scholarly journals Computational Design of Planar Multistable Compliant Structures

2021 ◽  
Vol 40 (5) ◽  
pp. 1-16
Author(s):  
Ran Zhang ◽  
Thomas Auzinger ◽  
Bernd Bickel
Keyword(s):  
Graph Theory ◽  
3D Printing ◽  
Elastic Energy ◽  
Computational Design ◽  
Geometric Realization ◽  
Geometric Parameters ◽  
Stable States ◽  
Error Metric ◽  
The Given

This article presents a method for designing planar multistable compliant structures. Given a sequence of desired stable states and the corresponding poses of the structure, we identify the topology and geometric realization of a mechanism—consisting of bars and joints—that is able to physically reproduce the desired multistable behavior. In order to solve this problem efficiently, we build on insights from minimally rigid graph theory to identify simple but effective topologies for the mechanism. We then optimize its geometric parameters, such as joint positions and bar lengths, to obtain correct transitions between the given poses. Simultaneously, we ensure adequate stability of each pose based on an effective approximate error metric related to the elastic energy Hessian of the bars in the mechanism. As demonstrated by our results, we obtain functional multistable mechanisms of manageable complexity that can be fabricated using 3D printing. Further, we evaluated the effectiveness of our method on a large number of examples in the simulation and fabricated several physical prototypes.

Pattern Recognition in Histo-Pathology: Basic Considerations

1982 ◽  
Vol 21 (01) ◽  
pp. 15-22 ◽  
Author(s):  
W. Schlegel ◽  
K. Kayser
Keyword(s):  
Pattern Recognition ◽  
Graph Theory ◽  
Normal Tissue ◽  
Diagnostic Procedures ◽  
Minimal Distance ◽  
Malignant Growth ◽  
Colon Tissue ◽  
First Results ◽  
Tissue Structures ◽  
The Given

A basic concept for the automatic diagnosis of histo-pathological specimen is presented. The algorithm is based on tissue structures of the original organ. Low power magnification was used to inspect the specimens. The form of the given tissue structures, e. g. diameter, distance, shape factor and number of neighbours, is measured. Graph theory is applied by using the center of structures as vertices and the shortest connection of neighbours as edges. The algorithm leads to two independent sets of parameters which can be used for diagnostic procedures. First results with colon tissue show significant differences between normal tissue, benign and malignant growth. Polyps form glands that are twice as wide as normal and carcinomatous tissue. Carcinomas can be separated by the minimal distance of the glands formed. First results of pattern recognition using graph theory are discussed.

An Algorithm for the Enumeration of Serial and/or Parallel Combinations of Kinematic Building Blocks

2004 ◽  
Author(s):  
Hong-Sen Yan ◽  
Feng-Ming Ou ◽  
Ming-Feng Tang
Keyword(s):  
Graph Theory ◽  
Building Blocks ◽  
Power Source ◽  
Cam Follower ◽  
Tree Representations ◽  
The Given

An algorithm is presented, based on graph theory, for enumerating all feasible serial and/or parallel combined mechanisms from the given rotary or translational power source and specific kinematic building blocks. Through the labeled out-tree representations for the configurations of combined mechanisms, the enumeration procedure is developed by adapting the algorithm for the enumeration of trees. A rotary power source and four kinematic building blocks: a crank-rocker linkage, a rack-pinion, a double-slider mechanism, and a cam-follower mechanism, are chosen as the combination to illustrate the algorithm. And, two examples are provided to validate the algorithm.

scholarly journals Graph Theoretic Techniques in the Analysis of Uniquely Localizable Sensor Networks

2009 ◽  
pp. 146-173 ◽  
Author(s):  
Bill Jackson ◽  
Tibor Jordán
Keyword(s):  
Graph Theory ◽  
Sensor Networks ◽  
Optimization Problems ◽  
Partial Information ◽  
Two Dimensions ◽  
Localization Problem ◽  
Graph Theoretic ◽  
Network Localization ◽  
Exact Location ◽  
The Given

In the network localization problem the goal is to determine the location of all nodes by using only partial information on the pairwise distances (and by computing the exact location of some nodes, called anchors). The network is said to be uniquely localizable if there is a unique set of locations consistent with the given data. Recent results from graph theory and combinatorial rigidity made it possible to characterize uniquely localizable networks in two dimensions. Based on these developments, extensions, related optimization problems, algorithms, and constructions also became tractable. This chapter gives a detailed survey of these new results from the graph theorist’s viewpoint.

scholarly journals Cryptosystem using double vertex graph

2020 ◽  
Vol 13 (44) ◽  
pp. 4483-4489
Author(s):  
C Beaula ◽  
Keyword(s):  
Graph Theory ◽  
Secure Communication ◽  
System Method ◽  
Encryption And Decryption ◽  
Vertex Graph ◽  
Private And Public ◽  
Almost All ◽  
Encryption Method ◽  
The Given ◽  
Edge Labeling

Background/Objective: The Coronavirus Covid-19 has affected almost all the countries and millions of people got infected and more deaths have been reported everywhere. The uncertainty and fear created by the pandemic can be used by hackers to steal the data from both private and public systems. Hence, there is an urgent need to improve the security of the systems. This can be done only by building a strong cryptosystem. So many researchers started embedding different topics of mathematics like algebra, number theory, and so on in cryptography to keep the system, safe and secure. In this study, a cryptosystem using graph theory has been attempted, to strengthen the security of the system. Method: A new graph is constructed from the given graph, known as a double vertex graph. The edge labeling of this double vertex graph is used in encryption and decryption. Findings: A new cryptosystem using the amalgamation of the path, its double vertex graph and edge labeling has been proposed. From the double vertex graph of a path, we have given a method to find the original path. To hack such an encrypted key, the knowledge of graph theory is important, which makes the system stronger. Applications:The one-word encryption method will be useful in every security system that needs a password for secure communication or storage or authentication. Keywords: Double vertex graphs; path; adjacency matrix; encryption; cryptography

Catastrophe Theory Analysis of Rock Mass Dynamic Destabilization

2012 ◽  
Vol 166-169 ◽  
pp. 2774-2781
Author(s):  
Yong Zhang ◽  
Da Jian Hu ◽  
Lu Xue
Keyword(s):  
Rock Mass ◽  
Elastic Energy ◽  
Quantitative Description ◽  
Scientific Basis ◽  
Rock System ◽  
Catastrophe Model ◽  
Rock Stability ◽  
Before And After ◽  
The Given ◽  
First Time

In step with body Ⅱ, analytic solution and illustration of elastic energy releasing amount of rock mass dynamic destabilization are given for the first time in the form of precise and approximate catastrophe model. It is upgraded from qualitative understand to quantitative description that study on rock stability at the stage before and after earthquake and rockburst. The halting point’s position of rock mass dynamic destabilization is ascertained strictly, and it offers scientific basis for the calculation on earthquake efficiency, the study on earthquake energy magnitude released, earthquake stress drop, fault offset after earthquake and amount of elastic strain recovery of surrounding rock. The system possesses the capability of applying work to surroundings when it destabilizes, and earthquake wave energy is the work that destabilizing rock system applies to surroundings by way of destructive. The given illustration of elastic energy releasing amount implicates wealth of information, it produces credible evidence for confirming that the mathematical abstract of rock dynamic destabilization is fold catastrophe model.

scholarly journals Bone-inspired 3D printed structures for construction applications

2019 ◽  
Vol 14 (1) ◽  
pp. 111-124
Author(s):  
Roberto Naboni ◽  
Anja Kunic
Keyword(s):  
Additive Manufacturing ◽  
3D Printing ◽  
Computational Design ◽  
Bone Microstructure ◽  
Manufacturing Technology ◽  
Support Design ◽  
Efficient Construction ◽  
3D Printed ◽  
Viable Approach ◽  
Tectonic System

Overconsumption of resources is one of the greatest challenges of our century. The amount of material that is being extracted, harvested and consumed in the last decades is increasing tremendously. Building with new manufacturing technology, such as 3D Printing, is offering new perspectives in the way material is utilized sustainably within a construction. This paper describes a study on how to use Additive Manufacturing to support design logics inspired by the bone microstructure, in order to build materially efficient architecture. A process which entangles computational design methods, testing of 3D printed specimens, developments of prototypes is described. A cellular-based tectonic system with the capacity to vary and adapt to different loading conditions is presented as a viable approach to a material-efficient construction with Additive Manufacturing.

scholarly journals Sun Toughness Conditions for P 2 and P 3 Factor Uniform and Factor Critical Avoidable Graphs

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Shu Gong ◽  
Haci Mehmet Baskonus ◽  
Wei Gao
Keyword(s):  
Graph Theory ◽  
Computer Networks ◽  
The Sun ◽  
Graph Structure ◽  
Network Graph ◽  
The Given ◽  
Path Factor

The security of a network is closely related to the structure of the network graph. The denser the network graph structure is, the better it can resist attacks. Toughness and isolated toughness are used to characterize the vulnerable programs of the network which have been paid attention from mathematics and computer scholars. On this basis, considering the particularity of the sun component structures, sun toughness was introduced in mathematics and applied to computer networks. From the perspective of modern graph theory, this paper presents the sun toughness conditions of the path factor uniform graph and the path factor critical avoidable graph in P ≥ 2 -factor and P ≥ 3 -factor settings. Furthermore, examples show that the given boundaries are sharp.

scholarly journals Mechanical Testing of Poly Hydroxy Butyrate Co Valerate and Natural Fiber by Varying Fiber Length

2020 ◽  
Vol 8 (4S4) ◽  
pp. 200-203
Keyword(s):  
3D Printing ◽  
Natural Fiber ◽  
Volume Fraction ◽  
Composite Plates ◽  
Weight Percentage ◽  
Practical Applications ◽  
Printing Technique ◽  
Critical Issues ◽  
The Given ◽  
3D Printing Technique

The knowledge of 3D printing material used in 3D printing technique is so abundant. Even though there are many critical issues in practical applications. This paper reports the mechanical properties of Environmental friendly Bio composites. This composite material is intended to be used as a replacement for the current 3D printing material. The composite was prepared in compression molding technique under 150 kg/cm2 pressure. The composite consists of Poly Hydroxy Butyrate co Valerate (PHBV) and Sansevieria Roxburghiana. The tensile strength of the given specimen is found to be increased by the change in the volume fraction of fibers. Initially composite plates composed of both PHBV and Sansevieria Roxburghiana are prepared with different weight percentage of PHBV and different lengths of fiber such as 20mm, 30mm, 40mm and 50mm.

Impact of Geometric Features on Color Similarity Perception of Displayed 3D Tablets

2020 ◽  
Vol 64 (5) ◽  
pp. 50404-1-50404-12
Author(s):  
Jiangping Yuan ◽  
Hua Li ◽  
Baohui Xu ◽  
Guangxue Chen
Keyword(s):  
3D Printing ◽  
Three Dimensional ◽  
Color Difference ◽  
Geometric Features ◽  
Shape Features ◽  
Color Similarity ◽  
Bright Green ◽  
Similarity Scaling ◽  
The Given ◽  
Printing Techniques

Abstract To explore the effects of geometric features on the color similarity perception of displayed three-dimensional (3D) tablets designed by color 3D modeling techniques or printed by color 3D printing techniques, two subjective similarity scaling tasks were conducted for color tablets with four shape features (circular, oval, triangular-columnar, and rounded-cuboid shapes) and four notch features (straight V, straight U, crisscross V, and crisscross U shapes) displayed on a calibrated monitor using the nine-level category judgement method. Invited observers were asked to assort all displayed samples into tablet groups using six surface colors (aqua blue, bright green, pink, orange yellow, bright red, and silvery white), and all perceived similarity values were recorded and compared to original samples successively. The results showed that the similarity perception of tested tablets was inapparently affected by the given shape features and notch features, and it should be judged by a flexible interval rather than by a fixed color difference. This research provides practical insight into the visualization of color similarity perception for displayed personalized tablets to advance precision medicine by 3D printing.

Digital grotesque: Towards a micro-tectonic architecture

2013 ◽  
Vol 5 (2) ◽  
pp. 194-201
Author(s):  
Michael Hansmeyer ◽  
Benjamin Dillenburger
Keyword(s):  
Additive Manufacturing ◽  
3D Printing ◽  
Large Scale ◽  
New Technologies ◽  
Computational Design ◽  
Small Scale ◽  
Printing Technology ◽  
Recent Developments ◽  
Complex Forms ◽  
Specific Experiment

Computational design allows for architecture with an extraordinary degree of topographical and topological complexity. Limitations of traditional CNC technologies have until recently precluded this architecture from being fabricated. While additive manufacturing has made it possible to materialize these complex forms, this has occurred only at a very small scale. In trying to apply additive manufacturing to the construction of full-scale architecture, one encounters a dilemma: existing large-scale 3D printing methods can only print highly simplified shapes with rough details, while existing high-resolution technologies have limited print spaces, high costs, or material attributes that preclude a structural use. This paper provides a brief background on additive manufacturing technology and presents recent developments in sand-printing technology that overcome current 3D printing restrictions. It then presents a specific experiment, Digital Grotesque project, which is the first application of 3D sand-printing technology at an architecture scale. It describes how this project attempts to exploit the potentials of these new technologies.

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