An Integrated Kinematic-Kinetostatic Approach to Optimal Design of Planar Mechanisms Using Fuzzy Theories

1991 ◽  
Vol 113 (3) ◽  
pp. 306-311 ◽  
Author(s):  
A. K. Dhingra ◽  
S. S. Rao
Keyword(s):  
Nonlinear Programming ◽  
High Speed ◽  
Integrated Approach ◽  
Problem Formulation ◽  
Optimization Techniques ◽  
Motion Path ◽  
Programming Formulation ◽  
Planar Mechanisms ◽  
Motion Characteristics ◽  
And Function

A new integrated approach to the design of high speed planar mechanisms is presented. The resulting nonlinear programming formulation combines both the kinematic and kinetostatic synthesis aspects of mechanism design. The multiobjective optimization techniques presented in this work facilitate the design of a linkage to meet several kinematic and dynamic design criteria. The method can be used for motion, path, and function generation problems. The nonlinear programming formulation also permits an imposition of constraints to eliminate solutions which possess undesirable kinematic and motion characteristics. To model the vague and imprecise information in the problem formulation, the tools of fuzzy set theory have been used. A novel method of solving the resulting fuzzy multiobjective problem using mathematical programming techniques is presented. The outlined procedure is expected to be useful in situations where doubt arises about the exactness of permissible values, degree of credibility, and correctness of statements and judgements.

Integrated Optimal Design of Planar Mechanisms Using Fuzzy Theories

1989 ◽  
Author(s):  
A. K. Dhingra ◽  
S. S. Rao
Keyword(s):  
Nonlinear Programming ◽  
High Speed ◽  
Integrated Approach ◽  
Problem Formulation ◽  
Optimization Techniques ◽  
Motion Path ◽  
Programming Formulation ◽  
Planar Mechanisms ◽  
Dynamic Synthesis ◽  
Motion Characteristics

Abstract A new integrated approach to the design of high speed planar mechanisms is presented. The resulting nonlinear programming formulation combines both the kinematic and dynamic synthesis aspects of mechanism design. The multiobjective optimization techniques presented in this work facilitate the design of a linkage to meet several kinematic and dynamic design criteria. The method can be used for motion, path, and function generation problems. The nonlinear programming formulation also permits the imposition of constraints to eliminate solutions which possess undesirable kinematic and motion characteristics. To model the vague and imprecise information in the problem formulation, the tools of fuzzy set theory have been used. A method of solving the resulting fuzzy multiobjective problem using mathematical programming techniques is presented. The outlined procedure is expected to be useful in situations where doubt arises about the exactness of permissible values, degree of credibility, and correctness of statements and judgements.

Integrated Kinematic and Dynamic Optimal Design of Flexible Planar Mechanisms

1987 ◽  
Vol 109 (3) ◽  
pp. 338-347 ◽  
Author(s):  
A. J. Kakatsios ◽  
S. J. Tricamo
Keyword(s):  
Cross Sections ◽  
High Speed ◽  
Integrated Approach ◽  
Programming Formulation ◽  
Kinematic Parameters ◽  
Planar Mechanisms ◽  
Disturbing Force ◽  
Design Requirements ◽  
Path Synthesis ◽  
Flexible Mechanisms

The following describes a new integrated approach to the problem of designing high speed mechanisms. Employing a nonlinear programming formulation, it allows both the kinematic parameters and the link cross sections to vary while simultaneously bounding trajectory accuracy and minimizing the disturbing force on the ground. Furthermore, link stresses are bounded to limits imposed by the designer. The technique is capable of taking into account the complex coupling which exists between kinematic and dynamic characteristics in flexible mechanisms to determine linkage parameters which best satisfy a given set of design requirements. A path synthesis problem is used to illustrate the technique.

Optimal Balancing of High-Speed Linkages Using Multiobjective Programming Techniques

1986 ◽  
Vol 108 (4) ◽  
pp. 454-460 ◽  
Author(s):  
S. S. Rao ◽  
R. L. Kaplan
Keyword(s):  
High Speed ◽  
Goal Attainment ◽  
Optimization Methods ◽  
Optimization Techniques ◽  
External Loading ◽  
Planar Mechanisms ◽  
Joint Friction ◽  
Lexicographic Method ◽  
Programming Techniques ◽  
Four Bar Linkage

The application of multiobjective optimization techniques to minimize the dynamic reactions of planar mechanisms is studied. A systems-oriented procedure, which can easily incorporate variable angular velocity input as well as joint friction and external loading, is used for the dynamic analysis of the mechanisms. Goal programming, goal attainment, and a combined bounded objective function/lexicographic method are outlined as solution procedures. These optimization methods are implemented using a computer program based on an exterior penalty function approach. An example four-bar linkage is considered for illustration and the results obtained with different methods of optimization are reportred. It is observed that the methods presented in this paper offer greater flexibility and wider application in the optimal balancing of high-speed linkages.

Optimum Balancing of Combined Shaking Force, Shaking Moment, and Torque Fluctuations in High-Speed Linkages

1984 ◽  
Vol 106 (2) ◽  
pp. 242-251 ◽  
Author(s):  
T. W. Lee ◽  
C. Cheng
Keyword(s):  
High Speed ◽  
Optimization Technique ◽  
Integrated Approach ◽  
Optimization Techniques ◽  
Theoretical Development ◽  
Design Stage ◽  
Heuristic Optimization ◽  
Analytical Mechanics ◽  
Trade Offs ◽  
Shaking Moment

This paper presents an analytical and computer-aided procedure on the balancing of high-speed linkages. The method allows for the trade-offs necessary to achieve optimum dynamic response of the linkage in the design stage. These trade-offs involve a balance among the shaking force, the shaking moment, bearing reactions, and input-torque fluctuations by mass distribution of the links or counterweighting the linkage. Analytical mechanics and heuristic optimization techniques have been demonstrated to be useful tools in developing such a trade-off. The first part of this paper concerns the development of an optimality criterion in which an integrated approach is presented using both the Lagrangian and the Newtonian formulations, and consequently, a higher computational efficiency is achieved. Based on this theoretical development, the remainder of the paper focuses on the formulation of an optimization problem for linkage balancing and the solution of the problem by the Heuristic Optimization Technique of Lee and Freudenstein. The theory and computation are illustrated by numerical examples in the case of four-bar linkages.

Evolutionary Based Optimal Synthesis of Four-Bar Mechanisms

2003 ◽  
Author(s):  
D. Koladiya ◽  
P. S. Shiakolas ◽  
J. Kebrle
Keyword(s):  
Optimization Techniques ◽  
Optimization Approach ◽  
Path Generation ◽  
Planar Mechanisms ◽  
Function Generation ◽  
Novel Technique ◽  
Optimum Synthesis ◽  
Design Variables ◽  
Accuracy Level ◽  
And Function

Graphical and analytical syntheses have been well applied to path, motion and function generation of planar mechanisms. Optimization techniques in common, require “good initial guesses” and do not necessarily converge to a solution. This paper presents a methodology to synthesize mechanisms employing an evolutionary optimization approach technique known as Differential Evolution. The initial bounds for the design variables are defined automatically using a newly developed and novel technique called the Geometric Centroid of Precision Points. Optimum synthesis of four-bar linkages for path generation with user defined accuracy level at required precision points is discussed.

Ausnahmesegment

2018 ◽  
Vol 48 (191) ◽  
Author(s):  
Barbara Schönig
Keyword(s):  
Welfare State ◽  
Social Housing ◽  
Integrated Approach ◽  
New Paradigm ◽  
Development Models ◽  
Form And Function ◽  
Institutional Organization ◽  
National Welfare ◽  
And Function ◽  
The Welfare State

Going along with the end of the “golden age” of the welfare state, the fordist paradigm of social housing has been considerably transformed. From the 1980s onwards, a new paradigm of social housing has been shaped in Germany in terms of provision, institutional organization and design. This transformation can be interpreted as a result of the interplay between the transformation of national welfare state and housing policies, the implementation of entrepreneurial urban policies and a shift in architectural and urban development models. Using an integrated approach to understand form and function of social housing, the paper characterizes the new paradigm established and nevertheless interprets it within the continuity of the specific German welfare resp. housing regime, the “German social housing market economy”.

scholarly journals Characterization of the G protein-coupled receptor family SREB across fish evolution

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Timothy S. Breton ◽  
William G. B. Sampson ◽  
Benjamin Clifford ◽  
Anyssa M. Phaneuf ◽  
Ilze Smidt ◽  
...  
Keyword(s):  
G Protein ◽  
Genomic Structure ◽  
Integrated Approach ◽  
Orphan Receptor ◽  
Specific Gene ◽  
Testicular Development ◽  
Brain Expression ◽  
And Function ◽  
G Protein Coupled ◽  
Receptor Family

AbstractThe SREB (Super-conserved Receptors Expressed in Brain) family of G protein-coupled receptors is highly conserved across vertebrates and consists of three members: SREB1 (orphan receptor GPR27), SREB2 (GPR85), and SREB3 (GPR173). Ligands for these receptors are largely unknown or only recently identified, and functions for all three are still beginning to be understood, including roles in glucose homeostasis, neurogenesis, and hypothalamic control of reproduction. In addition to the brain, all three are expressed in gonads, but relatively few studies have focused on this, especially in non-mammalian models or in an integrated approach across the entire receptor family. The purpose of this study was to more fully characterize sreb genes in fish, using comparative genomics and gonadal expression analyses in five diverse ray-finned (Actinopterygii) species across evolution. Several unique characteristics were identified in fish, including: (1) a novel, fourth euteleost-specific gene (sreb3b or gpr173b) that likely emerged from a copy of sreb3 in a separate event after the teleost whole genome duplication, (2) sreb3a gene loss in Order Cyprinodontiformes, and (3) expression differences between a gar species and teleosts. Overall, gonadal patterns suggested an important role for all sreb genes in teleost testicular development, while gar were characterized by greater ovarian expression that may reflect similar roles to mammals. The novel sreb3b gene was also characterized by several unique features, including divergent but highly conserved amino acid positions, and elevated brain expression in puffer (Dichotomyctere nigroviridis) that more closely matched sreb2, not sreb3a. These results demonstrate that SREBs may differ among vertebrates in genomic structure and function, and more research is needed to better understand these roles in fish.

Individual differences in political aggression: The role of social integration, perceived grievances and low self-control

2018 ◽  
Vol 17 (5) ◽  
pp. 603-627 ◽  
Author(s):  
Lieven J.R. Pauwels ◽  
Vanja Ljujic ◽  
Ann De Buck
Keyword(s):  
Individual Differences ◽  
Social Integration ◽  
Structural Equation ◽  
Integrated Approach ◽  
Self Control ◽  
Content Support ◽  
Log Linear ◽  
Low Self Control ◽  
And Function

Several models have been suggested for studying (self-reported) aggression. Less frequently, these theories are empirically applied to explain individual differences in political aggression. The present study examines the role of distal, intermediate and proximate mechanisms in a net-sample of 6020 young adults. Using log-linear structural equation modelling, the independent effects of cumulative social integration, perceived personal and group injustices and low self-control are assessed. It is assumed that these factors contribute to the ‘crystallization of discontent’ by fostering religious authoritarianism, political powerlessness, support for extremist beliefs and online exposure to extremist content. Support for extremist content and online exposure to extremist content are strong predictors, and function as different routes towards political aggression. The results support an integrated approach towards the study of political aggression. Implications for future studies are discussed.

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