Madison Chaos and Complex Systems Seminar

Spring 2000 Seminars

All seminars are Tuesday at 12:05 pm in 4274 Chamberlin except as noted.

Short List


January 25, 2000

A Hodgepodge Guide to Symbiotic Evolutionary Dynamics

Ismor Fischer, UW Department of Biostatistics and Medical Informatics

This general talk will explore some ongoing developments in evolutionary biology from the point of view of dynamical systems, specifically the role of symbiosis as a driving force in the emergence of complex adaptive systems in nature (e.g., the Endosymbiotic Theory of Eukaryote Evolution).  Formal models of these self-organized structures include approaches from physics (autocatalytic chemical networks, hypercycles), computer simulation (cellular automata), and mathematics (category theory).  Issues addressed will include the evolutionary arrow of increasing (?) biological complexity, and the resulting inevitability (?) of consciousness and intelligence.  In addition, the talk will be supplemented by fossil specimens of some of the organisms that provided the original impetus for many of these concepts.

February 1, 2000

Self-organization and Family Systems Theories

David Pincus, Marquette University, Department of Clinical Psychology

Family systems theories have developed primarily through clinical practice, separate from empirical research of relationships and small group processes.  This separation has led to the development of a variety of family systems theories which are largely untestable with respect to family processes (as opposed to the more simple question of therapeutic outcome) and to empirical research which often lacks a systemic theoretical framework.  The current presentation will describe a model of human interpersonal dyanamics, the 5-R's model, which may provide a more unified view of small group processes, familial and nonfamilial, which is empirically testable using recent theoretical and methodological advances within nonlinear dynamical systems theory.  The model describes four oblique underlying structures:  rules, roles, relationships, and realities which emerge through principles of self-organization and which are co-determining of familial response patterns (the 5th R).  A pilot test was conducted using orbital-decomposition (Guastello, in Press) to analyze a brief family problem-solving discussion for Shannon's entropy, topological entropy, and deterministic recurrence patterns.  The results will be discussed in relation to family therapy and to the 5-R's model.

February 8, 2000

Self-Organized Chaos in Plasmas: From the Laboratory to Space

Stewart C. Prager, UW Department of Physics

A plasma is a gas of charged particles.  Most of everything beyond the Earth's environment is in the plasma state, and numerous laboratory investigations of fundamental plasma behavior are underway. Since each particle in a plasma interacts simultaneously with every other particle in the plasma, a vast array of collective and complex behavior is exhibited.  In this talk, we will focus on the tendency of plasmas to rearrange and spontaneously generate magnetic field, and for the magnetic field to become chaotic. Despite the complexity of a plasma, magnetic field generation and chaos can be understood from simple principles.  These phenomena are relevant for understanding diverse situations - from the generation of magnetic field in stars and the Earth to the confinement of energy in fusion energy systems.

February 15, 2000

Unraveling the Turbulent Nature of Day-to-Day Weather

John Young, UW Department of Atmospheric and Oceanic Sciences

The wind patterns that characterize our mid-latitude weather over days and weeks are interesting not only in our physical world, but also in the spectral world representing their scales of space and time variability. In this talk, I will attempt to illustrate these two views of real weather variability and explain some basics of the  nonlinear mechanics producing these chaotic flow patterns.

Observations will introduce the topic, in the form of both animated global flows and spectra describing their space-time scale characteristics. The energy exchanges between different scales will be described in terms of triad interactions between wave patterns. These interactions, and the related phenomena of short term wave cycles and longer-term vortex mergers, help give insight into E.N. Lorenz's time limits to a successful prediction.

February 22, 2000

Impact of Building Multiple Protective Factors in Family Systems of Children at Risk for Mental Health Problems

Lynn McDonald, Education- WCER--Wisconsin Center for Education Research

An early intervention multi-family group approach in which a collaborative team applies parent-mediated play therapy, couple interactive time, self-help parent group time, and family-based activities, will be presented.  This systemic approach, called FAST (Families and Schools Together), has been replicated in over 110 school districts in Wisconsin and in 35 states and 5 countries.  The approach is interpersonal, positive, and interactive with several sub-groupings of 8-10 previously isolated families from the same elementary school over eight weeks.  The focus of outcome measurement has been on the social and emotional functioning of the child at-risk for problems. The program founder will discuss the unanticipated effects on adult participants.

February 29, 2000

Constructing Meaning: The Role of Affordances and Grammatical Constructions in Sentence Comprehension

Art Glenberg, UW Department of Psychology

This talk presents a new theory of language comprehension and meaning as well as data that support the theory.  Standard views of language are based on the assumption that meaning arises from the syntactic manipulation of abstract symbols.  I will demonstrate in several ways that this assumption is incorrect.  The new theory grounds meaning in action and describes how abstract symbols (i.e., words) become meaningful ideas.

March 7, 2000

Height Functions and Nonlinear Recurrence Relations

Eric Bach, UW Department of Computer Sciences

Sequences defined by nonlinear recurrence relations arise naturally in certain counting problems, and for this reason are important in discrete mathematics and computer science.  In this talk I will explain how the theory of height functions, a device invented for the study of diophantine equations, can be used to elucidate the asymptotic behavior of such sequences.

March 21, 2000

Spectra and Phases of Seafloor Roughness: Phenomenology and Simulations

Clarence S. Clay, UW Department of Geology and Geophysics

The wave number" power law" spectra of seafloor topography is well established.  The power spectrum is proportional to s^(-beta), where s is 1/(wavelength).   Most of these results were obtained using the finite Fourier transformations (fft).  The phases of the components of frequency are generally assumed to be random but are not displayed.  Some researchers pad the profile (after removing the mean) with zeros and some do not.

Another method of analysis determines the dependence of the standard deviation of a profile on the length of a section L selected for analysis.  If beta is greater than 1, then the standard deviation depends on L and has a "power law" dependence on L, L^(beta-1)/2.

Since classical time series analysis starts with a finite set of data and then uses the infinite Fourier integral,  numerical approximations to the infinite Fourier integrals are used here to avoid the zero padding issue.  In addition, a phenomenological analysis of the phases and amplitudes of an echo sounder profile of the seafloor is in order.

A reviewer questioned the association of random interfaces and slowly varying phases so a review of a simple random process is included.  There are as many ways to construct random functions and their phases as there ways to lose money in casinos.  The classic coin toss game from Feller (1950 and 1957) illustrates a interesting example of the slow variations a gambler's winnings in a simple game and how a random function can be slowly varying.  The phases of the frequency transformations of a real profile and simulations have the same appearance.

March 28, 2000

Numerical Simulation of Nonlinear Atmospheric Flow Systems

Greg Tripoli, UW Department of Atmospheric and Oceanic Sciences

Large increases in computer power over the last two decades have allowed for the numerical simulation of highly nonlinear atmospheric flows. Coherent structures often evolve within these turbulent flows that may resemble observed structures in the real atmosphere. Despite their realistic appearance, however, the simulated structures can arise from systematic biases in numerical truncation error.  In this seminar, I will present some results of our efforts to simulate the cloud and eddy structure over Lake Michigan and show evidence to this effect. Approaches designed to lessen or alleviate these biases involving the use of integral constraints on the numerical system will be discussed and results of these approaches presented.

April 11, 2000

How is Chaos  and Turbulence Measured in Experimental Plasmas?

Stewart C. Prager, UW Department of Physics

Plasmas generate chaos and turbulence, which in turn drives the plasma into a self-organized state.  In a previous seminar, we discussed the physics of how the plasma spontaneously generates magnetic field, and how the magnetic field becomes chaotic.  In this seminar we discuss how we actually measure and control the chaos in experiment.  The challenge is to measure the detailed spatial structure of magnetic field, plasma flow, temperature and other quantities inside a plasma at a temperature of 5 Million degrees.  As part of the seminar we will tour the MST experimental facility in Chamberlin Hall.

April 18, 2000

Complex Dynamic Phenomena when Making Polymers

W. Harmon Ray, UW Department of Chemical Engineering

An understanding of the dynamic behavior of polymerization processes is a necessary precursor to the design of reliable control systems and the ability to achieve reproducible, high quality polymer product in an efficient process. In addition, this understanding is essential for the prevention of runaway episodes which can endanger human lives and result in environmental pollution. Both computational and experimental examples will be presented showing that multiple steady states, multiple periodic solutions, limit cycle oscillations, and more complex dynamics leading to chaos can arise in industrial polymerization reactors.

April 25, 2000

The Utility of a Nonlinear Model of Everyday Problems

Teresa Hayden, UW Department of Psychology

Psychological problems are conceptualized as cyclical patterns of thoughts/behaviors/emotions which repeat over time.  This model is proposed to be useful for training psychotherapists, and for ordinary people to better understand and change themselves.

Undergraduate students, most of whom eventually plan careers in psychotherapy, learned this model, then responded to questions about its ease of application to their own lives and to the lives of others.

This talk will briefly review the model, then discuss how it was taught and its utility for these students.

May 2, 2000

Introduction of WCSAR Research Program

Weijia Zhou, Wisconsin Center for Space Automation & Robotics

The Wisconsin Center for Space Automation and Robotics (WCSAR), founded in 1986 and located at the University of Wisconsin-Madison, is a NASA-cosponsored Commercial Space Center (CSC) with a mission to support industry in the development and commercialization of new technologies derived from applied research conducted in microgravity, thereby contributing to improved quality of life on Earth and to a long-term human presence in space.  Since 1986, WCSAR has developed a variety of innovative robotic and automated technologies to support eight commercial plant biotech experiments on board the Space Shuttle and the MIR Space Station. In addition to that, WCSAR is actively engaged in development of controlled environment technology for commercial applications.  Patented controlled environment technologies include LED light unit, ASTROPORE humidity control unit, and non-consumable ethylene scrubber.   These technologies provided the basis for development of the space-based plant research facilities, including ASTROCULTURE (ASC), Advanced ASTROCULTURE (ADVASC), and Commercial Plant Biotechnology Facility (CPBF).