Self-Organization Wiki - User contributions [en]

Visualization Tools

2013-09-12T09:27:13Z

Ifeherva: /* Box plot */

== Box plot ==

A box plot is a good way to depict results where measurements have been taken over another parameter, for example the fitness of several independent runs of an evolutionary algorithm over the number of generations.

=== Box plots with R ===

The statistic software R can be installed quickly, e.g., on Debian/Ubuntu Linux by "apt-get install r-base".
The data must be given in a tab-seperated file, where each column comprises the measurements for one box.

x <- read.table("datafilename.tsv")
postscript("outputfilename.ps")
boxplot(x)
dev.off()

The postscript command redirects the output to a postscript file. The last command flushes the output and closes the file.

=== Data manipulation with R ===

Sometimes it is necessary to postprocess data before plotting it.

x <- read.table("datafilename.tsv")

storing every nth column with n=3

y <- x[seq(1,ncol(x),3)]

storing every nth line with n=3, starting from first.

z <- x[(seq(1,nrow(x),3)), ]

=== Example script that selects every 6th column for data and plots it into a pdf file ===

y <- read.table("rboxplot.txt", col.names = seq(1,500,5), check.names=F)
z <- y[(seq(1,nrow(y),6)), ]
a <- z[seq(1,ncol(z),3)]
pdf("boxplot_fitness.pdf")
boxplot(a, xlab="Generation", ylab="Fitness")
dev.off()

Design Patterns for engineering SOS

2010-07-13T09:59:27Z

Ifeherva: /* Design Patterns for SOS? */

== Design Patterns for SOS? ==
* The idea of reuse existing, proven solutions seems to be interesting, but...
* Focus on mechanisms that cause systems to be SOS
* Use a pattern at design time, so that a SOS runtime behaviour shows up
* The usage of design patterns depends on the nature of the desired system
** Categorize types of SOS and assign possible design patterns, which are useful for which type
* Checklist seems currently to be more appropriate, we know what is necessary to get SOS
** Checklist for basic properties of SOS: Adaptivity, Emergence, Autonomy, Decentralisation, Cognition, Feedback, Multiple intercations
* Runtime effects to show up: spatial temporal structures, multiple stability, parameter bifurcation

== Design Patterns ==
* Achitectural patterns
** Observer-Controller Architecture (Organic Computing)
** MAPE (Monitor, Analyze, Process, Execute) Cycle (IBM Autonomic Computing)
* Patterns for (interaction) mechanisms
** Artificial Hormone System (moving/placing resources/load balancing)
** Ant foraging (reliably find shortest routes)
** Pulse-coupled oscillators
** Plain diffusion, replication, chemotaxis, and stigmergy, …

* Patterns of coordination
** Stigmergy
** Combine positive/negative Feedback w. Balance
* Control Theory -> Feedback loop
* Coupling between local interactions and global behaviour

== Related Work on Design Patterns ==

In software engineering: ''a design pattern is a general reusable solution to a commonly occurring problem in software design. A design pattern is not a finished design that can be transformed directly into code. It is a description or template for how to solve a problem that can be used in many different situations'' [http://en.wikipedia.org/wiki/Design_pattern_%28computer_science%29]
* Design Patterns for Self-organising Systems, Gardelli et al.
* Design Patterns from Biology for Distributed Computing, Babaoglu et al.
* Design patterns for decentralised coordination in self-organising, De Wolf et al.

Robustness

2009-06-24T08:56:55Z

Ifeherva: /* Robustness as a Design Problem */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If it is difficult to see the connection between the local behavior and the emergent property then how can one draw conclusions and update the system?

Q: Does the design method for SOS play a role for robustness or not?

A: It is important to clearly define the terms "self-organization" and "robustness" to be able to answer the question

==Internal Robustness==

There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Robustness

2009-06-24T08:46:46Z

Ifeherva: /* Robustness as a Design Problem */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

Q: Does the design method for SOS play a role for robustness or not?

A: It is important to clearly define the terms "self-organization" and "robustness" to be able to answer the question

==Internal Robustness==

There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Robustness

2009-06-24T08:46:31Z

Ifeherva: /* Robustness as a Design Problem */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

Q: Does the design method for SOS play a role for robustness or not?
A: It is important to clearly define the terms "self-organization" and "robustness" to be able to answer the question

==Internal Robustness==

There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Robustness

2009-06-24T08:44:51Z

Ifeherva: /* Robustness as a Design Problem */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

Does the design method for SOS play a role for robustness or not?

==Internal Robustness==

There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Adaptation

2009-06-24T08:18:22Z

Ifeherva:

==Definition of adaptation==

*When can we say that a system is adaptive?
*When can we say that a component is adaptive?

==Adaptation of a component==

If we consider it as a black box is it important to distinguish the system-in-the-box between a fully adaptive (eg. knowledge-based) solution or a hard-coded one (like an EPROM)? The following two terms should be introduced: adaptive behavior and adaptive methodology clearly separating the component's behavior (external) and the workflows inside (internal).

Adaptation

2009-06-24T08:15:25Z

Ifeherva: New page: During the corresponding discussion the focus turned to the term adaptibility in this context. When can we say that a component is adaptive? If we consider it as a black box is it importan...

During the corresponding discussion the focus turned to the term adaptibility in this context. When can we say that a component is adaptive? If we consider it as a black box is it important to distinguish the system in the box between a fully adaptive (eg. knowledge-based) solution or a hard-coded one (like an EPROM)? As an answer the following two terms have been introduced: adaptive behavior and adaptive methodology clearly separating the component's behavior (external) and the workflows inside (internal).

Robustness

2009-06-23T13:56:39Z

Ifeherva: /* Internal Robustness */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

==Internal Robustness==

There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Robustness

2009-06-23T13:56:19Z

Ifeherva: /* Internal Robustness */

== Definition of Robustness ==

* Robustness
** Is there a common definition (which is valid for all research areas)?
** Should there be a definition of robustness?

The adjacent discussion delivered the following: Robustness is a term which has to be specified for every single case. The reason is simply that a system can only be robust against certain disturbances but not against all. Hence, a common definition does not exist.

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

==Internal Robustness==

[Please explain the term]
There are several ways for designing SOS based on trial-and-error methods, by deriving local rules from model system with extra knowledge or using some intelligent search. However without proper validation and testing there could be a possibility where the emerged behavior shows unanticipated phenomenas.

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

== Robustness in control theory ==

The research area of control theory seems to us as a classical field where the definitions cannot be brought inline with the theory in this field. For instance, we have a certain system which we would like to control. Robustness in this case means that we would like to adapt to certain disturbances. In order to notice these disturbances, there has to be a kind of feedback loop which allows for reacting on unintended changes in the output of the system. These reactions on unintended changes are carried out by a so-called controller which will feed inputs to the system which has to be controlled. However, this controller can be seen as a centralized unit handling all disturbances. It is thus not clear, if such an approach can be still regarded as a self-organizing system. More in detail, it will either depend on the point of view, from which someone is looking at the system, or on the definition used to characterize a self-organizing system (see Definition_of_Self-Organizing_Systems). For instance, using definition (3), the described system would still fit into the context of a self-organizing system, whereas it would not, if definition (1) is used as reference.

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Main Page

2009-06-23T12:26:05Z

Ifeherva:

== A Wiki on Self-Organizing Networked Systems ==

* [[Definition of Self-Organizing Systems]]
* [[Misconceptions]]
* [[Self-Organization being a Discipline on its own?]]
* [[Robustness]]

=== Resources ===

* [[Self-Organizing Systems Research Groups]]
* [[Self-Organizing Systems Conferences]]

== Lakeside Research Days ==

* [[Lakeside Research Days|Lakeside Research Days General Information]]
* [[Lakeside Research Days'08]]
* [[Lakeside Research Days'09]]

== How to use the Wiki ==

Consult the [http://meta.wikimedia.org/wiki/Help:Contents User's Guide] for information on using the wiki software.

=== Getting started ===

* [http://www.mediawiki.org/wiki/Manual:Configuration_settings Configuration settings list]
* [http://www.mediawiki.org/wiki/Manual:FAQ MediaWiki FAQ]
* [http://lists.wikimedia.org/mailman/listinfo/mediawiki-announce MediaWiki release mailing list]

Robustness

2009-06-23T12:19:50Z

Ifeherva: New page: ==Robustness as a Design Problem== Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavio...

==Robustness as a Design Problem==

Even though the term robustness is also quite loose we realized that it can be often routed back to design problems. Usually, only the emergent behavior can be easily observed and by this, it is not trivial how the system should be changed on its component behavior level to help it to increase its robustness.

If there is little knowledge about the local rules how can the we draw conclusions and update the system? [Elaborate this sentence more, pls.]

==Internal Robustness==

[Please explain the term]
(We also formulated a possible threat where the designed SOS could show not anticipated possibly harmful behaviors due to bad modeling and design approaches. A solution for this would require the definiton of the term internal robustness.)

==System Borders==

As a final thought, we think it is important to define the current borders of the system before we start dealing with its robustness. As a simple example could be a "robust" algorithm which obviously cannot withstand a blackout. In what way is it robust then?

==Research Questions==

* When properties are emergent, how can you make sure that the
emergent situation is following your intentions?
Robustness from within ?

Definition of Self-Organizing Systems

2009-05-27T09:58:53Z

Ifeherva:

==Ad-Hoc Definitions==

=== Definition from Research Days'08 (1) ===

''A selforganizing system (SOS) is a system that uses simple local rules to achieve complex global behavior.''
Additional precodnitions to this definition include:

* ''Multiple units/entities''
* ''Communication among some of the entities''
* ''Adaptive based on external measurements/events''
* ''Observer''
* ''No hard coded solutions by the designer''

=== Definition from Research Days'08 (2) ===

''A self-organizing system (SOS) is a set of entities that obtains global system behavior via local interactions without centralized control.''

=== Definition from Research Days'08 (3) ===

''A system shows self-organizing behavior if it is autonomous, adaptive, and its organization and function is an emergent property.''

=== Definition by Farley and Clark of Lincoln Laboratory in 1954 ===

''A self-organizing system is a system that changes its basic structure as a function of its experience and environment.''

Definition of Self-Organizing Systems

2009-03-10T07:48:30Z

Ifeherva: /* Definition from Research Days'08 (2) */