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Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by three-dimensional digital image correlation 被引量:15
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作者 H. Munoz A. Taheri 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第4期599-610,共12页
The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in sp... The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in specimens with different aspect ratios was also examined.Peak stress,post-peak portion of stress-strain,brittleness,characteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect ratio.Strain patterns of the rocks were obtained by applying three-dimensional(3D) digital image correlation(DIC) technique.Unlike conventional strain measurement using strain gauges attached to specimen,3D DIC allowed not only measuring large strains,but more importantly,mapping the development of field strain throughout the compression test,i.e.in pre-and post-peak regimes.Field strain development in the surface of rock specimen suggests that strain starts localising progressively and develops at a lower rate in pre-peak regime.However,in post-peak regime,strains increase at different rates as local deformations take place at different extents in the vicinity and outside the localised zone.The extent of localised strains together with the rate of strain localisation is associated with the increase in rate of strength degradation.Strain localisation and local inelastic unloading outside the localised zone both feature post-peak regime. 展开更多
关键词 Uniaxial compression test Aspect ratio Strain patterns digital image correlation(DIC)
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A three-dimensional digital visualization model of cervical nerves in a healthy person 被引量:1
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作者 Jiaming Cao Dong Fu Sen Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第20期1829-1836,共8页
Three-dimensional reconstruction nerve models are classically obtained from two-dimensional images of "visible human" frozen sections. However, because of the flexibility of nerve tissues and small color differences... Three-dimensional reconstruction nerve models are classically obtained from two-dimensional images of "visible human" frozen sections. However, because of the flexibility of nerve tissues and small color differences compared with surrounding tissues, the integrity and validity of nerve tissues can be impaired during milling. Thus, in the present study, we obtained two-dimensional data from a healthy volunteer based on continuous CT angiography and magnetic resonance myelography. Semi-automatic segmentation and reconstruction were then conducted at different thresholds in different tissues using Mimics software. Small anatomical structures such as muscles and cervical nerves were reconstructed using the medical computer aided design module. Three-dimensional digital models of the cervical nerves and their surrounding structures were successfully developed, which allowed visualization of the spatial relation of anatomical structures with a strong three-dimensional effect, distinct appearance, clear distribution, and good continuity, precision, and integrality. These results indicate the validity of a three-dimensional digital visualization model of healthy human cervical nerves, which overcomes the disadvantages of milling, avoids data loss, and exhibits a realistic appearance and three-dimensional image. 展开更多
关键词 neural regeneration CERVICAL three-dimension CT magnetic resonance myelography cervical plexus phrenic nerve vagus nerve recurrent laryngeal nerve GANGLION stellate ganglion grants-supported paper NEUROREGENERATION
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Evaluation of Maxillary Dental Arch Widths in Individuals Having Unilateral and Bilateral Cleft Lip and Palate Using Three-Dimensional Digital Models
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作者 Ege Dogan Abdü +2 位作者 lkadir Iş ik Servet Dogan 《Open Journal of Stomatology》 2019年第7期159-167,共9页
Aim: Maxillary dental arch widths were evaluated in individuals having unilateral (UCLP) and bilateral (BCLP) cleft lip and palate (CLP) using three-dimensional (3D) digital models. Material and Method: The study had ... Aim: Maxillary dental arch widths were evaluated in individuals having unilateral (UCLP) and bilateral (BCLP) cleft lip and palate (CLP) using three-dimensional (3D) digital models. Material and Method: The study had been conducted on 80 individuals aged between 14 - 17 years having UCLP and BCLP. 40 of the individuals had UCLP, whereas 40 had BCLP. The maxillary dental models taken from patients before the treatment were scanned using Orthomodel Programme (v.1.01, Orthomodel Inc., Istanbul, Turkey) to obtain 3D imagery. Student’s t-test was used in order to assess the data obtained by using SPSS software version 22.0. Results: In BCLP, the average inter-canine distance was 17.44 ± 1.31 mm, the average inter-molar distance was 36.57 ± 1.12 mm, while inter-canine/inter-molar ratio was 0.47. Whereas in UCLP, it was 25.10 ± 0.63 mm, 42.20 ± 0.53 mm and 0.59. The inter-canine distance in UCLP was found to be large enough to be statistically significant (p 0.05), even though there were differences in inter-molar widths. Conclusion: For the stable orthodontic treatment results, one of the most important points is arch form and widths to be coherent with each other. In our study, the increase of inter-canine distance seen in UCLP indicates that in the cleft region, the maxillary arch is inclined over to the back, while the same situation in BCLP suggests that the maxillary segments are collapsed inside. The difference in the arch is highly affected by the primary surgical treatment. 展开更多
关键词 UNILATERAL CLEFT LIP and PALATE Bilateral CLEFT LIP and PALATE three-dimensional digital Models
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Digital reconstruction of three-dimensional contours and its application to microstructural evaluation of postblast rock fissure surfaces
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作者 Yanbing Wang Zhaoyang Wang +1 位作者 Dairui Fu Mingwei Gang 《Deep Underground Science and Engineering》 2025年第2期316-328,共13页
Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstructi... Fracture surface contour study is one of the important requirements for characterization and evaluation of the microstructure of rocks.Based on the improved cube covering method and the 3D contour digital reconstruction model,this study proposes a quantitative microstructure characterization method combining the roughness evaluation index and the 3D fractal dimension to study the change rule of the fracture surface morphology after blasting.This method was applied and validated in the study of the fracture microstructure of the rock after blasting.The results show that the fracture morphology characteristics of the 3D contour digital reconstruction model have good correlation with the changes of the blasting action.The undulation rate of the three-dimensional surface profile of the rock is more prone to dramatic rise and dramatic fall morphology.In terms of tilting trend,the tilting direction also shows gradual disorder,with the tilting angle increasing correspondingly.All the roughness evaluation indexes of the rock fissure surface after blasting show a linear and gradually increasing trend as the distance to the bursting center increases;the difference between the two-dimensional roughness evaluation indexes and the three-dimensional ones of the same micro-area rock samples also becomes increasingly larger,among which the three-dimensional fissure roughness coefficient JRC and the surface roughness ratio Rs display better correlation.Compared with the linear fitting formula of the power function relationship,the three-dimensional fractal dimension of the postblast fissure surface is fitted with the values of JRC and Rs,which renders higher correlation coefficients,and the degree of linear fitting of JRC to the three-dimensional fractal dimension is higher.The fractal characteristics of the blast-affected region form a unity with the three-dimensional roughness evaluation of the fissure surface. 展开更多
关键词 cube covering method evaluation of damage characterization fractal dimension roughness three-dimensional contour scanning
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Precise 3D shape measurement of three-dimensional digital image correlation for complex surfaces 被引量:3
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作者 YAN TianHao SU Yong ZHANG QingChuan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第1期68-73,共6页
Three dimensional-digital image correlation (3D-DIC) is a widely used optical metrology in the experimental mechanics community because of its reliability, practicality, and flexibility. Although the precision of di... Three dimensional-digital image correlation (3D-DIC) is a widely used optical metrology in the experimental mechanics community because of its reliability, practicality, and flexibility. Although the precision of digital image correlation (DIC) has been thoroughly studied theoretically and numerically, verification experiments have seldom been performed, especially fbr complex surfaces with a small field of view (FOV). In this work, the shape of a 1-yuan coin was measured using 3D-DIC; the shape was complex due to the presence of many fine details, and the FOV was relatively small because the coin diameter was only 25 mm. During the experiment, a novel strategy for speckle production was developed: white paint was simply sprayed onto the surface. Black paint was not used; instead, taking advantage of the reflective nature of the coin surface, polarized light and a Polaroid filter were introduced, and the polarization direction was carefully adjusted, ensuring that the spray pattern was extremely thin and that high-quality speckle images with significant contrast were captured. The three-dimensional coin shape was also successfully determined for comparison using a stylus profiler. The results demonstrate that 3D-DIC provides high precision in shape measurement even for complex surfaces with small FOV. The precision of 3D-DIC can reach 1/7000 of the field of view, corresponding to about 6 ~tm in this experiment. 展开更多
关键词 three-dimensional digital image correlation(3D-DIC) measurement precision complex surfaces small field of view polarized light polaroid filter
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Three-dimensional digital technology-assisted precise tumor resection and reconstruction of the femoral trochanter and postoperative functional recovery:a retrospective study
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作者 Yuanhai Tu Yuanhao Peng +4 位作者 Xinghua Wen Yuning Wang Kang Liu Kai Cheng Han Yan 《Intelligent Medicine》 EI CSCD 2023年第4期235-242,共8页
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 thisstud... 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. 展开更多
关键词 three-dimensional digital technology Bone tumor Femoral trochanteric Surgical treatment Functional reconstruction
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Mapping research trends and competency domains in nursing-related digital and artificial intelligence technologies:A bibliometric analysis
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作者 Kanjanee Phanphairoj Wasinee Wisesrith Sutthisan Chumwichan 《International Journal of Nursing Sciences》 2026年第1期36-44,I0003,I0004,共11页
Objectives This study aimed to explore the research trends,thematic structures,and core competency domains in the field of nursing-related digital and artificial intelligence(AI)technologies.Methods A bibliometric ana... Objectives This study aimed to explore the research trends,thematic structures,and core competency domains in the field of nursing-related digital and artificial intelligence(AI)technologies.Methods A bibliometric analysis was conducted in accordance with the PRISMA 2020 statement.Peer-reviewed articles published in English from 2015 to 2025 were retrieved from Scopus,Web of Science,and PubMed.Thematic clustering was conducted using the Louvain algorithm and cosine similarity.A subset of 66 frequently cited articles was then qualitatively synthesized to capture core competencies across clusters.Results A total of 83,807 articles were included for bibliometric analysis.Of these,66 articles were chosen for thematic analysis.Five major thematic clusters were identified:remote care in primary settings,oncology and palliative care,nurse education and training,safety and quality in nursing practice,and geriatric and dementia care.Additionally,four competency domains were identified:telehealth and remote communication,health systems and informatics,digital tools in practice,and AI-powered decision support.A clear shift in research focus was observed,with the emphasis transitioning from foundational digital skills before the COVID-19 pandemic to more advanced competencies during the post-pandemic digital transformation,encompassing ethical reasoning,immersive technology use,and AI integration.Conclusions Integrating digital and AI technologies is reshaping nursing practice across various thematic areas and competency domains,highlighting a transition from foundational digital tasks to AI-supported decision-making and ethically informed technology use.This study provides a structured overview of evolving competencies in digital nursing and synthesizes evidence to support future research,curriculum design,and policy planning. 展开更多
关键词 Artificial intelligence competence Bibliometric analysis digital competence Nursing competency domains Post-pandemic digital transformation
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Detection Sensitivity of Chip Digital PCR for Staphylococcus aureus
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作者 Yunxia WANG Xiaxia HOU +1 位作者 Xiaoli WU Wang LIU 《Asian Agricultural Research》 2026年第1期46-50,60,共6页
[Objectives]This study aimed to evaluate the detection sensitivity of Staphylococcus aureus in dairy products utilizing the chip digital PCR(cdPCR)technique.[Methods]Specific primers and probes were designed and synth... [Objectives]This study aimed to evaluate the detection sensitivity of Staphylococcus aureus in dairy products utilizing the chip digital PCR(cdPCR)technique.[Methods]Specific primers and probes were designed and synthesized based on the conserved sequence of the heat-resistant nuclease gene nuc of S.aureus.cdPCR was employed to detect S.aureus,and the sensitivity of this technique was systematically assessed in samples exhibiting low levels of contamination.[Results]cdPCR demonstrated precise quantification when the initial concentration of the sample enrichment solution was equal to or greater than 50 CFU/mL.The detection dynamic range extended across at least five orders of magnitude,with a minimum DNA detection limit of 0.2304 pg/μL.In artificially contaminated cheese samples,the method s lower limit of quantification for detecting S.aureus was 8×10^(2) CFU/g.Regression analysis demonstrated that the gene copy number concentration measured by cdPCR exhibited a strong linear correlation with bacterial contamination concentration across a broad range.[Conclusions]The cdPCR method developed in this study demonstrates high sensitivity and robust quantitative capabilities,offering a reliable technical approach for the precise detection of low-level S.aureus contamination in dairy products. 展开更多
关键词 STAPHYLOCOCCUS AUREUS CHIP digital PCR (cdPCR) Sensitivity
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Preparation of digital-encoded and analog-encoded quantum states corresponding to matrix operations
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作者 Kaitian Gao Youlong Yang Zhenye Du 《Chinese Physics B》 2026年第1期332-344,共13页
Efficient implementation of fundamental matrix operations on quantum computers,such as matrix products and Hadamard operations,holds significant potential for accelerating machine learning algorithms.A critical prereq... Efficient implementation of fundamental matrix operations on quantum computers,such as matrix products and Hadamard operations,holds significant potential for accelerating machine learning algorithms.A critical prerequisite for quantum implementations is the effective encoding of classical data into quantum states.We propose two quantum computing frameworks for preparing the distinct encoded states corresponding to matrix operations,including the matrix product,matrix sum,matrix Hadamard product and division.Quantum algorithms based on the digital encoding computing framework are capable of implementing the matrix Hadamard operation with a time complexity of O(poly log(mn/ε))and the matrix product with a time complexity of O(poly log(mnl/ε)),achieving an exponential speedup in contrast to the classical methods of O(mn)and O(mnl).Quantum algorithms based on the analog-encoding framework are capable of implementing the matrix Hadamard operation with a time complexity of O(k_(1)√mn·poly log(mn/ε))and the matrix product with a time complexity of O(k_(2)√1·poly log(mnl/ε)),where k_(1)and k_(2)are coefficients correlated with the elements of the matrix,achieving a square speedup in contrast to the classical counterparts.As applications,we construct an oracle that can access the trace of a matrix within logarithmic time,and propose several algorithms to respectively estimate the trace of a matrix,the trace of the product of two matrices,and the trace inner product of two matrices within logarithmic time. 展开更多
关键词 quantum algorithm matrix operation digital and analog-encoded states quantum computing
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Oral wearable biochemical sensors:towards comfortable,intelligent,and networked digital health
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作者 Kai-Xiang Xu Xin-Yi Qu +1 位作者 Pui Wing Yap Jian-Hua Zhou 《Biomedical Engineering Communications》 2026年第2期1-3,共3页
Wearable sensors have revolutionized health monitoring by transitioning from clinical diagnostics to continuous,real-time applications in daily life.The oral cavity,rich in saliva containing over 1,000 biomarkers that... Wearable sensors have revolutionized health monitoring by transitioning from clinical diagnostics to continuous,real-time applications in daily life.The oral cavity,rich in saliva containing over 1,000 biomarkers that reflect systemic health(e.g.,glucose,cortisol,and inflammatory markers)[1],offers the advantage of non-invasive sampling.Its superior environmental stability and strong connection to key physiological processes make it an ideal candidate in the field of digital medicine,serving as a natural gateway to personalized health monitoring.Therefore,the oral cavity represents not only a convenient sampling site but also a strategic interface for realizing the vision of continuous,personalized digital health monitoring. 展开更多
关键词 SALIVA health monitoring clinical diagnostics oral cavityrich oral cavity natural gate wearable sensors digital medicineserving
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Hybrid AI-IoT Framework with Digital Twin Integration for Predictive Urban Infrastructure Management in Smart Cities
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作者 Abdullah Alourani Mehtab Alam +2 位作者 Ashraf Ali Ihtiram Raza Khan Chandra Kanta Samal 《Computers, Materials & Continua》 2026年第1期462-493,共32页
The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often... The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often advanced one dimension—such as Internet of Things(IoT)-based data acquisition,Artificial Intelligence(AI)-driven analytics,or digital twin visualization—without fully integrating these strands into a single operational loop.As a result,many existing solutions encounter bottlenecks in responsiveness,interoperability,and scalability,while also leaving concerns about data privacy unresolved.This research introduces a hybrid AI–IoT–Digital Twin framework that combines continuous sensing,distributed intelligence,and simulation-based decision support.The design incorporates multi-source sensor data,lightweight edge inference through Convolutional Neural Networks(CNN)and Long ShortTerm Memory(LSTM)models,and federated learning enhanced with secure aggregation and differential privacy to maintain confidentiality.A digital twin layer extends these capabilities by simulating city assets such as traffic flows and water networks,generating what-if scenarios,and issuing actionable control signals.Complementary modules,including model compression and synchronization protocols,are embedded to ensure reliability in bandwidth-constrained and heterogeneous urban environments.The framework is validated in two urban domains:traffic management,where it adapts signal cycles based on real-time congestion patterns,and pipeline monitoring,where it anticipates leaks through pressure and vibration data.Experimental results show a 28%reduction in response time,a 35%decrease in maintenance costs,and a marked reduction in false positives relative to conventional baselines.The architecture also demonstrates stability across 50+edge devices under federated training and resilience to uneven node participation.The proposed system provides a scalable and privacy-aware foundation for predictive urban infrastructure management.By closing the loop between sensing,learning,and control,it reduces operator dependence,enhances resource efficiency,and supports transparent governance models for emerging smart cities. 展开更多
关键词 Smart cities digital twin AI-IOT framework predictive infrastructure management edge computing reinforcement learning optimization methods federated learning urban systems modeling smart governance
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Three-dimensional visualization interactive system for digital twin workshop 被引量:8
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作者 Zhang Qinglei Yang Zhiwei +2 位作者 Duan Jianguo Liu Zhen Qin Jiyun 《Journal of Southeast University(English Edition)》 EI CAS 2021年第2期137-152,共16页
To improve the human-physical-virtual coordination and integration of the digital twin workshop,3D visual monitoring and human-computer interaction of the digital twin workshop was studied.First,a novel 6D model of th... To improve the human-physical-virtual coordination and integration of the digital twin workshop,3D visual monitoring and human-computer interaction of the digital twin workshop was studied.First,a novel 6D model of the 3D visualization interactive system for digital twin workshops is proposed.As the traditional 5D digital twin model ignores the importance of human-computer interaction,a new dimension of the user terminal was added.A hierarchical real-time data-driven mapping model for the workshop production process is then proposed.Moreover,a real-time data acquisition method for the industrial Internet of things is proposed based on OPC UA(object linking and embedding for process control unified architecture).Based on the 6D model of the system,the process of creating a 3D visualization virtual environment based on virtual reality is introduced,in addition to a data-driven process based on the data management cloud platform.Finally,the 6D model of the system was confirmed using the blade rotor test workshop as the object,and a 3D visualization interactive system is developed.The results show that the system is more transparent,real-time,data-driven and more efficient,as well as promotes the coordination and integration of human-physical-virtual,which has practical significance for developing digital twin workshops. 展开更多
关键词 digital twin workshop three-dimensional visualization human-computer interaction data driven OPC UA(object linking and embedding for process control unified architecture)
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Optical encryption of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography 被引量:2
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作者 Ying Wang Qi Liu +1 位作者 Jun Wang Qiong-Hua Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期253-259,共7页
We present an optical encryption method of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography. By modifying the Mach-Zehnder interferometer, the interference of the ... We present an optical encryption method of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography. By modifying the Mach-Zehnder interferometer, the interference of the multiple objects beams and the one reference beam is used to simultaneously encrypt multiple objects into a ciphertext. During decryption, each three-dimensional object can be decrypted independently without having to decrypt other objects. Since the single- pixel digital holography based on compressive sensing theory is introduced, the encrypted data of this method is effectively reduced. In addition, recording fewer encrypted data can greatly reduce the bandwidth of network transmission. Moreover, the compressive sensing essentially serves as a secret key that makes an intruder attack invalid, which means that the system is more secure than the conventional encryption method. Simulation results demonstrate the feasibility of the proposed method and show that the system has good security performance. 展开更多
关键词 multiple three-dimensional objects encryption single-pixel digital holography phase-shifting in- terference compressive sensing
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A combination of digital design and three-dimensional printing to assist treatment of thoracolumbar compression fractures using percutaneous kyphoplasty 被引量:2
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作者 Hui Lu Daixiang Jiang +1 位作者 Qimei Wu Rong Liu 《Global Health Journal》 2021年第4期190-193,共4页
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 tur... 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. 展开更多
关键词 Percutaneous kyphoplasty Thoracolumbar compression fracture digital design three-dimensional(3D)printing
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Three-Dimensional TIN Algorithm for Digital Terrain Modeling 被引量:7
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作者 ZHU Qing ZHANG Yeting LI Fengchun 《Geo-Spatial Information Science》 2008年第2期79-85,共7页
The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrai... The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrain surface modeling, a new algorithm for the automatic generation of three dimensional triangulated irregular network from a point cloud is pro- posed. Based on the local topological consistency test, a combined algorithm of constrained 3D Delaunay triangulation and region-growing is extended to ensure topologically correct reconstruction. This paper also introduced an efficient neighbor- ing triangle location method by making full use of the surface normal information. Experimental results prove that this algo- rithm can efficiently obtain the most reasonable reconstructed mesh surface with arbitrary topology, wherein the automati- cally reconstructed surface has only small topological difference from the true surface. This algorithm has potential applica- tions to virtual environments, computer vision, and so on. 展开更多
关键词 three dimensional triangulated irregular network digital terrain surface modeling Delaunay triangulation
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Application of three-dimensional digitalized reconstruction of latissimus dorsi myocutaneous flap
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作者 Yuanzhi ZHANG Jianwei LI +4 位作者 Yanbing LI Dan JIN Jionghao CHEN Shizhen ZHONG Guoxian PEI 《Frontiers of Medicine》 SCIE CSCD 2008年第1期45-50,共6页
Developments of digital technology and three-dimensional(3D)reconstruction allowed a precise description of anatomic structures.With the introduction of Visible Human Project and Virtual Chinese Human(VCH)techniques,m... Developments of digital technology and three-dimensional(3D)reconstruction allowed a precise description of anatomic structures.With the introduction of Visible Human Project and Virtual Chinese Human(VCH)techniques,more detailed anatomic images could be obtained.Digitized visible models of these structures can be applied as a useful tool in clinical training.The aim of this study was to reconstruct the normal structures of thoracodorsal artery in 3D images and to establish the digitized visible models of latissimus dorsi myocutaneous(LDM)flap.The cross-sectional images from the four VCH datasets were reviewed to study LDM and thoraco-dorsal artery structures on a section-by-section basis.Next,two adult fresh cadaver specimens were perfused with lead oxide-gelatine mixture and subject to radio-graphic CT scanning on their torsos.The cross-sectional images from the CT images were reviewed to study thor-acodorsal artery structures.Three-dimensional computer-ized reconstructions of LDM flap structures were conducted from these datasets by using Amira 3.1(TGS)software respectively.The 3D reconstructed visible models established from these datasets perfectly displayed the anatomic characteristics of LDM flap. 展开更多
关键词 latissimus dorsi myocutaneous IMAGING three-dimensional Virtual Chinese Human digital technique
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Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology
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作者 胡永成 《外科研究与新技术》 2011年第2期125-125,共1页
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 wer... 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 展开更多
关键词 BONE digital measurement of bone tumor volume by CT three-dimensional reconstruction technology CT
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Three-Dimensional Scenes Restore Using Digital Image
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作者 Takialddin Al Smadi Igried Al-Khawaldeh Kalid Al Smadi 《Journal of Signal and Information Processing》 2017年第1期1-8,共8页
Encryption and decryption method of three-dimensional objects uses holograms computer-generated and suggests encoding stage. Information obtained amplitude and phase of a three-dimensional object using mathematically ... Encryption and decryption method of three-dimensional objects uses holograms computer-generated and suggests encoding stage. Information obtained amplitude and phase of a three-dimensional object using mathematically stage transforms overlap stored on a digital computer. Different three-dimensional images restore and develop the system for the expansion of the three-dimensional scenes and camera movement parameters. This article talks about these kinds of digital image processing algorithms as the reconstruction of three-dimensional model of the scene. In the present state, many such algorithms need to be improved in this paper proposing one of the options to improve the accuracy of such reconstruction. 展开更多
关键词 three-dimensional SCENES RESTORE FACTORIZATION Method TRIANGULATION VRML Model Hybrid Algorithm
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使用Digital Wings扫描体的无牙颌种植口内扫描印模与传统印模的精确性比较
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作者 黄婧 陆沁怡 +1 位作者 徐鹏 梁源 《口腔医学研究》 北大核心 2025年第10期890-895,共6页
目的:探究Digital Wings新型扫描体对无牙颌种植口内扫描印模技术精度的影响,分析其在数字化口内扫描组中的表现,以及与传统印模技术的精度的差异,为临床应用提供参考。方法:使用最佳拟合法和绝对线性偏差法得到传统取模组、口内扫描组... 目的:探究Digital Wings新型扫描体对无牙颌种植口内扫描印模技术精度的影响,分析其在数字化口内扫描组中的表现,以及与传统印模技术的精度的差异,为临床应用提供参考。方法:使用最佳拟合法和绝对线性偏差法得到传统取模组、口内扫描组和标准模型组的种植体位置的准确性和精度有效值(root mean square,RMS)。结果:传统组、普通扫描体组、新型CAD扫描体组和Digital Wings扫描体组准确性的均方根RMS中位数(四分位间距)分别为39.3(29.9~50.5)μm、135.1(50.8~260.5)μm、84.3(53.2~212.5)μm、81.3(33.8~133.2)μm。Digital Wings扫描体组和传统取模组比较无显著性差异(P>0.05)。精度的RMS均数分别为35.3(12.4~98.5)μm、155.4(33.2~329.9)μm、116.4(4.4~349.8)μm、54.0(13.4~124.6)μm。Digital Wings扫描体组和新型CAD扫描体组与传统取模组比较无显著差异(P>0.05)。结论:Digital Wings扫描体组的精度和传统组的精度比较无显著差异。扫描体的改进,如扫描体外形的改变使扫描体的精度逐渐增加。更多关于无牙颌种植扫描体体外研究和临床研究需要开展。 展开更多
关键词 精度 准确性 digital Wings 扫描体 无牙颌
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