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基于多尺度形态滤波和递归求差的冲击特征自适应分离方法

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振动与冲击 2024年第5期43卷 149-158页

作者：和丹权伟汤明军刘晖西安工程大学机电工程学院西安710048 西安市现代智能纺织装备重点实验室西安710600 西安交通大学机械工程学院西安710049

针对故障诊断中的耦合冲击特征提取和分离难题,提出了一种基于多尺度形态滤波(multiscale morphological filtering, MMF)和递归求差的冲击特征自适应提取与分离方法。首先,利用能量幅值(energy amplitude, EA)指标和频响特性分析,从典... 详细信息

针对故障诊断中的耦合冲击特征提取和分离难题,提出了一种基于多尺度形态滤波(multiscale morphological filtering, MMF)和递归求差的冲击特征自适应提取与分离方法。首先,利用能量幅值(energy amplitude, EA)指标和频响特性分析,从典型组合算子中筛选出适合冲击特征分离的组合形态滤波-帽变换(combination morphological filter-hat transform, CMFH)算子;其次,利用CMFH形态学算子和加权谐噪比(weighted harmonic to noise ratio, WHNR)指标实现周期性冲击特征提取;然后,利用求差增强技术(strengthen operate subtract operate, SOSO)抑制谐波干扰和白噪声,进一步增强周期性冲击特征;最后,通过迭代求差思想构造循环滤波器,对周期性冲击特征进行多尺度提取与分离。仿真数据和牵引电机轴承故障数据分析结果表明,该方法在随机冲击、谐波干扰下的周期性冲击提取能力优于最大二阶循环平稳盲解卷积(maximum second order cyclostationary blind deconvolution, CYCBD)方法和经典谱峭度方法。

关键词：多尺度形态滤波(MMF) 冲击特征加权谐噪比(WHNR) 复合故障

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基于华中8型数控系统的段差磨削软件开发

机床与液压 2024年第2期52卷 95-100页

作者：汤明俊李健程铖柴佳镔许竞博武汉华中数控有限公司湖北武汉430068

采用华中8型数控系统为开发平台,以段差磨削工艺为研究对象,开发了段差磨削软件系统。该软件在Qt Creator跨平台开发框架下进行UI应用程序的开发,基于华中HNC-808D数控系统的二次开发体系架构,利用API接口进行软件功能开发;同时以小线... 详细信息

采用华中8型数控系统为开发平台,以段差磨削工艺为研究对象,开发了段差磨削软件系统。该软件在Qt Creator跨平台开发框架下进行UI应用程序的开发,基于华中HNC-808D数控系统的二次开发体系架构,利用API接口进行软件功能开发;同时以小线段的方式生成加工宏程序,以丝锥磨削削为载体,实现了段差精密磨削加工。结果表明:该软件加工精度达到实际需求,加工效率大大提升,在段差磨削领域中提供了一套国产系统应用实例。

关键词：段差磨削小线段程序 HNC-808D数控系统二次开发

国产新型静脉射频闭合治疗系统与进口系统应用效果的随机对照研究

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中华外科杂志 2024年第3期62卷 223-228页

作者：唐明珺周玲羽贾晓坚吴劲进楼炎波金明娟朱越锋浙江大学医学院附属第四医院血管外科义乌322000 浙江大学医学院公共卫生学院杭州310000 浙江大学医学院附属邵逸夫医院血管外科杭州310016

目的比较国产新型静脉射频闭合治疗系统与进口系统治疗原发性下肢静脉曲张的应用效果。方法本研究为单中心、前瞻性、非劣效性随机对照试验。纳入2021年1月至2022年1月浙江大学医学院附属第四医院血管外科收治的符合纳入和排除标准的原... 详细信息

目的比较国产新型静脉射频闭合治疗系统与进口系统治疗原发性下肢静脉曲张的应用效果。方法本研究为单中心、前瞻性、非劣效性随机对照试验。纳入2021年1月至2022年1月浙江大学医学院附属第四医院血管外科收治的符合纳入和排除标准的原发性下肢静脉曲张患者,按1∶1随机分为两组,分别接受国产新型静脉射频闭合治疗系统和进口静脉射频闭合治疗系统治疗。对两组的技术成功率、系统操作性能、术后6个月内的不良事件和严重不良事件(SAE)发生率、术后6个月目标静脉闭合率等进行比较。定量资料的比较采用Mann-Whitney U检验,分类资料的比较采用χ^(2)检验、Fisher确切概率法或非劣效性检验。结果研究共纳入80例患者,试验组41例,对照组39例。其中男性27例,女性53例;年龄[M(IQR)]55(23)岁(范围:40~78岁);左下肢48例,右下肢32例。两组技术成功率均为100%,术中均未出现系统操作故障。试验组和对照组术后6个月内不良事件发生率[58.5%(24/41)比61.5%(24/39),χ^(2)=0.075,P=0.784]、SAE发生率[7.3%(3/41)比5.1%(2/39),χ^(2)=0.163,P=0.686]的差异均无统计学意义。两组各发生1例器械相关不良事件,试验组1例患者术后发生静脉内热致血栓,口服利伐沙班片后痊愈;对照组1例术后右大腿上段疼痛1 d余,外用镇痛、消肿药物后痊愈。未发生器械相关SAE。试验组术后6个月血管闭合率为100%(38/38),对照组为97.4%(37/38),试验组与对照组术后6个月目标静脉闭合率差值为2.6%(95%CI:-3.19~8.45,Z=4.865,P<0.01),差值的95%CI低限大于非劣效界值-10.0%。结论国产新型静脉射频闭合治疗系统在原发性下肢静脉曲张患者中的早期应用效果不劣于进口静脉射频闭合治疗系统。

关键词：静脉曲张下肢射频消融应用效果国产静脉射频闭合治疗系统

Synthesis of novel superhard materials under ultrahigh pressure

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Chinese Science Bulletin 2014年第36期59卷 5251-5257页

作者： Chao Xu Duanwei He Haikuo Wang Wendan Wang mingjun tang Pei Wang Institute of Atomic and Molecular Physics Sichuan University

Superhard materials are solids whose Vickers hardness is beyond 40 GPa. They have wide applications in industry such as cutting and polishing tools, wear-resistant coatings. Most preparations of superhard materials are conducted under extreme pressure and temperature conditions, not only for scientific investigations, but also for the practical applications. In this paper, we would introduce the recent progress on the design and preparations of novel superhard materials, mainly on nanopolycrystalline diamond, B–C–N superhard solid solutions, and cubic-Si3N4/diamond nanocomposites prepared under ultrahigh pressure and high temperature(HPHT), using multi-anvil apparatus based on the hinged-type cubic press. Bulk materials of all these superhard phases have been successfully synthesized and are systematically tested. We emphasize that ultra-HPHT method plays an important role in the scientific research and industrial production of superhard materials. It provides the driving forces for the light elements forming novel superhard phases as well as the way for sintering high-density nanosuperhard materials.

关键词：超高压合成超硬材料立方氮化硅高温高压法纳米复合材料工业生产维氏硬度抛光工具

LM-2D Successfully Launches 4 Satellites into Orbit on One Launch

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Aerospace China 2020年第1期21卷 58-59页

作者： tang mingjun China Space News

At 10:53 Beiing time on Jatuary 15,a LM-2D launch vehicle lifted off from the Tiyuan Satellite Launch Center,suc-cessfully launching the jlin-|wide-swath 01 satellite(ilin-1 KF 01)and 3 other small satlites into their preset *** the jlin-I KF 01 satelite,the 3 other small stllites piggybacked on-board the carrier rocket were the Tianqi 5 for Internet of Things developed by Shanghai ASES Spacelight Technology Co.,Ltd,a wholly-owned subsidiary of Aerospace System Engineering Shanghai under the Shanghai Academy of Space-flight Technology,plus the NewSat-7 and NewSat-8 low-Earth orbit remote sensing stllites,which were designed,manufactured and tested by Satellogic based in Argentina.

关键词： Launch lift elite

A Web-Based Approach for the Efficient Management of Massive Multi-source 3D Models

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Journal of Geodesy and Geoinformation Science 2024年第3期7卷 24-41页

作者： ZHAO Qiansheng tang Ruibing PENG mingjun GUO Mingwu School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Wuhan Geomatics Institute Wuhan 430022China

Effectively managing extensive,multi-source,and multi-level real-scene 3D models for responsive retrieval scheduling and rapid visualization in the Web environment is a significant challenge in the current development of real-scene 3D applications in *** this paper,we address this challenge by reorganizing spatial and temporal information into a 3D geospatial *** introduces the Global 3D Geocoding System(G_(3)DGS),leveraging neighborhood similarity and uniqueness for efficient storage,retrieval,updating,and scheduling of these models.A combination of G_(3)DGS and non-relational databases is implemented,enhancing data storage scalability and ***,a model detail management scheduling strategy(TLOD)based on G_(3)DGS and an importance factor T is *** with mainstream commercial and open-source platforms,this method significantly enhances the loadable capacity of massive multi-source real-scene 3D models in the Web environment by 33%,improves browsing efficiency by 48%,and accelerates invocation speed by 40%.

关键词： massive multi-source real-scene 3D model non-relational database global 3D geocoding system importance factor massive model management

Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process

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Defence Technology（防务技术） 2024年第2期32卷 262-270页

作者： Enfa Fu mingjun Yi Qianling Liu Zhenggang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094People's Republic of China

Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant ***,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted *** study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during *** drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based ***,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent *** outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants.

关键词： Nitrocellulose-based propellants Solvent transport dynamics Mechanical properties Drying kinetics Effective solvent diffusion coefficient

Research Progress on Bionic Water Strider Robots

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Journal of Bionic Engineering 2024年第2期21卷 635-652页

作者： Jianhao Liu mingjun Shen Ziqiang Ma Xinping Zhou School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Biological water striders have advantages such as flexible movement,low disturbance to the water surface,and low *** have developed a large number of biomimetic water strider robots based on their movement mechanism,which have broad application prospects in water quality testing,water surface reconnaissance,and *** article mainly reviews the research progress of biomimetic water strider ***,the biological and kinematic characteristics of water striders are outlined,and some mechanical parameters of biological water striders are *** basic equations of water strider movement are then ***,an overview is given of the past and current work on skating and jumping movements of biomimetic water strider robots based on surface tension and water pressure *** on the current research status of biomimetic water strider robots,the shortcomings of current research on biomimetic water striders are summarized,and the future development of biomimetic water strider robots is *** article provides new insights for the design of biomimetic water strider robots.

关键词： Bionics Water strider Robot Motion of robots on water surface

佛教逻辑学的论辩解释与认知解释——陈那、法称与因明

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逻辑学研究 2021年第1期14卷 82-100页

作者：汤铭钧复旦大学哲学学院宗教学系

佛教逻辑有别于西方形式逻辑的一项重要特征,在于对论证前提为真的强调,并在此基础上提出了著名的"因三相"理论。论证前提的真,在陈那著作中又被理解为辩论主体将该前提确定为真。这种"确定"体现为文献中对"极成"(prasiddha)、"成"(sidd... 详细信息

佛教逻辑有别于西方形式逻辑的一项重要特征,在于对论证前提为真的强调,并在此基础上提出了著名的"因三相"理论。论证前提的真,在陈那著作中又被理解为辩论主体将该前提确定为真。这种"确定"体现为文献中对"极成"(prasiddha)、"成"(siddha)、"决定"(ni?cita)、"见"(d???a)、"已知"(vidita)的强调。这些表达辩论者认知状态的词汇,皆可概括为佛教逻辑中的"认知算子"(epistemic operator)。本文通过研究东亚因明与法称两个传统对陈那《正理门论》中"决定同许"的理论设定的不同解释,说明因明传统在陈那奠定的方向上,进一步采取了"论辩解释"(dialectic interpretation),将"确定为真"解释为在辩论的情境中为辩论的双方承认为真(共许、同许)。法称《释量论自注》对陈那"决定同许"的解释,则表明由他开启的传统在陈那的基础上,进一步采取了"认知解释"(epistemic interpretation),将"确定为真"解释为在认识论的意义上得到确定(ni?cita/ni?caya,决定),即为有效认知的手段(量)所证成。这是因明传统与法称传统的一项根本差异。因明传统对辩论术的关注,极有可能反映了法称以前印度学界对陈那思想的诠释路径。

关键词：认知算子陈那法称因明佛教逻辑