scholarly journals Exemplification of Tomographic Method to Evaluate the Quality of Welded Joints Made from EN 5754-H22 Alloy

2016 ◽  
Vol 39 (1) ◽  
pp. 65-78
Author(s):  
Józef Błachnio ◽  
Artur Kułaszka ◽  
Marek Chalimoniuk ◽  
Piotr Woźny
Keyword(s):  
Welded Joints ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Computer Assisted ◽  
Ct Scanner ◽  
Computer Assisted Tomography ◽  
Tomographic Method ◽  
Industrial Ct ◽  
The Given

Abstract The quality of welded joints depends on many factors. The relevant standards stipulate technical conditions of welds quality assessment, which provides the basis for stating whether the given joint is compatible with the requirements or whether it is defective. In practice, making welded joints that are totally devoid of defects is extremely difficult. To conduct the control of inner structure of the given joint a non-destructive method with the application of industrial CT scanner might be applied. This modern diagnosing method combines the x-ray examination with advanced computer technology. The basic advantage of computer-assisted tomography consists in examining objects in three dimensions and the possibility to carry out three-dimensional reconstructions. The aim of this article is to discuss the use of this method to evaluate the quality of welded joints made of aluminium alloys. Capabilities of computer-assisted tomography were depicted by the case of weld probes constructed with TIG (ang. Tungsten Inert Gas) welding by different process variables. One has made the analysis of the quality of probes showing the smallest and the biggest internal and external welding defects.

scholarly journals Three-dimensional propagation in near-field tomographic X-ray phase retrieval

2016 ◽  
Vol 72 (2) ◽  
pp. 215-221 ◽  
Author(s):  
Aike Ruhlandt ◽  
Tim Salditt
Keyword(s):  
Phase Retrieval ◽  
Near Field ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Current Phase ◽  
Computationally Efficient ◽  
X Ray ◽  
Reconstruction Quality ◽  
Consistency Constraints

This paper presents an extension of phase retrieval algorithms for near-field X-ray (propagation) imaging to three dimensions, enhancing the quality of the reconstruction by exploiting previously unused three-dimensional consistency constraints. The approach is based on a novel three-dimensional propagator and is derived for the case of optically weak objects. It can be easily implemented in current phase retrieval architectures, is computationally efficient and reduces the need for restrictive prior assumptions, resulting in superior reconstruction quality.

Still rendering: An exploration of 3D technologies for painting and other conventional mediums

2020 ◽  
Vol 6 (1) ◽  
pp. 53-72 ◽  
Author(s):  
Caitlin Cheek
Keyword(s):  
Three Dimensional ◽  
Three Dimensions ◽  
Traditional Art ◽  
3D Software ◽  
Modern Technologies

Artists working in the field of animation, games and films are expected to have in-depth knowledge of three-dimensional (3D) software as well as traditional art principles. However, when it comes to creating conventional paintings, many artists have yet to use 3D computer imaging. 3D software expands beyond what is possible in other computer programmes such as Photoshop, InDesign or Illustrator by giving the creator access to unlimited potential in three dimensions. My work embraces these modern technologies, crossing the boundaries between new and old media, to inform the paintings I create with oil on canvas. I utilize 3D software to push the surreal yet realistic quality of a setting. In this article, I explore my work in the context of historical precedents and contemporary examples that combine conventional media and 3D computer imaging. Keeping up and creatively employing these technologies within conventional modes of painting presents an opportunity to push the boundaries of my art.

scholarly journals Virtual reality and augmented reality applications and simulation in vascular access management with three-dimensional visualization

2019 ◽  
Vol 20 (1_suppl) ◽  
pp. 65-70
Author(s):  
Itsuo Yokoyama ◽  
Tsuyosi Sarai ◽  
Toshinori Asai ◽  
Nobuyuki Kitou ◽  
Hirotaka Nozaki ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Augmented Reality ◽  
Vascular Access ◽  
Three Dimensional ◽  
Computer Assisted ◽  
Access Management ◽  
Computer Assisted Tomography ◽  
Graphics Software ◽  
Anatomical Information ◽  
Tomography Scan

Obtaining adequate and precise anatomical information is mandatory to prevent vascular access–related complications in dialysis patients. For this purpose, we underwent Doppler ultrasound, vascular access angiogram, and plain computer-assisted tomography scan of the arm with vascular access. With the use of computer graphics software, the anatomical structure of the vascular access can be visualized three dimensionally which is shared among the staffs for precise and better recognition. Furthermore, created object is applicable for virtual reality and/or augmented reality presentation that provides useful means for education and practical procedures in the management of vascular access.

False ankylosis of the temporomandibular joint in a cat

2015 ◽  
Vol 28 (06) ◽  
pp. 455-458 ◽  
Author(s):  
N. Jamet ◽  
L. Larguier
Keyword(s):  
3D Reconstruction ◽  
Temporomandibular Joint ◽  
Objective Assessment ◽  
Three Dimensional ◽  
Computer Assisted ◽  
Office Visits ◽  
Computer Assisted Tomography ◽  
Postoperative Physical Therapy ◽  
One Year ◽  
Joint Range

SummaryObjective: To describe the use of two- dimensional computer-assisted tomography (CT) with three-dimensional (3D) reconstruction in the diagnosis and planning of surgical treatment of a case of false ankylosis of the temporomandibular joint.Case report: A young European Shorthaired cat was presented with the complaint of inability to eat and open its jaws. A CT scan with 3D reconstruction allowed visualization of the lesion which was causing extra- articular ankylosis of the temporomandibular joint. Surgery was performed to resect an osseous lesion of the zygomatic arch, thus freeing the temporomandibular joint. Postoperative physical therapy was initiated immediately following surgery, and then carried out by the owner with a one year follow-up. Clinical examination of the cat was performed during regular office visits (at 1 month and 3 months following surgery), which allowed objective assessment of postoperative recuperation. At the end of a year, the owners reported that the cat had maintained sufficient jaw opening without any signs consistent with chronic pain.Conclusion: Computed tomography scan with 3D reconstruction allowed planning of the surgical correction of extra-articular ankylosis of the temporomandibular joint, and in this case condylectomy was avoided, since temporomandibular joint range-of-motion was maintained.

scholarly journals Automatic Disassembly and Total Ordering in Three Dimensions

1991 ◽  
Vol 113 (2) ◽  
pp. 207-213 ◽  
Author(s):  
T. C. Woo ◽  
D. Dutta
Keyword(s):  
Three Dimensional ◽  
Single Component ◽  
Boundary Representation ◽  
Tree Structure ◽  
Three Dimensions ◽  
Robot Motion ◽  
Geometric Complexity ◽  
Minimal Sequence ◽  
The Given

Generating a sequence of motions for removing components in a three-dimensional assembly, one at a time, is considered—the robot motion being strictly translational. We map the boundary representation of a given assembly to a tree structure called Disassembly Tree (DT). Traversing the DT in pre- and post-order yields a minimal sequence of operations for disassembly and assembly, respectively. In this paper, an assembly is classified by the logical complexity of its DT (an ordered graph whose nodes are components of the given assembly) and by the geometric complexity of the nodes in DT (in terms of the number of motions needed to remove a single component). Next, whether a component can be removed in one motion is described as a predicate. This predicate is then used in an algorithm for constructing the DT. For a class of assemblies that exhibit total ordering, the algorithm decides whether each component can be removed in a single motion, by constructing a DT in O(N log N) time, on the average, where N is the total number of mating faces in the assembly.

scholarly journals Reconstruction of crystal shapes by X-ray nanodiffraction from three-dimensional superlattices

2014 ◽  
Vol 47 (6) ◽  
pp. 2030-2037 ◽  
Author(s):  
Mojmír Meduňa ◽  
Claudiu V. Falub ◽  
Fabio Isa ◽  
Daniel Chrastina ◽  
Thomas Kreiliger ◽  
...  
Keyword(s):  
Structural Model ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Semiconductor Layer ◽  
Dimensional Structure ◽  
Solid State Lasers ◽  
X Ray ◽  
Nondestructive Imaging ◽  
Low Dimensional

Quantitative nondestructive imaging of structural properties of semiconductor layer stacks at the nanoscale is essential for tailoring the device characteristics of many low-dimensional quantum structures, such as ultrafast transistors, solid state lasers and detectors. Here it is shown that scanning nanodiffraction of synchrotron X-ray radiation can unravel the three-dimensional structure of epitaxial crystals containing a periodic superlattice underneath their faceted surface. By mapping reciprocal space in all three dimensions, the superlattice period is determined across the various crystal facets and the very high crystalline quality of the structures is demonstrated. It is shown that the presence of the superlattice allows the reconstruction of the crystal shape without the need of any structural model.

Growth and Stability of Thrombi in Flowing Citrated Blood: Assessment of Platelet-Surface Interactions with Computer-Assisted Morphometry

1988 ◽  
Vol 60 (03) ◽  
pp. 392-398 ◽  
Author(s):  
Kjell S Sakariassen ◽  
Herbert Kuhn ◽  
Reto Muggli ◽  
Hans R Baumgartner
Keyword(s):  
Blood Flow ◽  
Platelet Adhesion ◽  
Three Dimensional ◽  
Blood Stream ◽  
Three Dimensions ◽  
Computer Assisted ◽  
Platelet Surface ◽  
Shear Rates ◽  
Perfusion Studies ◽  
En Face

SummaryThe differential quantitation of platelet deposition in perfusion studies is a major problem. We report on methods to prepare semithin sections of platelet deposits on collagen coated on glass and plastic cover slips, to study growth and stability of thrombi in three dimensions, and the development of a computer-assisted differential quantitation of platelet-collagen interactions. The interactions were quantified as percentage of the surface covered with platelets (platelet adhesion), thrombus height, thrombus density and thrombus area per unit sectional length, respectively.Cover slips coated with fibrillar equine collagen in parallelplate perfusion chambers were exposed to flowing citrated blood at shear rates ranging from 200 to 2,600 s−1. Thrombi, partially enmeshed in the collagen meshwork, prevailed on the surface at all shear rates. Maximal platelet adhesion and thrombus density were seen at >5 μg/cm2 collagen, while thrombus area and height were maximal at >10 μg/cm2. The volume of the thrombi appeared correlated to the number of deposited platelets (r = 0.92). En face preparations showed deposits of platelet islands which grew in diameter with time, particularly in the direction of the blood flow, becoming progressively confluent. Sections cut parallel to the direction of the blood stream indicated that this growth pattern was at least partially caused by thrombi bent in the direction of the blood flow. This view is consistent with data from corresponding sections cut perpendicular to the direction of the blood flow showing that the initial thrombus growth at 2 min is isotropic, while anisotropic growth, characterized with decreased growth in height, is observed at 5 and 10 min.Our three-dimensional analysis suggests that the growth occurs mainly in height, and that blood shear forces may bend the thrombi toward the surface resulting in platelet thrombi preferentially elongated in the direction of the blood flow.

scholarly journals Dear Computer on My Desk, Which Candidate Fits Best? An Assessment of Candidates’ Perception of Assessment Quality When Using AI in Personnel Selection

2021 ◽  
Vol 12 ◽  
Author(s):  
Jessica Schick ◽  
Sebastian Fischer
Keyword(s):  
Personnel Selection ◽  
Selection Process ◽  
Three Dimensional ◽  
Perceived Quality ◽  
Candidate Selection ◽  
Three Dimensions ◽  
Selection Procedures ◽  
Selection Processes ◽  
Candidate Perceptions

Recently, with the increase in technological capabilities and the need to reduce bias in candidate selection processes, artificial intelligence (AI)-based selection procedures have been on the rise. However, the literature indicates that candidate reactions to a selection process need to be considered by organizations that compete for employees. In this study, we investigate reactions to AI-based selection procedures in a three-dimensional vignette study among young adults in Germany. By investigating the effects of the dimensions of AI complexity, intangibility, and reliability on the perceived quality of assessment of potential candidates, we found that AI complexity and intangibility impact the perceived quality of assessment negatively when the candidates’ knowledge, strengths, and weaknesses should be assessed. We also found interactive relationships of all three dimensions for the assessment of motivation. In sum, results indicate that candidates are skeptical toward the assessment quality of AI-intense selection processes, especially if these assess complex assessment criteria such as personality or a job performance forecast. Hence, organizations need to be careful when implementing AI-based selection procedures. HR implications are made on the basis of these results to cope with negative candidate perceptions.

scholarly journals COMPUTER VISION PHOTOGRAMMETRY FOR UNDERWATER ARCHAEOLOGICAL SITE RECORDING IN A LOW-VISIBILITY ENVIRONMENT

2015 ◽  
Vol XL-5/W5 ◽  
pp. 231-238 ◽  
Author(s):  
T. Van Damme
Keyword(s):  
Computer Vision ◽  
Three Dimensional ◽  
Archaeological Site ◽  
Three Dimensions ◽  
Recording Efficiency ◽  
Low Visibility ◽  
Manual Recording ◽  
Underwater Sites ◽  
Near Future

Computer Vision Photogrammetry allows archaeologists to accurately record underwater sites in three dimensions using simple twodimensional picture or video sequences, automatically processed in dedicated software. In this article, I share my experience in working with one such software package, namely PhotoScan, to record a Dutch shipwreck site. In order to demonstrate the method’s reliability and flexibility, the site in question is reconstructed from simple GoPro footage, captured in low-visibility conditions. Based on the results of this case study, Computer Vision Photogrammetry compares very favourably to manual recording methods both in recording efficiency, and in the quality of the final results. In a final section, the significance of Computer Vision Photogrammetry is then assessed from a historical perspective, by placing the current research in the wider context of about half a century of successful use of Analytical and later Digital photogrammetry in the field of underwater archaeology. I conclude that while photogrammetry has been used in our discipline for several decades now, for various reasons the method was only ever used by a relatively small percentage of projects. This is likely to change in the near future since, compared to the ‘traditional’ photogrammetry approaches employed in the past, today Computer Vision Photogrammetry is easier to use, more reliable and more affordable than ever before, while at the same time producing more accurate and more detailed three-dimensional results.

scholarly journals Three-dimensional analysis of effects of rapid maxillary expansion on facial sutures and bones: A systematic review

2013 ◽  
Vol 83 (6) ◽  
pp. 1074-1082 ◽  
Author(s):  
Farhan Bazargani ◽  
Ingalill Feldmann ◽  
Lars Bondemark
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Case Series ◽  
Rapid Maxillary Expansion ◽  
Three Dimensions ◽  
Cochrane Library ◽  
Inclusion Criteria ◽  
Maxillary Expansion ◽  
Prospective Case Series

ABSTRACTObjective:To evaluate the evidence on three-dimensional immediate effects of rapid maxillary expansion (RME) treatment on growing patients as assessed by computed tomography/cone beam computed tomography (CT/CBCT) imaging.Materials and Methods:The published literature was searched through the PubMed, Embase, and Cochrane Library electronic databases from January 1966 to December 2012. The inclusion criteria consisted of randomized controlled trials, prospective controlled studies, and prospective case-series. Two reviewers extracted the data independently and assessed the quality of the studies.Results:The search strategy resulted in 73 abstracts or full-text articles, of which 10 met the inclusion criteria. When treating posterior crossbites with a RME device, the existing evidence points out that the midpalatal suture opening is around 20%–50% of the total screw expansion. There seems to be no consistent evidence on whether the midpalatal sutural opening is parallel or triangular. The effect on the nasal cavity dimensions after RME seems to be apparent and indicates an enlargement between 17% and 33% of the total screw expansion. Circummaxillary sutures, particularly the zygomaticomaxillary and frontomaxillary sutures and also spheno-occipital synchondrosis, appear to be affected by the maxillary expansion. Overall, however, the changes were small and the evidence not conclusive.Conclusions:CT imaging proved to be a useful tool for assessment of treatment effects in all three dimensions. The majority of the articles were judged to be of low quality, and therefore, no evidence-based conclusions could to be drawn from these studies.

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