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%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Additional 'theorem' and 'definition' blocks: \theoremstyle{plain} \newtheorem{theorem}{Theorem}[section] %\newtheorem{theorem}{Satz}[section] % Wenn in Deutsch geschrieben wird. \newtheorem{axiom}{Axiom}[section] %\newtheorem{axiom}{Fakt}[chapter] % Wenn in Deutsch geschrieben wird. %Usage:%\begin{axiom}[optional description]%Main part%\end{fakt} \theoremstyle{definition} \newtheorem{definition}{Definition}[section] %Additional types of axioms: \newtheorem{lemma}[axiom]{Lemma} \newtheorem{observation}[axiom]{Observation} %Additional types of definitions: \theoremstyle{remark} %\newtheorem{remark}[definition]{Bemerkung} % Wenn in Deutsch geschrieben wird. \newtheorem{remark}[definition]{Remark} %%%%%%%%%%%%%%%%%%%%%%%%%%%% % Provides TODOs within the margin: \newcommand{\TODO}[1]{\marginpar{\emph{\small{{\bf TODO: } #1}}}} %%%%%%%%%%%%%%%%%%%%%%%%%%%% % Abbreviations and mathematical symbols \newcommand{\modd}{\text{ mod }} \newcommand{\RS}{\mathbb{R}} 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\thispagestyle{empty} \hspace{1cm} \newpage %%%%%%%%%%%%%%%%%%%%%%%%%%%% % Abstract: % Abstract gives a brief summary of the main points of a paper: \section*{Abstract} Your text here... % Lists: \setcounter{tocdepth}{2} % depth of the table of contents (for Seminars 2 is recommented) \tableofcontents \pagenumbering{arabic} \clearpage %%%%%%%%%%%%%%%%%%%%%%%%%%%% % Content: % the actual content, usually separated over a number of sections % each section is assigned a label, in order to be able to put a % crossreference to it \section{Introduction} \label{sec:introduction} Autonomous robots need to adapt to new situations. They have a need to learn for an entire life. In order to do this they need a second environmental feedback loop that tells them when to learn.\cite{Toutounji2016} The learning poses another problem as well. The previously learned weights are usually largely forgotten, which is known as catastrophic forgetting.\cite{French1999} Since catastrophic forgetting is a key problem for autonomous learning, it is crucial to overcome it. In this paper I will present some approaches for learning in an autonomous setup to analyse which of them if any can overcome catastrophic forgetting. Attempts to overcome that were made by Kirkpatrick\cite{Kirkpatrick2017}, Velez\cite{Velez2017} and Shmelkov\cite{Shmelkov2017}. \section{Neuromodulation} \label{sec:neuromodulation} Neuromodulation is a way to implement the second environmental feedback loop. A Modulated Neural Network (MNN) contains neuromodulator cells (NMC), which are attached to carrier neurons with a modulatory subnetwork (MSN). Neuromodulation can also be done based upon Diffusion. \section{Plasticity} \label{sec:plasticity} Plasticity can be realized by various approaches. Here three approaches are presented, Modulated Random Search, Modulated Gaussian Walk and Diffusion based neuromodulation. \subsection{Modulated Random Search} \label{subsec:mrs} Does things. \subsection{Modulated Gaussian Walk} \label{subsec:mgw} Does things more efficient. \subsection{Localized learning} \label{subsec:diffusion} Velez describe another approach that employs modularity for the learning. Essentially this results in task-specific localized learning and functional modules for each subtask. \section{Comparison regarding catastrophic forgetting} \label{sec:comparison} Modulated Random Search is not at all useful for overcoming catastrophic forgetting. Modulated Gaussian Walk improves to that end. Localized learning overcomes catastrophic forgetting for small networks. \section{Conclusion} \label{sec:concl} A second environmental feedback loop is important to tell autonomous systems when to learn. But the method to learn is important as well to be any use in a practical environment. A comparison has shown that localized learning can overcome catastrophic forgetting for small networks. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % hier werden - zum Ende des Textes - die bibliographischen Referenzen % eingebunden % % Insbesondere stehen die eigentlichen Informationen in der Datei % ``bib.bib'' % \newpage \printbibliography \addcontentsline{toc}{section}{Bibliography}% Add to the TOC \end{document}