Preliminary 3D Model Research Articles

METHOD OF ANALYSIS OF THE STRESS-STRAIN STATE OF A BASE-CENTERING DEVICE AND A PIPELINE WHEN CARRYING OUT THE COMPLEX OF EMERGENCY AND RECOVERY REPAIRS

Link for citation: Rakhmatullina Yu.A., Alekseev V.A., Sultanmagomedov T.S., Khasanov R.R. Method of analysis of the stress-strain state of a base-centering device and a pipeline when carrying out the complex of emergency and recovery repairs. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 7, рр.7-16. In Rus. The relevance of the research is caused by the need to carry out calculations of the stress-strain state of the support-centering device and the pipeline, when the device under consideration is exposed to it, when the axes are displaced due to the presence of residual stresses when carrying out a complex of emergency repair by cutting out a defective section of the pipeline. The purpose of the study is to assess the possibility of using the design of the device and to calculate the stress-strain state of the device when the axes of the boundary sections of the pipeline are displaced due to the release of prestresses during the emergency repair complex for cutting out the defective section of the pipeline. Methods: methods of classical theoretical mechanics, soil mechanics, finite element method. Results. Based on the patent, a preliminary 3D model of the support-centering device and a method for analyzing the boundary conditions and loads affecting the device and the pipeline during the emergency repair complex were developed. The calculation of SSS (stress-strain state) was carried out, where the following results were obtained: when the frame is displaced down/up by 100 mm in the device, respectively, along the length and displacement, stresses arise at the junctions of the enclosing ring and the frame, as well as on the «lugs», exceeding the yield strength of steel; the coefficient of friction μ for the considered diameter of 1020 mm should not exceed 0,15 to prevent the occurrence of areas of plastic deformation of the pipeline during the emergency repair complex for cutting out a defective area in swamp conditions.

The Use of Gigapixel Photogrammetry for the Understanding of Landslide Processes in Alpine Terrain

The work in this paper illustrates an experimental application for geosciences by coupling new and low cost photogrammetric techniques: Gigapixel and Structure-from-Motion (SfM). Gigapixel photography is a digital image composed of billions of pixels (≥1000 megapixels) obtained from a conventional Digital single-lens reflex camera (DSLR), whereas the SfM technique obtains three-dimensional (3D) information from two-dimensional (2D) image sequences. The field test was carried out at the Ingelsberg slope (Bad Hofgastein, Austria), which hosts one of the most dangerous landslides in the Salzburg Land. The stereographic analysis carried out on the preliminary 3D model, integrated with Ground Based Synthetic Aperture Radar Interferometry (GBInSAR) data, allowed us to obtain the main fractures and discontinuities of the unstable rock mass.

Visualization of the medical imaging data in 3D space using portable format

Medical imaging is a set of specific examination procedures taking advantage of physical effects for determination of changes that occurred in patient’s body. It’s a domain of biomedical engineering to define the methods of acquiring, analyzing and visualizing medical images in the way useful for diagnostic, therapeutic, educational or research purposes. This work describes an effective method of automatic creation of 3D objects from the DICOM images. At the beginning DICOM images are read. Then tissues are segmented with a simple thresholding algorithm and filtered. After filtering preliminary 3D model is created. Afterwards obtained geometry is smoothed and decimated to relax the model and reduce the size of data. Such prepared model is embedded into PDF file with use of additional scripts. As the result of this work software called DICOM2PDF3D, combining described above stages of building 3D model in a single procedure, was developed. With use of 3D PDF additional measurements of created geometry were made. Measurements confirmed values obtained from standard preoperative evaluation. The presented solution allows creating and opening three-dimensional visualizations on every desktop computer even by inexperienced users. Created 3D PDF can be used for preoperative evaluation as an assistance for standard procedures.

The magnetosphere of the close accreting PMS binary V4046 Sgr

V4046 Sagittarii AB is a close short-period classical T Tauri binary. It is a circularised and synchronised system accreting from a circumbinary disk. In 2009 it was observed as part of a coordinated program involving near-simultaneous spectropolarimetric observations with ESPaDOnS at the Canada-France-Hawai’i Telescope and high-resolution X-ray observations with XMM-Newton. Magnetic maps of each star were derived from Zeeman-Doppler imaging. After briefly highlighting the most significant observational findings, we present a preliminary 3D model of the binary magnetosphere constructed from the magnetic maps using a newly developed binary magnetic field extrapolation code. The large-scale fields (the dipole components) of both stars are highly tilted with respect to their rotation axes, and their magnetic fields are linked.

Crustal geometry of the central Skellefte district, northern Sweden – constraints from reflection seismic investigations

The Palaeoproterozoic Skellefte mining district in Sweden is one of the most important mining districts in Europe. As a part of a 4D geologic modeling project, three new sub-parallel reflection seismic profiles, with a total length of about 95km, were acquired in the central part of the district. Processed seismic data reveal a series of gentle- to steeply- dipping reflections and a series of diffraction packages. The majority of reflections that extend to the surface can be correlated with geological features either observed in the field or interpreted from the aeromagnetic map. A set of south-dipping reflections represent inferred syn-extensional listric extensional faults that were inverted during subsequent crustal-shortening. Cross-cutting north-dipping reflections are correlated to late-compressional break-back faults. Flat-lying reflections in the central parts of the study area could represent lithological contacts within the Skellefte Group, or the contact between Skellefte Group rocks and their unknown basement. Flat-lying reflections occurring further north are inferred to originate from the top of the Jörn intrusive complex or an intrusive contact within it. So far unknown south- and north-dipping faults have been identified in the vicinity of the Maurliden deposit. Based on the seismic results, a preliminary 3D-model has been created in order to visualize the fault pattern and to provide a base for future 3D/4D modeling in the Skellefte district.

Fusing Multiview and Photometric Stereo for 3D Reconstruction under Uncalibrated Illumination

We propose a method to obtain a complete and accurate 3D model from multiview images captured under a variety of unknown illuminations. Based on recent results showing that for Lambertian objects, general illumination can be approximated well using low-order spherical harmonics, we develop a robust alternating approach to recover surface normals. Surface normals are initialized using a multi-illumination multiview stereo algorithm, then refined using a robust alternating optimization method based on the l(1) metric. Erroneous normal estimates are detected using a shape prior. Finally, the computed normals are used to improve the preliminary 3D model. The reconstruction system achieves watertight and robust 3D reconstruction while neither requiring manual interactions nor imposing any constraints on the illumination. Experimental results on both real world and synthetic data show that the technique can acquire accurate 3D models for Lambertian surfaces, and even tolerates small violations of the Lambertian assumption.

Purification, Cloning, and Three-Dimensional Structure Prediction of Micrococcus luteus FAD-Containing Tyramine Oxidase

The FAD-containing tyramine oxidase enzyme and gene from the Gram (+) bacterium Micrococcus luteus were isolated, and computer prediction was used to propose a preliminary 3D model of the protein. A 2.8-kb Sau3AI fragment containing the structural gene of tyramine oxidase was cloned from a M. luteus genomic DNA library. The 1332 bp gene encodes a protein of 443 amino acids, with a calculated molecular mass of 49.1 kDa. The enzyme was found to be a homodimer with a molecular weight of 49,000. It oxidizes tyramine, adrenaline, 3-hydroxytyramine, dopamine, and noradrenaline, and was reversibly inhibited by FAD-containing monoamine oxidase A and B specific inhibitors. Sequence comparison show that tyramine oxidase is smaller than other FAD-amine oxidases but that it contains well-conserved amino acid residues reported in all other FAD-amine oxidases. A hypothetical three-dimensional structure of tyramine oxidase has also been proposed based on secondary structure predictions, threading, and comparative modeling.

SWEET - WWW-based rapid 3D construction of oligo- and polysaccharides.

SWEET is a WWW-based tool which rapidly converts the commonly used carbohydrate sequence information directly into a preliminary but reliable 3D model which can be visualised and written to files in several ways. SWEET is accessible via the Internet at http://www.dkfz-heidelberg.de/spec/. a. bohne@dkfz-heidelberg.de or w.vonderlieth@ dkfz-heidelberg.de The current version of SWEET generates only one conformation out of a manifold. Several authors have analysed possible conformations of high-mannose N-linked glycans using a combination of NMR methods and computational approaches showing that such molecules are rather flexible populating normally several conformations for each glycosidic linkage. The displayed model exhibits for all glycosidic linkages a conformation which is in accordance with the reported variations of Phi, psi and omega values for specific linkage (see http://www.dkfz-heidelberg. de/spec/sweet2/doc/input/sba_example.html).

W3-SWEET: Carbohydrate Modeling By Internet

The software tool SWEET accessible through Internet is described which rapidly converts the commonly used sequence information of complex carbohydrates directly into a preliminary but reliable 3D model. The basic idea is to link preconstructed 3D molecular templates of monosaccharides in a specific way of binding as defined in the sequence information. In a subsequent step a fast routine to explore the conformational space for each glycosidic linkage has been implemented. Systematic rotations around the glycosidic linkages are performed, calculating the van der Waals interactions for each step of rotation. The user interaction is supported by an input spreadsheet consisting of a grid of sugar symbol and connection type cells. Several ways to visualise and to output the generated structures and related information are implemented. Since interactivity is an absolute prerequisite for each WWW application, the limitations of the approach are discussed in detail. SWEET will open modelling techniques to a broader range of users, especially for those who do not have access to the required hard- and software equipment.

A preliminary 3D model for cytochrome P450 2D6 constructed by homology model building

A homology model building study of cytochrome P450 2D6 has been carried out based on the crystal structure of cytochrome P450 101. The primary sequences of P450 101 and P450 2D6 were aligned by making use of an automated alignment procedure. This alignment was adjusted manually by matching alpha-helices (C, D, G, I, J, K and L) and beta-sheets (beta 3/beta 4) of P450 101 that are proposed to be conserved in membrane-bound P450s (Ouzounis and Melvin [Eur. J. Biochem., 198 (1991) 307]) to the corresponding regions in the primary amino acid sequence of P450 2D6. Furthermore, alpha-helices B, B' and F were found to be conserved in P450 2D6. No significant homology between the remaining regions of P450 101 and P450 2D6 could be found and these regions were therefore deleted. A 3D model of P450 2D6 was constructed by copying the coordinates of the residues from the crystal structure of P450 101 to the corresponding residues in P450 2D6. The regions without a significant homology with P450 101 were not incorporated into the model. After energy-minimization of the resulting 3D model of P450 2D6, possible active site residues were identified by fitting the substrates debrisoquine and dextrometorphan into the proposed active site. Both substrates could be positioned into a planar pocket near the heme region formed by residues Val370, Pro371, Leu372, Trp316, and part of the oxygen binding site of P450 2D6. Furthermore, the carboxylate group of either Asp100 or Asp301 was identified as a possible candidate for the proposed interaction with basic nitrogen atom(s) of the substrates.(ABSTRACT TRUNCATED AT 250 WORDS)