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Sudden Death as the Outcome of Cardiac Arrest,in a Portuguese Region:Where Do Resuscitation Manoeuvres Stand?
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作者 Rosa Henriques de Gouveia Adriana Martins Duarte Nuno Vieira 《World Journal of Cardiovascular Diseases》 2015年第8期227-232,共6页
Cardiac Arrest (CA) is a major health problem, due to short and long-term sequel? and to associated mortality. Despite the improvement of out-of-hospital and in-hospital resuscitation manoeuvres, unexpected sudden fat... Cardiac Arrest (CA) is a major health problem, due to short and long-term sequel? and to associated mortality. Despite the improvement of out-of-hospital and in-hospital resuscitation manoeuvres, unexpected sudden fatal events occur. The authors reported the features of a series of sudden death (SD) cases where cardiopulmonary resuscitation (CPR) was performed. Files of 1053 medico-legal autopsies, from victims aged ≥18 years-old, were reviewed. Cardiac Arrest leading to Sudden Death were found in 477 cases (45.3%), but only 199 (42%) of these had been submitted to resuscitation manoeuvres. There was an elderly male predominance. Both non-cardiac and cardiac CA/SD causes were present, despite the higher coronary artery disease incidence. Both out-of-hospital and in-hospital events took place. Age, severity of the disease, comorbidities and predominance of out-of-hospital CA were obstacles to successful CPR, leading to SD. Knowing the population characteristics may help to improve Emergency Assistance. 展开更多
关键词 Cardiac Arrest Resuscitation manoeuvres Sudden Death PORTUGAL
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Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?
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作者 Bin-bin LIU Bo-wen ZHAO +3 位作者 Fei-peng WU Tian HU Yin ZHAO Hong ZHANG 《Current Medical Science》 SCIE CAS 2023年第2期376-383,共8页
Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the V... Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal subjects.Methods Forty POAG and forty control subjects were subjected to the VM.Systemic and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,respectively.Heart rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,respectively.Results POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than controls.During VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all P<0.05).However,when we compared the changes above,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all P<0.05),while the changes in amplitudes of SCAR were smaller in POAG(P<0.05).Furthermore,from VM2 to VM4,the choroid thickness(ChT)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and ChT during the VM than controls.These reactions could be associated with autonomic dysfunction in POAG. 展开更多
关键词 primary open-angle glaucoma Valsalva manoeuvre autonomic dysfunction intraocular pressure Schlemm’s canal
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System Identification Modeling of Ship Manoeuvring Motion in 4 Degrees of Freedom Based on Support Vector Machines 被引量:6
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作者 王雪刚 邹早建 +1 位作者 余龙 蔡韡 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期519-534,共16页
Based on support vector machines, three modeling methods, i.e., white-box modeling, grey-box modeling and black-box modeling of ship manoeuvring motion in 4 degrees of freedom are investigated. With the whole-ship mat... Based on support vector machines, three modeling methods, i.e., white-box modeling, grey-box modeling and black-box modeling of ship manoeuvring motion in 4 degrees of freedom are investigated. With the whole-ship mathematical model for ship manoeuvring motion, in which the hydrodynamic coefficients are obtained from roll planar motion mechanism test, some zigzag tests and turning circle manoeuvres are simulated. In the white-box modeling and grey-box modeling, the training data taken every 5 s from the simulated 20°/20° zigzag test are used, while in the black-box modeling, the training data taken every 5 s from the simulated 15°/15°, 20°/20° zigzag tests and 15°, 25° turning manoeuvres are used; and the trained support vector machines are used to predict the whole 20°/20° zigzag test. Comparisons between the simulated and predicted 20°/20° zigzag tests show good predictive ability of the proposed methods. Besides, all mathematical models obtained by the proposed modeling methods are used to predict the 10°/10° zigzag test and 35° turning circle manoeuvre, and the predicted results are compared with those of simulation tests to demonstrate the good generalization performance of the mathematical models. Finally, the proposed modeling methods are analyzed and compared with each other in aspects of application conditions, prediction accuracy and computation speed. The appropriate modeling method can be chosen according to the intended use of the mathematical models and the available data needed for system identification. 展开更多
关键词 ship manoeuvring 4 degrees of freedom system identification support vector machines
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Parity recognition of blade number and manoeuvre intention classification algorithm of rotor target based on micro-Doppler features using CNN 被引量:4
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作者 WANG Wantian TANG Ziyue +1 位作者 CHEN Yichang SUN Yongjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期884-889,共6页
This paper proposes a parity recognition of blade number and manoeuvre intention classification algorithm of rotor target based on the convolutional neural network(CNN) using micro Doppler features. Firstly, the time-... This paper proposes a parity recognition of blade number and manoeuvre intention classification algorithm of rotor target based on the convolutional neural network(CNN) using micro Doppler features. Firstly, the time-frequency spectrograms are acquired from the radar echo by the short-time Fourier transform.Secondly, based on the obtained spectrograms, a seven-layer CNN architecture is built to recognize the blade-number parity and classify the manoeuvre intention of the rotor target. The constructed architecture contains a leaky rectified linear unit and a dropout layer to accelerate the convergence of the architecture and avoid over-fitting. Finally, the spectrograms of the datasets are divided into three different ratios, i.e., 20%, 33% and 50%,and the cross validation is used to verify the effectiveness of the constructed CNN architecture. Simulation results show that, on the one hand, as the ratio of training data increases, the recognition accuracy of parity and manoeuvre intention is improved at the same signal-to-noise ratio(SNR);on the other hand, the proposed algorithm also has a strong robustness: the accuracy can still reach 90.72% with an SNR of – 6 dB. 展开更多
关键词 micro-Doppler convolutional neural network(CNN) parity recognition of blade number manoeuvre intention classification
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BGK-EQUATION SIMULATION OF THE EXHAUST PLUME FORMED BY A MANOEUVRE THRUSTER IN OUTER SPACE 被引量:2
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作者 章光华 符松 赵建兵 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2001年第3期225-236,共12页
The general principle of utilizing the BGK equation to simulate a macroscopic gas flow is illustrated. Two typical examples, i.e., a low-speed axisymmetric submerged jet and the Prandtl-Meyer expansion to a vacuum, ar... The general principle of utilizing the BGK equation to simulate a macroscopic gas flow is illustrated. Two typical examples, i.e., a low-speed axisymmetric submerged jet and the Prandtl-Meyer expansion to a vacuum, are presented for validating the feasibility and accuracy of the BGK-equation simulation in continuum and non-continuum flow regimes. This approach is then used to simulate the exhaust plume formed by a small manoeuvre thruster of an artificial satellite in the outer space. The plume impingement on a flat surface perpendicular to the nozzle axis is also simulated by the same method. In the latter case the impingement force acting on the flat surface is calculated. When the flow reaches to the steady state the calculated impingement force is reasonably compared with the theoretical value of the nozzle thrust. 展开更多
关键词 BGK equation numerical simulation exhaust plume in outer space manoeuvre thruster of satellite
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Hepatic stress gene expression and ultrastructural features under intermittent Pringle manoeuvre 被引量:1
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作者 KwanMan IreneOi-LinNg Sheung-TatFan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第2期249-257,共9页
Background: Intermittent Pringle manoeuvre resul- ted in less blood loss and better preservation of liver function when it was applied for fewer than 120 mi- nutes. The mechanism of better preservation of liver functi... Background: Intermittent Pringle manoeuvre resul- ted in less blood loss and better preservation of liver function when it was applied for fewer than 120 mi- nutes. The mechanism of better preservation of liver function under intermittent Pringle manoeuvre at molecular level remains unclear. Furthermore, the ultrastructural features in the liver with chronic di- seases under intermittent Pringle manoeuvre have not been studied. The aim of the study is to investigate the expression of stress genes and ultrastructural change of the liver under intermittent Pringle ma- noeuvre. Methods: From July 1995 to February 1998, 131 pa- tients underwent hepatectomy for liver tumours (61 patients without Pringle manoeuvre and 70 patients with intermittent Pringle manoeuvre). Twenty-five patients (15 with Pringle manoeuvre and 10 without Pringle manoeuvre) were included in the study of he- patic stress gene expression during hepatectomy. Twenty-two patients (18 patients with intermittent Pringle manoeuvre and four patients without Pringle manoeuvre) were randomly assigned for electron mi- croscopic examination. Results: For the expression of stress genes, both the heat shock genes (HSP 70A and HSC 70) and acute phase genes (TNF-α and interleukin-6) were detec- ted simultaneously in the patients with or without in- termittent Pringle manoeuvre. The patients under in- termittent Pringle manoeuvre had relatively higher mRNA levels of heat shock gene 70 family, which is related to intracellular repair and protection. Induc- tion of TNF-α and interleukin-6 genes, which con- tributed to ischaemia-reperfusion injury and posto- perative complication, was not found in the patients under intermittent Pringle manoeuvre. Under the e- lectron microscopy, the hepatic ultrastructure was well maintained under intermittent Pringle manoeu- vre whatever the liver status, even when the accumu- lated ischaemic duration was extended to 120 min. Conclusion: Intermittent Pringle manoeuvre induced relatively higher expression of heat shock genes, which are related to intracellular homeostasis, and is consistent with the well maintenance of liver ultra- structure. 展开更多
关键词 Pringle manoeuvre ULTRASTRUCTURE gene expression STRESS
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Research on Master-slave Telerobot Force Telepresence Technology
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作者 蔡鹤皋 陈卫东 +1 位作者 贾国武 赵杰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第4期69-72,共4页
ResearchonMaster-slaveTelerobotForceTelepresenceTechnologyCAIHegaoCHENWeidongJIAGuowuZHAOJie(蔡鹤皋)(陈卫东)(贾国武)(... ResearchonMaster-slaveTelerobotForceTelepresenceTechnologyCAIHegaoCHENWeidongJIAGuowuZHAOJie(蔡鹤皋)(陈卫东)(贾国武)(赵杰)(RobotResearch... 展开更多
关键词 MASTER-SLAVE TELEROBOT FORCE TELEPRESENCE BILATERAL FORCE response control MANOEUVRABILITY
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Accordion Manoeuvre with Ilizarov Frame over Nail <i>in Situ</i>in a Case of Infected Non-Union of Femur: Discussion on Strategies: A Case Report
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作者 Ranjit Kr. Baruah 《Open Journal of Orthopedics》 2014年第7期183-188,共6页
Quiescent Type of H. Rosen & Stage 2 of C.L. Romano et al. for Infected Non Union of Femur after K-nailing (Küntscher nailing) require no debridement & removal of nail and therefore can be treated by a si... Quiescent Type of H. Rosen & Stage 2 of C.L. Romano et al. for Infected Non Union of Femur after K-nailing (Küntscher nailing) require no debridement & removal of nail and therefore can be treated by a single stage procedure. There are a few reports of treating aseptic non-union of femur by compression alone or compression distraction over nail by Ilizarov Technique. However, no case of Infected Non-Union femur being treated by Accordion Manoeuvre with Ilizarov over nail in situ (i.e. without exchange nailing) has been reported so far. Here, we are reporting a case of Infected Non-Union following K-nailing for a fracture shaft of femur in a 15-year-old female, who was treated by this technique as a single stage procedure. An Ilizarov frame was mounted on the femur with nail in situ followed by Accordion Manoeuvre. The fracture was healed in 5.6 months with two cycles of Accordion Manoeuvre followed by rhythmic compression. There was no recurrence of infection. 展开更多
关键词 INFECTED NON-UNION FEMUR ACCORDION Manoeuvre by ILIZAROV over NAIL in Situ
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Pitfalls in spirometry: Clinical relevance
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作者 Andrea Antonelli Giulia Michela Pellegrino +1 位作者 Giuseppe Francesco Sferrazza Papa Riccardo Pellegrino 《World Journal of Respirology》 2014年第3期19-25,共7页
Spirometry is one of the functional tests most used in respiratory medicine to assess lung function in health and disease conditions.Its success is grounded on solid principles of lung mechanics that state that maxima... Spirometry is one of the functional tests most used in respiratory medicine to assess lung function in health and disease conditions.Its success is grounded on solid principles of lung mechanics that state that maximal flow on expiration is limited by the physical properties of airways and lung parenchyma.In contrast,on inspiration,flow depends on the force generated by the inspiratory muscles.Reduced expiratory forced flow and volumes usually reflect a deviation from health conditions.Yet due to a complex interplay of different obstructive and restrictive lung diseases within the multiple structural dimensions of the respiratory system,flows and volumes do not always perfectly reflect the impact of the disease on lung function.The present review is intended to shed light on a series of artefacts and biological phenomena that may confound the clinical interpretation of the main spirometric measurements.Among them is thoracic gas compression volume,the volume and time history of the inspiratory manoeuvre that precedes the forced expiration,the effects of heterogeneous distribution of the disease across the respiratory system,and the changes in lung elastic recoil. 展开更多
关键词 SPIROMETRY Thoracic gas compression VOLUME VOLUME HISTORY EFFECTS of the deep breath Time HISTORY EFFECTS of the preceding inspiratory manoeuvre Ventilation HETEROGENEITIES Lung elastic RECOIL Clinical interpretation
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Application Of Fuzzy-Logic In Ship Manoeuvring In Confined Waters
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作者 S.Surendran S.K Lee 《Sustainable Marine Structures》 2019年第1期11-20,共10页
A ship manoeuvring problem is solved using an algorithm built on fuzzy logic.The manoeuvring model for a design ship is coded in C++and the results are presented here.A bulk carrier is assumed as design ship for a new... A ship manoeuvring problem is solved using an algorithm built on fuzzy logic.The manoeuvring model for a design ship is coded in C++and the results are presented here.A bulk carrier is assumed as design ship for a newly setting up harbor along the east coast of India.The harbor mouth is 25 km away from the deep water zone.The approach channel is straight along the 22 km length.Laterally restricted and shallow waters are considered and their influences on hydrodynamic derivatives are discussed.Some sample problems are solved.Trajectories,ship heading,rudder angle,velocities and accelerations,of the moving vessel,are calculated and presented for clarity.The developed code is robust in the sense that any designer or user can easily interact with various input parameters to verify the outputs and their suitability for the design ship meant for a particular water front location.The results are validated using another algorithm built on PID which is discussed in brief. 展开更多
关键词 MANOEUVRABILITY RUDDER HARBOUR CONTROL
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Lane-changing decision rule with the difference of traffic flow's variation in multi-lane highway for connected and autonomous vehicles
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作者 Chuanyao Li Dexin Huang +1 位作者 Tao Wang Jin Qin 《Transportation Safety and Environment》 EI 2023年第3期112-121,共10页
Drivers are not far-sighted when they execute lane-changing manipulation.To address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicl... Drivers are not far-sighted when they execute lane-changing manipulation.To address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicles(e.g.time headway)-More specifically,connected and autonomous vehicles(CAVs)change lanes in advance if they find severer flow reducing in the lanes,while CAVs should maintain the car-following state if the variations of traffc flow in all lanes have a similar trend.To ilustrate the idea,this study frst calibrates two classic car-following models and a lane-changing model,and then conducts numerical simulations to illustrate the short-sighted decision of drivers.The study incorporates the idea into a lane-changing decision rule by changing the lane-changing model's pa-rameter,and conducts numerical tests to evaluate the effectiveness of the lane-changing decision rule in a multi-lane highway with a bottleneck.The results of this study indicate that the new lane-changing decision rule can substantially improve the throughput of the traffic flow,especially when the inflow exceeds the remaining capacity of the road.The lane-changing rule and results can bring insights into the control of CAVs,as well as the driver assistance system in connected vehicles. 展开更多
关键词 lane-changing manoeuvre decision rule connected and autonomous vehicle(CAV)
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IDENTIFICATION OF ABKOWITZ MODEL FOR SHIP MANOEUVRING MOTION USING ε-SUPPORT VECTOR REGRESSION 被引量:13
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作者 ZHANG Xin-guang ZOU Zao-jian 《Journal of Hydrodynamics》 SCIE EI CSCD 2011年第3期353-360,共8页
By analyzing the data of longitudinal speed, transverse speed and rudder angle etc. in the simulated 10°/10°zigzag test, the hydrodynamic derivatives in the Abkowitz model for ship manoeuvring motion are ide... By analyzing the data of longitudinal speed, transverse speed and rudder angle etc. in the simulated 10°/10°zigzag test, the hydrodynamic derivatives in the Abkowitz model for ship manoeuvring motion are identified by using e-Support Vector Regression (ε -SVR). To damp the extent of parameter drift, a series of random numbers are added into the training samples to reconstruct the training samples. The identification results of the hydrodynamic derivatives are compared with the Planar Motion Mechanism (PMM) test results to verify the identification method. By using the identified Abkowitz model, 20°/20° zigzag test is numerically simulated. The simulated results are compared with those obtained by using the Abkowitz model where the hydrodynamic derivatives are obtained from PMM tests. The agreement is satisfactory, which shows that the regressive Abkowitz model has a good generalization performance. 展开更多
关键词 ship manoeuvring Abkowitz model parameter identification e -Support Vector Regression ~ -SVR)
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System identification modelling of ship manoeuvring motion based on ?- support vector regression 被引量:9
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作者 王雪刚 邹早建 +1 位作者 侯先瑞 徐锋 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第4期502-512,共11页
Based on the ε - support vector regression, three modelling methods for the ship manoeuvring motion, i.e., the white-box modelling, the grey-box modelling and the black-box modelling, are investigated. The 10°/1... Based on the ε - support vector regression, three modelling methods for the ship manoeuvring motion, i.e., the white-box modelling, the grey-box modelling and the black-box modelling, are investigated. The 10°/10°, 20°/20° zigzag tests and the 35° turning circle manoeuvre are simulated. Part of the simulation data for the 20°/20° zigzag test are used to train the support vectors, and the trained support vector machine is used to predict the whole 20° / 20° zigzag test. Comparison between the simula- ted and predicted 20° / 20° zigzag test shows a good predictive ability of the three modelling methods. Then all mathematical models obtained by the modelling methods are used to predict the 10°/10° zigzag test and 35° turning circle manoeuvre, and the predicted results are compared with those of simulation tests to demonstrate the good generalization performance of the mathematical models. Finally, the modelling methods are analyzed and compared with each other in terms of the application conditions, the prediction accuracy and the computation speed. An appropriate modelling method can be chosen according to the intended use of the mathematical models and the available data for the system identification. 展开更多
关键词 ship manoeuvring hydrodynamic coefficients mathematical model system identification ε - support vector regression
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Combined incisional ropivacaine infiltration and pulmonary recruitment manoeuvre for postoperative pain relief after diagnostic hysteroscopy and laparoscopy 被引量:3
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作者 Liu Huili Ma Caihong Zhang Xiaoqing Yu Chen Yang Yan Song Xueling Tang Yi Guo Xiangyang 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第5期825-829,共5页
Background Preoperative incisional local anaesthesia with ropivacaine is a common method of providing postlaparoscopy pain relief.The pulmonary recruitment manoeuvre also provides pain relief,but the combined effect o... Background Preoperative incisional local anaesthesia with ropivacaine is a common method of providing postlaparoscopy pain relief.The pulmonary recruitment manoeuvre also provides pain relief,but the combined effect of these two methods on pain following laparoscopic procedures has not been reported.We investigated the efficacy of combining local anaesthetic infiltration of ropivacaine with pulmonary recruitment manoeuvre on postoperative pain following diagnostic hysteroscopy and laparoscopy.Methods This prospective,randomized,controlled study involved 60 patients divided into two groups (n=30,each).Group 1 received 20 ml of 0.5% ropivacaine injected peri-incisionally preoperatively,with intra-abdominal carbon dioxide removed by passive deflation.Group 2 received 20 ml of 0.5% ropivacaine injected peri-incisionally with five manual inflations of the lungs with a positive-pressure ventilation of 40 cmH2O at the end of surgery.The last inflation was held for 5 seconds.The intensity of postoperative incisional and shoulder pain was evaluated using a numerical rating scale at 0,2,4,8,12,24 and 48 hours postoperatively by an independent blinded anaesthesiologist.Tramadol was given postoperatively for analgesia.Results Compared with group 1,incisional ropivacaine infiltration combined with pulmonary recruitment manoeuvre significantly reduced dynamic pain at 0 hour,4 hours,and 24 hours postoperatively (4.1 ± 2.2 vs.2.1 ± 1.9,P=0.002;2.7 ± 2.7 vs.1.2 ± 1.3,P=0.035; and 3.5 ± 2.1 vs.2.1 ± 1.8,P=0.03,respectively).Static incisional pain was significantly relieved at 0 hour,2 hours,and 24 hours postoperatively (3.1 ± 1.7 vs.1.6 ± 1.3,P=0.001; 1.4 ± 1.3 vs.0.5 ± 0.8,P=0.012;and 2.3 ± 1.9 vs.1.0 ± 1.5,P=0.038,respectively).Group 2 had more patients without shoulder pain (P<0.05) and fewer requiring tramadol (P<0.05).Conclusion Ropivacaine with pulmonary recruitment manoeuvre provided simple and effective pain relief after diagnostic hysteroscopy and laparoscopy. 展开更多
关键词 ANALGESIA postoperative care ROPIVACAINE local anaesthesia pulmonary recruitment manoeuvre
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A NUMERICAL STUDY ON A SIMPLIFIED TAIL MODEL FOR TURNING FISH IN C-START 被引量:3
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作者 YANG Yan TONG Bing-gang 《Journal of Hydrodynamics》 SCIE EI CSCD 2006年第2期135-142,共8页
Most freshwater fish are good at turning manoeuvres. A simulated fish tail model was numerically investigated and discussed in detail. This study deals with unsteady forces and moment exerted on the fish tail-fin in a... Most freshwater fish are good at turning manoeuvres. A simulated fish tail model was numerically investigated and discussed in detail. This study deals with unsteady forces and moment exerted on the fish tail-fin in an initial sideways stroke and a subsequent return stroke motion, and visualizes the flow fields and vortex structures, in order to explore the flow control mechanism of the typical turning motion of fish. Further discussion on fluid dynamic consequences corresponding to two different bending forms of fish tail-fins in its C-start is given. The two-dimensional unsteady incompressible Navier-Stokes equations are solved with a developed pseudo-compressibility method to simulate the flow around the fish tail-fin. The computed results and the comparison with experiments indicate that (1) fish performs a turning motion of its body using the impulsive moment produced by the to-and-fro stroke, and each stage of the process exhibits its specific hydrodynamic characteristic, (2) fishes adopt two forms of tail-tip bend (single bend and double bend) to accomplish a C-start turning manoeuvre, in dependence of their physical situations and natural environments, (3) fish can control its turning motion by modulating some key kinematic parameters. 展开更多
关键词 fish swimming turning manoeuvre C-start tail fin locomotion 2D Navier-Stokes equations CFD physical mechanism optimal control
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Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques 被引量:3
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作者 TRAN KHANH Toan OUAHSINE Abdellatif +1 位作者 NACEUR Hakim EL WASSIFI Karima 《Journal of Hydrodynamics》 SCIE EI CSCD 2013年第5期788-804,共17页
In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming (MP) techniques is proposed. The... In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming (MP) techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories. 展开更多
关键词 ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming
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Reducing shoulder dislocation without anaesthesia or assistant:Validation of a new reduction manoeuvre 被引量:1
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作者 Rashid Anjum Subodh Pathak +4 位作者 Atul Rai Sharma Jatin Aggarwal Aryan Sharma Vineet Pruthi Anil Kumar Chaudhary 《Chinese Journal of Traumatology》 CAS CSCD 2019年第5期274-277,共4页
Purpose:Shoulder dislocation comprises 60%of all major joint dislocations worldwide and a number of reduction techniques are described in the literature w让h varying degrees of success.The description of a large numbe... Purpose:Shoulder dislocation comprises 60%of all major joint dislocations worldwide and a number of reduction techniques are described in the literature w让h varying degrees of success.The description of a large number of techniques speaks for itself that no method is effective all the times and one should be acquainted with more than one technique.An ideal method of reduction should be simple,easily reproducible,relatively painless that can be performed unassisted without sedation or anaesthesia w让h minimal or no further complications.We report our results of using a novel method of anterior shoulder reduction described recently in the literature that claims to fulfil most of the characteristics of an ideal method if not all.Methods:This prospective study was conducted in a tertiary care centre.All the cases of primary anterior shoulder dislocation presenting within three days of injury without any associated fracture or spine trauma with or without greater tuberosity fracture were included.The reduction was done using a novel method by orthopaedic residents in all cases.The need for a second reduction attempt or anaesthesia was considered a treatment failure.Time taken for reduction,pain felt during reduction and complications if any were noted.Results:There were 47(77.04%)males and 14(22.95%)females with a mean age of(37.04±12.63)years.The new technique was effective in locating a shoulder dislocation on the first attempt in 58 of the 61 dislocated shoulders(95.08%).The remaining three shoulders were reduced on second attempt by the same technique.Sedative,pre-medication or anaesthesia was not used in any case.The average time taken for the shoulder reductio n was(130.5±25.8)sec onds and con fide nee interval(95%)124-137 s.Iatrogenic complications were not seen in any of the patients.Conclusion:This relatively painless technique of shoulder reduction is easy to acquire and practice in emergency department.The advantages of this manoeuvre and its associated safety may justly lead surgeons to select it as their primary method for reduction of anterior shoulder dislocations. 展开更多
关键词 SHOULDER DISLOCATION EXTERNAL ROTATION manoeuvre Prakash's manoeuvre
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Risk assessment of LNG and FLNG vessels during manoeuvring in open sea 被引量:3
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作者 Nagi Abdussamie Mohamed Daboos +2 位作者 Ismail Elferjani Chai Shuhong Abdusalam Alaktiwi 《Journal of Ocean Engineering and Science》 SCIE 2018年第1期56-66,共11页
Manoeuvring of a Liquefied Natural Gas(LNG)carrier in open sea at Floating LNG(FLNG)terminals can be associated with several operational risks of potential consequences to human safety,the environment and economy.In t... Manoeuvring of a Liquefied Natural Gas(LNG)carrier in open sea at Floating LNG(FLNG)terminals can be associated with several operational risks of potential consequences to human safety,the environment and economy.In this paper,a fuzzy set approach was developed to handle the uncertainty in expert opinions commonly used for qualitative risk assessment studies such as the risk matrix.Risk parameters were modelled using a number of fuzzy sets,and a fuzzy risk value was calculated for several hazardous scenarios at different phases during ship berthing operations.The calculated fuzzy risk values were found to be consistent with the results of the risk matrix technique.©2017 Shanghai Jiaotong University.Published by Elsevier B.V. 展开更多
关键词 Offshore gas export Floating gas terminals Hazards during ship manoeuvring Fuzzy logic
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Integrated guidance and control with input saturation and disturbance observer 被引量:1
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作者 Wangkui Liu Yiyin Wei +1 位作者 Guangren Duan Mingzhe Hou 《Journal of Control and Decision》 EI 2018年第3期277-299,共23页
In presence of input saturation,a novel integrated guidance and control(IGC)law based on the backstepping technique is proposed for missiles attacking manoeuvring target in this paper.A modified saturation function an... In presence of input saturation,a novel integrated guidance and control(IGC)law based on the backstepping technique is proposed for missiles attacking manoeuvring target in this paper.A modified saturation function and an auxiliary system are proposed to deal with the input saturation.The state of the auxiliary system is used in the IGC law design process and stability analysis.Considering the uncertainties caused by target manoeuvres,model errors and variation of the aerodynamic parameters,disturbance observers which converge in finite time are introduced to estimate and compensate them.Based on the Lyapunov theory,the detailed stability analysis of the closedloop system is presented.The non-linear numerical simulations are presented to illustrate the effectiveness of the proposed IGC law. 展开更多
关键词 Integrated guidance and control(IGC) input saturation BACKSTEPPING disturbance observer manoeuvring target
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Multiple Robots Formation Manoeuvring and Collision Avoidance Strategy 被引量:1
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作者 Ao-Lei Yang Wasif Naeem +2 位作者 Min-Rui Fei Li Liu Xiao-Wei Tu 《International Journal of Automation and computing》 EI CSCD 2017年第6期696-705,共10页
This paper presents a multiple robots formation manoeuvring and its collision avoidance strategy. The direction priority sequential selection algorithm is employed to achieve the raw path, and a new algorithm is then ... This paper presents a multiple robots formation manoeuvring and its collision avoidance strategy. The direction priority sequential selection algorithm is employed to achieve the raw path, and a new algorithm is then proposed to calculate the turning-compliant waypoints supporting the multi-robot formation manoeuvre. The collision avoidance strategy based on the formation control is presented to translate the collision avoidance problem into the stability problem of the formation. The extension-decomposition-aggregation scheme is next applied to solve the formation control problem and subsequently achieve the collision avoidance during the formation manoeuvre. Simulation study finally shows that the collision avoidance problem can be conveniently solved if the stability of the constructed formation including unidentified objects can be satisfied. 展开更多
关键词 Path planning formation control manoeuvring waypoints line-of-sight collision avoidance
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