scholarly journals Macro-Modelling of Rib-Knitted Tubular Parts

Tekstilec ◽  
2021 ◽  
Vol 64 (4) ◽  
pp. 317-324
Author(s):  
Tetiana Ielina ◽  
◽  
Liudmyla Halavska ◽  
Nataliia Ausheva ◽  
◽  
...  
Keyword(s):  
Body Surface ◽  
Three Dimensional ◽  
3D Modelling ◽  
Structural Hierarchy ◽  
Truncated Cone ◽  
Thin Walled ◽  
Three Dimensional Models ◽  
Human Body Surface ◽  
Time Required ◽  
Stretching Process

The aim of the research was to improve the process of knitted products design. The use of modern software helps us predict the physical and mechanical behaviour of materials, using their three-dimensional models. A macro-model of rib-knitted tubular parts was developed in the study. This model allows its implementation into algorithms, describing the peculiarities of the stretching process. Recent findings in the field of 3D modelling and simulation of knitwear behaviour aim at working with models of different scales of structural hierarchy. The use of macro-models provides the opportunity to simplify the geometry and significantly reduce the time required for simulation. Rib stitch structures are among the most popular weft-knitted ones. When using threads of usual stretchability (with breaking elongation that does not exceed 10–12%), the stretchability of some rib stitch structures in the course-wise direction can reach up to 350% and even more. When stretched in the course direction, rib-knitted stitches undergo a number of stages. The stretching process includes: decreasing the width-wise curling; mutual shifting of knit and purl stitches; reducing the curvature of the loop feet and loop heads; pulling the yarn from the loop legs to the loop feet; stretching of the yarn. The assumption was made that such parts of knitted garments as cuffs and borders on sweaters, cuffs on socks, where rib stitch patterns are used, can be described as thin-walled elastic shells. A part of a human body surface, covered with a rib-knitted garment part, can be approximated by a truncated cone. The mid-surface of the shell can be represented as a ruled surface created upon a set of Bezier curves, located along the circumference of the upper and lower bases of the truncated cone. The mathematical description, elaborated in the course of the research, was used for the computer program LastikTube, which was developed to create 3D macro-models of ribbed tubular garments.

scholarly journals CREATION OF A THREE-DIMENSIONAL MODEL OF ARCHITECTURAL STRUCTURE IN AGISOFT PHOTOSCAN

2020 ◽  
Vol 6 (1) ◽  
pp. 161-166
Author(s):  
Egor V. Kazharin
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
Digital Camera ◽  
Object Model ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Architectural Structures ◽  
Three Dimensional Models ◽  
Time Required ◽  
The Cost

All architectural structures are a subject to periodic surveys and use of photogrammetric methods for these purposes will ensure a reduction in time required to complete the work, required accuracy, as well as ability to fulfill the required measurements on a pair of images in office conditions without additional field visits, which will significantly reduce the cost of implementation of this type of work. In order to solve the problems of building three-dimensional models of such objects, a ground-based photography is used more often. This method of photographing, in comparison with other methods, such as ground-based laser scanning, facade shooting with the help of electronic total stations, seems more affordable, since it does not require the use of expensive equipment, but it makes it possible to build an object model with the specified accuracy. For ground photography it is enough to have a calibrated digital camera, computer and software. The purpose of this work is to study the method of constructing a three-dimensional model of an architectural structure based on photogrammetric processing of images, as well as optimizing the result and demonstrating the operability of the method.

scholarly journals 3D Modelling in solution of cadastral and geodetic tasks

2020 ◽  
Vol 164 ◽  
pp. 07014
Author(s):  
Polina Demidova ◽  
Olga Kolesnik ◽  
Hasan Al Fatin
Keyword(s):  
Russian Federation ◽  
Three Dimensional ◽  
Legal Regulation ◽  
Google Earth ◽  
3D Modelling ◽  
Water Levels ◽  
Data Set ◽  
3D Cadastre ◽  
Dimensional Models ◽  
Three Dimensional Models

The main purpose of this study is demonstrating possibilities of using 3D modelling in solving scientific and practical problems et the field of geodesy and cadastre. Increasing number of publications on this topic among Russian and foreign authors are shown. The article considers examples of creating three-dimensional models for the purposes of cadastre and geodesy. A 3D model of cadastral registration of a complex object (gas station) in the specialized software ArchiCad together with Google Earth is presented. The composition of each stage and data set of each “step” of cadastral works in relation to such objects in Russian Federation are proposed. The article considers shortcomings of legal regulation in relation to 3D cadastre at the present stage. In addition, three-dimensional models of the Dukan reservoir (Iraq), showing water levels at different times, were modelled. They based on digital data obtained from the digitized contour map. And it were used such software products like GlobalMapper, ArcMap and ArcScene. After analyzing the regulatory sources, conclusions about the lack of legal regulation in relation to the 3D cadastre in the Russian Federation were made.

Analysis of human body surface shape using parametric design method

2015 ◽  
Vol 27 (3) ◽  
pp. 434-446 ◽  
Author(s):  
Sungmin Kim
Keyword(s):  
Body Surface ◽  
Parametric Design ◽  
Design Method ◽  
Three Dimensional ◽  
Complex Surface ◽  
Surface Shape ◽  
Body Scan ◽  
Content Type ◽  
Scan Data ◽  
Time Required

Purpose – The purpose of this paper is to analyze automation of body surface shape. Design/methodology/approach – Numerous body landmarks are detected automatically. Body surface can be subdivided into multiple patches in a consistent manner using parametric design method. Findings – Complex surface shape of various human bodies can be analyzed easily and consistently. Research limitations/implications – The proposed method may not be applicable for a body with the shape which significantly differs from that of an average body. Practical implications – This method can greatly reduce the time required to analyze the surface shape of a three dimensional body scan data. Originality/value – The analysis of body surface shape is one of the most important processes especially in designing close fitting garments. The parametric design of body surface patches will facilitate the analysis of numerous body scan data.

scholarly journals TOWARDS THE ENHANCEMENT OF "MINOR" ARCHAEOLOGICAL HERITAGE

2017 ◽  
Vol XLII-2/W3 ◽  
pp. 503-509 ◽  
Author(s):  
S. Morandi ◽  
M. Tremari ◽  
A. Mandelli
Keyword(s):  
Hydroelectric Plant ◽  
Three Dimensional ◽  
3D Modelling ◽  
Archaeological Sites ◽  
Archaeological Excavation ◽  
Archaeological Heritage ◽  
Heritage Sites ◽  
3D Data ◽  
Modelling Techniques ◽  
Three Dimensional Models

The research is an analysis of the recording, reconstruction and visualisation of the 3D data of a XVIII century watermill, identified in an emergency archaeological excavation during the construction of the mini-hydroelectric plant on the bank of the Adda river in the municipality of Pizzighettone (Cremona, Lombardy, Italy). <br><br> The work examines the use and the potentials of modern digital 3D modelling techniques applied to archaeological heritage aimed to increase the research, maintenance and presentation with interactive products. The use of three-dimensional models managed through AR (Augmented Reality) and VR (Virtual Reality) technologies with mobile devices gives several opportunities in the field of study and communication. It also improves on-site exploration of the landscape, enhancing the “minor” archaeological sites, daily subjected to numerous emergency works and facilitating the understanding of heritage sites.

Three-Dimensional Reconstruction of Native Androctonus Australis Hemocyanin

1990 ◽  
Vol 48 (1) ◽  
pp. 452-453
Author(s):  
Nicolas Boisset ◽  
Jean-Christophe Taveau ◽  
Jean Lamy ◽  
Terence Wagenknecht ◽  
Michael Radermacher ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Solid Body ◽  
Body Surface ◽  
Three Dimensional ◽  
Staining Technique ◽  
Three Dimensional Reconstruction ◽  
Dimensional Reconstruction ◽  
View Reconstruction ◽  
Surface Representations ◽  
Top View

Hemocyanin, the respiratory pigment of the scorpion Androctonus australis is composed of 24 kidney shaped subunits. A model of architecture supported by many indirect arguments has been deduced from electron microscopy (EM) and immuno-EM. To ascertain, the disposition of the subunits within the oligomer, the 24mer was submitted to three-dimensional reconstruction by the method of single-exposure random-conical tilt series.A sample of native hemocyanin, prepared with the double layer negative staining technique, was observed by transmisson electron microscopy under low-dose conditions. Six 3D-reconstructions were carried out indenpendently from top, side and 45°views. The results are composed of solid-body surface representations, and slices extracted from the reconstruction volume.The main two characters of the molecule previously reported by Van Heel and Frank, were constantly found in the solid-body surface representations. These features are the presence of two different faces called flip and flop and a rocking of the molecule around an axis passing through diagonnally opposed hexamers. Furthermore, in the solid-body surface of the top view reconstruction, the positions and orientations of the bridges connecting the half molecules were found in excellent agreement with those predicted by the model.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

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