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Controlling Chaos in Ecology: From Deterministic to Individual-based Models

R SOLE
1999 Bulletin of Mathematical Biology  
The possibility of chaos control in biological systems has been stimulated by recent advances in the study of heart and brain tissue dynamics.  ...  More recently, some authors have conjectured that such a method might be applied to population dynamics and even play a nontrivial evolutionary role in ecology.  ...  In the first return map the sensitivity of the system to the control feedback is stronger for negative values of γ , giving raise to smaller population sizes by smoothing the single hump of the map return  ... 
doi:10.1006/bulm.1999.0141 pmid:17879875 fatcat:bqadtwtqd5dnddcslmlcktawza

Target-oriented chaos control

Justine Dattani, Jack C.H. Blake, Frank M. Hilker
2011 Physics Letters A  
We propose a simple, intuitive technique that modifies the values of the state variables directly toward a certain target.  ...  Designing intervention methods to control chaotic behavior in dynamical systems remains a challenging problem, in particular for systems that are difficult to access or to measure.  ...  ; and (iii) alternative population maps.  ... 
doi:10.1016/j.physleta.2011.08.066 fatcat:tetiyiajz5cntnsy7n3m2rb25q

An updated perspective on the role of environmental autocorrelation in animal populations

Jake M. Ferguson, Felipe Carvalho, Oscar Murillo-García, Mark L. Taper, José M. Ponciano
2015 Theoretical Ecology  
We then estimated the degree of environmental autocorrelation present in the Global Population Dynamics Database using a robust, model-based approach.  ...  In this study we first discuss how the autocorrelation present in environmental covariates can be reduced through nonlinear interactions or by interactions with multiple limiting resources.  ...  Global Population Dynamics database: http://www3.imperial.ac.uk/cpb/databases/gpdd.  ... 
doi:10.1007/s12080-015-0276-6 pmid:27158281 pmcid:PMC4856168 fatcat:mnhyvwpd65beljnruqabo37eai

Kinetic instabilities in man-made and natural reactors

L.M. Pismen
1980 Chemical Engineering Science  
In ecology, delayed feedback may be caused by interaction of species on different trophic levels.  ...  This model is in line with recent computational work on onset of chaos in arrays Fig 8 . 8 A Poincar; map (a) and the corresponding flow diagram, (b) generating chaotic behavior.  ... 
doi:10.1016/0009-2509(80)80137-0 fatcat:mrqkqshofjfnzkxsyygdpeqcvq

Connectivity and complex systems: learning from a multi-disciplinary perspective

Laura Turnbull, Marc-Thorsten Hütt, Andreas A. Ioannides, Stuart Kininmonth, Ronald Poeppl, Klement Tockner, Louise J. Bracken, Saskia Keesstra, Lichan Liu, Rens Masselink, Anthony J. Parsons
2018 Applied Network Science  
However, any implementation of the concept of connectivity carries with it both ontological and epistemological constraints, which leads us to ask if there is one type or set of approach(es) to connectivity  ...  We evaluate how a connectivity-based approach has generated new understanding of structural-functional relationships that characterise complex systems and propose a 'common toolbox' underpinned by network-based  ...  Identifying systems or networks that have a hump-shaped structure-function relationship could yield important insights into SC-FC feedbacks and threshold dynamics (i.e. reverse changes in FC once a structural  ... 
doi:10.1007/s41109-018-0067-2 pmid:30839779 pmcid:PMC6214298 fatcat:hcznfb3pw5hgbji4mh2l4uz2im

Dynamic field theory of movement preparation

Wolfram Erlhagen, Gregor Schöner
2002 Psychological review  
The model accounts for a sizable body of empirical findings on movement initiation (continuous and graded nature of movement preparation, dependence on the metrics of the task, stimulus uncertainty effect  ...  The task environment is represented by a 2nd class of fields, which preshape the movement parameter representation.  ...  Those discretized dynamics are globally stable, so that the stable state is reached from any initial pattern of activation.  ... 
doi:10.1037//0033-295x.109.3.545 fatcat:chcfaiu42fc2zgsh6ogianhqdu

Dynamic field theory of movement preparation

Wolfram Erlhagen, Gregor Schöner
2002 Psychological review  
The model accounts for a sizable body of empirical findings on movement initiation (continuous and graded nature of movement preparation, dependence on the metrics of the task, stimulus uncertainty effect  ...  The task environment is represented by a 2nd class of fields, which preshape the movement parameter representation.  ...  Those discretized dynamics are globally stable, so that the stable state is reached from any initial pattern of activation.  ... 
doi:10.1037/0033-295x.109.3.545 pmid:12088245 fatcat:gwk4povmtzhktevhrobd5bxlce

Conference program and abstracts. International Biogeography Society 7th Biennial Meeting. 8–12 January 2015, Bayreuth, Germany. Frontiers of Biogeography Vol. 6, suppl. 1. International Biogeography Society, 246 pp

Daniel Gavin, Carl Beierkuhnlein, Stefan Holzheu, Birgit Thies, Karen Faller, Rosemary Gillespie, Joaquín Hortal
2014 Frontiers of Biogeography  
and a global species richness map.  ...  controlling the dynamics of biological communities.  ...  We modelled the scale-dependency of the three parameters biome-wise, as they varied greatly between the biomes. With nonlinear regression and AIC, we compared a set of different function types.  ... 
doi:10.21425/f56525118 fatcat:3puoxcjd4bcublj6adlg2nzczq

CORPORATE CONTRIBUTORS

1988 The Hastings center report  
cortical areas. 200 Todorov, E., Dept. of Cognitive Sciences, University of California, San Diego: A synthesis of local and global methods for optimal feedback control of nonlinear stochastic systems  ...  input with a global reinforcement signal.  ...  Specifically, we build a dynamic spiking network model that learns the relevant transformations of structured HRR representations in a context sensitive manner.  ... 
doi:10.1002/j.1552-146x.1988.tb03932.x fatcat:bkotcyah2ngbfdk4kbx3xnf5v4

African biomes are most sensitive to changes in CO2 under recent and near-future CO2 conditions

Simon Scheiter, Glenn R. Moncrieff, Mirjam Pfeiffer, Steven I. Higgins
2020 Biogeosciences  
Here, we used a dynamic vegetation model, the adaptive Dynamic Global Vegetation Model (aDGVM), to study lags between actual and expected vegetation in Africa under a changing atmospheric CO2 mixing ratio  ...  The speed of ecological processes such as leaf physiology, demography or migration can differ from the speed of changes in environmental conditions.  ...  In simulations with fire, sensitivity of C 4 -dominated biomes is hump-shaped with a peak at ca. 380 ppm.  ... 
doi:10.5194/bg-17-1147-2020 fatcat:pzfl7od5tvc4tnwjfs7egg4o7a

Diffusive coupling of two well-mixed compartments elucidates elementary principles of protein-based pattern formation [article]

Fridtjof Brauns, Jacob Halatek, Erwin Frey
2020 arXiv   pre-print
Thus, the essential dynamics is the redistribution of the globally conserved mass densities between the two compartments.  ...  In general, the nonlinear, spatially coupled models for protein-pattern formation are only accessible to numerical simulations, which has limited insight into the general underlying principles.  ...  A systematic understanding is hard to achieve, in particular if there are multiple protein species with several conformational states involved (complex interaction network).  ... 
arXiv:2010.15095v1 fatcat:vs5vusjo75gsncy5ydksphb32u

Bayesian binary quantile regression for the analysis of Bachelor-to-Master transition

Cristina Mollica, Lea Petrella
2016 Journal of Applied Statistics  
The working group (WG) CMStatistics comprises a number of specialized teams in various research areas of computational and methodological statistics.  ...  over 1150 members and the following specialized teams BM: Bayesian Methodology CODA: Complex data structures and Object Data Analysis CPEP: Component-based methods for Predictive and Exploratory Path modeling  ...  The tracking devices will use a nonlinear state space model.  ... 
doi:10.1080/02664763.2016.1263835 fatcat:l5eyielgxrct7hq5ljqeej5ccy

Tropical montane vegetation dynamics near the upper cloud belt strongly associated with a shifting ITCZ and fire

Shelley D. Crausbay, Patrick H. Martin, Eugene F. Kelly, Matt McGlone
2015 Journal of Ecology  
Habitat distribution models for TMCF and pine forest taxa show that these state changes were strongly associated with position of the ITCZ (cloud forest xR 2 = 0.63; pine forest xR 2 = 0.53), providing  ...  will change independently, with a 'shifting TWI'. 2.  ...  All of the pollen/spore extracts were prepared at the Limnological Research Center, Department of Geology and Geophysics, University of Minnesota-Twin Cities.  ... 
doi:10.1111/1365-2745.12423 fatcat:6umhnwfawra5bpdot5cdyvkpiq

A sequential distance-based approach for imputing missing data: Forward Imputation

Nadia Solaro, Alessandro Barbiero, Giancarlo Manzi, Pier Alda Ferrari
2016 Advances in Data Analysis and Classification  
One interesting way of making these models more flexible is enriching them with a dynamic discrete latent state Markov process in such a way that the parameters can abruptly switch from one value to another  ...  This happens because the smoothed states for the single-source error representation have the same dynamics as the system, while those coming from multiple-error model depend also on an additional forward  ... 
doi:10.1007/s11634-016-0243-0 fatcat:yvrqlgllsbesbnvnzzci2egpl4

Geomorphic evolution of soil texture and organic matter in eroding landscapes

Nan A. Rosenbloom, Scott C. Doney, David S. Schimel
2001 Global Biogeochemical Cycles  
In this paper, we present the Changing Relief and Evolving Ecosystems Project (CREEP), a theoretical, process-response model that focuses on the redistribution of soil texture and soil carbon along a hillslope  ...  Gridded biogeochemical models, which may otherwise overlook landscape heterogeneity, may use CREEP estimates of the areal distribution of soil texture as a basis for parametrically capturing trace gas  ...  Nelson Caine, and Peter Birkeland for their invaluable discussions on soils and soil carbon transport; Shemin Ge, David Zachmann, and Tom Hilinski for their guidance on model numerics, James White and  ... 
doi:10.1029/1999gb001251 fatcat:of6a5ukfxffs7h5ky6iqwlfyxy
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