Knowledge Composition for Efficient Analysis Problem Formulation: Part 1 — Motivation and Requirements

2007 ◽  
Author(s):  
Manas Bajaj ◽  
Russell S. Peak ◽  
Christiaan J. J. Paredis
Keyword(s):  
Gap Analysis ◽  
Problem Formulation ◽  
Analysis Problem ◽  
Element Analysis ◽  
Design Alternatives ◽  
Simulation Based Design ◽  
Variable Topology ◽  
Commercial Off The Shelf ◽  
Multi Body ◽  
Analysis Models

In simulation-based design a key challenge is to formulate and solve analysis problems efficiently to evaluate a variety of design alternatives. Numerically solving analysis problems has benefited from advancements in commercial off-the-shelf mathematical solvers and computational capabilities. However, the formulation of analysis problems for a given set of design alternatives is still typically a laborious and costly process. In the scope of design alternatives with variable topology multi-body (VTMB) characteristics, these papers (Part 1 and Part 2) present research that addresses the following primary question: How can we improve the efficiency of the analysis problem formulation process for VTMB design alternatives? The objective of this paper (Part 1) is to identify requirements for a methodology that answers this. The methodology is formulates analysis problems for VTMB design alternatives based on decisions taken by analysts and independent of the solution method (such as finite element analysis) and the solver. This paper presents a gap analysis using an example VTMB problem and identifies key inadequacies in existing approaches for analysis problem formulation. Based on the gap analysis and technical background, we present five main requirements relating to (a) key drivers for efficiently creating analysis models; (b) abstracting and formalizing analysis knowledge for composing analysis models; and (c) automatically creating, reconfiguring and verifying analysis models.

Knowledge Composition for Efficient Analysis Problem Formulation: Part 2 — Approach and Analysis Meta-Model

2007 ◽  
Author(s):  
Manas Bajaj ◽  
Russell S. Peak ◽  
Christiaan J. J. Paredis
Keyword(s):  
Model Transformation ◽  
Gap Analysis ◽  
Cost Effective ◽  
Building Blocks ◽  
Problem Formulation ◽  
Analysis Model ◽  
Product Model ◽  
Analysis Problem ◽  
Meta Model ◽  
Analysis Models

In Part 1 we presented technical background and a gap analysis leading to the identification of five requirements for a methodology for efficient formulation of analysis problems for VTMB design alternatives. These requirements are founded on (a) abstraction of analysis knowledge as modular, reusable, computer-interpretable, analyst-intelligible building blocks, and (b) automated creation, reconfiguration, and verification of analysis models. In this paper (Part 2), we present an example scenario to overview the Knowledge Composition Methodology (KCM) that is aimed at satisfying these requirements. The methodology is founded on analysis knowledge building blocks and a model transformation process based on graph transformations. With KCM an analyst may automatically compose an analysis model from a design model and these building blocks. In this paper, we focus on the analysis knowledge component of this methodology (illustrated for structural and thermal disciplines), and describe four dimensions of analysis knowledge. Using these dimensions, we develop a decision template for analysts to create specifications for analysis models. Analysis models can be automatically created from a given specification using model transformation techniques (not described in this paper). We leverage the notion of choices and decisions to (a) define primitive and complex building blocks of analysis knowledge, and (b) formalize an analysis meta-model that represents the structure of analysis models. We also relate this analysis meta-model to the NIST Core Product Model (CPM2). The envisioned methodology impact is a formal and systems-oriented foundational approach for analysis problem formulation that is time- and cost-effective.

Modeling Implications in Simulation-Based Design of Stents

2006 ◽  
Author(s):  
Tiefu Shao ◽  
Sundar Krishnamurty
Keyword(s):  
Detailed Comparison ◽  
Surrogate Models ◽  
Process Efficiency ◽  
Element Analysis ◽  
Sampling Schemes ◽  
Simulation Based Design ◽  
Simulation Based ◽  
The Cost ◽  
Design Preferences ◽  
Analysis Models

Variations associated with stenting systems, artery properties, and doctor skills necessitate a better understanding of coronary artery stents so as to facilitate the design of stents that are customized to individual patients. This paper presents the development of an integrated computer simulation-based design approach using engineering finite element analysis (FEA) models for capturing stent knowledge, utility theory-based decision models for representing the design preferences, and statistics-based surrogate models for improving process efficiency. Two focuses of the paper are: 1) understanding the significance of engineering analysis and surrogate models in the simulation-based design of medical devices; 2) investigating the modeling implications in the context of stent design. The study reveals that the advanced nonlinear FEA software with analysis capacities on large deformation and contact interaction has offered a platform to execute high fidelity simulations, yet the selection of appropriate analysis models is still subject to the tradeoff between cost of analysis and accuracy of solution; the cost-prohibitive simulations necessitate the employment of surrogate models in subsequent multi-objective design optimization. A detailed comparison between regression models and Kriging models suggests the importance of sampling schemes in successfully implementing Kriging methods.

Linear Thermomechanical Microactuators

1999 ◽  
Author(s):  
Rebecca Cragun ◽  
Larry L. Howell
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Thermal Expansion ◽  
Cross Sections ◽  
Variable Cross ◽  
Element Analysis ◽  
Thermal Actuators ◽  
Output Force ◽  
Analysis Models ◽  
High Output

Abstract Thermomechanical in-plane microactuators (TIMs) have been designed, modeled, fabricated, and tested. TIMs offer an alternative to arrays of smaller thermal actuators to obtain high output forces. The design is easily modified to obtain the desired output force or deflection for specific applications. The operational principle is based on the symmetrical thermal expansion of variable cross sections of the surface micromachined microdevice. Sixteen configurations of TIMs were fabricated of polysilicon. Finite element analysis models were used to predict the deflection and output force for the actuators. Experimental results were also recorded for all sixteen configurations, including deflections and output forces up to 20 micron and 35 dyne.

A Design Methodology for System Parameters Synthesis of Elastic Planar Linkages: Theory

1992 ◽  
Vol 114 (4) ◽  
pp. 536-541 ◽  
Author(s):  
Zine-Eddine Boutaghou ◽  
A. G. Erdman
Keyword(s):  
Design Methodology ◽  
Design Sensitivity ◽  
Element Analysis ◽  
System Parameters ◽  
Sensitivity Equations ◽  
The Finite Element Analysis ◽  
Planar Linkages ◽  
Multi Body ◽  
Four Bar Linkage ◽  
Theoretical Considerations

Existing formulations predict the displacement and stresses in multi-body systems that result from known system parameters. In contrast, the proposed design methodology enables structured selection of system parameters necessary to produce desired elastic displacements, stresses, and frequencies. This design process involves the development of inverse design equations, the finite element analysis, and the design sensitivity equations to obtain converged solutions satisfying desired design constraints. Part 1 (Theory) considers the theoretical considerations involved. Part 2 (Applications) applies the methodology to design a four-bar linkage and a six-bar linkage.

scholarly journals Training on ant sugar production to increase people's income in Ba'ka Village, Enrekang

2021 ◽  
Vol 6 (7) ◽  
pp. 1133-1138
Author(s):  
Irman Syarif ◽  
Agusriandi Agusriandi ◽  
Elihami Elihami ◽  
Ita Sarmita Samad ◽  
Sry Wahyuni R
Keyword(s):  
Community Service ◽  
Program Implementation ◽  
Problem Formulation ◽  
Needs Analysis ◽  
Sugar Production ◽  
Analysis Problem ◽  
Work Program ◽  
The People ◽  
Service Activity ◽  
Palm Sugar

Most of the people of Ba'ka Village are conventional palm sugar farmers whose whose selling prices are cheap. The purpose of this service is to provide innovation in palm sugar into ant sugar. Through training in making ant sugar, it is hoped that it can increase people's income. The stages of community service include needs analysis, problem formulation, work program formulation, and work program implementation, and evaluation. This service activity produces ant sugar products that are packaged in a modern way. Ant sugar products can attract consumers because they are more durable, hygienic, and practical.

scholarly journals Design of a multifunctional composite structure for modular CubeSat applications

2019 ◽  
Vol 304 ◽  
pp. 07001
Author(s):  
Giorgio Capovilla ◽  
Enrico Cestino ◽  
Leonardo M. Reyneri ◽  
Giulio Romeo
Keyword(s):  
Power System ◽  
Modular Design ◽  
Electrical Power ◽  
Electrical Power System ◽  
Element Analysis ◽  
Array Configuration ◽  
Structural Integration ◽  
Low Degree ◽  
Primary Structures ◽  
Commercial Off The Shelf

CubeSats primary structures are usually made with aluminium alloys, with few examples of CFRP primary structures under study. Power system battery arrays usually occupy spacecraft internal volume and mass that should be available to the payload. A CFRP structural/battery array configuration has been designed, allowing to integrate the electrical power system in the bus primary structure. Its configuration has been developed with the modular design philosophy of the AraMiS CubeSat. It is sized as a tile, mounted on an external face of the 1U CubeSat. It accommodates two solar cells, while the opposite face accommodates power system circuitry. Following a cellular structure concept, a set of commercial LiPo batteries has been placed between two CFRP panels and spaced out with CFRP ribs. Compliance with launch mechanical loads has been evaluated with a finite element analysis. A preliminary thermal analysis has been performed to simulate a LEO orbit environment. The results indicate that even with a low degree of structural integration, more volume and mass can be allocated to the payload, with respect to traditional, functionally separated designs in aluminium alloy. The low degree of integration allows to employ relatively cheap, commercial off-the-shelf components.

Finite-element analysis of multi-body contacts for pile driving using a hydraulic pile hammer

2011 ◽  
Vol 225 (5) ◽  
pp. 1153-1161 ◽  
Author(s):  
Y Guo ◽  
J P Hu ◽  
L Y Zhang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Test Point ◽  
Pile Driving ◽  
Penalty Function Method ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Material Choice ◽  
Multi Body ◽  
The Impact

This article treats the pile driving as multi-body dynamic contacts. By using the penalty function method and three-dimensional model of finite-element method, the dynamic process of pile driving is acquired and a method for choosing the cushion material of the hydraulic pile hammer to improve driving efficiency is proposed. The process of pile driving in the real situation of an industrial experiment is simulated. The results of stress on test point are consistent with the test point. By analysing the stress distributed along the direction of pile radius and pile axis, the rule of the stress distribution on the pile is concluded. The rule for cushion material choice is obtained by comparing the influence for the impact stress with different elastic modulus ratio of the hammer cushion to the pile and the pile cushion to the pile.

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