Simulation on deposition and solidification processes of 7075 Al alloy droplets in 3D printing technology

In order to study the successive deposition and solidification processes of uniform alloy droplets during the drop-on-demand three dimensional（3D） printing method,based on the volume of fluid（VOF） method,a 3D numerical model was employed.In this model,the 7075 alloy with larger temperature range for phase change was used.The simulation results show that the successive deposition and solidification processes of uniform 7075 alloy droplets can be well characterized by this model.Simulated droplets shapes agree well with SEM images under the same condition.The effects of deposition and solidification of droplets result in vertical and L-shaped ridges on the surface of droplets,and tips of dendrites appear near the overlap of droplets due to rapid solidification.

Design and Application of Modern Interior Design Style System Based on Unity3D

With the constant change of fashion trends,interior design styles are changing day by day.Based on Unity3D technology,this paper develops a system for modern interior-style design and application.Taking the residential interior as a case study,the interior style design is achieved through 3D modeling and texture rendering and then combined with the Unity3D engine to achieve scene roaming and interactive design.The system enables designers to express design concepts more intuitively and efficiently and also improves customer participation and satisfaction.Through the experience of designers and customers,the system is verified to have more practical value than traditional interior design solutions.

Experimental investigation on the invert stability of operating railway tunnels with different drainage systems using 3D printing technology

In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor to ensure the invert stability by regulating the external water pressure(EWP). By means of a threedimensional(3D) printing model, this paper experimentally investigates the deformation behavior of the invert for the tunnels with the traditional drainage system(TDS) widely used in China and its optimized drainage system(ODS) with bottom drainage function. Six test groups with a total of 110 test conditions were designed to consider the design factors and environmental factors in engineering practice,including layout of the drainage system, blockage of the drainage system and groundwater level fluctuation. It was found that there are significant differences in the water discharge, EWP and invert stability for the tunnels with the two drainage systems. Even with a dense arrangement of the external blind tubes, TDS was still difficult to eliminate the excessive EWP below the invert, which is the main cause for the invert instability. Blockage of drainage system further increased the invert uplift and aggravated the track irregularity, especially when the blockage degree is more than 50%. However, ODS can prevent these invert anomalies by reasonably controlling the EWP at tunnel bottom. Even when the groundwater level reached 60 m and the blind tubes were fully blocked, the invert stability can still be maintained and the railway track experienced a settlement of only 1.8 mm. Meanwhile, the on-site monitoring under several rainstorms further showed that the average EWP of the invert was controlled within 84 k Pa, while the maximum settlement of the track slab was only 0.92 mm, which also was in good agreement with the results of model test.

3D Printing Technology for Buildings＇ Accessibility： The Tactile Map for MTE Museum in Pavia

3D printing technology is an innovative manufacturing technology used in several disciplines, whose number and diversity are growing day by day. The development of devices to improve the accessibility of buildings and urban spaces for people with disabilities through 3D priming technology is still not broadly explored. The present study is focused on filling this gap, with the realization of a tactile map of the MTE （Museum of Electrical Technology） of the University of Pavia （Italy） for blind and visually impaired people. The tactile map represents the building plan with all the information to guide the visit. The device is the result of a research process which is made by several steps and experimental tests, aimed at setting the best 3D priming profiles to meet all the requirements of the end-users. This paper describes methods and strategies applied to reach these goals： it underlines the social and technical approaches, the experimental phases and its possible future developments.

Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network.Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions.To achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the trainedmodels.The selectedmodel demonstrates exceptional segmentation performance for complex 3D facial wounds.Furthermore,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study.Our method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous method.From this result,we use 3D printing technology to illustrate the shape of the wound filling.The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design.By automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient outcomes.Additionally,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants.Our source code is available at https://github.com/SIMOGroup/WoundFilling3D.

Application of Digital Technology in Road and Bridge Design

With the development and progress of science and technology,road and bridge design has experienced rapid development,from the initial manual drawing design to the popularity of Computer-Aided Design(CAD),and then to today’s digital software design era.Early designers relied on hand-drawn paper design forms which was time-consuming and error-prone.Digital support for road and bridge design not only saves the design time but the design quality has also achieved a qualitative leap.This paper engages in the application of digital technology in road and bridge design,to provide technical reference for China’s road and bridge engineering design units,to promote the popularity of Civil3D and other advanced design software in the field of engineering design and development,ultimately contributing to the sustainable development of China’s road and bridge engineering.

3D打印在电网设备结构设计与制造中的应用概述

介绍了电网设备设计的结构快速原型、拓扑优化和逆向建模等设计输出的特点和制造需求,阐述了3D打印在电网设备制造中的工艺可行性和经济可行性,指出了现有打印技术存在打印精度与电气性能、打印价格及速度与规模化制造之间的问题,提出了适用于电网设备结构设计制造的打印尺度两极化、高性能打印材料、打印环境适应性和打印系统智能化等4点3D打印关键技术需求,明确了面向电网设备设计制造的3D打印技术发展方向。

3D打印技术在工业设计创新战略中的应用探索

3D打印技术给艺术的创新带来活力,也是科学与艺术联合创新在工业设计中的展现。本文通过3D打印技术在艺术本身信息的处理过程中,加强"人、信息、技术"三个创新基础要素的互动,对3D打印技术与艺术的行为和意识在"人、信息、技术"系统结构中进行深度认知及有效的建构,对其在工业设计领域中的发展进行探索与研究。实现3D打印技术与工业设计中的创新扣环战略,对3D打印技术与艺术的创新运用,为工业设计基础学科的帮助和提升,提供了一个有力的理论依据。

3D打印在教育领域的应用研究

3D打印机作为3D领域的一种前瞻性产品,带来了世界性的制造业革命,无需机械加工或模具,就能直接从计算机图形数据中生成任何形状的物体。目前,3D打印技术这种快速成型的新技术,已经应用于工业制造、医疗、建筑、航空航天、文化创意、数码娱乐、配件饰品行业和教育等诸多领域,越来越受到大家的关注。通过介绍3D打印的基本概念、原理以及发展状况和趋势,并通过案例设计,研究其在教育的各个学习阶段的应用;进一步分析了基于3D打印技术的教学应用模式;最后总结3D打印未来发展前景。

熔融沉积成型的3D打印专利技术综述

本文对DWPI和SIPOABS专利数据库进行检索,分析近年来涉及熔融沉积成型(FDM)3D打印技术领域的专利申请。专利申请涵盖了成型工艺和装置、熔丝材料、支撑结构和液化器结构的研究改进等方面。熔融沉积工艺具有成型速度快、成本低、成型精度高等特点,是快速成型中最具发展前景的成型工艺之一。

3D打印个体化模板在骨科手术中的应用

目的设计数字化,结合3D打印个体化导板并应用于骨科复杂手术,探讨导板及其设计对手术操作及术前规划的影响。方法选取2014年11月—2015年8月期间适合使用手术导板的25例复杂骨折患者,男21例,女14例;年龄6~67岁,平均22.7岁。骨盆骨折12例,股骨骨折5例胫腓骨骨折4例,关节周围骨折3例脊柱骨折1例结果 25例患者均顺利完成术前个体化设计和3D打印手术操作。所有手术均按术前规划进行,导板模型成功配合术中操作,结论数字化结合3D打印个体化导板能模型满足手术的个体化需求,在手术中能够准确还原术前设计;不同3D打印模型对骨科复杂手术的指导意义重大,可以降低手术的难度,减少手术时间,可以在临床工作中推广。

Accuracy of Orthodontic 3D Printed Retainers versus Thermoformed Retainers

Background: The integration of the current technology of CBCT and 3D CAD/CAM technology has great potential in the field of orthodontics, which is not yet fully investigated. The purpose of this article is to evaluate the accuracy of 3D printed retainers in comparison to vacuum formed retainers. Methods: Alginate impressions were taken for ten patients who have a CBCT scan. A 3D printed retainer and vacuum formed retainer were fabricated. Linear measure-ments were measured by two assessors using digital caliper. Every measure-ment on the 3D printed retainer was compared to the corresponding measure-ment on the thermoformed retainer. The linear measurements were Inter-canine width, Inter-premolar width (first and second premolars), Inter-molar width, Canine-midline length (both sides) and Canine-molar length (both sides). Intra-observer, and inter-observer reliability measurements were done. Results: Results showed excellent intra-observer reliability for the thermoformed retainer and the 3D printed retainer. Inter-observer measurements showed strong agreement between the measurements of the two assessors, for both retainers. The comparison of the thermoformed retainer to the 3D printed retainer showed high statistical agreement, except for the canine-molar on the right side, but with no clinical significance, p value of 0.038 and mean difference 0.19. Conclusions: The new method for fabricating a 3D printed retainer is accurate and reliable in comparison to the vacuum formed retainer (conventional method). CBCT proved to be efficient for fabrication of a custom made appliances.

Design Consideration for Additive Manufacturing: Fused Deposition Modelling

Additive Manufacturing (AM) technologies have progressed in the past few years and many of them are now capable of producing functional parts instead of mere prototypes. AM provides a multitude of benefits, especially in design freedom. However, it still lacks industrial relevance because of the absence of comprehensive design rules for AM. Although AM is usually advertised as being the solution for all traditional manufacturing design limitations, the fact is that AM only replaces these limitations with a different set of restrictions. To fully exploit the advantages of AM, it is necessary to understand these limitations and consider them early during the design process. The establishment of design considerations in AM enables parts and process optimization. This paper discusses the design considerations that will lead to optimize part quality. Specifically, the work discusses the Fused Deposition Modeling (FDM) due to its common use and availability. These considerations are drawn from literature and from experiments done by the authors. The experiments done by the authors include an investigation for the influence of elevated service temperature on the performance of FDM PLA parts, benchmarking the capability of FDM to print overhangs and bridges without supports, studying the influence of processing parameters over dimensional accuracy, and the effect of processing parameters on the final FDM samples modulus of elasticity. The work presents a case study investigating the correct clearances for FDM parts and finally a redesign for AM case study of a support bracket originally manufactured using traditional manufacturing methods taking into consideration the design considerations discussed in this paper.

Co-continuous Composite Material Design Using the Volumetric Distance Field Based on Analytic Shape Functions

An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distance field( VDF). After generating a set of VDF-based features for the given exterior shape and desired internal core structure,a series of simple modifications in distance fields enabled us to obtain an arbitrarily-shaped complex co-continuous composite material computational model. Design results and manufactured prototypes through 3 D printing technology show that the proposed methodology has the potential to open a new paradigm for producing multifunctional next generation co-continuous composite materials which are impossible to design and manufacture using traditional CAD and CAM.

Teaching Reform of Building Construction Course under the Background of New Digital Technology

With the advent of the information age,all walks of life have paid more and more attention to the development and application of digital technology.At the same time,the construction industry,which is a traditionally important industry,is not an exception.A series of high-tech digital technologies have been widely used in architectural design and construction,such as BIM technology,3D printing technology,and VR technology.In view of the teaching link of architectural talent training,it is necessary to keep up with the development trend of the digital age,integrate these three kinds of technology into architectural teaching,and impart knowledge to students from planar 2D textbooks to 3D visual digital models,and further transform it from 3D digital to physical perceive or virtual simulation level,and reform teaching methods in all dimensions and in all dimensions to improve teaching effect.In this paper,the feasibility and necessity of integration of the above three architectural digital techniques into the teaching process of"building construction"from the aspects of teaching content,teaching method and teaching evaluation were discussed,and a new teaching model under the background of digital technology was proposed,which has certain teaching reference significance.

Three-dimensional printing technology for treatment of intracranial aneurysm

Background:The development of three-dimensional (3D) printing technology provides a new method for surgical treatment,but currently there are few reports on its application in the treatment of aneurysm.The aim of the present study was to explore the materials and methods of fabricating 3D printed individual aneurysm model and its value in the treatment of intracranial aneurysm.Methods:Twenty-four patients with intracranial aneurysm diagnosed by CTA who had undergone operation in our hospital were analyzed retrospectively.CTA Data collected at the time of surgery was used for reconstruction.Soft Mimics 17.0 was used to reconstruct the thin layer CTA scan data into 3D image and the final data was sent to the 3D printer for fabricating the model.We compared the proposed 3D printed model-based preoperative plan and the actual approach used in the surgery based on CTA data to evaluate the value of the 3D printed model in preoperative planning,and picked out the materials which were more suitable for the clinic.Results:Twenty-four aneurysm models with high degree of reality were fabricated successfully with 3D-printing technology.The patients' blood vessels,skulls and aneurysms were printed into the reality model at a ratio of 1:1.It is reported that the soft material-based,3D printed vascular and aneurysm model more closely resembled the characteristics of the real blood vessels,thus provides a better simulation compared to the plaster-based model.Compared with the original operation plan,3D printed model could be used for pre-operative aneurysm clip selection,and provide more intuitive information in selection of operational approach.Conclusions:3D printed model can be used as an operational physical model to design operative schemes,choose the best operative paths and select suitable aneurysm clips by its high simulation degree and individualized characteristics.The model is helpful for surgical planning,especially for the preoperative plan of treating refractory multiple aneurysms and giant aneurysms.

Material,design,and fabrication of custom prosthetic liners for lower-extremity amputees:A review

As a physical interface,a prosthetic liner is commonly used as a transition material between the residual limb and the stiff socket.Typically made from a compliant material such as silicone,the main function of a prosthetic liner is to protect the residual limb from injuries induced by load-bearing normal and shear stresses.Compared to conventional liners,custom prosthetic lower-extremity(LE)liners have been shown to better relieve stress concentrations in painful and sensitive regions of the residual limb.Although custom LE liners have been shown to offer clinical benefits,no review article on their design and efficacy has yet been written.To address this shortcoming in the literature,this paper provides a comprehensive survey of custom LE liner materials,design,and fabrication methods.First,custom LE liner materials and components are summarized,including a description of commercial liners and their efficacy.Subsequently,digital methods used to design and fabricate custom LE liners are addressed,including residual limb biomechanical modeling,finite element-based design methods,and 3-D printing techniques.Finally,current evaluation methods of custom/commercial LE liners are presented and discussed.We hope that this review article will inspire further research and development into the design and manufacture of custom LE liners.

Exploring innovative techniques for damage control during natural disasters

The study critically examines the principles,mechanisms,and effectiveness of different damage control tech-niques in dealing with natural disasters,emphasizing their pivotal role in minimizing casualties and economic losses.Each of these damage control techniques is mapped based on their applications and relevance in the key areas of natural disaster management.By utilizing various real-world instances,the present study shows that the effective implementation of various innovative techniques is shaping the space of natural disaster management in a global context.The integration of different innovative techniques into the existing natural disaster management system has improved the survival rate,economic performance,and sustainable development.The study finds that innovative disaster financing models,clear strategies,and creating awareness among communities can improve the overall efficiency of innovative techniques that are currently used for damage control during natural disaster events.Despite the substantial advantages of these creative strategies,the study acknowledges challenges such as financial constraints,unclear policy goals,and community adaptation requirements.The study also indicates that in the future,automatic damage restoration,quick prototyping,and additive engineering will play a vital role in controlling damage from catastrophic events,while it acknowledges limitations in temporal scope,generaliz-ability,andfinancial constraints.

推动数字产品定义(MBD)技术应用过程中的标准体系建设

阐述了数字产品定义(MBD)技术的优越性、企业应用数字产品定义(MBD)技术的必要性以及数字产品定义(MBD)技术实施过程中要注意的问题,指出标准体系建设是保证数字产品定义(MBD)技术应用成功的必由之路。

GIS技术在铁路选线设计中的应用研究

随着交通行业的不断发展,城市与城市间的距离越来越短,人们花在路途上的时间越来越少。尤其是高铁等普及,已然成为重要的交通工具,铁路线路设计技术发展日益成熟,尤其是GIS技术的应用,给铁路运输产业的发展注入了新鲜的血液。GIS技术在铁路事业上的应用主要体现在三维立体数据的统一与交换,建立三维数据模型,通过地理位置元素,对空间数据模型进行数据分析,实现数据的转换和分析,为工程设计提供数据和立体模拟结构的应用平台。在铁路路线设计上应用GIS技术,不仅可以对现有数据分析和方案设计,而且对后续工程设计、数据收集与分析、立体模型展示等有着不可估量的作用。运用GIS技术,使得铁路选线作业中设计分析更加科学合理,同时相对于传统设计表现了独特的优势。