38 research outputs found
A modular genetic programming system
Genetic Programming (GP) is an evolutionary algorithm for the automatic
discovery of symbolic expressions, e.g. computer programs or mathematical
formulae, that encode solutions to a user-defined task. Recent advances in GP
systems and computer performance made it possible to successfully apply this
algorithm to real-world applications.
This work offers three main contributions to the state-of-the art in GP
systems:
(I) The documentation of RGP, a state-of-the art GP software implemented as an
extension package to the popular R environment for statistical computation and
graphics. GP and RPG are introduced both formally and with a series of tutorial
examples. As R itself, RGP is available under an open source license.
(II) A comprehensive empirical analysis of modern GP heuristics based on the
methodology of Sequential Parameter Optimization. The effects and interactions
of the most important GP algorithm parameters are analyzed and recommendations
for good parameter settings are given.
(III) Two extensive case studies based on real-world industrial applications.
The first application involves process control models in steel production,
while the second is about meta-model-based optimization of cyclone dust
separators. A comparison with traditional and modern regression methods
reveals that GP offers equal or superior performance in both applications,
with the additional benefit of understandable and easy to deploy models.
Main motivation of this work is the advancement of GP in real-world application
areas. The focus lies on a subset of application areas that are known to be
practical for GP, first of all symbolic regression and classification. It has
been written with practitioners from academia and industry in mind
Simulation and Optimization of Cyclone Dust Separators
Cyclone Dust Separators are devices often used to filter solid particles from flue gas. Such cyclones are supposed to filter as much solid particles from the carrying gas as possible. At the same time, they should only introduce a minimal pressure loss to the system. Hence, collection efficiency has to be maximized and pressure loss minimized. Both the collection efficiency and pressure loss are heavily influenced by the cyclones geometry. In this paper, we optimize seven geometrical parameters of an analytical cyclone model. Furthermore, noise variables are introduced to the model, representing the non-deterministic structure of the real-world problem. This is used to investigate robustness and sensitivity of solutions. Both the deterministic as well as the stochastic model are optimized with an SMS-EMOA. The SMS-EMOA is compared to a single objective optimization algorithm. For the harder, stochastic optimization problem, a surrogate-model-supported SMS-EMOA is compared against the model-free SMS-EMOA. The model supported approach yields better solutions with the same run-time budget
Quantum state preparation and macroscopic entanglement in gravitational-wave detectors
Long-baseline laser-interferometer gravitational-wave detectors are operating
at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within
a broad frequency band. Such a low classical noise budget has already allowed
the creation of a controlled 2.7 kg macroscopic oscillator with an effective
eigenfrequency of 150 Hz and an occupation number of 200. This result, along
with the prospect for further improvements, heralds the new possibility of
experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical
behavior of objects in the realm of everyday experience - using
gravitational-wave detectors. In this paper, we provide the mathematical
foundation for the first step of a MQM experiment: the preparation of a
macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum
state, which is possible if the interferometer's classical noise beats the SQL
in a broad frequency band. Our formalism, based on Wiener filtering, allows a
straightforward conversion from the classical noise budget of a laser
interferometer, in terms of noise spectra, into the strategy for quantum state
preparation, and the quality of the prepared state. Using this formalism, we
consider how Gaussian entanglement can be built among two macroscopic test
masses, and the performance of the planned Advanced LIGO interferometers in
quantum-state preparation
A Friendly Introduction to RGP
RGP is genetic programming system based on, as well as fully integrated into, the R environment. The system implements classical tree-based genetic programming as well as other variants including, for example, strongly typed genetic programming and Pareto genetic programming. It strives for high modularity through a consistent architecture that allows the customization and replacement of every algorithm component, while maintaining accessibility for new users by adhering to the "convention over configuration" principle
FIWA - Computational Intelligence Methods for Prediction Models in Finance- and Watermanagement
Dieser Schlussbericht beschreibt die im Projekt „Methoden der Computational Intelligence für Vorhersagemodelle in der Finanzund Wasserwirtschaft“ (FIWA) im Zeitraum von Juni 2009 bis einschließlich November 2012 erzielten Ergebnisse. In der Praxis werden für diese Vorhersagemodelle Verfahren der linearen und nichtlinearen Regression, NN, Support Vector Machines (SVM) und viele weitere Verfahren eingesetzt. Das Projekt FIWA befasste sich mit der Entwicklung modularer Systeme zur Analyse und Prognose von Daten aus der Finanz- und Wasserwirtschaft mittels Verfahren der Computational Intelligence (CI) mit methodischem Fokus auf dem CI-Unterbereich Genetic Programming (GP). Ein zentrales Ergebnis der wissenschaftlichtechnischen Arbeit im Projekt FIWA ist die Entwicklung der Open-Source Software RGP. Dabei handelt es sich um ein Software- Framework für GP, welches auf die automatische Erstellung von Vorhersagemodellen spezialisiert ist. Für die Finanzwirtschaft stand ein Handelssimulator zu Verfügung, der auf Basis von echten Finanzdaten die Qualität verschiedener Strategien testen kann. Dieser wurde im Projekt weiterentwickelt. GP wurde genutzt, um auf Basis der Simulationen genaue Vorhersagen und damit verbesserte Handelsstrategien zu entwerfen. Auch für die Wasserwirtschaft wurden Prognoseverfahren mit GP entwickelt. Der Schwerpunkt lag dabei auf der Füllstandprognose für Regenüberlaufbecken. Hier konnten moderne Verfahren mit GP oder SVM klassische Methoden deutlich schlagen oder verbessern. Auch der Einsatz von Sequentieller Parameter Optimierung zeigte signifikante Verbesserungen für die Prognosegenauigkeit. Dabei war die Kombination von klassischen Methoden und GP besonders erfolgreich. GP ist nach wie vor ein sehr aktives Forschungsgebiet und erlaubt auch für die Folgezeit zahlreiche Kooperationen mit den Partnern der Fachhochschule Köln. Sowohl für technische Anwendungen als auch zur Lösung von Forschungsfragen bieten sich zahlreiche Möglichkeiten an.This report describes results achieved in the project "Computational Intelligence Methods for Forecasting Models in Finance and Water Resource Management" (FIWA) during the time frame from July 2009 to November 2012. In practice, these forecasting models are created with methods of linear- and non-linear-regression, NN, Support Vector Machines and many others. The FIWA project developed modular systems for the analysis and forecasting of data from finance and water resource management by Computational Intelligence (CI) methods, with a focus on Genetic Programming (GP). A central result is the development of the open-source software RGP, a GP-system optimized for the automatic generation of forecasting models. For finance application, a trading simulator was extended to be able to efficiently test the quality of trading strategies based on real-world data. GP was employed to generate improved strategies based on these simulations. GP was also used to generate forecasting models for water resource management. An application focus was the forecasting of fill levels of storm water tanks. Modern methods like GP and SVM where able to generate significantly better results than classical methods. Sequential Parameter Optimization was able to further improve these results. GP is a very active field of research and enables multiple cooperations with partners of the Cologne Universtiy of Applied Sciences for commercial and scientific applications
MCIOP - Mehrkriterielle CI-basierte Optimierungsverfahren für den industriellen Einsatz
Ziel des Forschungsprojektes "Mehrkriterielle CI-basierte Optimierungsverfahren für den industriellen Einsatz" (MCIOP) war die Verringerung von Schadstoffemissionen in Kohlekraftwerken. Der wissenschaftliche Fokus lag auf der Entwicklung von Methoden, die in der Lage sind, interpretierbare Modelle für die Schadstoffemissionen automatisch zu generieren. Hierzu wurden mehrkriterielle Optimierungsverfahren entwickelt und eingesetzt. Zur Zeit- und Kostenreduktion wurde die Optimierung durch Surrogat-Modelle erfolgen, die abgestuft mit aufwändigeren Simulationen zum Einsatz kamen („optimization via simulation“). Bei der Untersuchung von Staubabscheidern konnten durch eine mehrkriterielle Optimierung unterschiedliche Zielgrößen, wie z.B. Abscheidegrad und Druckverlust, gleichzeitig berücksichtigt werden.
Dieser Bericht beschreibt die im Projekt MCIOP im Zeitraum von August 2011 bis einschließlich Juni 2015 erzielten Ergebnisse