Three-Dimensional Representation of Curved Nanostructures

2004 ◽  
Vol 820 ◽  
Author(s):  
Z. Huang ◽  
D.A. Dikin ◽  
W. Ding ◽  
Y. Qiao ◽  
Y. Fridman ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Accurate Estimate ◽  
One Dimensional ◽  
3D Space ◽  
Precise Knowledge ◽  
Three Dimensional Representation ◽  
Resonance Data ◽  
Image Pairs ◽  
Program Error ◽  
Boron Nanowires

AbstractNanostructures, such as nanowires, nanotubes, and nanocoils, can be described in many cases as quasi one-dimensional (1D) curved objects projecting in three-dimensional (3D) space. A parallax method to reconstruct the correct three-dimensional geometry of such 1D nanostructures is presented. A series of images were acquired at different view angles, and from those image pairs, 3D representations were constructed using a MATLAB program. Error analysis as a function of view-angle between the two images is discussed. As an example application, we demonstrate the importance of knowing the true 3D shape of Boron nanowires. Without precise knowledge of the nanowire's dimensions, diameter and length, mechanical resonance data cannot be properly fit to obtain an accurate estimate of the Young's modulus.

A CAD/CAM Representation Model Applied to Tolerance Transfer Methods

1998 ◽  
Author(s):  
Alain Desrochers
Keyword(s):  
Three Dimensional ◽  
Dimensional Representation ◽  
One Dimensional ◽  
Dimensional Tolerance ◽  
Representation Model ◽  
Three Dimensional Representation ◽  
Tolerance Chart ◽  
Cad Cam ◽  
Tolerance Charts

Abstract This paper presents the adaptation of tolerance transfer techniques to a model called TTRS for Technologically and Topologically Related Surfaces. According to this model, any three-dimensional part can be represented as a succession of surface associations forming a tree. Additional tolerancing information can be associated to each TTRS represented as a node on the tree. This information includes dimensional tolerances as well as tolerance chart values. Rules are then established to simulate tolerance chains or stack up along with tolerance charts directly from the graph. This way it becomes possible to combine traditional one dimensional tolerance transfer techniques with a powerful three-dimensional representation model providing high technological contents.

scholarly journals Computational Design and Analysis of a Magic Snake

2020 ◽  
Vol 12 (5) ◽  
Author(s):  
Zilong Li ◽  
Songming Hou ◽  
Thomas C. Bishop
Keyword(s):  
3D Structure ◽  
Three Dimensional ◽  
Computational Design ◽  
Space Curve ◽  
One Dimensional ◽  
3D Structures ◽  
Multi Scale ◽  
3D Space ◽  
Slender Bodies ◽  
Self Similar

Abstract The Magic Snake (Rubik’s Snake) is a toy that was invented decades ago. It draws much less attention than Rubik’s Cube, which was invented by the same professor, Erno Rubik. The number of configurations of a Magic Snake, determined by the number of discrete rotations about the elementary wedges in a typical snake, is far less than the possible configurations of a typical cube. However, a cube has only a single three-dimensional (3D) structure while the number of sterically allowed 3D conformations of the snake is unknown. Here, we demonstrate how to represent a Magic Snake as a one-dimensional (1D) sequence that can be converted into a 3D structure. We then provide two strategies for designing Magic Snakes to have specified 3D structures. The first enables the folding of a Magic Snake onto any 3D space curve. The second introduces the idea of “embedding” to expand an existing Magic Snake into a longer, more complex, self-similar Magic Snake. Collectively, these ideas allow us to rapidly list and then compute all possible 3D conformations of a Magic Snake. They also form the basis for multidimensional, multi-scale representations of chain-like structures and other slender bodies including certain types of robots, polymers, proteins, and DNA.

P-Spice Modeling Three-Dimensional Propagation of Ultrasound Diffraction Considering a Gaussian Beam Approach

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Soucrati Hanane ◽  
Chitnalah Ahmed ◽  
Aouzale Noureddine ◽  
El Idrissi Abdelaziz
Keyword(s):  
Wave Propagation ◽  
Three Dimensional ◽  
Gaussian Beams ◽  
Average Pressure ◽  
Transmission Line Model ◽  
Spice Simulation ◽  
Ultrasonic Wave Propagation ◽  
One Dimensional ◽  
Spice Model ◽  
3D Space

In this paper, we propose a new method for simulating three-dimensional (3D) ultrasonic wave propagation using P-Spice like simulator. We use a one-dimensional transmission line model to implement the diffraction losses. In order to simulate the beam pattern considering axial and radial orientations, we calculate the diffraction losses in 3D space. First, we express the radiated field using a set of Gaussian beams. Calculating the average pressure over the receiver surface allows us to determine the diffraction losses. These losses are then incorporated into the P-Spice model via the G parameter which is axial and radial orientations dependent. Comparison between P-Spice simulation and analytical model results shows good agreements.

A CAD/CAM Representation Model Applied to Tolerance Transfer Methods

2003 ◽  
Vol 125 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Alain Desrochers
Keyword(s):  
Three Dimensional ◽  
Dimensional Representation ◽  
One Dimensional ◽  
Dimensional Tolerance ◽  
Representation Model ◽  
Three Dimensional Representation ◽  
Tolerance Chart ◽  
Cad Cam ◽  
Tolerance Charts

This paper presents the adaptation of tolerance transfer techniques to a model called TTRS for Technologically and Topologically Related Surfaces. According to this model, any three-dimensional part can be represented as a succession of surface associations forming a tree. Additional tolerancing information can be associated to each surface association represented as a node on the tree. This information includes dimensional tolerances as well as tolerance chart values. Rules are then established to infer tolerance chains or stack up along with tolerance charts directly from the graph. This way it becomes possible to combine traditional one dimensional tolerance transfer techniques with a powerful three-dimensional representation model providing high technological contents.

ON THE "CROSSROAD AREA–SADDLE AREA" AND "CROSSROAD AREA–SPRING AREA" TRANSITIONS

1991 ◽  
Vol 01 (03) ◽  
pp. 641-655 ◽  
Author(s):  
C. MIRA ◽  
J. P. CARCASSÈS
Keyword(s):  
Three Dimensional ◽  
Parameter Plane ◽  
Flip Bifurcation ◽  
Two Dimensional ◽  
Cusp Point ◽  
Dimensional Representation ◽  
One Dimensional ◽  
Transition Mechanism ◽  
Three Dimensional Representation ◽  
Spring Area

Let T be a one-dimensional or two-dimensional map. The three considered areas are related to three different configurations of fold and flip bifurcation curves, centred at a cusp point of a fold curve in the T parameter plane (b, c). The two transitions studied here occur via a codimension-three bifurcation defined in each case, when varying a third parameter a. The transition "mechanism," from an area type to another one, is given with a three-dimensional representation describing the sheet configuration of the parameter plane.

Structure and function of neural networks in the retina

1988 ◽  
Vol 46 ◽  
pp. 26-27
Author(s):  
Peter Sterling
Keyword(s):  
Ganglion Cells ◽  
Three Dimensional ◽  
Structure And Function ◽  
Synaptic Connections ◽  
Visual Axis ◽  
One Dimensional ◽  
Cat Retina ◽  
Ultrathin Sections ◽  
And Function ◽  
Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

Revealing gross three-dimensional structure in the SEM

1987 ◽  
Vol 45 ◽  
pp. 656-657
Author(s):  
Sterling P. Newberry
Keyword(s):  
Freeze Drying ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Small Object ◽  
Final Solution ◽  
Dimensional Representation ◽  
X Ray ◽  
Three Dimensional Representation ◽  
Freeze Dried ◽  
Critical Point Drying

The beautiful three dimensional representation of small object surfaces by the SEM leads one to search for ways to open up the sample and look inside. Could this be the answer to a better microscopy for gross biological 3-D structure? We know from X-Ray microscope images that Freeze Drying and Critical Point Drying give promise of adequately preserving gross structure. Can we slice such preparations open for SEM inspection? In general these preparations crush more readily than they slice. Russell and Dagihlian got around the problem by “deembedding” a section before imaging. This some what defeats the advantages of direct dry preparation, thus we are reluctant to accept it as the final solution to our problem. Alternatively, consider fig 1 wherein a freeze dried onion root has a window cut in its surface by a micromanipulator during observation in the SEM.

Exploring the Multidimensional Facets of Authoritarianism: Authoritarian Aggression and Social Dominance Orientation

2008 ◽  
Vol 67 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Stefano Passini
Keyword(s):  
Social Dominance ◽  
Factor Model ◽  
Three Dimensional ◽  
Social Dominance Orientation ◽  
Model Fit ◽  
Regression Analyses ◽  
One Dimensional ◽  
Confirmatory Factor ◽  
The One ◽  
Better Than

The relation between authoritarianism and social dominance orientation was analyzed, with authoritarianism measured using a three-dimensional scale. The implicit multidimensional structure (authoritarian submission, conventionalism, authoritarian aggression) of Altemeyer’s (1981, 1988) conceptualization of authoritarianism is inconsistent with its one-dimensional methodological operationalization. The dimensionality of authoritarianism was investigated using confirmatory factor analysis in a sample of 713 university students. As hypothesized, the three-factor model fit the data significantly better than the one-factor model. Regression analyses revealed that only authoritarian aggression was related to social dominance orientation. That is, only intolerance of deviance was related to high social dominance, whereas submissiveness was not.

Three-dimensional Reconstruction of Microscopic Image Based on Multi-ST Algorithm

2020 ◽  
Vol 64 (2) ◽  
pp. 20506-1-20506-7
Author(s):  
Min Zhu ◽  
Rongfu Zhang ◽  
Pei Ma ◽  
Xuedian Zhang ◽  
Qi Guo
Keyword(s):  
3D Reconstruction ◽  
Three Dimensional ◽  
Scale Model ◽  
Microscopic Image ◽  
Multi Scale ◽  
Gaussian Pyramid ◽  
Cost Aggregation ◽  
Dimensional Reconstruction ◽  
Image Pairs ◽  
Accurate Matching

Abstract Three-dimensional (3D) reconstruction is extensively used in microscopic applications. Reducing excessive error points and achieving accurate matching of weak texture regions have been the classical challenges for 3D microscopic vision. A Multi-ST algorithm was proposed to improve matching accuracy. The process is performed in two main stages: scaled microscopic images and regularized cost aggregation. First, microscopic image pairs with different scales were extracted according to the Gaussian pyramid criterion. Second, a novel cost aggregation approach based on the regularized multi-scale model was implemented into all scales to obtain the final cost. To evaluate the performances of the proposed Multi-ST algorithm and compare different algorithms, seven groups of images from the Middlebury dataset and four groups of experimental images obtained by a binocular microscopic system were analyzed. Disparity maps and reconstruction maps generated by the proposed approach contained more information and fewer outliers or artifacts. Furthermore, 3D reconstruction of the plug gauges using the Multi-ST algorithm showed that the error was less than 0.025 mm.

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