Glossary#

AAO#

All At Once

algorithm integrator#

A user class of the formulation engine that integrates mathematical algorithms such as an optimization algorithm, DOE method or surrogate model

anaconda#

A python tool to create virtual environment and easily install precompiled packages, https://www.anaconda.com/distribution

ANN#

Artificial Neural Network

ANR#

Agence Nationale de la Recherche

API#

Application Program Interface

ASO#

Asymmetric Subspace Optimization

ATC#

Analytical Target Cascading

bi-level#

A type of MDO formulation which formulates multiple optimization problems

BLISS#

Bi-Level Integrated System Synthesis,

BLISS2000#

Bi-Level Integrated System Synthesis, BLISS variant from 2000 paper, using surrogate models

BLISS98#

Bi-Level Integrated System Synthesis, original BLISS variant from 1998 paper using coupled derivatives

CFD#

Computational Fluid Dynamics

chain#

A process that executes a set of disciplines in a sequential way, where outputs of the previously executed disciplines are passed as inputs of the next ones

CO#

Collaborative Optimization

complex step#

A numerical method to approximate the derivative of a function, similarly to finite differences, but using complex perturbations

constraint#

A function of the design variables that must be kept either null or negative in an optimization problem

constraints#

All the functions of the design variables that must be kept either null or negative in an optimization problem

COTS#

Commercial Off The Shelf

coupling variables#

In an MDO scenario, variables that are both used as inputs of a discipline and outputs of another one, or the same discipline

CSM#

Computational Structure Mechanics

CSSO#

Concurrent Subspaces Optimization

data flow#

The sequence of data creation by, and exchanges between disciplines in a process

data-driven#

Characteristic of a workflow engine, for which processes are described through the data flow, and in which the work flow is deduced accordingly

design document#

A document that describes the design of a program, responding to a Software Requirements Specification

Design Of Experiments#

A sampling of a design space, or a generic method that produces samplings of design spaces

design problem#

An engineering problem such that a shape has to be changed to match or improve criteria under constraints

design space#

The mathematical set containing the design variables of an optimization problem

design variables#

The unknowns of the optimization problem

DFO#

Derivative-Free Optimization

disciplinary design variables#

In an MDO scenario, a subset of the design variables that are inputs of only one discipline

disciplinary expert#

A user class of the MDO platform that wraps disciplinary capabilities into disciplines and creates, tests or maintains disciplinary processes

disciplinary optimization#

The most basic MDO formulation restricted to a single set of design variables and only suited for a weakly coupled problem

discipline#

One program, or an arbitrary set of simulation software, that can be viewed as a mathematical multivalued function, taking inputs and producing outputs through its execution

DOE#

Design Of Experiments

DOE algorithm#

An algorithm that generates samples of the design space

driver#

A optimization algorithm or DOE

EA#

Evolutionary Algorithm

eWORMS#

eclipse Workflow Management System

finite differences#

A numerical method to approximate the derivative of a function by small perturbations of the inputs

fixed-point#

A family of numerical resolution methods based on an iterative sequence of execution of the type : A() -> B() -> C() -> ... -> A() -> B() -> C() until convergence

FPO#

Future Projects Office

GEMSEO#

Generic Engine for Multi-disciplinary Scenarios, Exploration and Optimization

generic process#

A process that can be applied to any discipline or set of disciplines, such as Multi Disciplinary Analyses methods that solves the coupling variables of a set of disciplines

gradient#

Total derivative of a function with respect to its variables

gradient-based optimization#

A class of optimization algorithms that use the total derivatives of the objective function and constraints

grammar#

A set of rules to be respected by a data set. Typically used to describe the inputs and outputs of a discipline

HDF#

Hierarchical Data Format to save and structure files with huge data

Hessian#

The matrix of second order partial derivatives of one output with respect to inputs

HPC#

High Performance Computing

HTML#

Hypertext Markup Language

IDF#

Individual Discipline Feasible

interface#

A set of functions and data from a software exposed to other software

IRT#

Institut de Recherche Technologique Saint Exupéry

IVP#

Initial Value Problem

jacobian#

The matrix of first order partial derivatives of outputs with respect to inputs

job scheduler#

A program used to distribute tasks and allocate resources for tasks on HPC clusters

JSON#

JavaScript Object Notation

JSON schema#

A JSON description of JSON data, similar to XML schemas

KKT#

Karun Kuhn Tucker

LHS#

Latin Hypercube Sampling

library wrapper#

A code that translates the existing API of a program, or a library, into a compatible one

local design variables#

In an MDO scenario, a subset of the design variables that are inputs of only one discipline

LOO#

Leave One Out

LP#

Linear Programming

LSF#

COTS jobs scheduler for HPC clusters

MDA#

Multi-Disciplinary Analysis

MDF#

Multi-Disciplinary Feasible

MDO#

Multi-Disciplinary Design Optimization

MDO architecture#

the software architecture that enables the programming and resolution of MDO design problems

MDO formulation#

The mathematical strategy used to define the optimization problem(s) to be solved

MDO formulations designer#

A user class of GEMSEO that creates, implements, tests or maintains MDO formulations

MDO formulations engine#

A program that enables the implementation of MDO formulations

MDO integrator#

A user class that uses disciplines and MDO formulations to create, test and maintain MDO scenarios

MDO platform#

A set of programs integrated in a common framework, enabling the resolution of multidisciplinary engineering problems using numerical simulation and optimization

MDO user#

A user class of the MDO platform that executes an MDO scenario to produce results

MDOIS#

MDO of Independent Subspaces

MMA#

Method of Moving Asymptotes

Model Center#

COTS workflow engine developed by Phoenix Integration

modular architecture#

A software architecture based on separated components, with a relative independence between them

Monolithic#

A type of MDO formulation which formulates a single optimization problem

Newton-Raphson method#

A root finding method that uses successive linear approximations of the function of interest

NLopt#

Non-Linear Optimization package, an open source library of optimization algorithms from MIT, http://ab-initio.mit.edu/nlopt

Object Oriented Programming#

A programming paradigm based on objects, which are data structures as well as a structure for methods

objective function#

The function to be minimized or maximized in an optimization problem

ODE#

Ordinary Differential Equation

OpenDACE#

Open Design and Analysis of Computer Experiments: a program developed by Airbus to standardize interfaces of optimization algorithms, DOE methods and surrogate models as well as the related problems to be solved

operating condition#

An input parameter of a simulation program that defines a physical parameter in which the system operates. Typically the speed of a vehicle, or its altitude

optimization algorithm#

An algorithm capable of solving optimization problems

optimization history#

The database of values of the objective function, constraints and design variables obtained during an optimization

optimization problem#

A mathematical problem consisting in finding a set of variables which minimizes or maximizes a mathematical function (possibly a set-valued map), while satisfying constraints on these variables or on arbitrary functions

optimum#

Solution of an optimization problem: the design variables values at the minimum of the function, subject to the constraints

PIDO#

Process Integration and Design Optimization

pip#

The PyPA recommended tool for installing Python packages. https://pypi.python.org/pypi/pip

process#

A series of executions and data exchanges, ie the workflow and the data flow.

processes data#

The disciplines inputs and generated outputs during the execution of a process

RBF#

Radial Basis Function

root finding#

A family of numerical resolution methods that solves multivariate problems of the type R(x)=0

run time#

In computer science, run time, runtime or execution time is the time during which a program is running (executing), in contrast to other program life cycle phases such as compile time, link time and load time

SAND#

Simultaneous Analysis and Design

SBO#

Surrogate Based Optimization

scenario#

The translation of a design problem into an executable. When executed, a scenario generates a process

Scilab#

An open-source alternative to Matlab

SciPy#

Open Source Library of Scientific Tools, containing a library of optimization algorithms, https://scipy.org

Secure Shell#

(SSH) an encrypted network protocol for accessing remote computers

sequence diagram#

A UML diagram that shows objects execution sequence, such as the function calls and their arguments, and the execution order

serialization#

Process of writing objects or data structures to disk or more generally, to formats that can be stored

shared design variables#

The design variables that are shared by more than one discipline

simulation software#

A program that simulates a part of the physics of a system, or contributes to the overall simulation of the system, such as a mesher

SLM#

Simulation Life Cycle Management

SLSQP#

Sequential Least Squares Quadratic Programming

SOM#

Self Organizing Map

SRS#

Software Requirements Specification

SSBJ#

SuperSonic Business Jet

surrogate model#

A mathematical model of another model. Typically used to substitute an expensive simulation-based model by an approximation whose cost of evaluation is lower, at the price of an initial sampling of the original model

SWIG#

Simplified Wrapper and Interface Generator

system design variables#

The design variables that are shared by more than one discipline, at the system level optimization problem in a bi level MDO scenario

trade-off#

A study that aims at comparing different options in terms of design parameters, and analyse their impacts

UML#

Unified Modeling Language

weakly coupled problem#

A multidisciplinary problem where the coupling variables can be computed by a single execution chain

work flow#

The execution sequence of the disciplines in a process

workflow engine#

A program used to design, run and analyze processes

workflow-driven#

Characteristic of a workflow engine, for which processes are described through the work flow, and in which the data flow is deduced accordingly

WORMS#

Workflow Management System

wrapper#

Here discipline wrappers. Standardized interface defining inputs, outputs and execution of a given simulation software.

XDSM#

eXtended Design Structure Matrix

XML#

Extensible Markup Language