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Stability of three-dimensional printable foam concrete as function of surfactant characteristics

《结构与土木工程前沿(英文)》   页码 935-947 doi: 10.1007/s11709-023-0964-z

摘要: Extrudability is one of the most critical factors when designing three-dimensional printable foam concrete. The extrusion process likely affects the foam stability which necessitates the investigation into surfactant properties particularly for concrete mixes with high foam contents. Although many studies have been conducted on traditional foam concrete in this context, studies on three-dimensional printed foam concrete are scarce. To address this research gap, the effects of surfactant characteristics on the stability, extrudability, and buildability of three-dimensional printed foam concrete mixes with two design densities (1000 and 1300 kg/m3) using two different surfactants and stabilizers (synthetic-based sodium lauryl sulfate stabilized with carboxymethyl cellulose sodium salt, and natural-based hingot surfactant stabilized with xanthan gum) were investigated in this study. Fresh density tests were conducted before and after the extrusion to determine stability of the foam concrete. The results were then correlated with surfactant qualities, such as viscosity and surface tension, to understand the importance of key parameters in three-dimensional printing of foam concrete. Based on the experimental results, surfactant solu1tion with viscosity exceeding 5 mPa·s and surface tension lower than 31 mN/m was recommended to yield stable three-dimensional printable foam concrete mixes. Nevertheless, the volume of foam in the mix significantly affected the printability characteristics. Unlike traditional foam concrete, the variation in the stabilizer concentration and density of concrete were found to have insignificant effect on the fresh-state-characteristics (slump, slump flow, and static yield stress) and air void microstructure of the stable mixes.

关键词: foam concrete     3D printable concrete     stability     rheology     air void microstructure    

Three-dimensional reconstruction of light microscopy image sections: present and future

null

《医学前沿(英文)》 2015年 第9卷 第1期   页码 30-45 doi: 10.1007/s11684-014-0337-z

摘要:

Three-dimensional (3D) image reconstruction technologies can reveal previously hidden microstructures in human tissue. However, the lack of ideal, non-destructive cross-sectional imaging techniques is still a problem. Despite some drawbacks, histological sectioning remains one of the most powerful methods for accurate high-resolution representation of tissue structures. Computer technologies can produce 3D representations of interesting human tissue and organs that have been serial-sectioned, dyed or stained, imaged, and segmented for 3D visualization. 3D reconstruction also has great potential in the fields of tissue engineering and 3D printing. This article outlines the most common methods for 3D tissue section reconstruction. We describe the most important academic concepts in this field, and provide critical explanations and comparisons. We also note key steps in the reconstruction procedures, and highlight recent progress in the development of new reconstruction methods.

关键词: microtomy     3D imaging     computer-assisted image processing     3D printing     tissue scaffold    

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

《医学前沿(英文)》 2011年 第5卷 第3期   页码 254-270 doi: 10.1007/s11684-011-0153-7

摘要: Multislice computed tomography (CT) has been widely used in clinical practice for the diagnosis of cardiovascular disease due to its reduced invasiveness and high spatial and temporal resolution. As a reliable alternative to conventional angiography, multislice CT angiography has been recognized as the method of choice for detecting and diagnosing head and neck vascular disease, abdominal aortic aneurysm, aortic dissection, and pulmonary embolism. In patients with suspected coronary artery disease, although invasive coronary angiography still remains as the gold standard technique, multislice CT angiography demonstrates high diagnostic accuracy; in selected patients, it is considered as the first-line technique. The imaging diagnosis of cardiovascular disease is based on a combination of two-dimensional (2D) and three-dimensional (3D) visualization tools to enhance the diagnostic value. This is facilitated by reconstructed visualizations which provide additional information about the extent of the disease, an accurate assessment of the spatial relationship between normal structures and pathological changes, and pre-operative planning and post-procedure follow-up. The aim of the present article is to present an overview of the diagnostic performance of various 2D and 3D CT visualizations in cardiovascular disease, including multiplanar reformation, maximum intensity projection, volume rendering, and virtual intravascular endoscopy. The recognition of the potential value of these visualizations will assist clinicians in efficiently using the multislice CT imaging modality for the diagnostic management of patients with cardiovascular disease.

关键词: cardiovascular disease     multislice computed tomography     three-dimensional reconstruction     diagnosis     visualization    

Fabrication of Si-based three-dimensional microbatteries: A review

Chuang YUE, Jing LI, Liwei LIN

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 459-476 doi: 10.1007/s11465-017-0462-x

摘要:

High-performance, Si-based three-dimensional (3D) microbattery systems for powering micro/nano-electromechanical systems and lab-on-chip smart electronic devices have attracted increasing research attention. These systems are characterized by compatible fabrication and integratibility resulting from the silicon-based technologies used in their production. The use of support substrates, electrodes or current collectors, electrolytes, and even batteries used in 3D layouts has become increasingly important in fabricating microbatteries with high energy, high power density, and wide-ranging applications. In this review, Si-based 3D microbatteries and related fabrication technologies, especially the production of micro-lithium ion batteries, are reviewed and discussed in detail in order to provide guidance for the design and fabrication.

关键词: three-dimensional (3D)     wafer-scale     Si-based anode     micro-LIBs     thin-film deposition    

Three-dimensional composite Li metal anode by simple mechanical modification for high-energy batteries

《能源前沿(英文)》 2023年 第17卷 第5期   页码 569-584 doi: 10.1007/s11708-023-0875-7

摘要: Lithium (Li) metal is believed to be the “Holy Grail” among all anode materials for next-generation Li-based batteries due to its high theoretical specific capacity (3860 mAh/g) and lowest redox potential (−3.04 V). Disappointingly, uncontrolled dendrite formation and “hostless” deposition impede its further development. It is well accepted that the construction of three-dimensional (3D) composite Li metal anode could tackle the above problems to some extent by reducing local current density and maintaining electrode volume during cycling. However, most strategies to build 3D composite Li metal anode require either electrodeposition or melt-infusion process. In spite of their effectiveness, these procedures bring multiple complex processing steps, high temperature, and harsh experimental conditions which cannot meet the actual production demand in consideration of cost and safety. Under this condition, a novel method to construct 3D composite anode via simple mechanical modification has been recently proposed which does not involve harsh conditions, fussy procedures, or fancy equipment. In this mini review, a systematic and in-depth investigation of this mechanical deformation technique to build 3D composite Li metal anode is provided. First, by summarizing a number of recent studies, different mechanical modification approaches are classified clearly according to their specific procedures. Then, the effect of each individual mechanical modification approach and its working mechanisms is reviewed. Afterwards, the merits and limits of different approaches are compared. Finally, a general summary and perspective on construction strategies for next-generation 3D composite Li anode are presented.

关键词: lithium (Li)-ion battery (LIB)     Li metal battery     three-dimensional (3D) composite Li metal anode     mechanical modification     reducing local current density    

liquid bridge forces on rheological properties, and resulting extrudability and constructability of three-dimensional

《结构与土木工程前沿(英文)》   页码 1295-1309 doi: 10.1007/s11709-023-0999-1

摘要: Extrudability and constructability are two important, yet contradictory issues pertaining to the construction of three-dimensional (3D) printing concrete. Extrudability is easily achieved when 3D printing cement mortar has a high water content and low cohesion, but the printed structure is easily collapsible. However, a 3D printing cement mortar with a low water content and high cohesion has a relatively stable printed structure although the cement mortar might not be extrudable. This study proposes a particle-based method to simulate 3D printing mortar extrusion and construction as an overall planning tool for building design. First, a discrete element model with time-varying liquid bridge forces is developed to investigate the microscopic effects of these forces on global rheological properties. Next, a series of numerical simulations relevant to 3D printable mortar extrudability and constructability are carried out. The study demonstrates that the effects of time-varying liquid bridge forces on rheological properties and the resulting extrudability and constructability of 3D printing mortar are considerable. Furthermore, an optimized region that satisfies both the extrusion and construction requirements is provided for 3D printing industry as a reference.

关键词: particle-based simulation     liquid bridge force     rheological property     3D printing mortar     extrudability     constructability    

Non linear modeling of three-dimensional reinforced and fiber concrete structures

Fatiha IGUETOULENE, Youcef BOUAFIA, Mohand Said KACHI

《结构与土木工程前沿(英文)》 2018年 第12卷 第4期   页码 439-453 doi: 10.1007/s11709-017-0433-7

摘要: Under the effect of the ascending loading, the behavior of reinforced concrete structures is rather non linear. Research in industry and science aims to extend forward the use of non-linear calculation of fiber concrete for structural parts such as columns, veils and pious, as the fiber concrete is more ductile behavior then the classical concrete behavior. The formulation of the element has been established for modeling the nonlinear behavior of elastic structures in three dimensions, based on the displacement method. For the behavior of concrete and fiber concrete compressive and tensile strength (stress-strain) the uniaxial formulation is used. For steel bi-linear relationship is used. The approach is based on the discretization of the cross section trapezoidal tables. Forming the stiffness matrix of the section, the integral of the surface is calculated as the sum of the integrals on each of the cutting trapezoids. To integrate on the trapeze we have adopted the type of Simpson integration scheme.

关键词: numerical modeling     column and beam     nonlinear analysis     fibers     pious     reinforcement     3D formulation     response load-deflection    

Single-chip 3D electric field microsensor

Biyun LING, Yu WANG, Chunrong PENG, Bing LI, Zhaozhi CHU, Bin LI, Shanhong XIA

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 581-590 doi: 10.1007/s11465-017-0454-x

摘要:

This paper presents a single-chip 3D electric field microsensor, in which a sensing element is set at the center to detect the Z-axis component of an electrostatic field. Two pairs of sensing elements with the same structure are arranged in a cross-like configuration to measure the X- and Y-axis electrostatic field components. An in-plane rotary mechanism is used in the microsensor to detect the X-, Y-, and Z-axis electrostatic field components simultaneously. The proposed microsensor is compact and presents high integration. The microsensor is fabricated through a MetalMUMPS process. Experimental results show that in the range of 0–50 kV/m, the linearity errors of the microsensor are within 5.5%, and the total measurement errors of the three electrostatic field components are less than 14.04%.

关键词: electric field microsensor     three-dimensional     single-chip     in-plane rotation    

三维仿生支架平台的刚度和层尺寸对癌细胞分离的影响 Article

张维冠, 刘子玉, 彭慧芝

《工程(英文)》 2021年 第7卷 第10期   页码 1426-1435 doi: 10.1016/j.eng.2020.09.010

摘要: 本研究根据精确控制的设计参数(包括刚度、层数和结构布局),开发了三维(3D)仿生支架平台,用于分离鼻咽癌(NPC43)细胞与永生化鼻咽上皮(NP460)细胞。使用这些3D仿生平台进行研究发现,在较硬的双层支架平台[顶层为40/10 μm沟脊/沟槽(R/T)栅格,底层为20/10 μm R/T网格]上,NPC43细胞与NP460细胞的分离效率可达89%

关键词: 细胞分离     细胞迁移     鼻咽癌(NPC)     3D支架平台    

基于双目立体匹配和B样条的三维人脸点云孔洞修补算法 Research Articles

黄源1,2,达飞鹏1,2

《信息与电子工程前沿(英文)》 2022年 第23卷 第3期   页码 398-408 doi: 10.1631/FITEE.2000508

摘要: 在基于结构光的三维人脸点云数据采集过程中,由于环境、遮挡以及光照强度等因素影响,采集到的数据往往会出现孔洞区域,从而影响后续识别效果。本文提出一种采用立体匹配技术结合B样条的孔洞修补方法。算法首先利用光栅投影过程中获取的相位信息定位点云中的孔洞区域,同时提取边界点集。然后将立体匹配算法获取的人脸点云数据同光栅投影法采集的数据进行配准,在孔洞处选取初始修补控制点。再利用B样条曲线形状可由少数关键点大致描述这一特性,将控制点作为关键点放入孔洞区域进行曲面重建迭代计算。仿真使用光滑陶瓷杯和人脸模型进行,结果表明,该算法能够准确再现被测物体表面的细节和复杂形状。同时也说明所提方法具有强鲁棒性,能够在完全无先验信息的情况下对物体复杂区域实现孔洞修补,并且修补后的点云更加接近原始数据。该方法可广泛应用于需要精确人脸识别的领域。

关键词: 三维点云;孔洞修补;立体匹配;B样条    

欠驱动3D双足机器人步态切换控制策略 Research Articles

Hai-hui YUAN, Yi-min GE, Chun-biao GAN

《信息与电子工程前沿(英文)》 2019年 第20卷 第8期   页码 1026-1035 doi: 10.1631/FITEE.1800206

摘要: 本文针对一个五杆欠驱动3D双足机器人步态切换问题,提出一种基于分层控制的切换控制策略。该策略包括切换控制器设计以及基于事件的反馈控制器设计。最后,为验证所提控制策略的有效性,针对欠驱动3D双足机器人进行了数值仿真验证。

关键词: 步态切换;欠驱动3D双足机器人;基于事件的反馈控制器;自适应控制律    

Numerical analysis of 3-D unsteady flow in a vaneless counter-rotating turbine

ZHAO Qingjun, WANG Huishe, ZHAO Xiaolu, XU Jianzhong

《能源前沿(英文)》 2007年 第1卷 第3期   页码 352-358 doi: 10.1007/s11708-007-0053-3

摘要: To reveal the unsteady flow characteristics of a vaneless counter-rotating turbine (VCRT), a three-dimensional, viscous, unsteady computational fluid dynamics (CFD) analysis was performed. The results show that unsteady simulation is superior to steady simulation because more flow characteristics can be obtained. The unsteady effects in upstream airfoil rows are weaker than those in downstream airfoil rows in the VCRT. The static pressure distribution along the span in the pressure surface of a high pressure turbine stator is more uniform than that in the suction surface. The static pressure distributions along the span in the pressure surfaces and the suction surfaces of a high pressure turbine rotor and a low pressure turbine rotor are all uneven. The numerical results also indicate that the load of a high pressure turbine rotor will increase with the increase of the span. The deviation is very big between the direction of air flow at the outlet of a high pressure turbine rotor and the axial direction. A similar result can also be obtained in the outlet of a low pressure turbine rotor. This means that the specific work of a high pressure turbine rotor and a low pressure turbine rotor is big enough to reach the design objectives.

关键词: unsteady flow     three-dimensional     pressure distribution     similar result     unsteady simulation    

Three-dimensional numerical modeling of single geocell-reinforced sand

Xiaoming YANG, Jie HAN, Robert L. PARSONS, Dov LESHCHINSKY,

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 233-240 doi: 10.1007/s11709-010-0020-7

摘要: This paper summarizes the development of a three-dimensional numerical model for analyzing single geocell-reinforced soil. In this model, the infill soil was modeled using the Duncan-Chang model, which can simulate non-linearity and stress-dependency of soil. Geocell was modeled using linearly elastic plate elements, which can carry both bending and membrane stresses. A linear interface stress-strain relationship with a Mohr-Coulomb yield criterion was adopted to model the interface friction between the geocell wall and the soil. By modeling the geocell and the soil separately, the interaction between the soil and the geocell can be accurately simulated. To verify this model, a plate load test was conducted in the laboratory, in which a 12-cm-thick sand layer reinforced by a single geocell was subjected to a vertical load from a circular steel plate. The load-displacement curves and the horizontal tensile strain of the geocell were recorded during the test. A numerical model was created according to the setup of the load test. The numerical results compared reasonably well with the test data.

关键词: geosynthetic reinforcement     geocell     numerical model     FLAC3D    

三维体目标间拓扑方向关系描述和推理

刘新,李成名,刘文宝

《中国工程科学》 2013年 第15卷 第5期   页码 8-13

摘要: 目标对象与参照物在X、Y、Z 3个坐标轴上投影间的Allen区间关系分别为[R1]、[R2]和[R3],提出利用Allen区间关系对[(R1,R2,R3)]描述三维拓扑方向区域,用定义法研究拓扑方向关系定性推理

关键词: 空间关系     拓扑关系     方向关系     拓扑方向关系     三维空间    

水电工程地质信息三维可视化与分析

刘东海,钟登华,李明超

《中国工程科学》 2004年 第6卷 第5期   页码 65-70

摘要:

传统工程地质资料的描述和解释直观性差,往往不能充分揭示地质构造空间变化的规律,所以越来越难以满足设计人员进行空间地质分析的要求,文章利用GIS和可视化技术,提出了水电工程地质信息数字化与三维可视化方法,实现了地质信息的可视化分析,工程应用表明该方法可为直观描述复杂地质构造的空间展布及其相互关系,以及进行工程地质交互设计提供有效的途径。

关键词: 水电工程     地质信息     三维可视化     GIS     地质分析    

标题 作者 时间 类型 操作

Stability of three-dimensional printable foam concrete as function of surfactant characteristics

期刊论文

Three-dimensional reconstruction of light microscopy image sections: present and future

null

期刊论文

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

期刊论文

Fabrication of Si-based three-dimensional microbatteries: A review

Chuang YUE, Jing LI, Liwei LIN

期刊论文

Three-dimensional composite Li metal anode by simple mechanical modification for high-energy batteries

期刊论文

liquid bridge forces on rheological properties, and resulting extrudability and constructability of three-dimensional

期刊论文

Non linear modeling of three-dimensional reinforced and fiber concrete structures

Fatiha IGUETOULENE, Youcef BOUAFIA, Mohand Said KACHI

期刊论文

Single-chip 3D electric field microsensor

Biyun LING, Yu WANG, Chunrong PENG, Bing LI, Zhaozhi CHU, Bin LI, Shanhong XIA

期刊论文

三维仿生支架平台的刚度和层尺寸对癌细胞分离的影响

张维冠, 刘子玉, 彭慧芝

期刊论文

基于双目立体匹配和B样条的三维人脸点云孔洞修补算法

黄源1,2,达飞鹏1,2

期刊论文

欠驱动3D双足机器人步态切换控制策略

Hai-hui YUAN, Yi-min GE, Chun-biao GAN

期刊论文

Numerical analysis of 3-D unsteady flow in a vaneless counter-rotating turbine

ZHAO Qingjun, WANG Huishe, ZHAO Xiaolu, XU Jianzhong

期刊论文

Three-dimensional numerical modeling of single geocell-reinforced sand

Xiaoming YANG, Jie HAN, Robert L. PARSONS, Dov LESHCHINSKY,

期刊论文

三维体目标间拓扑方向关系描述和推理

刘新,李成名,刘文宝

期刊论文

水电工程地质信息三维可视化与分析

刘东海,钟登华,李明超

期刊论文