Determination of Drying Times for Irregular Two and Three-Dimensional Objects

2003 ◽  
Vol 125 (6) ◽  
pp. 1190-1193 ◽  
Author(s):  
A. Z. Sahin and ◽  
I. Dincer
Keyword(s):  
Experimental Data ◽  
Analytical Model ◽  
Three Dimensional ◽  
Elliptic Cylinder ◽  
Drying Time ◽  
Shape Factors ◽  
High Agreement ◽  
Three Dimensional Objects ◽  
Infinite Slab

This paper deals with development of a new analytical model for determining the drying times of irregular-shaped multi-dimensional objects. Geometrically irregular two and three-dimensional products are approximated by elliptical cylinder and ellipsoidal shapes, respectively. Using experimental drying parameters that are available from the literature, drying times of irregular, multi-dimensional products are determined through the present models. Geometric shape factors for the elliptic cylinder and ellipsoid are employed and based on the reference drying time for an infinite slab. In addition, the present models are verified through comparison with experimental drying times of several food products. The accuracy of the predictions using the present models is then discussed, and a considerably high agreement is obtained between the predictions and experimental data.

Simultaneous Determination of Steady Temperatures and Heat Fluxes on Surfaces of Three Dimensional Objects Using FEM

2001 ◽  
Author(s):  
Brian H. Dennis ◽  
George S. Dulikravich
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Heat Conduction ◽  
Three Dimensional ◽  
Heat Fluxes ◽  
Multiply Connected ◽  
Three Dimensional Objects ◽  
Solid Objects ◽  
System Solution

Abstract A finite element method (FEM) formulation is presented for the prediction of unknown steady boundary conditions in heat conduction on multiply connected three-dimensional solid objects. The present FEM formulation is capable of determining temperatures and heat fluxes on the boundaries where such quantities are unknown or inaccessible, provided such quantities are sufficiently over-specified on other boundaries. Details of the discretization, linear system solution techniques, regularization, and sample results for 3-D problems are presented.

scholarly journals Simulation Informed CAD for 3D Nanoprinting

Micromachines ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 8 ◽  
Author(s):  
Jason D. Fowlkes ◽  
Robert Winkler ◽  
Eva Mutunga ◽  
Philip D. Rack ◽  
Harald Plank
Keyword(s):  
Analytical Model ◽  
Computer Aided Design ◽  
Critical Mass ◽  
Three Dimensional ◽  
Three Dimensional Objects ◽  
Non Linear ◽  
Out Of Plane ◽  
Digital Scanning ◽  
Definition Of ◽  
Bending Nanowires

A promising 3D nanoprinting method, used to deposit nanoscale mesh style objects, is prone to non-linear distortions which limits the complexity and variety of deposit geometries. The method, focused electron beam-induced deposition (FEBID), uses a nanoscale electron probe for continuous dissociation of surface adsorbed precursor molecules which drives highly localized deposition. Three dimensional objects are deposited using a 2D digital scanning pattern—the digital beam speed controls deposition into the third, or out-of-plane dimension. Multiple computer-aided design (CAD) programs exist for FEBID mesh object definition but rely on the definition of nodes and interconnecting linear nanowires. Thus, a method is needed to prevent non-linear/bending nanowires for accurate geometric synthesis. An analytical model is derived based on simulation results, calibrated using real experiments, to ensure linear nanowire deposition to compensate for implicit beam heating that takes place during FEBID. The model subsequently compensates and informs the exposure file containing the pixel-by-pixel scanning instructions, ensuring nanowire linearity by appropriately adjusting the patterning beam speeds. The derivation of the model is presented, based on a critical mass balance revealed by simulations and the strategy used to integrate the physics-based analytical model into an existing 3D nanoprinting CAD program is overviewed.

scholarly journals КОМП’ЮТЕРНА ТЕХНОЛОГІЯ АНАЛІЗУ ТА ДИЗАЙНУ ПРЕДМЕТНОГО СЕРЕДОВИЩА З ПОЗИЦІЇ ВІЗУАЛЬНОГО СПРИЙНЯТТЯ

2020 ◽  
pp. 39-48
Author(s):  
Т. В. Булгакова ◽  
О. В. Полякова ◽  
С. С. Кисіль ◽  
О. Є. Шмельова
Keyword(s):  
Visual Perception ◽  
Quantitative Determination ◽  
Three Dimensional ◽  
Geometrical Model ◽  
Human Being ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Three Dimensional Objects ◽  
Computer Technologies

The purpose of the investigation is the development of computer technology of analysis and design of built environment from the point of its visual perception in the space of its three-dimensional model without using the perspective projections. The methodology were used to achieve the purpose: analysis of the scientific publications on the topic of object environment composition; applied geometry methods, method of division of the geometrical object into simplexes (triangulation), methods of advanced algebra and analytical geometry; computer modeling for construction of the model of visual perception of the environment. Methods of analysis of the three-dimensional model on the basis of modeling of visual perception by means of computer technologies directly in the area of the model without using perspective projections are developed. It is offered to analyze the visual perception of any objects and their relations by means of using the solid angles with the vertices placed in the point of view and the surfaces that surround the visible contours of three-dimensional objects. This approach gives the opportunity to analyze the objects simultaneously regardless their position according to the observer; apart of that, the objects, which are accepted similarly in the reality, will have the same geometrical features during the modeling of visual perception and beside that, the refusal of using of the perspective projections will make possible to avoid the distortion of the images. The algorithm of determination of the solid angles to three-dimensional objects, which is the basis of computer methods of compositional analysis of the object environment from the position of visual perception without the use of perspective projections, is developed. The geometrical model of visual perception by a human being from the certain point of perception is built. It makes possible to define correctly visual features of the object environment and gives the opportunity to analyze the whole surrounding of the observer in the area of 360 degrees. Scientific novelty of the investigation means that the methods of analysis of the three-dimensional model on the basis of modeling of visual perception by means of computer technologies directly in the area of the model without using perspective projections are developed for the first time. The concept of the geometrical model of visual perception by a human being from the certain point of perception is developed. The further development of the methodology of quantitative determination of characteristics of object environment by means of computer technologies is defined. Practical significance shows that the results of the scientific investigation can be used for analysis and judgments of the aesthetic peculiarities of the object environment by means of computer technologies with quantitative determination of characteristics of object environment from the point of its visual perception. Such approach gives the opportunity to develop and create the further certain recommendations and instructions for correction of the existing environment and for the development of the new one.

Synthesis of Three-Dimensional Models from Drawings Based on Spectral Graph Theory

2015 ◽  
Vol 756 ◽  
pp. 598-603 ◽  
Author(s):  
Aleksey Zakharov ◽  
Arkady Zhiznyakov
Keyword(s):  
Graph Theory ◽  
Three Dimensional ◽  
Spectral Graph Theory ◽  
Boundary Representation ◽  
Three Dimensional Model ◽  
Three Dimensional Objects ◽  
Spectral Graph ◽  
Dimensional Models ◽  
Three Dimensional Models

Task of automatic reconstruction of three-dimensional objects by drawing views presented. The algorithm based on a boundary representation of three-dimensional models. The algorithm consists of the following steps: automatic separation of the drawing per the views, determination of three-dimensional coordinates of vertices, definition and marking of wire model primitives, reconstruction of model faces and model elements. The fundamental concept of the algorithm is to find the structural elements of three-dimensional model with usage of pre-specified patterns. The templates are described by means of matrices. Matching algorithm uses spectral graph theory. Reconstruction results are presented.

scholarly journals Creation of Geodistributed SCADA-System

2019 ◽  
Author(s):  
Петр Кабанов ◽  
Peter Kabanov ◽  
Михаил Суходоев ◽  
Mikhail Sukhodoev
Keyword(s):  
Software Development ◽  
Three Dimensional ◽  
Spatial Transformation ◽  
Three Dimensional Objects ◽  
Scada System ◽  
Scada Systems ◽  
Full Power ◽  
Gis System

This article shows the possibility of combining modern software development technologies. SCADA systems usually do not use the full power of modern visualization technologies (rendering of three-dimensional objects, spatial transformation, etc.). In addition to graphics, users of these systems have a question about the possibility of using GIS systems to facilitate the determination of the location of objects (on global, local, and other maps). Using all the technologies described in this article, a system was developed that meets the basic requirements of the SCADA system. The developed system perfectly combines three-dimensional visualization and support of the GIS system. These implementations showed excellent results and feedback from users (with the test and final versions of the program).

The structure of haemoglobin VIII. A three-dimensional Fourier synthesis at 5.5 Å resolution: determination of the phase angles

1961 ◽  
Vol 265 (1320) ◽  
pp. 15-38 ◽  
Keyword(s):  
Phase Angle ◽  
Least Squares Method ◽  
Heavy Atom ◽  
Three Dimensional ◽  
Protein Molecule ◽  
Fourier Synthesis ◽  
Shape Factors ◽  
Heavy Atoms ◽  
Phase Angles

Determination of the phase angles of a crystalline protein requires a series of isomorphous heavy-atom compounds, with heavy atoms attached to different sites on the protein molecule. The asymmetric unit of horse oxyhaem oglobin was found to combine with heavy atoms at two different sites which are now known to be sulphydryl groups. Altogether six different heavy - atom com pounds of haemoglobin were made which proved isomorphous on X -ray analysis. The positions of the heavy atoms were determined first by difference Patterson and Fourier projections on the centrosym metric plane of the monoclinic crystals, and later by three-dimensional correlation functions, ( F H 1 — F H 2 ) 2 being used as coefficients, where F H 1 and F H 2 are the structure factors of the two different heavy-atom compounds. The parameters and anisotropic shape factors of the heavy atoms were refined by a three-dimensional least-squares method. For each of the 1200 reflexions in the limiting sphere of (5.5 Å) -1 the structure amplitudes of all seven compounds were combined in an Argand diagram and the probability of the phase angle having a value a was calculated for oc = 0, 5, 10, ..., 355°. The coefficients for the final Fourier summation were then calculated in two different ways. In one method the vector from the origin to the centroid of the probability distribution, plotted around a circle of radius | F |, was chosen as the ‘best F’. The alternative set of coefficients was calculated, using the full, observed, value of F and the most probable value of the phase angle a. The most probable error in phase angle was found to be 23°, and the standard error in electron density to be expected in the final results 0.12 e/Å 3 .

Determination of the Duration of Memory for Viscoelastic Materials

1970 ◽  
Vol 37 (2) ◽  
pp. 449-453 ◽  
Author(s):  
M. H. Gradowczyk ◽  
J. Soussou ◽  
F. Moavenzadeh
Keyword(s):  
Experimental Data ◽  
Anisotropic Material ◽  
Finite Interval ◽  
Computing Time ◽  
Three Dimensional ◽  
Viscoelastic Materials ◽  
One Dimensional

The possibility of limiting the memory of nonlinear nonaging viscoelastic materials is discussed. If the deformation histories are bounded, then the memory interval −∞ < τ ≤ t can be reduced to the finite interval t −d ≤ τ, where d ≥ 0 is the duration of memory. It is shown how the duration in relaxation and creep can be obtained for one-dimensional motions. As an application the duration of memory in relaxation and creep of solid polyurethane is computed from available experimental data. It is also shown that when the functionals are evaluated numerically, the use of the duration reduces significantly the computing time. The case of anisotropic material in three-dimensional motions is also discussed.

Three-Dimensional Cartesian Grid Method for the Simulations of Flows with Shock Waves in the Domains with Varying Boundaries

2020 ◽  
pp. 2050046
Author(s):  
V. V. Elesin ◽  
D. A. Sidorenko ◽  
P. S. Utkin
Keyword(s):  
Experimental Data ◽  
Shock Wave ◽  
Wave Propagation ◽  
Three Dimensional ◽  
Grid Method ◽  
Cartesian Grid ◽  
Computational Cell ◽  
Cartesian Grid Method ◽  
Moving Particle

This paper is devoted to the development and quantitative evaluation of the properties of the numerical algorithm of the Cartesian grid method for three-dimensional (3D) simulation of shock-wave propagation in areas of varying shape. The detailed description of the algorithm is presented. The algorithm is relatively simple to implement and does not require solving the problem of determination of the shape of the body’s boundary intersection with regular computational cell. The accuracy of the algorithm is demonstrated by comparing the simulated and experimental data in the problems of the interaction of a shock wave (SW) with a nonmoving sphere and a moving particle.

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

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