Accurate Reduction of Stiffness and Mass Matrices for Vibration Analysis and a Rationale for Selecting Master Degrees of Freedom

1980 ◽  
Vol 102 (2) ◽  
pp. 412-416 ◽  
Author(s):  
B. Downs
Keyword(s):  
Dynamic Characteristics ◽  
Vibration Analysis ◽  
Degrees Of Freedom ◽  
Simple System ◽  
Optimal Selection ◽  
Rigorous Solution ◽  
Interpolation Equation ◽  
Mass Matrices ◽  
Initial Selection ◽  
Selection Of

A method is described which permits the reduction of stiffness and mass matrices on to selected degrees of freedom, while accurately retaining, up to a certain cut-off frequency, the dynamic characteristics of the original matrices. The validity of the method is demonstrated by obtaining identical results, for the reduction of a simple system, with those derived from a rigorous solution. An interpolation equation is also developed which allows the eigenvector components on the eliminated degrees of freedom to be determined accurately from the ‘master’ components. Some guidelines are provided for the optimal selection of the ‘master’ degrees of freedom and a procedure defined for progressively improving the initial selection, prior to undertaking the eigenvalue analysis.

scholarly journals Optimal Selection of Measurement Configurations for Stiffness Model Calibration of Anthropomorphic Manipulators

2012 ◽  
Vol 162 ◽  
pp. 161-170 ◽  
Author(s):  
Alexandr Klimchik ◽  
Yier Wu ◽  
Anatol Pashkevich ◽  
Stéphane Caro ◽  
Benoît Furet
Keyword(s):  
Model Calibration ◽  
Degrees Of Freedom ◽  
Optimal Selection ◽  
Robot Calibration ◽  
Test Configuration ◽  
Practical Applications ◽  
Stiffness Model ◽  
New Strategy ◽  
Actuated Joints ◽  
Selection Of

The paper focuses on the calibration of elastostatic parameters of spatial anthropomorphic robots. It proposes a new strategy for optimal selection of the measurement configurations that essentially increases the efficiency of robot calibration. This strategy is based on the concept of the robot test-pose and ensures the best compliance error compensation for the test configuration. The advantages of the proposed approach and its suitability for practical applications are illustrated by numerical examples, which deal with calibration of elastostatic parameters of a 3 degrees of freedom anthropomorphic manipulator with rigid links and compliant actuated joints.

Application of L6 Orthogonal Array for Optimal Selection of Some Process Parameters in GMAW Process

2012 ◽  
Vol 45 (4) ◽  
pp. 41 ◽  
Author(s):  
M. K. Saha ◽  
Santanu Das ◽  
A. Bandyopadhyay ◽  
S. Bandyopadhyay
Keyword(s):  
Process Parameters ◽  
Orthogonal Array ◽  
Optimal Selection ◽  
Selection Of

Application of L6 Orthogonal Array for Optimal Selection of Some Process Parameters in GMAW Process

2012 ◽  
Vol 45 (4) ◽  
pp. 41
Author(s):  
M. K. Saha ◽  
Santanu Das ◽  
A. Bandyopadhyay ◽  
S. Bandyopadhyay
Keyword(s):  
Process Parameters ◽  
Orthogonal Array ◽  
Optimal Selection ◽  
Selection Of

A Court of Specialists

2020 ◽  
Author(s):  
Chris Hanretty
Keyword(s):  
Family Law ◽  
Public Law ◽  
Tax Law ◽  
Decision Making Process ◽  
Main Argument ◽  
Political Differences ◽  
Uk Supreme Court ◽  
The Uk ◽  
Initial Selection ◽  
Selection Of

This book explains how judges on the UK Supreme Court behave. It looks at different stages in the court's decision-making process—from the initial selection of cases, to the choice of judges to sit on panels, to the final outcome. The main argument of the book is that judges' behavior is strongly affected by their specialism in different areas of law. Cases in tax law (or family law, or public law) are more likely to be heard by specialists in that area, and those specialists are more likely to write the court's decision—or disagree with the decision when there is dissent. Legal factors like specialization in areas of law explains more of the court's work than do political differences between judges.

scholarly journals Methodology for Determining the Location of River Ports on a Modernized Waterway Based on Non-Cost Criteria: A Case Study of the Odra River Waterway

2021 ◽  
Vol 13 (6) ◽  
pp. 3571
Author(s):  
Bogusz Wiśnicki ◽  
Dorota Dybkowska-Stefek ◽  
Justyna Relisko-Rybak ◽  
Łukasz Kolanda
Keyword(s):  
Large Scale ◽  
Multicriteria Decision Making ◽  
Research Process ◽  
Optimal Selection ◽  
Investment Projects ◽  
Odra River ◽  
Research Problems ◽  
Selection Of ◽  
Construction Works

The paper responds to research problems related to the implementation of large-scale investment projects in waterways in Europe. As part of design and construction works, it is necessary to indicate river ports that play a major role within the European transport network as intermodal nodes. This entails a number of challenges, the cardinal one being the optimal selection of port locations, taking into account the new transport, economic, and geopolitical situation that will be brought about by modernized waterways. The aim of the paper was to present an original methodology for determining port locations for modernized waterways based on non-cost criteria, as an extended multicriteria decision-making method (MCDM) and employing GIS (Geographic Information System)-based tools for spatial analysis. The methodology was designed to be applicable to the varying conditions of a river’s hydroengineering structures (free-flowing river, canalized river, and canals) and adjustable to the requirements posed by intermodal supply chains. The method was applied to study the Odra River Waterway, which allowed the formulation of recommendations regarding the application of the method in the case of different river sections at every stage of the research process.

scholarly journals Optimal Selection of Conductors in Three-Phase Distribution Networks Using a Discrete Version of the Vortex Search Algorithm

Computation ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 80
Author(s):  
John Fernando Martínez-Gil ◽  
Nicolas Alejandro Moyano-García ◽  
Oscar Danilo Montoya ◽  
Jorge Alexander Alarcon-Villamil
Keyword(s):  
Objective Function ◽  
Power Flow ◽  
Phase Distribution ◽  
Search Algorithm ◽  
Distribution Networks ◽  
Discrete Version ◽  
Optimal Selection ◽  
Flow Method ◽  
Three Phase ◽  
Selection Of

In this study, a new methodology is proposed to perform optimal selection of conductors in three-phase distribution networks through a discrete version of the metaheuristic method of vortex search. To represent the problem, a single-objective mathematical model with a mixed-integer nonlinear programming (MINLP) structure is used. As an objective function, minimization of the investment costs in conductors together with the technical losses of the network for a study period of one year is considered. Additionally, the model will be implemented in balanced and unbalanced test systems and with variations in the connection of their loads, i.e., Δ− and Y−connections. To evaluate the costs of the energy losses, a classical backward/forward three-phase power-flow method is implemented. Two test systems used in the specialized literature were employed, which comprise 8 and 27 nodes with radial structures in medium voltage levels. All computational implementations were developed in the MATLAB programming environment, and all results were evaluated in DigSILENT software to verify the effectiveness and the proposed three-phase unbalanced power-flow method. Comparative analyses with classical and Chu & Beasley genetic algorithms, tabu search algorithm, and exact MINLP approaches demonstrate the efficiency of the proposed optimization approach regarding the final value of the objective function.

Sign in / Sign up

Export Citation Format

Share Document