Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination ...Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination of the type of sluice,this paper researches the difficult points of design advance,through researching the motion locus & stress coundition of linked tetra shaft system.The writer will build up the mathmatical model and handle it with the computer.Thus,we can achieve the modern desing on the basis of the software of linked tetra shaft system development.展开更多
In this paper,the y-component of magnetic field line curvature in the plasma sheet was analyzed,and two kinds of shear structures of the flapping current sheet were found,i.e.symmetric and antisymmetric.The alternatin...In this paper,the y-component of magnetic field line curvature in the plasma sheet was analyzed,and two kinds of shear structures of the flapping current sheet were found,i.e.symmetric and antisymmetric.The alternating bending orientations of the guiding field are exactly corresponding to alternating north-south asymmetries of the bouncing ion population in the sheet center.Those alternating asymmetric plasma sources consequently induce the current sheet flapping motion as a driver.In addition,a substantial particle population with downward motion was observed in the center of a bifurcated current sheet.This population is identified as the quasi-adiabatic particles,and provides a net current opposite to the conventional cross-tail current.展开更多
2019年2月13日至17日,一年一度的北美颅底外科协会(NASBS)年会在美国召开,重庆医科大学附属第一医院神经外科杨刚主任医师作为中国参会的五名代表之一受邀出席并发表演讲,由他首创并命名的"In Situ Bone Flap"(原位骨瓣)在内...2019年2月13日至17日,一年一度的北美颅底外科协会(NASBS)年会在美国召开,重庆医科大学附属第一医院神经外科杨刚主任医师作为中国参会的五名代表之一受邀出席并发表演讲,由他首创并命名的"In Situ Bone Flap"(原位骨瓣)在内镜下扩大经鼻入路术后颅底重建方面的经验轰动全场。展开更多
Micro Aerial Vehicles(MAVs) are the smallest artificial aircraft.Most of the flapping wings MAVs are powered by electric motors of various capacities.We report in this paper the application of piezoelectric actuators ...Micro Aerial Vehicles(MAVs) are the smallest artificial aircraft.Most of the flapping wings MAVs are powered by electric motors of various capacities.We report in this paper the application of piezoelectric actuators as power system for a flapping wing MAV using a compliant displacement amplification mechanism.The actuator used for this application is a pre-stressed cut piece of TH-7R type Thunder actuator.A two-bar compliant mechanism with two flexures has been developed to convert the linear displacement into angular movement and amplification.The specimens were made from carbon fiber links and nylon flexures.We also proposed to use the product of frequency(F) and tip displacement(D), F * D as a criteria for the characterization of an amplifying mechanism.The best specimen according to this criterion is obtained for a 5mm length flexure specimen made of three layers of nylon.The F*D value obtained for this specimen was(0.58) Hz.m.ANSYS finite element analysis results for different flexural thickness and lengths were obtained and have been compared to the experimental results.The effect of both the thickness and length of the flexure on a particular arrangement has been discussed.展开更多
目的·比较分析机器人与腹腔镜辅助近端胃切除联合双肌瓣吻合术在治疗早期胃上部癌中的安全性及近期效果。方法·采用回顾性队列研究方法,分析2023年9月至2024年3月于上海交通大学医学院附属仁济医院胃肠外科行近端胃切除联合...目的·比较分析机器人与腹腔镜辅助近端胃切除联合双肌瓣吻合术在治疗早期胃上部癌中的安全性及近期效果。方法·采用回顾性队列研究方法,分析2023年9月至2024年3月于上海交通大学医学院附属仁济医院胃肠外科行近端胃切除联合双肌瓣吻合进行消化道重建的31例早期胃癌患者临床病理资料。根据手术方式不同,将患者分为机器人辅助手术组(机器人组,20例)和腹腔镜辅助手术组(腹腔镜组,11例)。比较2组患者的一般临床资料、术中情况及术后恢复情况。术后6个月随访时,行上消化道造影和食管胃镜检查,判断是否有吻合口狭窄及反流性食管炎;同时,使用欧洲癌症研究与治疗组织(European Organization for Research and Treatment of Cancer,EORTC)的胃癌特异模块量表(Quality of Life Questionnaire-Stomach 22,QLQ-STO22)评估患者的生活质量。结果·2组患者的一般资料,包括性别、年龄、术前合并症、美国麻醉医师协会(American Society of Anesthesiologists,ASA)分级、Siewert分型以及肿瘤的病理分期,差异均无统计学意义(均P>0.05)。2组患者均顺利完成手术,无中转开腹。机器人组的胃食管吻合时间较腹腔镜组显著缩短[(31.09±8.23)min vs(43.73±8.83)min,P<0.001],而术中及术后各项指标,包括手术时间、术中失血量、淋巴结清扫数、术后胃管留置时间、术后流质饮食开始时间、术后住院天数以及术后并发症发生率在2组之间差异均无统计学意义(均P>0.05)。术后6个月随访共有30例患者完成(其中机器人组失访1例)。上消化道造影及食管胃镜检查结果显示,仅腹腔镜组1例患者出现吻合口狭窄,机器人组出现A级和B级反流性食管炎各1例,腹腔镜组出现B级反流性食管炎1例。2组反流性食管炎和吻合口狭窄发生率差异均无统计学意义(均P>0.05)。EORTC QLQ-STO22评分结果显示,机器人组在吞咽困难、胃食管反流、饮食受限3个维度的评分,以及量表总分均显著低于腹腔镜组(均P<0.05)。结论·机器人辅助近端胃切除联合双肌瓣吻合手术安全可行,术中吻合时间更短,且在术后功能恢复和患者生活质量提升方面具有潜在优势。展开更多
文摘Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination of the type of sluice,this paper researches the difficult points of design advance,through researching the motion locus & stress coundition of linked tetra shaft system.The writer will build up the mathmatical model and handle it with the computer.Thus,we can achieve the modern desing on the basis of the software of linked tetra shaft system development.
基金the National Natural Science Foundation of China(41174144,40974098)。
文摘In this paper,the y-component of magnetic field line curvature in the plasma sheet was analyzed,and two kinds of shear structures of the flapping current sheet were found,i.e.symmetric and antisymmetric.The alternating bending orientations of the guiding field are exactly corresponding to alternating north-south asymmetries of the bouncing ion population in the sheet center.Those alternating asymmetric plasma sources consequently induce the current sheet flapping motion as a driver.In addition,a substantial particle population with downward motion was observed in the center of a bifurcated current sheet.This population is identified as the quasi-adiabatic particles,and provides a net current opposite to the conventional cross-tail current.
文摘Micro Aerial Vehicles(MAVs) are the smallest artificial aircraft.Most of the flapping wings MAVs are powered by electric motors of various capacities.We report in this paper the application of piezoelectric actuators as power system for a flapping wing MAV using a compliant displacement amplification mechanism.The actuator used for this application is a pre-stressed cut piece of TH-7R type Thunder actuator.A two-bar compliant mechanism with two flexures has been developed to convert the linear displacement into angular movement and amplification.The specimens were made from carbon fiber links and nylon flexures.We also proposed to use the product of frequency(F) and tip displacement(D), F * D as a criteria for the characterization of an amplifying mechanism.The best specimen according to this criterion is obtained for a 5mm length flexure specimen made of three layers of nylon.The F*D value obtained for this specimen was(0.58) Hz.m.ANSYS finite element analysis results for different flexural thickness and lengths were obtained and have been compared to the experimental results.The effect of both the thickness and length of the flexure on a particular arrangement has been discussed.
文摘目的·比较分析机器人与腹腔镜辅助近端胃切除联合双肌瓣吻合术在治疗早期胃上部癌中的安全性及近期效果。方法·采用回顾性队列研究方法,分析2023年9月至2024年3月于上海交通大学医学院附属仁济医院胃肠外科行近端胃切除联合双肌瓣吻合进行消化道重建的31例早期胃癌患者临床病理资料。根据手术方式不同,将患者分为机器人辅助手术组(机器人组,20例)和腹腔镜辅助手术组(腹腔镜组,11例)。比较2组患者的一般临床资料、术中情况及术后恢复情况。术后6个月随访时,行上消化道造影和食管胃镜检查,判断是否有吻合口狭窄及反流性食管炎;同时,使用欧洲癌症研究与治疗组织(European Organization for Research and Treatment of Cancer,EORTC)的胃癌特异模块量表(Quality of Life Questionnaire-Stomach 22,QLQ-STO22)评估患者的生活质量。结果·2组患者的一般资料,包括性别、年龄、术前合并症、美国麻醉医师协会(American Society of Anesthesiologists,ASA)分级、Siewert分型以及肿瘤的病理分期,差异均无统计学意义(均P>0.05)。2组患者均顺利完成手术,无中转开腹。机器人组的胃食管吻合时间较腹腔镜组显著缩短[(31.09±8.23)min vs(43.73±8.83)min,P<0.001],而术中及术后各项指标,包括手术时间、术中失血量、淋巴结清扫数、术后胃管留置时间、术后流质饮食开始时间、术后住院天数以及术后并发症发生率在2组之间差异均无统计学意义(均P>0.05)。术后6个月随访共有30例患者完成(其中机器人组失访1例)。上消化道造影及食管胃镜检查结果显示,仅腹腔镜组1例患者出现吻合口狭窄,机器人组出现A级和B级反流性食管炎各1例,腹腔镜组出现B级反流性食管炎1例。2组反流性食管炎和吻合口狭窄发生率差异均无统计学意义(均P>0.05)。EORTC QLQ-STO22评分结果显示,机器人组在吞咽困难、胃食管反流、饮食受限3个维度的评分,以及量表总分均显著低于腹腔镜组(均P<0.05)。结论·机器人辅助近端胃切除联合双肌瓣吻合手术安全可行,术中吻合时间更短,且在术后功能恢复和患者生活质量提升方面具有潜在优势。
