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悬吊术治疗重度混合痔的研究进展

国际外科学杂志 2023年第1期50卷 55-60页

作者：马钰婷郭修田上海中医药大学附属市中医医院肛肠科上海200071

重度混合痔的发病率逐年上升,其手术方式一直是肛肠科研究的重点。肛垫悬吊术依据"肛垫下移学说",将痔核和齿状线以上的黏膜缝扎、结扎或套扎,使脱垂的肛垫上移复位,既保证了手术治疗的效果,又能够最精细的保护肛管、肛门的结构和功能,... 详细信息

重度混合痔的发病率逐年上升,其手术方式一直是肛肠科研究的重点。肛垫悬吊术依据"肛垫下移学说",将痔核和齿状线以上的黏膜缝扎、结扎或套扎,使脱垂的肛垫上移复位,既保证了手术治疗的效果,又能够最精细的保护肛管、肛门的结构和功能,符合重度混合痔的微创治疗思想,逐渐广泛应用于临床。肛垫悬吊术作为一种新的术式应用于重度混合痔,尤其在重度脱垂性痔手术中具有独特优势。本文将通过分析近年来肛垫悬吊术联合吻合器痔上黏膜环切术、外剥内扎术、痔动脉结扎术、自动痔疮套扎术、硬化剂注射术、激光消融术及多项术式的手术操作要点,以期为临床医师手术治疗重度混合痔提供参考。

关键词：痔研究综述悬吊术重度混合痔

Development of a novel signal restoration algorithm to eliminate the distorted components in space charge measurement excited by femtosecond laser irradiation

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High Voltage 2024年第3期9卷 659-673页

作者： Tianrun Qi Hanwen Ren Haoyu Gao Qingmin Li Yidan ma Yiqun ma Tao Xiao State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

For the space charge measurement method with optical excitation for electrical insulation,the distortion of the excitation laser on the measurement signal and the accumulation of space charge have not been discussed *** experiment and simulation results show that three types of distorted components introduced by optical excitation can lead to distortion of the upper interface ***,the factors causing distortion of the measured signal and the formation mechanism are analysed.A virtual electrode potential compensation method and a distorted component extraction method are ***,an attenuation restoration and charge conversion correction factor is intro-duced,leading to a novel signal processing algorithm adapted to space charge optical measurement *** with the traditional algorithm,the novel algorithm has an error of less than 1%in the calculation of charge and electric field strength,with an increase in accuracy of 47.7%and 9.81%,*** applying the novel restoration algorithm,the comparison shows that the space charge accumulation does not change significantly under laser irradiation,verifying the reliability of the optical *** given algorithm can provide a theoretical and technical foundation for the realisation of the optical measurement method for space charge.

关键词： charge algorithm excitation

基于激光测距与单目视觉的微型无人机室内目标人物搜索方法研究

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中国科学：技术科学 2020年第7期50卷 971-982页

作者：高天禹马雨婷韩成哲蔡博翁睿张立宪哈尔滨工业大学航天学院哈尔滨150001 系统控制与信息处理教育部重点实验室上海200240

微型无人机一般指尺寸在10 cm以下的超小体积无人机,其载荷能力有限,无法携带高性能传感器及机载计算机,在执行自主飞行任务方面存在困难.本文在导航和识别方面提出了一种在微型无人机上装配单目相机及激光传感器实现室内目标人物搜索... 详细信息

微型无人机一般指尺寸在10 cm以下的超小体积无人机,其载荷能力有限,无法携带高性能传感器及机载计算机,在执行自主飞行任务方面存在困难.本文在导航和识别方面提出了一种在微型无人机上装配单目相机及激光传感器实现室内目标人物搜索的方案.为在含有多房间的复杂室内环境中到达目标人物所在区域,本文基于激光测距路径规划实现了微型无人机的"沿边"搜索,完成了对室内主要区域的遍历式查找.同时,设计了一种基于地面站辅助云计算,结合全卷积神经网络单目图像深度恢复与深度阈值图的路径规划方法,在激光无法正常工作时完成导航任务并优化"沿边"飞行过程中冗余的搜索路径.为检测并跟踪搜索过程中出现的目标人物,本文采用YOLOv3目标检测算法对人脸、躯干、人手等多部位进行检测,并采用剪枝化设计降低了其检测耗时.为确保目标面部特征丢失时仍能对其进行持续跟踪,本文提出了一种人脸识别与躯干检测切换式的跟踪方案,同时能通过检测到的手部位置信息,对目标的意图进行实时判断.经实验比对,本文的算法有效缩短了搜索过程的飞行距离,提升了目标追踪的成功率.

关键词：微型无人机室内导航深度恢复深度阈值图目标识别跟踪

Take Every Step Firmly with Sharp Eyes

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Chinese Journal of Chemistry 2024年第10期42卷 1065-1066页

作者： Shengming ma Chinese Journal of Chemistry

Chinese Journal of Chemistry(CJC)is committed to becoming a prominent international journal for chemistry and the related *** are working very hard towards this *** offers a diverse range of manuscript types,including... 详细信息

关键词： journal becoming diverse

Impact of Polymer matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

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Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： Yu Wu Xin Cheng Huan Hu Shui Hu Zhimin ma Zhiyong ma Beijing Advanced Innovation Center for Soft matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention ***,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) ***-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),*** the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@Pma-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds ***,under stretching,external force can tune the emission of the PhMz=2A@Pma-2-EA sample from K* to E* *** external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating *** calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/***,PhMz-NH2-OH@PU and PhMz=2A@Pma-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to *** study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

A rigorous real-time acoustic positioning method for ocean bottom seismic exploration

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Satellite Navigation 2024年第1期5卷 168-190页

作者： Jinye ma Shouchuan Fang Jianhu Zhao School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China Institute of marine Science and Technology Wuhan UniversityWuhan430079China Surveying Service Center BGP Inc.CNPCZhuozhou072751HebeiChina

The conventional technique for positioning seafloor geophones in ocean bottom seismic exploration encounters several challenges,including the significant impact of outliers on positioning results,underutilization of high-precision observations,and low efficiency in real-time data *** issues inevitably affect the quality of seismic exploration *** address these challenges and enhance the accuracy of geophone positioning,this paper proposes a rigorous real-time acoustic positioning method for geophones based on sequential adjustment and Baarda's outlier detection *** proposed method comprises three key steps:grouping the original acoustic observations,constructing the intra-group acoustic positioning model,and synthesizing the positioning results across the different *** validity and practicality of this approach are confirmed through a simulation experiment as well as the field experiment conducted in the Bohai Sea,*** results demonstrate that the proposed method effectively eliminates outliers in the original observations and maximizes the utilization of high-quality *** to traditional acoustic positioning methods,it significantly reduces positioning errors from meters to decimeters,and in some cases can achieve centimeter-level *** the sound velocity profile in the operating sea area is measured,the method can attain the posterior standard deviation at the millimeter level and positioning errors within 10 *** the sound velocity profile is unknown,the method can achieve the posterior standard deviation at centimeter-level and positioning errors of approximately 20 cm.

关键词： Ocean bottom seismic exploration Geophone positioning Acoustic positioning method Sequential adjustment Outlier detection

L^(*)—An index for evaluating long range performance of autonomous underwater vehicles(AUVs)

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Friction 2024年第10期12卷 2205-2221页

作者： manfu ZHU Liran ma Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Autonomous underwater vehicles(AUVs)have various applications in both military and civilian fields.A wider operation area and more complex tasks require better overall range performance of ***,until recently,there have been few unified criteria for evaluating the range performance of *** the present work,a unified range index,i.e.,L^(*),considering the cruising speed,the sailing distance,and the volume of an AUV,is proposed for the first time,which can overcome the shortcomings of previous criteria using merely one single parameter,and provide a uniform criterion for the overall range performance of various *** constructing the expression of the L^(*)index,the relevant data of 49 AUVs from 12 countries worldwide have been collected,and the characteristics of the L^(*)range index in different countries and different categories were compared and ***,by analyzing the complex factors affecting the range index,methods to enhance the L^(*)range index value,such as efficiency enhancement and drag reduction,have been introduced and *** this condition,the work proposes a unified and scientific criterion for evaluating the range performance of AUVs for the first time,provides valuable theoretical insight for the development of AUVs with higher performance,and then arouses more attention to the application of the cutting-edge superlubricity technology to the field of underwater vehicles,which might greatly help to accelerate the coming of the era of the superlubricitive engineering.

关键词： autonomous underwater vehicles(AUVs) range performance range index superlubricity drag reduction

A Parameter Adaptive Method for Image Smoothing

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Tsinghua Science and Technology 2024年第4期29卷 1138-1151页

作者： Suwei Wang Xiang ma Xuemei Li School of Computer Science and Technology Shandong UniversityJinan 250101China School of Software Shandong UniversityJinan 250101China

Edge is the key information in the process of image smoothing. Some edges, especially the weak edges, are difficult to maintain, which result in the local area being over-smoothed. For the protection of weak edges, we propose an image smoothing algorithm based on global sparse structure and parameter adaptation. The algorithm decomposes the image into high frequency and low frequency part based on global sparse structure. The low frequency part contains less texture information which is relatively easy to smoothen. The high frequency part is more sensitive to edge information so it is more suitable for the selection of smoothing parameters. To reduce the computational complexity and improve the effect, we propose a bicubic polynomial fitting method to fit all the sample values into a surface. Finally, we use Alternating Direction Method of Multipliers (ADMM) to unify the whole algorithm and obtain the smoothed results by iterative optimization. Compared with traditional methods and deep learning methods, as well as the application tasks of edge extraction, image abstraction, pseudo-boundary removal, and image enhancement, it shows that our algorithm can preserve the local weak edge of the image more effectively, and the visual effect of smoothed results is better.

关键词： image smoothing parameter adaptation bicubic interpolation polynomial fitting

Bionic soft robotic gripper with feedback control for adaptive grasping and capturing applications

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Frontiers of Mechanical Engineering 2024年第1期19卷 129-148页

作者： Tingke WU Zhuyong LIU Ziqi ma Boyang WANG Daolin ma Hexi YU Department of Engineering Mechanics School of Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory of Hydrodynamics Shanghai Jiao Tong UniversityShanghai 200240China

Robots are playing an increasingly important role in engineering *** robots have promising applications in several fields due to their inherent advantages of compliance,low density,and soft interactions.A soft gripper based on bio-inspiration is proposed in this *** analyze the cushioning and energy absorption mechanism of human fingertips in detail and provide insights for designing a soft gripper with a variable stiffness *** investigate the grasping modes through a large deformation modeling approach,which is verified through *** characteristics of the three grasping modes are quantified through testing and can provide guidance for robotics ***,the adaptability of the soft gripper is verified by grasping multi-scale and extremely soft ***,a cushioning model of the soft gripper is proposed,and the effectiveness of cushioning is verified by grasping extremely sharp objects and living ***,we validate the advantages of the variable stiffness of the soft gripper,and the results show that the soft robot can robustly complete assemblies with a gap of only 0.1 *** to the unstructured nature of the engineering environment,the soft gripper can be applied in complex environments based on the abovementioned experimental ***,we design the soft robotics system with feedback capture based on the inspiration of human catching *** feasibility of engineering applications is initially verified through fast capture experiments on moving *** design concept of this robot can provide new insights for bionic machinery.

关键词： soft bionic gripper variable stiffness structure large deformation modeling feedback control soft robotic system