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多信道无线Mesh网络中一种改进的DSDV路由算法 预览
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作者 唐建清 邹国霞 《数字技术与应用》 2019年第7期122-124,共3页
本文针对无线Mesh网络主干网部署变动少的特性,设计了多信道无线Mesh网络中DSDV路由算法,利用OMNeT++5.3对DSDV路由原算法和改进后算法进行仿真对比,在仿真时间、消息数量、网络传输参数相同情况下,主要从丢包数量情况进行统计,仿真结... 本文针对无线Mesh网络主干网部署变动少的特性,设计了多信道无线Mesh网络中DSDV路由算法,利用OMNeT++5.3对DSDV路由原算法和改进后算法进行仿真对比,在仿真时间、消息数量、网络传输参数相同情况下,主要从丢包数量情况进行统计,仿真结果证明当消息都发往同一个地址时,算法改进前后没有太大差别,当消息发往全网任意一个地址时,改进后的多信道DSDV算法丢包量明显少于改进前的DSDV算法,而且在同等条件下,消息缓存容量大的丢包量会明显减少。 展开更多
关键词 MESH DSDV路由 多信道 丢包量
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基于无线Mesh网络技术智能家居方案的研究 预览
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作者 陈静 《电子产品可靠性与环境试验》 2019年第A01期193-197,共5页
针对目前智能家居方案组网设计复杂、后台设备过多和成本过高等一系列问题,设计了一种基于无线Mesh网络技术的智能家居方案。该方案包括手机客户端、无线Mesh网关、设备控制终端和家具设备4个部分,使用到的技术包括无线Mesh网络技术和4... 针对目前智能家居方案组网设计复杂、后台设备过多和成本过高等一系列问题,设计了一种基于无线Mesh网络技术的智能家居方案。该方案包括手机客户端、无线Mesh网关、设备控制终端和家具设备4个部分,使用到的技术包括无线Mesh网络技术和4G技术,具有组网简单、成本较低和扩展设备方便等优点,能够很好地满足人们对智能家居的需求。 展开更多
关键词 智能家居 无线组网 MESH 4G
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Anping County Shangchen Wiremesh Products CO.,LTD. 预览
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《中国经贸》 2019年第15期144-145,共2页
Anping County Shangchen Wiremesh Products CO.,LTD. is found in 2010, it is a modem enterprise which set research and development,foreign trade into a whole. The head office is located in “Hometon of Wire Mesh in Chin... Anping County Shangchen Wiremesh Products CO.,LTD. is found in 2010, it is a modem enterprise which set research and development,foreign trade into a whole. The head office is located in “Hometon of Wire Mesh in China” Anping County is famous as hometown of wire mesh. Anping County Shangchen Wiremesh Products CO.,LTD. main products and sales: Gabion Mesh, Wire Mesh Fence, Perforated Metal, Welded Wire Mesh, Filter Mesh, Window Screen, Plastic Net, Filter Cartridge, Metal Basket, Barbecue Wire Mesh, Metal Cage, Fiberglass Mesh, Steel Grating, Metal Wire. Our products are widely used in industry, agriculture, cultivation, construction, transport and mining.By now we have already established friendly business relations with more than 80 countries from Southeast Asia, Europe, America, Middle East,Africa, and the sales amount and customers quadruple annually. 展开更多
关键词 Anping COUNTY Shangchen Wiremesh PRODUCTS CO. LTD. GABION MESH Wire MESH Fence
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基于逻辑传感和无线MESH的采煤机远程冗余控制系统 预览
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作者 任阳阳 《煤矿现代化》 2019年第3期125-127,129共4页
文中以电牵引采煤机远程控制的应用现状为依托,基于以太网技术、无线短距离网状网、生产中采煤机远程冗余控制Profibus系统技术结合的基础上设计了一种新型的电牵引采煤机参数化控制。通过在西安煤矿机械有限公司对该技术进行实际应用,... 文中以电牵引采煤机远程控制的应用现状为依托,基于以太网技术、无线短距离网状网、生产中采煤机远程冗余控制Profibus系统技术结合的基础上设计了一种新型的电牵引采煤机参数化控制。通过在西安煤矿机械有限公司对该技术进行实际应用,结果表明所设计的控制理论能够实现远程监控的功能。 展开更多
关键词 电牵引采煤机 以太网 MESH 远程冗余控制 参数监控
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腹腔镜下骶骨阴道固定术治疗女性盆腔脏器中重度脱垂21例 预览
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作者 李长雨 朱婷婷 +1 位作者 汪海妍 庄雅丽 《安徽医药》 CAS 2019年第7期1408-1411,共4页
目的探讨Y型聚丙烯网片腹腔镜下骶骨阴道固定术(LSC)治疗女性盆腔脏器脱垂(POP)的临床疗效及并发症。方法选取2014年3月至2017年3月安徽省妇幼保健院收治的中重度POP病人21例,均采用Y型聚丙烯网片LSC术治疗,比较手术前后客观治愈率(POP-... 目的探讨Y型聚丙烯网片腹腔镜下骶骨阴道固定术(LSC)治疗女性盆腔脏器脱垂(POP)的临床疗效及并发症。方法选取2014年3月至2017年3月安徽省妇幼保健院收治的中重度POP病人21例,均采用Y型聚丙烯网片LSC术治疗,比较手术前后客观治愈率(POP-Q评分量表)、主观治愈率[盆底功能障碍性疾病症状问卷(PFDI-20)、盆底疾病生活质量影响问卷短表(PRIQ-7)、性生活质量问卷(PISQ-12)]及并发症情况。结果21例病人客观治愈率100.0%,主观治愈率90.5%。POPQ分期中C、Aa、Ap、Ba、Bp点值术后明显减小;PFDI-20评分、PFIQ-7评分术后明显减小,PISQ-12评分术后明显增加,整体差异及各时点与术前比较,均差异有统计学意义(P<0.01)。术后随访1年未见POP复发、补片侵蚀、肠梗阻等并发症。3例术后新发轻度压力性尿失禁(SUI),1~3月后逐渐消失。结论采用Y型聚丙烯网片LSC术治疗中重度POP的主、客观治愈率高,阴道顶端脱垂的复发率极低,术后对病人生活质量影响少,不仅可纠正中盆腔缺陷,同时也可纠正重度膀胱膨出或直肠膨出。LSC术的长期疗效仍待观察。 展开更多
关键词 盆腔脏器脱垂 腹腔镜检查 网片 骶骨悬吊
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Influence of Different Velocities on Muzzle Flow Field 预览
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作者 LI Zijie WANG Hao 《南京航空航天大学学报:英文版》 EI CSCD 2019年第1期88-97,共10页
A two-dimensional axisymmetric numerical simulation was successfully carried out on the muzzle flow field of a 300 mm-caliber counter-mass propelling gun. Based on the FLUENT software,using the finite volume method (F... A two-dimensional axisymmetric numerical simulation was successfully carried out on the muzzle flow field of a 300 mm-caliber counter-mass propelling gun. Based on the FLUENT software,using the finite volume method (FVM)and the realizable k-ε turbulence model,we adopted the holistic movement of a partitioned mesh processing method coupled with the intermediate ballistic model and the six degree-of-freedom model(6-DOF). We compared the flow field characteristics at the velocity of 1 730.4,978.3,and 323.4 m/s. The results indicate that the pressure of the hypersonic initial flow field is much higher than that of the subsonic and supersonic initial flow fields. In the case of the subsonic(323.4 m / s)flow field,the tiny disturbance spreads throughout the whole domain. But in the cases of the supersonic (978.3 m / s) and the hypersonic (1 730.4 m / s) flow fields,it cannot spread to the upstream disturbance source,and the disturbance domain of the supersonic flow field is wider than that of the hypersonic. It is noted that the subsonic flow field has a rounded shock wave before the projectile. However,in the supersonic and hypersonic flow fields,a shear layer is formed which begins from the head of the projectile and extends outward from the side of the projectile. Then a multi-layer shock wave is formed composed of coronal shock waves,bottom shock waves,reflected shock waves,and Mach disk. 展开更多
关键词 MUZZLE flow field DIFFERENT VELOCITIES dynamic MESH TWO-DIMENSIONAL AXISYMMETRIC
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Simultaneous effects of mesh refinement, grid configuration and wall boundary condition on prediction of pressure gradients and velocity profiles of microparticles in a conical fluidized bed
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作者 Alireza Bahramian 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期123-136,共14页
The reliability and accuracy of numerical results of microparticle fluidization in a conical bed, affected simultaneously by mesh refinement, the grid configuration and the wall boundary condition (BC), are analyzed. ... The reliability and accuracy of numerical results of microparticle fluidization in a conical bed, affected simultaneously by mesh refinement, the grid configuration and the wall boundary condition (BC), are analyzed. Specifically, pressure gradients and velocity profiles of titania powder are studied for a conical bed. The Gidaspow drag correlation and different wall BCs are considered using a Eulerian-Eulerian two-fluid model. Predictions of the pressure fluctuation, power spectra of the corresponding pressure fluctuations, bed pressure drop, minimum fluidizati on veloc ity, axial solid velocity, bed expansi on ratio, and particle size distribution are compared with experimental data. Mesh sensitivity analysis using hexahedral and tetrahedral cells with a un iform mesh and n ear-wall mesh refineme nr is con ducted to inv estigate the effects of mesh configurations in estimating particle flow patterns. Simulations show that significant savings in terms of computational time are realized by choosing a uniform mesh while the hexahedral structure, the near-wall mesh refinement, and the free-slip BC give the closest fit to the experimental data. 展开更多
关键词 Conical fluidized bed Mesh CONFIGURATION GRID REFINEMENT Velocity field Pressure gradie nt
聚乙交酯丙交酯组织增强织物的设计与开发 预览
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作者 潘高峰 朱志远 +5 位作者 高建丰 姚杰雄 曾静雯 郑少东 雷励 范德彬 《纺织科技进展》 CAS 2019年第8期31-33,共3页
采用可吸收PLGA910聚合物,通过纺丝、针织制备可用于体内实质器官创面辅助止血、防漏保护以及缝合增强的医用可吸收组织增强织物。设计开发了3种针织织物,具有柔软、弹性、多孔等特点,可以满足临床实质脏器创面保护及组织增强的需求。
关键词 聚乙交酯丙交酯共聚物 缝合增强 创面保护 可吸收 针织 补片
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基于蓝牙mesh的安全保护机制的研究 预览
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作者 周莹 曾丽萍 +1 位作者 曹美媛 谷红霞 《电子世界》 2019年第15期28-28,32,共2页
本文主要对蓝牙mesh通信过程中使用的安全机制进行研究,确保在蓝牙通信网的建立、新节点的加入到节点之间数据传输过程中的安全性。在蓝牙mesh通信协议栈中,采用多级的安全防护,主要有安全分级考量、区域隔离、秘钥刷新等多种安全防护机... 本文主要对蓝牙mesh通信过程中使用的安全机制进行研究,确保在蓝牙通信网的建立、新节点的加入到节点之间数据传输过程中的安全性。在蓝牙mesh通信协议栈中,采用多级的安全防护,主要有安全分级考量、区域隔离、秘钥刷新等多种安全防护机制,从设备接入到消息传输过程中可能产生的网络风险进行考量,提高蓝牙mesh通信的安全性。 展开更多
关键词 蓝牙 通信网 安全防护 网络风险 MESH 通信协议栈 安全机制 消息传输
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我国青少年腹股沟疝发病特点及诊治值得注意的问题
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作者 唐健雄 胡星辰 《中国实用外科杂志》 CSCD 北大核心 2019年第8期788-791,共4页
对于青少年的准确界定,国际上没有权威机构给出具体的年龄范围。一般认为,年龄在13~19岁。目前国内外极少有针对青少年腹股沟疝患病率的调查。青少年处于旺盛的生长发育过程中,其腹股沟疝诊治具有特殊性,治疗仍存在很大争议。针对青少... 对于青少年的准确界定,国际上没有权威机构给出具体的年龄范围。一般认为,年龄在13~19岁。目前国内外极少有针对青少年腹股沟疝患病率的调查。青少年处于旺盛的生长发育过程中,其腹股沟疝诊治具有特殊性,治疗仍存在很大争议。针对青少年这一特殊群体的腹股沟疝病人,应该根据其具体特点,制定相应的治疗方案。术前做好详尽评估,了解有无合并特殊情况(如睾丸鞘膜积液和隐睾)。根据术前评估合理选择手术方式和修补材料,术中注意精细操作,最大限度地保护好精索血管和输精管等,避免发生并发症。视腹股沟管后壁缺损程度,考虑组织修补或使用补片给予加强。 展开更多
关键词 青少年 腹股沟疝 开放手术 腹腔镜 疝修补术 补片
基于C#和AutoCAD平面有限元网格自动生成程序开发 预览
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作者 黄向东 《信息与电脑》 2019年第13期74-76,共3页
有限单元法广泛应用于土木建筑、岩土工程、地铁隧道和水利工程等各个领域。基于此,介绍了平面有限单元网格自动生成原理,指出该原理存在两个缺陷,并提出改进方法。此外,阐述了如何在AutoCAD环境利用C#开发平面有限单元自动生成程序,描... 有限单元法广泛应用于土木建筑、岩土工程、地铁隧道和水利工程等各个领域。基于此,介绍了平面有限单元网格自动生成原理,指出该原理存在两个缺陷,并提出改进方法。此外,阐述了如何在AutoCAD环境利用C#开发平面有限单元自动生成程序,描述了程序实现的关键步骤和使用方法,同时,应用一个实例验证程序的正确性,并提供程序的应用效果。 展开更多
关键词 平面有限元 网格 自动生成
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ANPING COUNTY HUA GUANG WIRE MESH PRODUCTION CO.,LTD. 预览
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《中国经贸》 2019年第6期78-80,共3页
ANPING COUNTY HUA GUANG WIRE MESH PRODUCTION CO.,LTD is an IS09001:20CX)certified manufacture,evey month can delivery 50 containers construction material products,It has six production branches engaged in wire mesh fe... ANPING COUNTY HUA GUANG WIRE MESH PRODUCTION CO.,LTD is an IS09001:20CX)certified manufacture,evey month can delivery 50 containers construction material products,It has six production branches engaged in wire mesh fences,wire mesh partitions and gratings as well as various mesh panels We are committed to being the most reliable and efficient overseas partner for wire mesh fences distnbutors and users.Major products we offer include series wire mesh fence for expressway,railway,welded wire mesh,Europe fence,framed welded wire mesh,garden fences and various special wire mesh panels,various inetai decorative fences for city streets and sports field. 展开更多
关键词 MESH WELDED RAILWAY
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基于瓦楞辊齿廓啮合理论的运动学方程 预览
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作者 陈水胜 孔加超 +1 位作者 陈梦婷 周世棠 《包装工程》 CAS 北大核心 2019年第7期168-173,共6页
目的为了优化瓦楞辊的齿形结构,研究瓦楞辊各齿廓啮合点的运动学方程,并对其啮合非线性方程组求解,得到运动学分析图谱。方法利用微分几何和相对运动学原理建立齿廓函数,采用加权拟牛顿法,并编制相应计算程序,对各齿廓啮合点运动学方程... 目的为了优化瓦楞辊的齿形结构,研究瓦楞辊各齿廓啮合点的运动学方程,并对其啮合非线性方程组求解,得到运动学分析图谱。方法利用微分几何和相对运动学原理建立齿廓函数,采用加权拟牛顿法,并编制相应计算程序,对各齿廓啮合点运动学方程进行求解。结果通过计算实例,将U,V和UV型瓦楞辊各类楞型的原始参数代入啮合方程计算,得到一一对应的运动学性能分析图谱。该图谱显示瓦楞纸板成型时,瓦楞辊齿廓啮合引起的中心距变化规律一致,仅是对称于不同的分度角坐标轴,满足传动比i=φ2/φ1=-1,且满足齿形侧楞平行条件,φ2-φ1=180°,即两切线平行时为啮合的交替点。结论该图谱揭示了楞型尺度参数与瓦楞辊工作时转角速度、中心距变化加速度和位移的关系,并能评价各类楞型运动性能的优劣,给瓦楞辊的设计制造与误差分析提供了依据,特别是为其运动学、动力学和加工原理分析奠定了理论基础。 展开更多
关键词 瓦楞辊 啮合 加权拟牛顿法 运动学方程 楞型 图谱 尺度参数
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Characteristics of a radio-frequency cold atmospheric plasma jet produced with a hybrid cross-linear-field electrode configuration
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作者 Muhammad Ajmal KHAN 李静 +1 位作者 李和平 Hafiz Imran Ahmad QAZI 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第5期102-112,共11页
Cold atmospheric plasma(CAP)jet has wide applications in various fields including advanced materials synthesis and modifications,biomedicine,environmental protection and energy saving,etc.Appropriate control on the vo... Cold atmospheric plasma(CAP)jet has wide applications in various fields including advanced materials synthesis and modifications,biomedicine,environmental protection and energy saving,etc.Appropriate control on the volume,temperature and chemically reactive species concentratio ns of the CAP jet is of great importance in actual applications.In this paper,an radio-frequency atmospheric-pressure glow discharge(RF-APGD)plasma generator with a hybrid cross-linear-field electrode configuration is proposed.The experimental results show that,with the aid of the copper mesh located at the downstream of the traditional co-axial-type plasma generator with a cross-field electrode configuration,a linear field between the inner powered electrode of the traditional plasma generator and the copper mesh can be established.This linerfield can,to some extent,enhance the discharges at the upstream of the copper mesh,resulting in small increments(all less than 12.5%)of the species emission intensities,electron excitation temperatures and gas temperatures by keeping other parameters being unchanged.And due to the intrinsic transparent and conducting features of the grounded copper mesh to the gas flowing,electric current and heat flux of the plasma plumes,a plasma region with higher concentrations of chemically reactive species and larger plasma plume diameters is obtained at the downstream of the grounded copper mesh on the same level of the gas temperature and electron excitation temperature compared to those of the plasma free jet.In addition,the charged particle number densities at the same downstream axial location of the grounded copper mesh decrease significantly compared to those of the plasma free jet.This means that the copper mesh is also,to some extent,helpful for separating the chemically reactive neutral species from the charged particles in side a plasma environment.The preceding results indicate that the cross-linear-field electrode configuration of the plasma generator is an effective approach for tuning the characte 展开更多
关键词 COLD ATMOSPHERIC PLASMA hybrid-cross-linear-field electrode configuration grounded copper mesh PLASMA jet CHARACTERISTICS modulation
智能家庭组网设备的应用和发展趋势
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作者 苟书智 卓安生 +1 位作者 王芳 曹小波 《信息通信技术与政策》 2019年第4期69-74,共6页
运营商将智能家庭组网作为宽带业务的重要延伸来发展,以实现家庭的智能组网和Wi-Fi的全景覆盖。本文介绍了现阶段市场上的几种主流组网技术及其未来发展趋势。
关键词 智能家庭 组网技术 PLC MESH
Saint-Venant and Navier-Stokes Models for Tsunami Simulations 预览
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作者 Camille Journeau Kevin Pons Richard Marcer 《船舶与海洋工程:英文版》 2019年第1期42-63,共22页
Into the frame of the French TANDEM project (Tsunamis in the Atlantic and the English ChaNnel: Definition of the Effects through numerical Modelling) Principia has been working on the development and qualification of ... Into the frame of the French TANDEM project (Tsunamis in the Atlantic and the English ChaNnel: Definition of the Effects through numerical Modelling) Principia has been working on the development and qualification of two in-house CFD software: the 2D EOLE-SV (Saint-Venant) model for simulation of large scale tsunami propagation from the source up to coastal scale and the 3D EOLE-NS (Navier-Stokes) model dedicated to tsunami coastal impact modelling. This paper presents a large range of test cases carried out into the frame of the project and dedicated to the validation of numerical codes in various tsunami wave conditions. The main aspects of phenomena such as wave generation, propagation and coastal impact are investigated on academic situations. A real case simulation is concerned as well, the devastating 2011 Tohoku event which is compared with in-situ data. 展开更多
关键词 TSUNAMI CFD Saint-Venant (SV) MODEL Adaptive Mesh REFINEMENT (AMR) large scale propagation 3D NAVIER-STOKES (NS) MODEL COASTAL impact
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腹股沟疝修补术后补片感染的个体化手术治疗
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作者 杨慧琪 刘亦婷 +4 位作者 陈杰 申英末 刘雨辰 赵学飞 熊尧 《中华普通外科杂志》 CSCD 北大核心 2019年第9期795-797,共3页
目的总结疝修补术后补片感染的个体化手术治疗经验。方法回顾性分析北京朝阳医院疝与腹壁外科2007年1月至2018年6月期间收治的392例腹股沟疝修补术后补片感染患者的临床资料。对于开刀腹股沟疝修补术后补片感染的患者,采用原切口取出补... 目的总结疝修补术后补片感染的个体化手术治疗经验。方法回顾性分析北京朝阳医院疝与腹壁外科2007年1月至2018年6月期间收治的392例腹股沟疝修补术后补片感染患者的临床资料。对于开刀腹股沟疝修补术后补片感染的患者,采用原切口取出补片并清除感染组织;对于腹腔镜腹股沟疝修补术后感染的患者,仍釆用腹腔镜的方法取出补片。对补片感染时间、细菌类型及疝复发等指标进行分析。结果369例为开刀腹股沟疝修补术后补片感染,23例为腹腔镜腹股沟疝修补术后补片感染。发现补片感染的时间3个月以内61例,术后3个月至1年258例,术后1年以后73例。二次术后随访6~36个月,随访期间29例发生复发疝,分别在取出补片后24-34个月。感染灶细菌培养193例阳性,其中金黄色葡萄球菌126例,大肠埃希菌18例,绿脓杆菌15例。结论根据患者补片感染的具体情况制定个体化的治疗方案是安全有效的。 展开更多
关键词 腹股沟 疝修补术 补片感染
心电监测服与人体有限元分析模型的建立 预览
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作者 孙新建 邓咏梅 《纺织高校基础科学学报》 CAS 2019年第3期276-281,共6页
为仿真与分析心电监测服与人体模型在模拟穿着状态下压力分布,采用手持式三维扫描仪对穿着监测服的人体模型扫描,得到完整的点云数据。利用逆向工程软件Geomagicstudio对点云数据进行预处理和模型重建,得到相应的曲面模型。通过有限元软... 为仿真与分析心电监测服与人体模型在模拟穿着状态下压力分布,采用手持式三维扫描仪对穿着监测服的人体模型扫描,得到完整的点云数据。利用逆向工程软件Geomagicstudio对点云数据进行预处理和模型重建,得到相应的曲面模型。通过有限元软件abaqus对得到的监测服和人体曲面模型进行网格划分,生成高质量的网格模型。由监测服和人体模型曲面的偏差分析结果可知,模型曲面光滑程度符合建模精度要求;模型的网格划分没有缺失,证明建立的心电监测服与人体有限元分析模型有效。 展开更多
关键词 心电监测服 服装数字化 逆向工程 Geomagicstudio 网格划分
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Microstructure and mechanical properties of Ti-6Al-4V-5% hydroxyapatite composite fabricated using electron beam powder bed fusion
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作者 Cesar A. Terrazas Lawrenee E. Murr +3 位作者 Diego Bermudez Edel Arrieta David A. Roberson Ryan B. Wicker 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第2期309-321,共13页
A novel, Ti-6A1-4V (Ti64)/Hydroxyapatite (HA at 5% by weight concentration) metal/ceramic composite has been fabricated using electron beam powder bed fusion (EPBF) additive manufacturing (AM): specifically, the comme... A novel, Ti-6A1-4V (Ti64)/Hydroxyapatite (HA at 5% by weight concentration) metal/ceramic composite has been fabricated using electron beam powder bed fusion (EPBF) additive manufacturing (AM): specifically, the commercial electron beam melting (EBMR) process. In addition to solid Ti64 and Ti64/5% HA samples, four different unit cell (model) open-cellular mesh structures for the Ti64/5% HA composite were fabricated having densities ranging from 0.68 to 1.12g/cm^3, and corresponding Young's moduli ranging from 2.9 to 8.0 GPa, and compressive strengths ranging from -3 to 11 MPa. The solid Ti64/5%HA composite exhibited an optimal tensile strength of 123 MPa, and elongation of 5.5% in contrast to a maximum compressive strength of 875 MPa. Both the solid composite and mesh samples deformed primarily by brittle deformation, with the mesh samples exhibiting erratic, brittle crushing. Solid, EPBF-fabricated Ti64 samples had a Vickers microindentation hardness of 4.1 GPa while the Ti64/5%HA solid composite exhibited a Vickers microindentation hardness of 6.8 GPa. The lowest density Ti64/5%HA composite mesh strut sections had a Vickers microindentation hardness of 7.1 GPa. Optical metallography (OM) and seanning electron microscopy (SEM) analysis showed the HA dispersoids to be highly segregated along domain or grain boundaries, but homogeneously distributed along alpha (hcp) platelet boundaries within these domains in the Ti64 matrix for both the solid and mesh composites. The alpha platelet width varied from -5μm in the EPBF-fabricated Ti64 to -1.1μm for the Ti64/5%HA mesh strut. The precursor HA powder diameter averaged 5μm, in contrast to the dispersed HA particle diameters in the Ti64/5%HA composite which averaged 0.5μm. This work highlights the use of EPBF AM as a novel process for fabrication of a true composite structure, consisting of a Ti64 matrix and interspersed and exposed HA domains, which to the authors knowledge has not been reported before. The results also illustrate the prospects not only for fabrica 展开更多
关键词 HYDROXYAPATITE (HA) Metal-matrix ceramic composites Open-cellular (mesh) structures ELECTRON-BEAM powder bed FUSION (EPBF) Additive manufacturing (AM) Mechanical properties Microstructure characterization
AN UNFITTED hp-INTERFACE PENALTY FINITE ELEMENT METHOD FOR ELLIPTIC INTERFACE PROBLEMS
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作者 Haijun Wu Yuanming Xiao 《计算数学:英文版》 SCIE CSCD 2019年第3期316-339,共24页
An hp version of interface penalty finite element method(hp-IPFEM)is proposed to solve the elliptic interface problems in two and three dimensions on unfitted meshes.Error estimates in broken H1 norm,which are optimal... An hp version of interface penalty finite element method(hp-IPFEM)is proposed to solve the elliptic interface problems in two and three dimensions on unfitted meshes.Error estimates in broken H1 norm,which are optimal with respect to h and suboptimal with respect to p by half an order of p,are derived.Both symmetric and non-symmetric IPFEM are considered.Error estimates in L^2 norm are proved by the duality argument.All the estimates are independent of the location of the interface relative to the meshes.Numerical examples are provided to illustrate the performance of the method.This paper is adapted from the work originally post on arXiv.com by the same authors(arXiv:1007.2893v1). 展开更多
关键词 ELLIPTIC INTERFACE PROBLEMS Unfitted MESH hp-IPFEM
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