Anisotropic creep behavior of soft-hard interbedded rock masses based on 3D printing and digital imaging correlation technology

Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent properties of natural layered rock masses.In this paper,soft-hard interbedded rock masses with different dip angles were prepared based on 3D printing(3DP)sand core technology.Uniaxial compression creep tests were conducted to investigate its anisotropic creep behavior based on digital imaging correlation(DIC)technology.The results show that the anisotropic creep behavior of the 3DP soft-hard interbedded rock mass is mainly affected by the dip angles of the weak interlayer when the stress is at low levels.As the stress level increases,the effect of creep stress on its creep anisotropy increases significantly,and the dip angle is no longer the main factor.The minimum value of the long-term strength and creep failure strength always appears in the weak interlayer within 30°–60°,which explains why the failure of the layered rock mass is controlled by the weak interlayer and generally emerges at 45°.The tests results are verified by comparing with theoretical and other published studies.The feasibility of the 3DP soft-hard interbedded rock mass provides broad prospects and application values for 3DP technology in future experimental research.

Effect of TiO_(2)Addition on Properties of Al_(2)O_(3)Ceramics Prepared by Digital Light Printing(DL.P)

Ceramic slurry of 78 mass%solid loading was prepared using photosensitive acrylic resin and dispersant SP-710 as the liquid phase,Al_(2)O_(3) powder(d50=2.38μm)and TiO_(2) powder additive as the solid phase.Alumina ceramics were prepared by DLP,sintering for 4 h at 1450,1500,1550 or 1600℃,respectively.The effects of the TiO_(2) addition(0,1%,2%,3%and 5%,by mass)on the properties of the ceramics were studied.The results show that the addition of TiO_(2) can improve the sintering of Al_(2)O_(3) ceramics,significantly improve the densification,and reduce the sintering temperature.With the optimum TiO_(2) addition of 3%and the optimum sintering temperature of 1600℃,the obtained Al_(2)O_(3) ceramics have shrinkage of 15.7%,15.8%and 23.8%at the x axis,the y axis,and the z axis,respectively,the porosity of 2.4%,the bulk density of 3.74 g·cm-3 and the three-point bending strength of 251.1 MPa.Compared with the undoped alumina ceramics,the doped alumina ceramic has increased bulk density by 0.56 g·cm-3,decreased apparent porosity from 20.2%to 2.4%,and the three-point bending strength increases by 2.5 times.Therefore,the density and the strength of DLP prepared ceramics can be improved effectively by adding an appropriate amount of TiO_(2),and the performance of the DLP prepared ceramics is close to that of the pressed samples.Thus,it is hopeful to apply DLP in refractories field.

A combination of digital design and three-dimensional printing to assist treatment of thoracolumbar compression fractures using percutaneous kyphoplasty

Objective:To evaluate the clinical efficacy of the preoperative digita1 design combined with three dimensional(3D)printing models to assist percutaneous kyphoplasty(PKP)treatment for thoracolumbar compression frac tures.Methods:From January 2018 to August 2020,we obtained data of 99 patients diagnosed thoracolumbar compression fractures.These patients were divided into control group(n=50)underwent traditional PKP surgery,and observation group(n=49)underwent preoperative digital design combined with 3D printing model assisted PKP treatment.The clinical efficacy was evaluated with five parameters,including operation time,number of intraoperative radiographs,visual analogue scale(VAS)score,Cobb Angle change,and high compression rate of injured vertebrae.Results:There were statistically significant differences of operation time and number of intraoperative radio graphs between the two groups(P<0.05).For VAS score,Cobb Angle change and vertebral height compression rate,all of these three parameters were significantly improved when the patients accepted surgery teatment in two groups(P<0.05).However,there were no significant differences between control group and observation group for these three parameters either before or after surgery(P>0.05).Conclusions:Through the design of preoperative surgical guide plate and the application of 3D printing model to guide the operation,the precise design of preoperative surgical puncture site and puncture Angle of the injured vertebra was realized,the number of intraoperative radiographs was reduced,the operation time was shortened and the operation efficiency was improved.

Introduction of Digital Printing

Digital Printing is an academic journal of specializing in printing and packaging industries, found China Academy of Printing Technology. Digital Printing has been selected Core Journals of China for 2014 and 2017 edition. It mainly reports monograph of the related theory and technology, research paper of theory and application and scientific results in printing and packaging fields including basic research such as material science and engineering.

Introduction of Digital Printing

Digital Printing is an academic journal of specializing in printing and packaging industries, found China Academy of Printing Technology. Digital Printing has been selected Core Journals of China for 2014 and 2017 edition. It mainly reports monograph of the related theory and technology, research paper of theory and application and scientific results in printing and packaging fields including basic research such as material science and engineering.

Introduction of Digital Printing

Digital Printing is an academic journal of specializing in printing and packaging industries,found China Academy of Printing Technology.Digital Printing has been selected Core Journals of China for 2014 and 2017 edition.It mainly reports monograph of the related theory and technology,research paper of theory and application and scientific results in printing and packaging fields including basic research such as material science and engineering,electromechanical engineering and automation,computer science and technology,information engineering and technology,color science and technology,image communication engineering and technology,data science etc.and including other application research in the printing packing engineering such as digital media technology,printing technology,packaging technology,printing/packaging mechanical engineering,printing/packaging intelligent manufacturing,printing/packaging standards and standardization,printing packaging education and so on.It serves as a platform for promoting international and domestic academic exchanges in printing and packaging.

Digital Manufacturing： What Are We Able to Print？

在合理锻练，在现在的纸， ICT (信息和通讯技术) 的发展和添加剂生产的早期的工艺的发展怎么有潜力改变我们的协会，被外推。在下列，它在物理物质上正在分析人的进化并且这怎么塑造了我们的社会。在 human-machine-environment 关系中标记一个先验的变化的历史上的主要里程碑或关键阶段被识别了并且因而导致了我们问我们自己：什么是，我们多远，并且什么下我们能够打印？在一次尝试到识别当前的现状，加亮那些添加剂技术能提供的可能性。

The First International Digital Printing and Image Technology Exhibition & The Sixth International Exhibition of Quick Printing Equipment & Technology

Time: Sept.4-6, 2008Venue: Shenzhen Convention & Exhibition CenterSponsor: Printing and Printing Equipment Industries Association of China (PEIAC)Organizers: The Exhibition Department of

Shanghai International Digital Printing Industry Fair presents interview with EFI Reggiani

The 9th Shanghai International Digital Printing Industry Fair(TPF2018)will be held from the 19th to the 21st of April,2018,in Shanghai New International Expo Centre.TPF 2018 is organized by UBM China and SUNEXPO.As one of the most influential digital textile printing

Microfluidic bubble-generator enables digital light processing 3D printing of porous structures

Three-dimensional(3D)printing is an emerging technique that has shown promising success in engineering human tissues in recent years.Further development of vatphotopolymerization printing modalities has significantly enhanced the complexity level for 3D printing of various functional structures and components.Similarly,the development of microfluidic chip systems is an emerging research sector with promising medical applications.This work demonstrates the coupling of a digital light processing(DLP)printing procedure with a microfluidic chip system to produce size-tunable,3D-printable porosities with narrow pore size distributions within a gelatin methacryloyl(GelMA)hydrogel matrix.It is found that the generation of size-tunable gas bubbles trapped within an aqueous GelMA hydrogel-precursor can be controlled with high precision.Furthermore,the porosities are printed in two-dimensional(2D)as well as in 3D using the DLP printer.In addition,the cytocompatibility of the printed porous scaffolds is investigated using fibroblasts,where high cell viabilities as well as cell proliferation,spreading,and migration are confirmed.It is anticipated that the strategy is widely applicable in a range of application areas such as tissue engineering and regenerative medicine,among others.

水拓纹样在360°数码印花袜品中的创新应用

传承与发展传统水拓艺术,以水拓纹样为研究对象,探析其文化内涵与艺术特色在袜品设计中的实际应用,为针织袜品的创新设计提供思路。通过结合具体的袜品设计实践案例,从形状扭曲、色彩重置、语义解构、图案混搭、肌理异变5个方面,分析水拓纹样在360°数码印花袜品中的创新应用路径。研究表明,将水拓纹样与袜品设计相结合,既展现了传统水拓纹样的艺术特征与文化魅力,又满足了消费者的个性追求与人文需求,对传统艺术融入袜品设计有一定的理论指导意义与实践价值。

Effect of layer thickness on the flexural property and microstructure of 3D-printed rhomboid polymer-reinforced cemented tailing composites

For mines with poor ore bodies and surrounding rocks,the general mining method does not allow the ore to be extracted from underground safely and efficiently.For these mines,the downward layered filling mining technique is undoubtedly the most suitable mining method.The downward filling mining technique may eliminate the troubles relating to poor ore deposit conditions,such as production safety,ore loss rate,and depletion rate.However,in this technique,the safety of the artificial roof of the next stratum is of paramount importance.Cementitious tailings backfilling(CTB)that is not sufficiently cemented and causes collapses could threaten ore production.This paper explores a diamond-shaped composite structure to mimic the stability of a glued false roof in an actual infill mine based on the recently emerged three-dimensional(3D)printing technology.Experimental means such as three-point bending and digital image correlation(DIC)techniques were used to explore the flexural characteristics of 3D construction specimens and CTB combinations with different cement/tailings weight ratios at diverse layer heights.The results show that the 3D structure with a 14-mm ply height and CTB has strong flexural characteristics,with a maximum deflection value of 30.1 mm,while the 3D-printed rhomboid polymer(3D-PRP)structure with a 26-mm ply height is slightly worse in terms of flexural strength characteristics,but it has a higher maximum flexural strength of 2.83 MPa.A combination of 3D structure and CTB has more unique mechanical properties than CTB itself.This research work offers practical knowledge on the artificial roof performance of the downward layered filling mining technique and builds a scientific knowledge base regarding the successful application of CTB material in mines.

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.

Development and prospects of digital orthopedics in Hubei province

Based on the development and application of new technology,as a new interdisciplinary subject,digital orthopedics becomes an important development direction of modern medicine in the past years.Using digital orthopedics technology,such as 3D digital printing technology,mixed reality technology,provides new impetus of orthopedic surgery and indicates its great potential of precision medicine and personalized therapy for orthopedic disorders.In 2017,Hubei Branch of China Digital Orthopaedic Society of SociétéInternationale de Chirurgie Orthopédique et de Traumatologie(SICOT)was founded.It is an important milestone and academic event for the development of digital orthopedics in Hubei.After that,Hubei's digital orthopedics professionals have made great progress in clinical,scientific research,conference and social activities.The development of 5G technologies in China will provide more opportunities and challenges for global digital orthopedics in the near future.

Soft pneumatic actuators by digital light processing combined with injection-assisted post-curing

The soft robotics display huge advantages over their rigid counterparts when interacting with living organisms and fragile objects.As one of the most efficient actuators toward soft robotics,the soft pneumatic actuator(SPA)can produce large,complex responses with utilizing pressure as the only input source.In this work,a new approach that combines digital light processing(DLP)and injection-assisted post-curing is proposed to create SPAs that can realize different functionalities.To enable this,we develop a new class of photo-cross linked elastomers with tunable mechanical properties,good stretchability,and rapid curing speed.By carefully designing the geometry of the cavities embedded in the actuators,the resulting actuators can realize contracting,expanding,flapping,and twisting motions.In addition,we successfully fabricate a soft self-sensing bending actuator by injecting conductive liquids into the three-dimensional(3D)printed actuator,demonstrating that the present method has the potential to be used to manufacture intelligent soft robotic systems.

Application of digital technology in nasal reconstruction

Nasal defects are facial defects caused by trauma,tumors,or congenital diseases that seriously damage a patient’s physical and mental health.Nasal defects,from skin defects to total nasal defects,require surgical repair and reconstruction to restore the appearance and function of the nose,which have always been challenges for rhinoplasty.The development of digital technology has increased the possibility of nasal reconstruction.Digital technology is involved in the preoperative,intraoperative,and postoperative stages of nasal construction and is of great significance in improving the effect of this surgery.This article reviews the application of major digital technologies,including three-dimensional(3D)imaging technology,computer-assisted surgical navigation,and 3D printing,in nasal reconstruction and discusses the shortcomings of the current application of digital technology.

Direct Digital Manufacturing Industry Ascendant

The paper introduces the origin of the word of Direct Digital Manufacturing and other forms of address, and the working principles of Direct Digital Manufacturing technology and major types of the technology, hard- ware and software development, use of materials, applications, market growth and its development prospects. Focused presentations of Direct Digital Manufacturing （additive manufacturing） compared to traditional mechani- cal manufacturing industry in the use of prices, processing speed, reliability and cost advantages and characteris- tics. Particularly the significant challenges and competitiveness of Direct Digital Manufacturing technology in the processing of any complexity created directly the number of objects, internal structure and channel function, as well as the shape of the chassis components and structure of the matching and optimization.

非遗视角下苗族蜡染技艺的数字化传承

蜡染技艺作为中国非物质文化遗产的重要组成部分,正面临着传承困境和现代化转型的挑战。文章聚焦于探索数字化时代背景下非遗苗族蜡染技艺的创新传承方法,分析了非遗蜡染技艺传承中存在的闭塞性、局限性和单一性问题,提出建立多元化技艺体验中心、开发数字化技艺传承渠道、完善全面化技艺反馈机制等举措,助力非遗苗族蜡染实现现代化转型。

创新型数字印刷实验教学体系的研究和构建

创新型实验是指以项目式探究性实验载体,保障研究性学习,促使学生在掌握实验原理的基础上进行独立的创造性思维活动,进而开展的实验探索。文章基于湖南工业大学数字印刷实验中的创新项目及相关实验活动的开展进行分析,构建基于创新思维的新型实验教学体系,在现有实验条件的前提下开展创意创新设计实践活动,并通过数字印刷设备进行数字印刷实践,实现从设计到成品的全过程创新实验。

“跃然纸上”数字融合传播平台设计与实现

AI技术作为新兴技术之一,在简化工作流程、提高工作效率方面展现出很大作用。文章介绍了AI技术基本理论,及其在数字印刷中的应用实践分析,希望为相关领域提供参考。