Eliminating Boundary Nodes in Substructuring of Large Structures

2014 ◽  
Author(s):  
Omid Kazemi ◽  
Parviz E. Nikravesh
Keyword(s):  
Model Reduction ◽  
Degrees Of Freedom ◽  
Simple Structure ◽  
Reduced Model ◽  
Original Structure ◽  
Large Structure ◽  
Component Structure ◽  
Large Structures ◽  
Two Component ◽  
Substructuring Techniques

Substructuring techniques have been widely used in model reduction of large structures. In these methods a large structure is partitioned into several components and reduced components are built. Boundary degrees-of-freedom (DoF) at the interfaces between components are used to assemble the reduced components and to form a reduced model of the original structure. In the current substructuring methods the boundary DoF or a transformation of these DoF remain in the reduced model. In this paper a methodology is suggested that could eliminate the boundary DoF from the reduced model which in turn leads to having even a smaller reduced model. This method which uses a different partitioning of the DoF of the structure is illustrated for a two-component structure. An example on a simple structure shows how the method can be implemented. The results show that the same level of accuracy compared to a standard substructuring can be obtained with fewer number of DoF in the reduced model.

Proteins and direct methods

1991 ◽  
Vol 197 (3-4) ◽  
Author(s):  
Fan Hai-fu ◽  
Hao Quan ◽  
M. M. Woolfson
Keyword(s):  
First Principles ◽  
Figure Of Merit ◽  
Direct Methods ◽  
Large Structure ◽  
Low Resolution ◽  
Figures Of Merit ◽  
Large Structures ◽  
Resolution Data

AbstractConventional direct methods, which work so well for small structures, are less successful for macromolecules. Where it has been demonstrated that a solution might be found using direct methods it is then found that the usual figures of merit are unable to distinguish the few good sets of phases from the large number of sets generated. The reasons for the difficulties with very large structures are considered from a first-principles approach taking into account both the factors of having a large number of atoms and low resolution data. A proposal is made for trying to recognize good phase sets by taking a large structure as a sum of a number of smaller structures for each of which a conventional figure of merit can be applied.

scholarly journals A possible two-component structure of the non-perturbative Pomeron

2000 ◽  
Vol 486 (1-2) ◽  
pp. 71-76 ◽  
Author(s):  
Pierre Gauron ◽  
Basarab Nicolescu
Keyword(s):  
Component Structure ◽  
Two Component

scholarly journals Learning data-driven reduced elastic and inelastic models of spot-welded patches

2021 ◽  
Vol 22 ◽  
pp. 32
Author(s):  
Agathe Reille ◽  
Victor Champaney ◽  
Fatima Daim ◽  
Yves Tourbier ◽  
Nicolas Hascoet ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Structural Response ◽  
Data Driven ◽  
Fine Scale ◽  
Time Step ◽  
Large Structures ◽  
Computational Performance ◽  
Local Patch ◽  
The Rich ◽  
Learning Data

Solving mechanical problems in large structures with rich localized behaviors remains a challenging issue despite the enormous advances in numerical procedures and computational performance. In particular, these localized behaviors need for extremely fine descriptions, and this has an associated impact in the number of degrees of freedom from one side, and the decrease of the time step employed in usual explicit time integrations, whose stability scales with the size of the smallest element involved in the mesh. In the present work we propose a data-driven technique for learning the rich behavior of a local patch and integrate it into a standard coarser description at the structure level. Thus, localized behaviors impact the global structural response without needing an explicit description of that fine scale behaviors.

scholarly journals Dynamics of the concept CANADA in English-Canadian poetic texts of the 18th–21st centuries

2019 ◽  
Keyword(s):  
Structural Components ◽  
Canadian History ◽  
Component Structure ◽  
Cognitive Characteristics ◽  
Two Component ◽  
Poetic Texts ◽  
English Canadian ◽  
Historical Periods ◽  
Cultural Features ◽  
Selection Of

The article deals with the trends of historical dynamics of linguistic and cognitive characteristics of the concept Canada in English-Canadian poetic texts of the 18th–21st centuries. This research deploys a complex semantic and cognitive analysis of its lexical-semantic nominative means of poetic texts. As a result specific features of national, cultural and author’s knowledge encoded in the poetic texts are identified and classified. The lexical nominative means of the concept Canada are viewed in terms of two groups of nominative means: direct and figurative. All the nominations are classified according to several criteria. Direct and figurative nominative means of the concept Canada variously characterize physical, geographical, territorial, demographic, social, political, historical, and cultural features of the Canadian state. The variability in priority of thematic nomination groups of the concept Canada in different historical periods of the statehood formation reveals the influence of the extralingual factors on the authors’ selection of nominative means of the concept Canada. The concept Canada combines the features of both a literary, cultural and a toponymic concept. It has been modeled as a complex two-component structure that includes a sensory-notional and a figurative component. Historically conditioned transformations of the structural components of the concept Canada is interpreted in terms of its invariant and diachronically variable linguistic and cognitive characteristics. During three periods of Canadian history, the transformations of the structural components of the concept Canada reveal themselves as either the hierarchic shifts of the literary concepts-slots in the sensory-notional component or as the variability of the set of conceptual metaphors in its figurative component.

scholarly journals Implementing model reduction to the JuliaFEM platform

2018 ◽  
Vol 51 (1) ◽  
pp. 36-54 ◽  
Author(s):  
Marja Liisa Rapo ◽  
Jukka Aho ◽  
Hannu Koivurova ◽  
Tero Frondelius
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Model Reduction ◽  
Open Source ◽  
Degrees Of Freedom ◽  
Mass Matrices ◽  
Dynamic Condensation ◽  
Dynamic Analyses ◽  
Reduction Methods ◽  
Large Model

JuliaFEM is an open source finite element method solver written in the Julia language. This paper presents an implementation of two common model reduction methods: the Guyan reduction and the Craig-Bampton method. The goal was to implement these algorithms to the JuliaFEM platform and demonstrate that the code works correctly. This paper first describes the JuliaFEM concept briefly after which it presents the theory of model reduction, and finally, it demonstrates the implemented functions in an example model. This paper includes instructions for using the implemented algorithms, and reference the code itself in GitHub. The reduced stiness and mass matrices give the same results in both static and dynamic analyses as the original matrices, which proves that the code works correctly. The code runs smoothly on relatively large model of 12.6 million degrees of freedom. In future, damping could be included in the dynamic condensation now that it has been shown to work.

Personal Disturbance Scale: Factor Structure Confirmed in a Large Nonclinical Sample

2005 ◽  
Vol 96 (1) ◽  
pp. 107-108 ◽  
Author(s):  
Alan Bedford ◽  
J. D. Henry ◽  
J. R. Crawford
Keyword(s):  
Clinical Study ◽  
Factor Structure ◽  
Short Form ◽  
Psychiatric Patients ◽  
Scale Factor ◽  
Anxiety And Depression ◽  
Component Structure ◽  
Two Component ◽  
Nonclinical Sample

The two-component structure of anxiety and depression items of the short form Personal Disturbance Scale, reported in an earlier clinical study of 480 adult psychiatric patients, was substantially replicated in a large nonclinical sample of 758 adults.

SELF-ORGANIZATION OF FULLERENE C60 MOLECULES IN VOLUME OF EVAPORATING DROPLETS

2018 ◽  
Vol 20 (5) ◽  
pp. 309-314
Author(s):  
U.K. Makhmanov ◽  
A.M. Kokhkharov ◽  
S.A. Bakhramov
Keyword(s):  
Room Temperature ◽  
Ostwald Ripening ◽  
Substrate Surface ◽  
Fullerene C60 ◽  
Chemical Mechanism ◽  
Self Organization ◽  
Flat Substrate ◽  
Large Structures ◽  
Physical Chemical ◽  
Two Component

An efficient method of formation of the ordered fullerene C60 nanoaggregates in the volume of evaporating fullerene droplets in mixtures of two-component solvents (benzene and acetonitrile) on a flat substrate surface at room temperature is demonstrated. The specific physical-chemical mechanism of the synthesis of fullerene C60 aggregates in the volume of the evaporating droplet of solution, so called Ostwald ripening, according to which relatively large structures grow at the expense of smaller ones, has been proposed.

PD Controller With Self Adaptive Gains for Quadrotor Waypoint Navigation

2020 ◽  
Author(s):  
Madhavan Sudakar ◽  
Siddharth Sridhar ◽  
Manish Kumar
Keyword(s):  
Control Algorithm ◽  
Degrees Of Freedom ◽  
Simple Structure ◽  
Reference Model ◽  
Pd Controller ◽  
Lyapunov Stability Analysis ◽  
Waypoint Navigation ◽  
Novel Method ◽  
Model Reference Adaptive ◽  
Random Gain

Abstract Proportional-Derivative (PD) controllers are commonly used in quadrotors due to their simple structure. Tuning of the gains of the PD controller is often cumbersome due to strong coupling of the dynamics between three linear and three angular degrees of freedom. This paper presents a novel method of auto adjusting the proportional and derivative gains of the quadrotor without the use of any stable reference model (unlike model reference adaptive control). The gains are automatically adjusted throughout the flight based on just the state errors. Lyapunov stability analysis and adaptive gain law is used to formulate the control algorithm to achieve way point navigation. It is shown that our proposed controller achieves effective way point navigation even when started off from random gain values.

Plural marking patterns of nouns and their associates in the world’s languages

2020 ◽  
Vol 44 (1) ◽  
pp. 231-269
Author(s):  
Rong Chen
Keyword(s):  
Machine Learning ◽  
Logistic Regression ◽  
Learning Algorithm ◽  
Machine Learning Algorithm ◽  
Data Set ◽  
Component Structure ◽  
Universal Distribution ◽  
Two Component ◽  
The World ◽  
Plural Marking

Abstract Plural marking reaches most corners of languages. When a noun occurs with another linguistic element, which is called associate in this paper, plural marking on the two-component structure has four logically possible patterns: doubly unmarked, noun-marked, associate-marked and doubly marked. These four patterns do not distribute homogeneously in the world’s languages, because they are motivated by two competing motivations iconicity and economy. Some patterns are preferred over others, and this preference is consistently found in languages across the world. In other words, there exists a universal distribution of the four plural marking patterns. Furthermore, holding the view that plural marking on associates expresses plurality of nouns, I propose a hypothetical universal which uses the number of pluralized associates to predict plural marking on nouns. A data set collected from a sample of 100 languages is used to test the hypothetical universal, by employing the machine learning algorithm logistic regression.

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