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Intervention Effect of Lower Limb Rehabilitation Robot with Task-Oriented Training on Stroke Patients and Its Influence on KFAROM Score 被引量:1
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作者 Maiding He Li Huang +9 位作者 Dekun Tang Mei Qin Ping Zhan Xichan Wang Xia Gao Jianzhu Wang Na Yin hui xu Yonghua Yang Kaihua Tang 《Journal of Biosciences and Medicines》 2024年第9期62-72,共11页
Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to o... Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to our hospital from January 2023 to December 2023 were randomly divided into two groups, the control group (50 cases) was given task-oriented training assisted by nurses, and the observation group (50 cases) was given lower limb rehabilitation robot with task-oriented training. Lower limb balance, lower limb muscle strength, motor function, ankle function, knee flexion range of motion and walking ability were observed. Results: After treatment, the scores of BBS, quadriceps femoris and hamstrings in the observation group were significantly higher than those in the control group (P Conclusion: In the clinical treatment of stroke patients, the combination of task-oriented training and lower limb rehabilitation robot can effectively improve the lower limb muscle strength, facilitate the recovery of balance function, and have a significant effect on the recovery of motor function, which can improve the walking ability of stroke patients and the range of motion of knee flexion, and achieve more ideal therapeutic effectiveness. 展开更多
关键词 Lower Limb Rehabilitation Robot Task-Oriented Training STROKE KFAROM
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挖补修理复合材料层合板疲劳性能研究进展
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作者 邓金鑫 陈林 +2 位作者 徐辉 黄文俊 程小全 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期164-172,共9页
随着纤维增强复合材料结构的应用更加广泛,其结构修理问题日渐凸显。挖补修理在复合材料层合板修理中具有重要地位,而修理后结构的疲劳性能是评价结构修理质量的重要依据,因此对复合材料挖补修理层合板疲劳性能的研究意义重大。文中从... 随着纤维增强复合材料结构的应用更加广泛,其结构修理问题日渐凸显。挖补修理在复合材料层合板修理中具有重要地位,而修理后结构的疲劳性能是评价结构修理质量的重要依据,因此对复合材料挖补修理层合板疲劳性能的研究意义重大。文中从模型和试验两方面总结了挖补修理复合材料层合板疲劳性能研究现状,指出了当前挖补修理复合材料层合板疲劳性能研究存在的问题,可为复合材料结构挖补修理研究和工程应用提供参考。 展开更多
关键词 复合材料 层合板 挖补修理 疲劳性能
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Competitive oxidation behavior of Ni-based superalloy GH4738 at extreme temperature 被引量:3
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作者 hui xu Shufeng Yang +4 位作者 Enhui Wang Yunsong Liu Chunyu Guo Xinmei Hou Yanling Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期138-145,共8页
A high thrust-to-weight ratio poses challenges to the high-temperature performance of Ni-based superalloys. The oxidation behavior of GH4738 at extreme temperatures has been investigated by isothermal and non-isotherm... A high thrust-to-weight ratio poses challenges to the high-temperature performance of Ni-based superalloys. The oxidation behavior of GH4738 at extreme temperatures has been investigated by isothermal and non-isothermal experiments. As a result of the competitive diffusion of alloying elements, the oxide scale included an outermost porous oxide layer (OOL), an inner relatively dense oxide layer (IOL), and an internal oxide zone (IOZ), depending on the temperature and time. A high temperature led to the formation of large voids at the IOL/IOZ interface. At 1200℃, the continuity of the Cr-rich oxide layer in the IOL was destroyed, and thus, spallation occurred. Extension of oxidation time contributed to the size of Al-rich oxide particles with the increase in the IOZ. Based on this finding,the oxidation kinetics of GH4738 was discussed, and the corresponding oxidation behavior at 900-1100℃ was predicted. 展开更多
关键词 Ni-based superalloy GH4738 extreme temperature competitive oxidation oxidation mechanism oxidation kinetics
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Applying an Improved Dung Beetle Optimizer Algorithm to Network Traffic Identification 被引量:1
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作者 Qinyue Wu hui xu Mengran Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4091-4107,共17页
Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexi... Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexity,leading to practical problems in traffic identification data analytics.Since the original Dung Beetle Optimizer(DBO)algorithm,Grey Wolf Optimization(GWO)algorithm,Whale Optimization Algorithm(WOA),and Particle Swarm Optimization(PSO)algorithm have the shortcomings of slow convergence and easily fall into the local optimal solution,an Improved Dung Beetle Optimizer(IDBO)algorithm is proposed for network traffic identification.Firstly,the Sobol sequence is utilized to initialize the dung beetle population,laying the foundation for finding the global optimal solution.Next,an integration of levy flight and golden sine strategy is suggested to give dung beetles a greater probability of exploring unvisited areas,escaping from the local optimal solution,and converging more effectively towards a global optimal solution.Finally,an adaptive weight factor is utilized to enhance the search capabilities of the original DBO algorithm and accelerate convergence.With the improvements above,the proposed IDBO algorithm is then applied to traffic identification data analytics and feature selection,as so to find the optimal subset for K-Nearest Neighbor(KNN)classification.The simulation experiments use the CICIDS2017 dataset to verify the effectiveness of the proposed IDBO algorithm and compare it with the original DBO,GWO,WOA,and PSO algorithms.The experimental results show that,compared with other algorithms,the accuracy and recall are improved by 1.53%and 0.88%in binary classification,and the Distributed Denial of Service(DDoS)class identification is the most effective in multi-classification,with an improvement of 5.80%and 0.33%for accuracy and recall,respectively.Therefore,the proposed IDBO algorithm is effective in increasing the efficiency of traffic identification and solving the problem of the original DBO algorithm that converges slowly and falls into the local optimal solution when dealing with high-dimensional data analytics and feature selection for network traffic identification. 展开更多
关键词 Network security network traffic identification data analytics feature selection dung beetle optimizer
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双反射飞行时间质量分析器高分辨光电子成像谱仪研制
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作者 费泽杰 韩昌财 +7 位作者 王永天 徐辉 洪静 江一煌 周源 居鹤晨 董常武 刘洪涛 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期153-161,I0101,共10页
本文报道了一台结合电喷雾离子源和双反射飞行时间质谱的速度成像光电子能谱仪的研制过程,其可用于开展溶液中负离子的光电子能谱研究.在该装置中,电喷雾离子源产生的负离子由四极杆组成的离子引导系统传输至冷离子阱,并对负离子进行富... 本文报道了一台结合电喷雾离子源和双反射飞行时间质谱的速度成像光电子能谱仪的研制过程,其可用于开展溶液中负离子的光电子能谱研究.在该装置中,电喷雾离子源产生的负离子由四极杆组成的离子引导系统传输至冷离子阱,并对负离子进行富集和冷却,用于后端的质量选择和光电子能谱探测.该装置的关键技术之一是将双反射质量分析器与Wiley-McLaren离子加速聚焦设计进行了串联:这样可以有效地提高质谱分辨,从而准确地选择目标离子,其质量分辨率(M/△M)可达2000以上.该装置的高分辨光电子速度成像系统采用多极电子透镜设计,对于动能为0.59eV的光电子,其能谱峰的半高宽约为5.8meV,相对分辨率为~0.98%本文对该装置的工作原理,结构设计和性能测试情况进行了详细阐述。 展开更多
关键词 高分辨光电子成像 双反射飞行时间质谱 光电子能谱
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结构对SLS砂型次级烧结区的影响及其控制工艺研究
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作者 惠旭 李广宇 +2 位作者 刘文文 付宏源 姚山 《铸造》 CAS 2024年第7期915-922,共8页
设计了一种包含多种常见结构的精度测试件,用于探究结构对SLS打印的砂型成形精度的影响。通过打印和尺寸测量发现,纵向椭圆结构和圆孔的次级烧结相对其他结构更加严重,且存在方向性差异。采用低密度多道次的扫描方法,相较于常规扫描方法... 设计了一种包含多种常见结构的精度测试件,用于探究结构对SLS打印的砂型成形精度的影响。通过打印和尺寸测量发现,纵向椭圆结构和圆孔的次级烧结相对其他结构更加严重,且存在方向性差异。采用低密度多道次的扫描方法,相较于常规扫描方法,在0.1 J·mm·s^(-2)的总能量密度下可以将国标鼓形件的精度等级从无评级提高至5级,筋板的尺寸偏差降低到0.072 mm,显著改善了砂型的尺寸精度。 展开更多
关键词 激光3D打印 结构 成形精度 铸造砂型 次级烧结
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Effect of nursing intervention on rehabilitation of patients with chronic sinusitis and nasal polyps after nasal endoscopy 被引量:1
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作者 hui xu Miao Pan Lin Zhu 《World Journal of Clinical Cases》 SCIE 2024年第19期3785-3790,共6页
BACKGROUND Chronic sinusitis is a kind of chronic suppurative inflammation of the sinus mucosa.Nasal endoscopy is a good method to treat nasal polyps.However postoperative rehabilitation and care should not be neglect... BACKGROUND Chronic sinusitis is a kind of chronic suppurative inflammation of the sinus mucosa.Nasal endoscopy is a good method to treat nasal polyps.However postoperative rehabilitation and care should not be neglected.AIM To investigate the Effect of nursing intervention on the rehabilitation of patients with chronic sinusitis and nasal polyps(CSNPS)after nasal endoscopy.METHODS A total of 129 patients with CSNPS hospitalized from February 2017 to February 2019 were studied.Using the digital parity method,we investigated nursing cooperation strategies for endoscopic surgery.The comparison group(64 cases):Surgical nursing was carried out with traditional nursing measures;experimental group(65 cases):Surgical nursing was carried out by traditional nursing countermeasures+comprehensive nursing measures.We compared postoperative recovery rates,nursing satisfaction rates,and nasal cavity ratings between the two groups.RESULTS Experimental group patients with CSNPS had a significantly higher recovery rate(98.46%)compared to the control group(79.69%).This difference was statistically significant(χ2=11.748,P<0.05).Additionally,the satisfaction rate with treatment was also significantly higher in the experimental group(98.46%)compared to the control group(79.69%),with a statistically significant difference(χ2=11.748,P<0.05).Before nursing,there was no significant difference in sinus nasal cavity scores between the experimental group(20.29±7.25 points)and the control group(20.30±7.27 points)(t=0.008,P>0.05).However,after nursing,the sinus nasal cavity score in the experimental group(8.85±3.22 points)was significantly lower than that in the control group(14.99±5.02 points)(t=8.282,P<0.05).CONCLUSION Comprehensive nursing intervention in patients with CSNPS can significantly improve the total recovery rate after endoscopic surgery. 展开更多
关键词 Chronic sinusitis Nasal polyps Endoscopic surgery Comprehensive nursing Clinical effect
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Blastic plasmacytoid dendritic cell neoplasm:Two case reports 被引量:1
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作者 Yi-Qian Ma Zhan Sun +1 位作者 Yu-Mei Li hui xu 《World Journal of Clinical Oncology》 2024年第9期1207-1214,共8页
BACKGROUND Blastic plasmacytoid dendritic cell tumor(BPDCN)is a rare and highly invasive lymphohematopoietic tumor that originates from plasmacytoid dendritic cells.BPDCN has an extremely poor prognosis.Skin lesions a... BACKGROUND Blastic plasmacytoid dendritic cell tumor(BPDCN)is a rare and highly invasive lymphohematopoietic tumor that originates from plasmacytoid dendritic cells.BPDCN has an extremely poor prognosis.Skin lesions are usually the first manifestation of BPDCN,although the tumor may also invade the bone marrow,lymph nodes,peripheral blood,and other parts of the body,leading to several other manifestations,requiring further differentiation through skin biopsy and immunohistochemistry.CASE SUMMARY In the present paper,the cases of 2 patients diagnosed with BPDCN are discussed.The immunohistochemistry analysis of these 2 patients revealed positivity for CD4,CD56,and CD123.Currently,no standard chemotherapy regimen is available for BPDCN.Therefore,intensive therapy for acute lymphoblastic leukemia was applied as the treatment method for these 2 cases.CONCLUSION Although allogeneic bone marrow transplantation could be further effective in prolonging the median survival the ultimate prognosis was unfavorable.Future treatment modalities tailored for elderly patients will help prolong survival. 展开更多
关键词 Blastic plasmacytoid dendritic cell neoplasm SKIN CD4 CD56 CD123 Venetoclax Case report
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From 0D to 3D:Hierarchical structured high-performance free-standing silicon anodes based on binder-induced topological network architecture
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作者 Yihong Tong Ruicheng Cao +4 位作者 Guanghui xu Yifeng Xia Hongyuan xu Hong Jin hui xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期16-23,I0002,共9页
Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal ... Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is designed.Essentially,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking junctions.In which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of electrodes.Benefiting from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical prospect.Furthermore,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization process.Thus,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges. 展开更多
关键词 Topological network SELF-STABILIZATION FLEXIBILITY FREE-STANDING Silicon anode
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A simple route for preparation of TRIP-assisted Si-Mn steel with excellent performance using direct strip casting
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作者 hui xu Lejun Zhou +1 位作者 Wanlin Wang Yang Yi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2173-2181,共9页
The complex producing procedures and high energy-consuming limit the large-scale production and application of advanced high-strength steels(AHSSs).In this study,the direct strip casting(DSC)technology with unique sub... The complex producing procedures and high energy-consuming limit the large-scale production and application of advanced high-strength steels(AHSSs).In this study,the direct strip casting(DSC)technology with unique sub-rapid solidification characteristics and cost advantages was applied to the production of low-alloy Si-Mn steel with the help of quenching&partitioning(Q&P)concept to address these issues.Compared this method with the conventional compact strip production(CSP)process,the initial microstructure formed under different solidification conditions and the influence of heat treatment processes on the final mechanical properties were in-vestigated.The results show that the initial structure of the DSC sample is a dual-phase structure composed of fine lath martensite and bainite,while the initial structure of the CSP sample consists of pearlite and ferrite.The volume fraction and carbon content of retained austenite(RA)in DSC samples are usually higher than those in CSP samples after the same Q&P treatment.DSC samples typically demonstrate better comprehensive mechanical properties than the CSP sample.The DSC sample partitioned at 300℃ for 300 s(DSC-Pt300)achieves the best comprehensive mechanical properties,with yield strength(YS)of 1282 MPa,ultimate tensile strength(UTS)of 1501 MPa,total elongation(TE)of 21.5%,and product of strength and elongation(PSE)as high as 32.3 GPa·%.These results indicate that the excellent mechanical properties in low-alloy Si-Mn steel can be obtained through a simple process(DSC-Q&P),which also demonstrates the superiority of DSC technology in manufacturing AHSSs. 展开更多
关键词 direct strip casting sub-rapid solidification quenching and partitioning TRIP-assisted AHSSs microstructure
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Theoretical and numerical research on the dynamic launch response of carbon fiber composite cartridges
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作者 Ruijie Zhang hui xu +2 位作者 Chenlei Huang Kun Liu Zhilin Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期426-436,共11页
Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of ... Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of composite material cartridges is established based on the thick-walled cylinder theory and rate-dependent constitutive model of composite materials.The correctness of the theoretical model is validated through finite element simulations of cartridge deformation.The influence of chamber pressure and cartridge wall thickness on the cartridge's deformation process and stress distribution is analyzed.The results indicate that the primary deformation of composite material cartridges inside the chamber is elastic deformation.Compared to metal cartridges,composite material cartridges require higher pressure for touching-chamber and are more prone to developing gaps after unloading to ensure smooth extraction.During the deformation process,the touching-chamber behavior of the cartridge can improve the stress distribution.Under the same chamber pressure,the touching-chamber behavior can reduce the circumferential stress by approximately 30%.The inner wall surface of the cartridge is a critical area that requires attention.The touching-chamber behavior can be facilitated by appropriately reducing the cartridge wall thickness while ensuring overall strength.This study can provide guidance for the optimization design of composite material cartridges. 展开更多
关键词 Composite material cartridges Dynamic response Thick-walled cylinder theory Finite element simulation Toughing-chamber behavior
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Enhancing CO_(2) transport with plasma-functionalized ionic liquid membranes
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作者 舒茹晨 许卉 +5 位作者 裴晨霄 王楠 刘新刚 侯剑源 袁圆 张仁熙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期74-81,共8页
The ionic liquid(IL) 1-butyl-3-methylimidazolium tetrafluoroborate treated with radiofrequency plasma is proposed for functionalization and immobilization on polyethersulfone supports to form supported ionic liquid me... The ionic liquid(IL) 1-butyl-3-methylimidazolium tetrafluoroborate treated with radiofrequency plasma is proposed for functionalization and immobilization on polyethersulfone supports to form supported ionic liquid membranes for CO_(2) separation.The effects of treatment time and transmembrane pressure difference on CO_(2) permeance were evaluated.The best gas permeation performance was obtained with a treatment time of 10 min and the transmembrane pressure difference was 0.25 MPa.Characterization of the materials by Fourier transform infrared spectroscopy,x-ray photoelectron spectroscopy and nuclear magnetic resonance spectroscopy demonstrates that the IL is grafted with carboxyl groups and deprotonated through plasma treatment.A preliminary mechanism for the plasma treatment and facilitated transport of CO_(2)has been proposed on this basis. 展开更多
关键词 ionic liquids carbon dioxide supported ionic liquid membranes facilitated transport radiofrequency plasma
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Oxidative stress mediates glycidol-induced endothelial injury and its protection by 6-C-(E-2-fluorostyryl)naringenin
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作者 Yue Zhou hui xu +3 位作者 Ka-Wing Cheng Feng Chen Qian Zhou Mingfu Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2584-2594,共11页
Glycidol is a common lipid-derived foodborne toxicant mainly presents in refined oils and related foodstuffs.Vascular endothelial cells may be potential targets of the deleterious effects associated with glycidol expo... Glycidol is a common lipid-derived foodborne toxicant mainly presents in refined oils and related foodstuffs.Vascular endothelial cells may be potential targets of the deleterious effects associated with glycidol exposure.In human umbilical vein endothelial cells(HUVECs),we found that glycidol treatment promoted endothelialto-mesenchymal transition(EndMT)at a lower concentration(0.5 mmol/L),while induced apoptosis and inflammation at a higher concentration(1 mmol/L).These harmful effects were achieved by the activation of NF-κB/MAPK signaling pathway and were mediated by reactive oxygen species(ROS).In addition,the protective potential of 6-C-(E-2-fluorostyryl)naringenin(6-CEFN)against glycidol was evaluated and compared with naringenin.HUVECs pre-treated with 6-CEFN,but not naringenin,displayed resistance to endothelial dysfunction caused by glycidol. 展开更多
关键词 GLYCIDOL Endothelial cells 6-C-(E-2-fluorostyryl)naringenin Oxidative stress Endothelial-to-mesenchymal transition
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Effects of Different Concentrations of Sulfate Ions on Carbonate Crude Oil Desorption:Experimental Analysis and Molecular Simulation
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作者 Nannan Liu Hengchen Qi +1 位作者 hui xu Yanfeng He 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1731-1741,共11页
Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate ... Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate rock is still unknown.This study examines the variations in the wettability of the surface of carbonate rocks in solutions containing varying amounts of sodium sulfate and pure water.The problem is addressed in the framework of molecular dynamics simulation(Material Studio software)and experiments.The experiment’s findings demonstrate that sodium sulfate can increase the rate at which oil moisture is turned into water moisture.The final contact angle is smaller than that of pure water.The results of the simulations show that many water molecules travel down the water channel under the influence of several powerful forces,including the electrostatic force,the van der Waals force and hydrogen bond,crowding out the oil molecules on the calcite’s surface and causing the oil film to separate.The relative concentration curve of water and oil molecules indicates that the separation rate of the oil film on the surface of calcite increases with the number of sulfate ions. 展开更多
关键词 Carbonate rocks WETTABILITY sulfate ions CONCENTRATION molecular simulation DESORPTION
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Numerical Simulation of Droplet Generation in Coaxial Microchannels
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作者 Zongjun Yin Rong Su hui xu 《Fluid Dynamics & Materials Processing》 EI 2024年第3期487-504,共18页
In this study,numerical simulations of the pinching-off phenomena displayed by the dispersed phase in a continuous phase have been conducted using COMSOL Multiphysics(level-set method).Four flow patterns,namely“drop ... In this study,numerical simulations of the pinching-off phenomena displayed by the dispersed phase in a continuous phase have been conducted using COMSOL Multiphysics(level-set method).Four flow patterns,namely“drop flow”,“jet flow”,“squeeze flow”,and“co-flow”,have been obtained for different flow velocity ratios,channel diameter ratios,density ratios,viscosity ratios,and surface tension.The flow pattern map of two-phase flow in coaxial microchannels has been obtained accordingly,and the associated droplet generation process has been critically discussed considering the related frequency,diameter,and pinch-off length.In particular,it is shown that the larger the flow velocity ratio,the smaller the diameter of generated droplets and the shorter the pinch-off length.The pinch-off length of a droplet is influenced by the channel diameter ratio and density ratio.The changes in viscosity ratio have a negligible influence on the droplet generation pinching frequency.With an increase in surface tension,the frequency of generation and pinch-off length of droplets decrease,but for small surface tension the generation diameter of droplet increases. 展开更多
关键词 Droplet generation characteristics coaxial microchannels flow patterns pinch-off length
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Log interpretation of carbonate rocks based on petrophysical facies constraints
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作者 hui xu Hongwei Xiao +4 位作者 Guofeng Cheng Nannan Liu Jindong Cui Xing Shi Shangping Chen 《Energy Geoscience》 EI 2024年第3期39-51,共13页
The complex pore structure of carbonate reservoirs hinders the correlation between porosity and permeability.In view of the sedimentation,diagenesis,testing,and production characteristics of carbonate reservoirs in th... The complex pore structure of carbonate reservoirs hinders the correlation between porosity and permeability.In view of the sedimentation,diagenesis,testing,and production characteristics of carbonate reservoirs in the study area,combined with the current trends and advances in well log interpretation techniques for carbonate reservoirs,a log interpretation technology route of“geological information constraint+deep learning”was developed.The principal component analysis(PCA)was employed to establish lithology identification criteria with an accuracy of 91%.The Bayesian stepwise discriminant method was used to construct a sedimentary microfacies identification method with an accuracy of 90.5%.Based on production data,the main lithologies and sedimentary microfacies of effective reservoirs were determined,and 10 petrophysical facies with effective reservoir characteristics were identified.Constrained by petrophysical facies,the mean interpretation error of porosity compared to core analysis results is 2.7%,and the ratio of interpreted permeability to core analysis is within one order of magnitude,averaging 3.6.The research results demonstrate that deep learning algorithms can uncover the correlation in carbonate reservoir well logging data.Integrating geological and production data and selecting appropriate machine learning algorithms can significantly improve the accuracy of well log interpretation for carbonate reservoirs. 展开更多
关键词 Carbonate reservoir Principal component analysis(PCA) Bayesian stepwise discriminant analysis Petrophysical facies Well log interpretation
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Investigation on Temperature Field Calibration and Analysis of Wind Tunnel
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作者 Zhaokun Ren Zhanyuan Ma +3 位作者 Yue Zhang Hongda xu Yunxiang Wang hui xu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第3期63-79,共17页
For wind tunnels,it is essential to conduct temperature and flow field calibration on their test section,which is an important indicator for evaluating the quality of wind tunnel flow fields.In the paper,a truss compo... For wind tunnels,it is essential to conduct temperature and flow field calibration on their test section,which is an important indicator for evaluating the quality of wind tunnel flow fields.In the paper,a truss composed of temperature sensors was used to calibrate the temperature field of a completed wind tunnel section.By adjusting the distance between the temperature measurement truss and the nozzle,as well as the wind speed,the temperature field distribution data at different positions could be obtained.Analyze these data to identify important factors that affect the distribution of temperature field.Simultaneously,the temperature field of the wind tunnel was simulated accordingly.The purpose is to further analyze the fluid heat transfer between air and wind tunnel walls through numerical simulation.Through the above analysis methods,the quality of the temperature field in the wind tunnel has been further verified,providing reference for future wind tunnel tests of relevant models. 展开更多
关键词 wind tunnel temperature field numerical simulation fluid heat transfer
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基于主从博弈和贪心策略的含电动汽车主动配电网优化调度 被引量:31
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作者 张潇 栗然 +2 位作者 马涛 回旭 刘英培 《电力自动化设备》 EI CSCD 北大核心 2020年第4期103-110,共8页
随着入网的电动汽车规模增加,为了实现电网与车主的双赢不仅要考虑其无序充放电对电网负荷的影响,还要计及双方的成本。基于此,建立了主动配电网与电动汽车主从博弈模型。上层以配电网运行成本最低为目标,通过合理的电价及激励策略引导... 随着入网的电动汽车规模增加,为了实现电网与车主的双赢不仅要考虑其无序充放电对电网负荷的影响,还要计及双方的成本。基于此,建立了主动配电网与电动汽车主从博弈模型。上层以配电网运行成本最低为目标,通过合理的电价及激励策略引导电动汽车充放电,并协调优化分布式电源及储能;下层基于贪心策略进行两阶段优化,先以分时电价下充放电成本最低为目标优化充放电策略,在不减少收益的约束下,再最大化电网对减小负荷波动给予的激励调整策略。通过改进的IEEE 33节点系统算例分析表明,该模型在最大化双方利益的同时极大地缩小了负荷峰谷差,避免了大量电动汽车充电引起新的高峰。 展开更多
关键词 主动配电网 电动汽车 主从博弈 贪心策略 两阶段优化 峰谷差
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基于卷积长短期记忆神经网络的短期风功率预测 被引量:35
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作者 栗然 马涛 +3 位作者 张潇 回旭 刘英培 尹晓钢 《太阳能学报》 EI CAS CSCD 北大核心 2021年第6期304-311,共8页
提出一种基于卷积长短期记忆神经网络(CNN-LSTM)的短期风功率预测模型。该模型以风电场风功率历史数据以及风速风向等数值天气预报(NWP)数据为输入对风功率进行预测。首先,利用主成分分析法(PCA)对原始多维气象数据变量进行预处理,然后... 提出一种基于卷积长短期记忆神经网络(CNN-LSTM)的短期风功率预测模型。该模型以风电场风功率历史数据以及风速风向等数值天气预报(NWP)数据为输入对风功率进行预测。首先,利用主成分分析法(PCA)对原始多维气象数据变量进行预处理,然后将处理过的气象数据和历史风功率数据通过卷积网络实现对数据的特征提取和进一步的数据降维,再通过长短期记忆网络实现对数据的拟合,并在神经网络的训练过程中引入DropConnect技术减小模型中的过拟合现象,最终实现风功率的精确预测。以中国西北某风电场的实测数据进行验证,结果表明所提方法能有效对风功率进行预测,较BP神经网络和支持向量机(SVM)有更高的预测精度。 展开更多
关键词 风功率预测 主成分分析 长短期记忆 卷积神经网络 DropConnect技术
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肺癌患者围手术期预防性抗凝的临床价值分析 被引量:13
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作者 徐慧 廖虎 +3 位作者 车国卫 周坤 杨梅 刘伦旭 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第10期767-772,共6页
背景与目的肺癌患者围手术期肺栓塞(pulmonary embolism, PE)发生率有增高的趋势,预防肺栓塞是加速康复外科的重要组成部分,然而肺癌患者围术期预防性抗凝时机仍存在争议。本研究旨在探讨肺癌患者围手术期应用抗凝药物预防肺栓塞的安全... 背景与目的肺癌患者围手术期肺栓塞(pulmonary embolism, PE)发生率有增高的趋势,预防肺栓塞是加速康复外科的重要组成部分,然而肺癌患者围术期预防性抗凝时机仍存在争议。本研究旨在探讨肺癌患者围手术期应用抗凝药物预防肺栓塞的安全性和有效性。方法连续收集2016年6月-2016年12月,在四川大学华西医院胸外科行胸腔镜肺解剖性肺切除术的肺癌患者共562例,其中56例肺癌患术前12 h开始应用低分子肝素(low molecular weight heparin, LMWH)抗凝直到出院;506例患者术后24 h开始应用直到出院。分析围手术期胸腔引流量、术后出血和肺栓塞发生率、肺部相关并发症等。结果 (1)凝血酶原时间(prothrombin time, PT)、活化部分凝血活酶时间(activated partial thromboplastin time, APTT)和国际标准化比值(international normalized ratio, INR)在术前[(11.5±3.9) s,(27.8±3.5) s,(0.96±0.06) s]与术后抗凝组[(11.4±1.4) s,(28.3±4.0) s,(0.98±0.07) s]均无统计学差异(P=0.796,P=0.250, P=0.137);Caprini评分在术前(3.1±1.8)和术后(3.3±1.5)抗凝组也无统计学差异(P=0.104);(2)麻醉时间和术中出血量在术前抗凝组[(130.2±53.9) min,(76.8±49.3) mL]和术后抗凝组[(142.2±56.5) min,(73.7±41.6)mL]均无统计学差异(P=0.067, P=0.201)。(3)术后72 h总引流量在术前抗凝组[(728.1±505.7) mL]显著高于术后抗凝组[(596.4±373.5) mL](P=0.005),而两组患者术后总引流量[(1,066.8±1,314.6) mL,(907.8±999.8) mL]无差异(P=0.203);(4)肺栓塞和术后出血发生率在术前(1.785%, 1.785%)和术后(0.019%, 0.039%)抗凝组均无显著性差异(P=0.525, P=0.300);(5)皮下气肿和肺部感染发生率在术前(1.785%, 14.285%)和术后(1.581%, 6.324%)抗凝组均无显著性差异(P=0.989, P=0.085)。结论肺癌患者术前或术后预防性应用抗凝药物临床效果相当。 展开更多
关键词 肺肿瘤 围手术期预防性抗凝 肺栓塞
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