorder. 展开更多
关键词 Crochetage sign Atrial septal defect PACEMAKER Selective his bundle pacing Case report
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Left bundle branch area pacing combined with implantable cardioverter-defibrillator treatment for heart failure after myocardial infarction
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作者 Bing-Chen GUO Jian XU +4 位作者 Yan-Zong LIU Guo-Qing DU Bo YU Shu-Feng LI Wen-Juan DU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第5期577-582,共6页
Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing mode.Previous studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)p... Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing mode.Previous studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)patients with left bundle branch block(LBBB)and a narrower QRS duration(QRSd)to have a higher percentage of super responders,and lower pacing thresholds than biventricular pacing(BiVP). 展开更多
关键词 PACING branch bundlE
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A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks
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作者 Wen-Quan Deng Tian-Bo Liang +3 位作者 Wen-Zhong Wang Hao Liu Jun-Lin Wu Fu-Jian Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1099-1112,共14页
Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettabi... Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water imbibition.When the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. Furthermore, this model provides an avenue to calculate the imbibition rate in pores of different sizes during wettability alteration and capture the non-Darcy effect in micro-and nano-scale pores. 展开更多
关键词 Imbibition Multiphase flow Tight rock Interacting capillary bundle model Wettability
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Fiber Bundle Topology Optimization for Surface Flows
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作者 Yongbo Deng Weihong Zhang +2 位作者 Jihong Zhu Yingjie Xu Jan G Korvink 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期236-264,共29页
This paper presents a topology optimization approach for the surface flows on variable design domains.Via this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern ... This paper presents a topology optimization approach for the surface flows on variable design domains.Via this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized,where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base manifold.The fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber bundle.The material distribution method is used to achieve the evolution of the pattern of the surface flow.The evolution of the implicit 2-manifold is realized via a homeomorphous map.The design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDE filters.The two surface-PDE filters are coupled,because they are defined on the implicit 2-manifold and base manifold,respectively.The surface Navier-Stokes equations,defined on the implicit 2-manifold,are used to describe the surface flow.The fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev space.Several numerical examples have been provided to demonstrate this approach,where the combination of the viscous dissipation and pressure drop is used as the design objective. 展开更多
关键词 Fiber bundle Topology optimization 2-MANIFOLD Surface flow Material distribution method Porous medium model
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Optimized CUDA Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs
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作者 Pranay R. Kommera Suresh S. Muknahallipatna John E. McInroy 《Journal of Software Engineering and Applications》 2024年第4期172-201,共30页
The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its p... The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUDA code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUDA kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the BA algorithm. Our optimized CUDA implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared to 654 seconds for the sequential implementation, resulting in a speedup of 30×. Our optimized CUDA implementation presented in this paper has achieved a 3× speedup for the largest dataset compared to the previous naïve CUDA implementation. 展开更多
关键词 Scene Reconstruction bundle Adjustment LEVENBERG-MARQUARDT Non-Linear Least Squares Memory Throughput Computational Throughput Contiguous Memory Access CUDA Optimization
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Left bundle branch area pacing:A new era of cardiac resynchronization therapy?
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作者 Carlo Alberto Caruzzo Elia Rigamonti Francesca Romana Scopigni 《World Journal of Cardiology》 2024年第9期542-545,共4页
The recent systematic review and meta-analysis provided a comprehensive focus on the current state of cardiac resynchronization therapy(CRT).The authors determined the feasibility of physiological left bundle branch a... The recent systematic review and meta-analysis provided a comprehensive focus on the current state of cardiac resynchronization therapy(CRT).The authors determined the feasibility of physiological left bundle branch area pacing(LBBAP)in patients indicated for CRT through a careful analysis of trials.They found that LBBAP was associated with significant reductions in QRS duration,New York Heart Association functional class,B-type natriuretic peptide levels,and pacing thresholds as well as improvements in echocardiographic parameters compared to biventricular pacing. 展开更多
关键词 Left bundle branch pacing Biventricular pacing QRS duration Left ventricular ejection fraction Heart failure
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Improving pressure ulcer care in intensive care units:Evaluating the impact of bundled care and silver nanoparticle dressings
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作者 Hong Yu 《World Journal of Clinical Cases》 SCIE 2024年第19期3873-3881,共9页
BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effective... BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effectiveness and impact on patient satisfaction remain insufficiently investigated.AIM To assess the impact of bundled care along with silver nanoparticle dressing on PUs management and family satisfaction in critically ill trauma patients.METHODS A total of 98 critically ill trauma patients with PUs in intensive care unit(ICU)were included in this study.Patients were randomly assigned to either the control group(conventional care with silver nanoparticle dressing,n=49)or the intervention group(bundled care with silver nanoparticle dressing,n=49).The PU Scale for Healing(PUSH)tool was used to monitor changes in status of pressure injuries over time.Assessments were conducted at various time points:Baseline(day 0)and subsequent assessments on day 3,day 6,day 9,and day 12.Family satisfaction was assessed using the Family Satisfaction ICU 24 ques-tionnaire.RESULTS No significant differences in baseline characteristics were observed between the two groups.In the intervention group,there were significant reductions in total PUSH scores over the assessment period.Specifically,surface area,exudate,and tissue type parameters all showed significant improvements compared to the control group.Family satisfaction with care and decision-making was notably higher in the intervention group.Overall family satisfaction was significantly better in the intervention group.CONCLUSION Bundled care in combination with silver nanoparticle dressings effectively alleviated PUs and enhances family satisfaction in critically ill trauma patients.This approach holds promise for improving PUs management in the ICU,benefiting both patients and their families. 展开更多
关键词 Pressure ulcers Silver nanoparticle dressings bundled care Pressure ulcer scale for healing tool Family satisfaction
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Analysis of The Effect of Bundled Nursing Intervention on Lung Cancer Patients with a High Risk of PICC-Related Thrombosis
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作者 Jia Meng Jianglin Zang +3 位作者 Tianyu Gao Boyang Wu Xiaoyang Guo Wei Liu 《Journal of Clinical and Nursing Research》 2024年第4期231-236,共6页
Objective: To explore the effect of bundled nursing intervention on lung cancer patients with a high risk of PICC-related thrombosis. Methods: Eighty-six PICC patients were selected and randomly divided into a control... Objective: To explore the effect of bundled nursing intervention on lung cancer patients with a high risk of PICC-related thrombosis. Methods: Eighty-six PICC patients were selected and randomly divided into a control group and an observation group of 43 patients each. The control group received general nursing care and the observation group received bundled nursing intervention based on the control group. The occurrence of venous thrombosis, quality of life score, Zung self-rating depression scale (SDS) score, self-rating anxiety (SAS) score, and nursing satisfaction after treatment were compared between the two groups. Results: The incidence rate of PICC-related venous thrombosis in the observation group (2/4.652%) was lower than that of the control group (13/30.231%) after nursing intervention (P < 0.05). After the intervention, the quality-of-life scores of the observation group were higher than those of the control group (P < 0.001). After the intervention, the SDS and SAS scores of the observation group were lower than those of the control group (P < 0.001). The nursing satisfaction rate of the observation group (41/ 4.652%) was higher than that of the control group (35/18.604%) (P < 0.05). The difference is statistically significant. Conclusion: In the care of lung cancer patients with a high risk of PICC-related thrombosis, bundled nursing care achieved better results. 展开更多
关键词 Care bundle Lung cancer PICC THROMBOSIS
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基于Douglas-Peucker和Quick Bundles算法的水上交通模式识别 被引量:4
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作者 陈信强 徐祥龙 +3 位作者 彭静 孙洋 王梓创 阎莹 《上海海事大学学报》 北大核心 2022年第3期1-6,共6页
针对船舶航迹数据量大、数据冗余、航迹特征不明显等问题,提出一种融合道格拉斯-普克(Douglas-Peucker,DP)压缩算法和基于距离的快速捆绑包(Quick Bundles,QB)聚类算法的水上交通模式识别方法。该方法根据航迹数据特征、压缩率和压缩误... 针对船舶航迹数据量大、数据冗余、航迹特征不明显等问题,提出一种融合道格拉斯-普克(Douglas-Peucker,DP)压缩算法和基于距离的快速捆绑包(Quick Bundles,QB)聚类算法的水上交通模式识别方法。该方法根据航迹数据特征、压缩率和压缩误差等指标选择合理的压缩阈值实现大规模船舶自动识别系统(automatic identification system,AIS)数据的压缩。在此基础上,提出一种基于最小直接翻转距离的聚类指标,利用QB算法实现船舶航迹的有效聚类。实验结果表明,提出的方法既可以简化航迹聚类过程,也可准确高效地实现航迹聚类,为水上交通精细化管理与决策提供数据支撑。 展开更多
关键词 船舶航迹聚类 船舶自动识别系统(AIS) DOUGLAS-PEUCKER算法 Quick bundles算法
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Formation of hierarchical Fe7Se8 nanorod bundles with enhanced sodium storage properties 被引量:3
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作者 Wenzhi Tian Wenzhe Ma +3 位作者 Zhenyu Feng Fang Tian Haibo Li Jing Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期97-105,共9页
Ordered hierarchical architectures are attractive candidates for electrochemical energy storage applications.Herein,a facile self-template strategy is applied to prepare Fe7Se8 architectures with a monolithic structur... Ordered hierarchical architectures are attractive candidates for electrochemical energy storage applications.Herein,a facile self-template strategy is applied to prepare Fe7Se8 architectures with a monolithic structure via a self-synthesized single precursor and subsequent calcination at high temperature.With the support of oleylamine,the precursor is structurally targeted to engineer the Fe7Se8 microstructure,featuring nanorod bundles arranged along the longitudinal direction.Because of their ordered hierarchical structure,the Fe7Se8 nanorod bundles deliver a high reversible capacity of 300 m Ah g^-1 at 0.5 A g^-1,along with exceptional rate capability up to 20 A g^-1 and long-term cycle life over 8000 cycles,which represents the highest stability of Fe7Se8 anodes for sodium-ion batteries reported to date.The feasibility of the present strategy to prepare metal selenide structures highlights its promising potential for the rational and effective engineering of electrode materials responsible for the electrochemical performance of energy storage systems. 展开更多
关键词 Fe7Se8 HIERARCHICAL structure Nanorod bundles Sodium-ion BATTERIES OLEYLAMINE
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Effect of Testing Conditions on Fibre-Bundle Tensile Properties Part Ⅰ: Sample Preparation, Bundle Mass and Fibre Alignment of Wool Bundles 被引量:3
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作者 于伟东 严灏景 +1 位作者 Ron Postle Yang Shouren 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期74-80,共7页
Due to the effects of samples and testing conditions on fibre-bundle tensile behaviour, it is necessary to investigate the relationships between experimental factors and tensile properties for the fibre-bundle tensile... Due to the effects of samples and testing conditions on fibre-bundle tensile behaviour, it is necessary to investigate the relationships between experimental factors and tensile properties for the fibre-bundle tensile tester (TENSOR). The effects of bundle sample preparation, fibre bundle mass and fibre alignment have been tested. The experimental results indicated that (1) the low damage in combing and no free-end fibres in the cut bundle are most important for the sample preparation; (2) the reasonable bundle mass is 400700 tex, but the tensile properties measured should be modified with the bundle mass because a small amount of bundle mass causes the scatter results, while the larger is the bundle mass, the more difficult to comb fibres parallel and to clamp fibre evenly; and (3) the fibre irregular arrangement forms a slack bundle resulting in interaction between fibres, which will affect the reproducibility and accuracy of the tensile testing. 展开更多
关键词 FIBRE bundle wool tensile property modulus TENSOR
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HORIZONTAL LAPLACE OPERATOR IN REAL FINSLER VECTOR BUNDLES 被引量:2
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作者 钟春平 钟同德 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期128-140,共13页
A vector bundle F over the tangent bundle TM of a manifold M is said to be a Finsler vector bundle if it is isomorphic to the pull-back π^*E of a vector bundle E over M([1]). In this article the authors study the ... A vector bundle F over the tangent bundle TM of a manifold M is said to be a Finsler vector bundle if it is isomorphic to the pull-back π^*E of a vector bundle E over M([1]). In this article the authors study the h-Laplace operator in Finsler vector bundles. An h-Laplace operator is defined, first for functions and then for horizontal Finsler forms on E. Using the h-Laplace operator, the authors define the h-harmonic function and ho harmonic horizontal Finsler vector fields, and furthermore prove some integral formulas for the h-Laplace operator, horizontal Finsler vector fields, and scalar fields on E. 展开更多
关键词 h-Laplace operator h-harmonic Finsler vector bundle
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High-precision regulation synthesis of Fe-doped Co_(2)P nanorod bundles as efficient electrocatalysts for hydrogen evolution in all-pH range and seawater 被引量:8
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作者 Yan Lin Kaian Sun +4 位作者 Xiaomeng Chen Chen Chen Yuan Pan Xiyou Li Jun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期92-101,共10页
The hydrogen evolution reaction(HER)via water electrolysis has gained immense research attention.Seawater electrolysis provides great opportunities for sustainable energy production,but is extremely challenging.Transi... The hydrogen evolution reaction(HER)via water electrolysis has gained immense research attention.Seawater electrolysis provides great opportunities for sustainable energy production,but is extremely challenging.Transition metal phosphides are promising candidate electrocatalysts.Herein,we prepared a novel Fe-Co_(2)P bundle of nanorods(BNRs)for catalyzing the HER in seawater electrolysis and over the entire p H range.Cobalt phosphides with different crystal phases and morphologies were obtained by varying the Fe doping amount.The Co:Fe molar ratio of 1:0.5 was found to be optimum.The Fe doping improved the HER performance of Co_(2)P over the entire p H range by providing favorable electronic properties and morphology,lattice distortion,and special coordination environment.The Fe-Co_(2)P BNRs showed higher catalytic activity than 20%Pt/C in seawater at high potentials.The density functional theory calculations revealed that the Fe doping reduced the hydrogen binding strength of Co_(2)P to efficiently accelerate the HER kinetics and produce a favorable charge density.This study provides valuable insights into the design and development of high-efficiency HER catalysts for large-scale seawater electrolysis. 展开更多
关键词 Nanocrystal synthesis Transition metal phosphides Nanorod bundles Hydrogen evolution reaction Seawater electrolysis
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Single-phase Computational Fluid Dynamics Applicability for the Study of Three-dimensional Flow in 5×5 Rod Bundles with Spacer Grids 被引量:1
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作者 TIAN Ruifeng MAO Xiaohui +1 位作者 GAO Puzhen HUANG Yanping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期738-744,共7页
Spacer grids play an important role in pressurized water reactor(PWR) fuel assembly in that they have significant influence on the thermal-hydraulic characteristics of the reactor core.But so far,the numerical studi... Spacer grids play an important role in pressurized water reactor(PWR) fuel assembly in that they have significant influence on the thermal-hydraulic characteristics of the reactor core.But so far,the numerical studies are performed without regarding dimple and spring of spacer grids,just considering mixing vane.Moreover,these studies use k-ε turbulence model without considering the suitability of the other turbulence models upon the different spacer grids flow.A study is carried out to understand the 3-D single-phase flow in AFA-2G 5×5 rod bundles with spacer grids based on numerical method.In order to investigate the suitability of different turbulence models,k-ε model and k-ω model,the influence of different parts of spacer grid on the fluid flow is also predicted.By using second-order upwind scheme,hybrid grids technique,and improved SIMPLEC algorithm,the Reynolds averaged mass conservation and momentum conservation equations are solved,and the pressure and velocity field of flow are obtained.The numerical simulation results are compared with experiment results and the agreement is satisfactory.The simulation results show the influences of the spring,dimple and mixing vane,and the different characteristics of the k-ε model and k-ω model.Comparing with the experiment results,the simulation results suggest that the k-ω model is suitable for the simulation of the rod bundle flow with spacer grids;the spring and dimple are the main causes of the pressure loss in the spacer grid channel.The friction coefficient of the channel with spring and dimple is 1.5 times the coefficient of the channel with the vane.These results are beneficial to enhance the simulation ability of spacer grids flow and optimization design ability of spaces grid. 展开更多
关键词 rod bundles spacer grids turbulence model SIMPLEC algorithm
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