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.

Three-dimensional printing technology for patient-matched instrument in treatment of cubitus varus deformity:A case report

BACKGROUND Recently,medical three-dimensional printing technology(3DPT)has demonstrated potential benefits for the treatment of cubitus varus deformity(CVD)by improving accuracy of the osteotomy through the use of an osteotomy guide,with or without a patient-mated plate.Here,we present an interesting CVD case,involving a patient who was treated with corrective biplanar chevron osteotomy using an innovative customized osteotomy guide and a newly designed patient-matched monoblock crosslink plate created with 3DPT.CASE SUMMARY A 32-year-old female presented with a significant CVD from childhood injury.A computer simulation was processed using images from computerized tomography scans of both upper extremities.The biplanar chevron osteotomy was designed to create identical anatomy between the mirror image of the contralateral distal humerus and the osteotomized distal humerus.Next,the customized osteotomy guide and patient-matched monoblock crosslink plate were designed and printed.A simulation osteotomy was created for the real-sized bone model,and the operation was performed using the posterior paratricipital approach with k-wire positioning from the customized osteotomy guide as a predrilled hole for screw fixation to achieve immediate control of the reduction after osteotomy.Our method allowed for successful treatment of the CVD case,significantly improving the patient’s radiographic and clinical outcomes,with satisfactory result.CONCLUSION 3DPT-created patient-matched osteotomy guide and instrumentation provides accurate control during CVD correction.

Application and Analysis of Computer Virtual Simulation Technology in Three-dimensional Animation Production

With the continuous promotion of computer technology, the application system of virtual simulation technology has been further optimized and improved, and has been widely used in various fields of social development, such as urban construction, interior design, industrial simulation and tourism teaching. China's three-dimensional animation production started relatively late, but has achieved good results with the support of related advanced technology in the process of development. Computer virtual simulation technology is an important technical support in the production of three-dimensional animation. In this paper, firstly, the related content of computer virtual simulation technology was introduced. Then, the specific application of this technology in the production of three-dimensional animation was further elaborated, so as to provide some reference for the improvement of the production effect of three-dimensional animation in the future.

Application Status and Prospect of Three-Dimensional Printing Technology in the Field of Medical Devices

Three-dimensional(3D)printing technology belongs to a new manufacturing science and has been widely used in various fields of industry.This article will apply 3D printing technology as its main research topic,with emphasis on its application in the field of medical devices and prospects for contribution.

Application of Three-dimensional Laser Scanning Technology in the Teaching Practice of Surveying and Mapping of Ancient Buildings

Based on the study of the application of three-dimensional laser scanning technology in ancient building surveying and mapping,this paper briefly describes the working principle and flow of three-dimensional laser scanning technology.Based on the practical application,this paper puts forward the discussion of related problems and matters needing attention.This has a certain reference significance for the study of new technology in surveying and mapping of ancient buildings.

Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology

Objective To discuss the measurement of bone tumor volume on the basis of three dimensional images segmentation technology. Methods Twenty patients with lacunar bone tumor from Tianjin Hospital and Tongji Hospital were included in the

Grid-based computer-generated holograms synthesizing for holographic three-dimensional display

To reduce the computing time of composite computer-generated holograms （CGHs） gen- eration based upon the angular projection algorithm for holographic three-dimensional （3D） display, a grid-based holographic display （ GHD ） scheme was designed. The grid computing technology was applied to numerically process the different angular projections of an object in distributed-parallel manner to create the corresponding CGHs. The whole treatment of a projection was regarded as a job executed on the grid node machine. The number of jobs which were submitted to grid nodes, therefore, was equal to that of the projections of the object. A Condor-based grid testbed was constructed to verify the feasibility of the GHD scheme, and a graphical user interface （GUI） program and several service modules were developed for it. A 3D terrain model as an example was processed on the testbed. The result showed that the scheme was feasible and able to improve the execution elficiency greatly.

Research on CT characteristics reconstruction technology

The traditional computed tomography(CT)reconstruction methods are noisy,low resolution,poor contrast,and generally not suitable to detect the smaller flaws.Besides,the filter design is also difficult.The CT characteristics reconstruction technology was brought forward to improve in these aspects,which is defined to directly reconstruct the characteristics of the projection for the best requirements not the overall image quality.The two-dimension(2D)and three-dimension(3D)CT characteristics reconstruction algorithm were firstly introduced,then by detailed analysis,experimental results and comparsion of parameters calculated,its advantages in keeping better high-frequency feature,better noise immunity,short time-consuming and easier design are verified.

Microfluidic three-dimensional cell culture of stem cells for high-throughput analysis

Although the recent advances in stem cell engineering have gained a great deal of attention due to their high potential in clinical research,the applicability of stem cells for preclinical screening in the drug discovery process is still challenging due to difficulties in controlling the stem cell microenvironment and the limited availability of high-throughput systems.Recently,researchers have been actively developing and evaluating three-dimensional(3D)cell culture-based platforms using microfluidic technologies,such as organ-on-a-chip and organoid-on-a-chip platforms,and they have achieved promising breakthroughs in stem cell engineering.In this review,we start with a comprehensive discussion on the importance of microfluidic 3D cell culture techniques in stem cell research and their technical strategies in the field of drug discovery.In a subsequent section,we discuss microfluidic 3D cell culture techniques for high-throughput analysis for use in stem cell research.In addition,some potential and practical applications of organ-on-a-chip or organoid-on-a-chip platforms using stem cells as drug screening and disease models are highlighted.

Three-dimensional printed talar prosthesis with biological function for giant cell tumor of the talus:A case report and review of the literature

BACKGROUND Giant cell tumors(GCT)are most commonly seen in the distal femur.These tumors are uncommon in the small bones of the hand and feet,and a very few cases have been reported.A giant cell tumor of the talus is rarely seen clinically and could be a challenge to physicians.CASE SUMMARY We report a rare case of GCT of the talus in one patient who underwent a new reconstructive surgery technique using a three-dimensional(3D)printing talar prosthesis.The prosthesis shape was designed by tomographic image processing and segmentation using technology to match the intact side by mirror symmetry with 3D post-processing technologies.The patient recovered nearly full range of motion of the ankle after 6 mo.The visual analogue scale and American Orthopaedic Foot and Ankle Society scores were 1 and 89 points,respectively.CONCLUSION We demonstrated that 3D printing of a talar prosthesis is a beneficial option for GCT of the talus.

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.

Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology

Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak,cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laserscanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%e90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study.

Selective removal technology using chemical etching and excimer assistance in precision recycle of color filter

Color filters are produced using semiconductor production techniques although problems with low yield remain to be addressed. This study presents a new means of selective removal using excimer irradiation, chemical etching, or electrochemical machining on the fifth generation TFT LCDs. The selective removal of microstructure layers from the color filter surface of an optoelectronic flat panel display, as well as complete removal of the ITO thin-films, RGB layer, or resin black matrix (BM) layer from the substrate is possible. Individual defective film layers can be removed, or all films down to the Cr layer or bare glass can be completely eliminated. Experimental results demonstrate that defective ITO thin-films, RGB layers, or the resin BM layer can now be recycled with a great precision. When the ITO or RGB layer proves difficult to remove, excimer light can be used to help with removal. During this recycling process, the use of 225 nm excimer irradiation before chemical etching, or electrochemical machining, makes removal of stubborn film residues easy, effectively improving the quality of recycled color filters and reducing fabrication cost.

Latest development of display technologies

In this review we will focus on recent progress in the field of two-dimensional（2D） and three-dimensional（3D）display technologies.We present the current display materials and their applications,including organic light-emitting diodes（OLEDs）,flexible OLEDs quantum dot light emitting diodes（QLEDs）,active-matrix organic light emitting diodes（AMOLEDs）,electronic paper（E-paper）,curved displays,stereoscopic 3D displays,volumetric 3D displays,light field3 D displays,and holographic 3D displays.Conventional 2D display devices,such as liquid crystal devices（LCDs） often result in ambiguity in high-dimensional data images because of lacking true depth information.This review thus provides a detailed description of 3D display technologies.

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.

Recent progress in microbial cell surface display systems and their application on biosensors

Microbial cell surface display technology is a recombinant technology to express target proteins on the cell membrane,which can be used to redesign the cell surface with functional proteins and peptides.Bacterial and yeast surface display systems are the most common cell surface display systems of prokaryotic and eukaryotic proteins,that are widely applied as the core elements in the field of biosensors due to their advantages,including enhanced stability,high yield,good safety,expression of larger and more complex proteins.To further promote the performance of biosensors,the biomineralized microbial surface display technology was proposed.This review summarized the different microbial surface display systems and the biomineralized surface display systems,where the mechanisms of surface display and biomineralization were introduced.Then we described the recent progress of their applications on biosensors for different types of detection targets.Finally,the outlooks and tendencies were discussed and forecasted with the expectation to provide some general functions and enlightenments to this aspect of research.

Three-Dimensional Volumetric Analysis of Venous Malformations for Assessing the Effectiveness of Percutaneous Sclerotherapy

BACKGROUND Percutaneous sclerotherapy can be used to successfully treat venous malformations(VMs)of the head,neck,and limbs.However,the standard curative effect of sclerotherapy has rarely been analyzed,and there is currently no accurate statistical method to measure the volume of VMs after sclerotherapy.Here,we propose a novel threedimensional(3D)reconstruction method to evaluate this effect.OBJECTIVE To test the feasibility of 3D software(MIMICS 19.0)to evaluate the treatment effect of sclerotherapy.METHODS This retrospective study included patients with VMs on the head,neck,and limbs who were treated with ethanol sclerotherapy or foam sclerotherapy every 8 weeks.MIMICS 19.0 was used to calculate the performance of the lesion after treatment and measure the VM volumes before and after the treatment.The effect of the clinical treatment dose on the lesion was evaluated,and the treatment effect of each patient was recorded.The relationship between the number of treatments and the reduced volume of VMs was analyzed.RESULTS Based on the MIMICS-calculated regions of interest(ROI),we found that 1 mL of ethanol reduced the lesion by 473 mm3 and that one dosage of foam(1 mL of polidocanol and 4 mL air content)reduced the lesion by 2138 mm3,demonstrating that the foam sclerosing agent exhibited greater efficacy in this study.CONCLUSIONS The MIMICS 3D volume reconstruction method can effectively and safely evaluate the efficacy of sclerotherapy and provide a preoperative evaluation.This method is simple,accurate,and feasible.

Three-dimensional digital technology-assisted precise tumor resection and reconstruction of the femoral trochanter and postoperative functional recovery:a retrospective study

Background The trochanter of the femur is a common site for bone tumors.However,locating the specificboundary of bone tumor infiltration and determining the surgical method can be challenging.The objective of thisstudy was to review the diagnosis,treatment,and surgical outcomes of patients with tumors or tumor-like changesin the femoral trochanter after computer-assisted precise tumor resection and hip-preserving reconstruction ofthe trochanter.Methods From January 2005 to September 2020,11 patients with trochanteric tumors(aged:18–53 years;sixmales and five females)were treated in Guangzhou First People’s Hospital.The cases included aneurysmal bonecyst(n=1),giant cell tumor of bone(n=2),fibrous histiocytoma of bone(n=1),endochondroma(n=1),andfibrous dysplasia of bone(n=6).For patients with trochanteric tumors,computed tomography and magnetic resonance imaging scanning were performed before operation to obtain two-dimensional image data of the lesion.Athree-dimensional digital model of bilateral lower limbs was reconstructed by computer technology,the boundary of tumor growth was determined by computer simulation,the process of tumor resection and reconstructionwas simulated,and the personalized guide template was designed.During the operation,the personalized guideplate guided the precise resection of the tumor,and the allogeneic bone was trimmed to match the shape of thebone defect.Results All 11 patients underwent accurate resection of the tumor or tumor-like lesion and reconstruction ofthe hip.In eight cases,the lesion was confined to the trochanter,which was fixed with large segment allogeneicbone,autologous iliac bone,and proximal femoral anatomic plate.In three cases,allogeneic bone,autologousiliac bone,and femoral reconstruction nail were used to fix the tumor under the trochanter.Postoperative Xray examination showed that the repair and reconstruction of the bone defect was effective,and callus bridgingbetween the allogenic bone and autogenous bone was observed 6 months after operation.All patients recoveredtheir walking function 3–6 months after operation.The duration of the follow-up period ranged from 6 monthsto 6 years.A patient experienced recurrence of endochondroma;pathological examination revealed chondrocyticsarcoma.The remaining 10 patients were treated with segmental resection and reconstruction.The operationtime ranged 2.5–4.5 h(average:3.2 h).Intraoperative blood loss ranged from 300 to 500 ml(average:368 ml).The local recurrence rate was 9.1%,and the overall survival rate was 100%.The average Musculoskeletal TumorSociety score was 27(excellent and good for eight and three patients,respectively).Conclusions Three-dimensional computer skeleton modeling and simulation-assisted resection and reconstruction of femoral trochanteric tumor is a new surgical technique,which might markedly improve the surgical effect,shorten the surgical time,increase the overall survival rate of patients with tumors,reduce the local recurrencerate,assist in the digitization and programming of femoral trochanteric tumor surgery,and improve surgicalaccuracy.

Three-dimensional display technologies in wave and ray optics: a review(Invited Paper)

Multiple three-dimensional （3D） display technologies are reviewed. The display mechanisms discussed in this paper are classified into two categories： holographic display in wave optics and light field display in ray optics, which present the 3D optical wave field in two different ways. Key technical characteristics of the optical systems and the depth cues of human visual system are analyzed. It is to be expected that these 3D display technologies will achieve practical applications with the increase of the optical system bandwidth.

Opportunities and challenges of three-dimensional printing technology in pharmaceutical formulation development

Three-dimensional printing is a technology that prints the products layer-by-layer,in which materials are deposited according to the digital model designed by computer aided design(CAD)software.This technology has competitive advantages regarding product design complexity,product personalization,and on-demand manufacturing.The emergence of 3 D technology provides innovative strategies and new ways to develop novel drug delivery systems.This review summarizes the application of 3 D printing technologies in the pharmaceutical field,with an emphasis on the advantages of 3 D printing technologies for achieving rapid drug delivery,personalized drug delivery,compound drug delivery and customized drug delivery.In addition,this article illustrates the limitations and challenges of 3 D printing technologies in the field of pharmaceutical formulation development.