Predicting the dynamic responses of and energy flows in complex systems in the presence of model uncertainty.

How order emerges from noise? How higher complexity arises from lower complexity? For what reason a certain number of open systems start interacting in a coherent way, producing new structures, building up cohesion and new structural boundaries? To answer these questions we need to precise the concepts we use to describe open and complex systems and the basic driving forces of self-organization. We assume that self-organization processes are related to the flow and throughput of Energy and Matter and the production of system-specific Information. These two processes are intimately linked together: Energy and Material flows are the fundamental carriers of signs, which are processed by the internal structure of the system to produce system-specific structural Information (Is). So far, the present theoretical reflections are focused on the emergence of open systems and on the role of Energy Flows and Information in a self-organizing process. Based on the assumption that Energy, Mass and Information are intrinsically linked together and are fundamental aspects of the Universe, we discuss how they might be related to each other and how they are able to produce the emergence of new structures and systems.

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Zero and root loci of disturbed spring–mass systems

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2013.0751 ◽

2014 ◽

Vol 470 (2164) ◽

pp. 20130751 ◽

Cited By ~ 2

Author(s):

Christophe Lecomte

Keyword(s):

Complex Systems ◽

Frequency Domain ◽

Dynamic Responses ◽

Local Disturbance ◽

Broad Category ◽

Analytical Properties ◽

Discrete Values ◽

Atomic Lattices ◽

Elliptical Region

Models consisting of chains of particles that are coupled to their neighbours appear in many applications in physics or engineering, such as in the study of dynamics of mono-atomic and multi-atomic lattices, the resonances of crystals with impurities and the response of damaged bladed discs. Analytical properties of the dynamic responses of such disturbed chains of identical springs and masses are presented, including when damping is present. Several remarkable properties in the location of the resonances (poles) and anti-resonances (zeros) of the displacements in the frequency domain are presented and proved. In particular, it is shown that there exists an elliptical region in the frequency–disturbance magnitude plane from which zeros are excluded and the discrete values of the frequency and disturbance at which double poles occur are identified. A particular focus is on a local disturbance, such as when a spring or damper is modified at or between the first and last masses. It is demonstrated how, notably through normalization, the techniques and results of the paper apply to a broad category of more complex systems in physics, chemistry and engineering.

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Energy Flows in Low-Entropy Complex Systems

Entropy ◽

10.3390/e17127857 ◽

2015 ◽

Vol 17 (12) ◽

pp. 8007-8018 ◽

Cited By ~ 8

Author(s):

Eric Chaisson

Keyword(s):

Complex Systems ◽

Energy Flows ◽

Low Entropy

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Confronting Model Uncertainty in Policy Analysis for Complex Systems: What Policymakers Should Demand

10.18278/jpcs.5.2.11 ◽

2019 ◽

Vol 5 (2) ◽

Author(s):

Paul K. Davis ◽

Steven W. Popper

Keyword(s):

Complex Systems ◽

Policy Analysis ◽

Model Uncertainty

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The Southern Hemisphere Auroral Radar Experiment (SHARE)

Antarctic Science ◽

10.1017/s0954102094000155 ◽

1994 ◽

Vol 6 (1) ◽

pp. 123-124 ◽

Cited By ~ 6

Author(s):

J. R. Dudeney ◽

K. B. Baker ◽

P. H. Stoker ◽

A. D. M. Walker

Keyword(s):

Solar Wind ◽

Electric Fields ◽

Geomagnetic Field ◽

Ionospheric Plasma ◽

Dynamic Responses ◽

Space Environment ◽

Near Earth Space ◽

Energy Flows ◽

Powerful Means ◽

Electric Fields And Currents

The near Earth space environment (known as Geospace) is dominated by the interaction between the solar wind and the geomagnetic field, which creates the magnetosphere. Considerable energy flows from the solar wind into the magnetosphere and ends up in the Earth's upper atmosphere (the thermosphere and ionosphere). The coupling of the geomagnetic field with that of the solar wind (known as the interplanetary magnetic field, or IMF) produces a variety of electro-dynamic responses with signatures such as electric fields and currents in the polar ionospheres. These produce, inter alia, motion of the ionospheric plasma (at altitudes between 100 and 1000kms) which can be monitored from the ground using radar techniques. Analysis of such plasma motion provides a very powerful means of investigating the nature of the interactions taking place at the boundaries between the magnetosphere and the solar wind. To do this effectively requires simultaneous measurements over as large an area (in latitude and longitude) as possible.

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Exponential Self-Organization and Moore’s Law: Measures and Mechanisms

Complexity ◽

10.1155/2017/8170632 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Georgi Yordanov Georgiev ◽

Atanu Chatterjee ◽

Germano Iannacchione

Keyword(s):

Complex Systems ◽

Technological Progress ◽

Self Organization ◽

Logistic Growth ◽

Moore’S Law ◽

Moore's Law ◽

Energy Flows ◽

Physical Essence ◽

Key Features ◽

Self Organizing

The question of how complex systems become more organized and efficient with time is open. Examples are the formation of elementary particles from pure energy, the formation of atoms from particles, the formation of stars and galaxies, and the formation of molecules from atoms, of organisms, and of the society. In this sequence, order appears inside complex systems and randomness (entropy) is expelled to their surroundings. Key features of self-organizing systems are that they are open and they are far away from equilibrium, with increasing energy flows through them. This work searches for global measures of such self-organizing systems, which are predictable and do not depend on the substrate of the system studied. Our results will help to understand the existence of complex systems and mechanisms of self-organization. In part we also provide insights, in this work, about the underlying physical essence of Moore’s law and the multiple logistic growth observed in technological progress.

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Macroorganisation and flexibility of thylakoid membranes

Biochemical Journal ◽

10.1042/bcj20190080 ◽

2019 ◽

Vol 476 (20) ◽

pp. 2981-3018 ◽

Cited By ~ 8

Author(s):

Petar H. Lambrev ◽

Parveen Akhtar

Keyword(s):

Light Harvesting ◽

Current Knowledge ◽

Three Dimensional ◽

Photosynthetic Apparatus ◽

Dynamic Responses ◽

State Transitions ◽

Photochemical Quenching ◽

Light Harvesting Complex ◽

Complex Ii ◽

Light Harvesting Complex Ii

Abstract The light reactions of photosynthesis are hosted and regulated by the chloroplast thylakoid membrane (TM) — the central structural component of the photosynthetic apparatus of plants and algae. The two-dimensional and three-dimensional arrangement of the lipid–protein assemblies, aka macroorganisation, and its dynamic responses to the fluctuating physiological environment, aka flexibility, are the subject of this review. An emphasis is given on the information obtainable by spectroscopic approaches, especially circular dichroism (CD). We briefly summarise the current knowledge of the composition and three-dimensional architecture of the granal TMs in plants and the supramolecular organisation of Photosystem II and light-harvesting complex II therein. We next acquaint the non-specialist reader with the fundamentals of CD spectroscopy, recent advances such as anisotropic CD, and applications for studying the structure and macroorganisation of photosynthetic complexes and membranes. Special attention is given to the structural and functional flexibility of light-harvesting complex II in vitro as revealed by CD and fluorescence spectroscopy. We give an account of the dynamic changes in membrane macroorganisation associated with the light-adaptation of the photosynthetic apparatus and the regulation of the excitation energy flow by state transitions and non-photochemical quenching.

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