I. Systems and system theory --
A. System: a structured set of units
with common properties and the ability to interact and to operate as a
complex whole.
The conditions or state of any
part of the system is dependent on the state of entire system.
B. Types of systems and examples
1. Isolated, Closed and Open
2. Examples --
human body, stream erosion, test tube
C. System descriptors -- components,
process, inputs, outputs
D. Observing the system -- Variables
E. Steady State
1. Homeostasis -- essential variables
F. Stability -- effects of perturbations or stress.
G. Dynamic Equilibrium
1.Le Chatelier's Principle
H. Feedback -- system communication
1. Positive and negative feedback
2. Tight and loose – effect of response time
3. Examples -- Body temperature; Ice, albedo and temperature;
Predator and prey; Pressure and volume; Jobs and economic growth
II. Flow Charts -- visual representation of process
A. Connections between variables and
process
1. Human (Temperature Control)
2. Climate system (Temperature control)
B. Recognizing feedback in flow charts
C. Open and closed systems – the effect on relationships within the
system
1. Energy flow
2. Material flow
III. Graphical analysis
A. Trends and limits
1. Time Series -- an important
tool for presenting system behavior – measured or predicted
B. Recognizing steady states
C. Identifying stable and unstable systems
IV. An example -- Global temperature control
A. Planetary temperature
1. Input and output
2. Geologic record
3. Can biological systems act to control planet temp?
B. Daisy World -- a model system
1. Conditions
2. Analysis
Objectives:
1. Use systems analysis to describe common systems like a family, the
solar system, an atom, a star, beer production
2. Give examples of closed, open and isolated systems and discuss the
differences between them.
3. Discuss the effects of stress on steady state systems. Use examples
to demonstrate the relationship of stress and steady state stability.
4. Describe evaporation and condensation of water in a closed system in
terms of Le Chatelier's principle. Provide a similar description for
sugar dissolving in water.
5. Describe feedback in several simple systems. Relate the nature of
feedback to the stability of the system.
6. Use the example of stellar size, gravitational attraction and
internal pressure to describe a stable steady state. But show how size
and gravitation alone predict a possible unstable steady state and
system.
7. Draw a flow chart showing the movement of energy through the earth
system. Verbally describe energy input and output in the earth system.