System principles Flashcards
What does a system consist of?
- Elements
- Interconnections
- A function or purpose
What is most influential of a system?
The purpose, if you change the purpose, the system will behave differently.
What is a stock?
The stock is the foundation of any system. These elements of the system are the ones you can see, feel, count or measure at any given time.
What is a flow?
A flow changes the quantitiy of the stock. It is filling and draining.
A stock is the memory of the history of changing flows within the system
When will a stock rise and when will it fall down?
rise: when inflows exceed outflows
fall: when outflows exceed inflows
When will a stock be in a dynamic equilibrium?
When the sum of outflows equal the sum of inflows
How can a stcok be increased/decreased?
A stock can be increased by increasing the inflow or descrease the outflow.
A stock can be decreased by decrease the inflow or increase the outflow
What does a stock do in a system?
Act as a delay or buffer - A stock changes slowly, even if you increase the inflow/outflow abruptly.
A stock allows inflows/outflows to be de-coupled and independent - The presence of stocks ensures that inflows and outflows are independent of each other
What is a feedback loop?
A closed chain of causal connections from a stock, trhough a set of decisions/laws/actions (variables) that are dependent on the level of the stock and back again through a flow to change the stock
What is a balancing feedback loop?
also called negative feedback loop; A stabilizing, Goal-seeking structure in systems to regulate the feedback loop.
What is reinforcing feedback loop?
A positive feedback loop, a Self-enhancing leading to exponential growth or to a runaway collaps over time. More interest leads to more money in the bank
What is equilibrium?
A stable moment in time; inflow equals outflow - there is no increase or decrease
what is oscillation?
An element of the system moving back and forth and return into its initial state after a certain period of time
What is resillence?
The ability of a system to recover from pertubation
so the ability to restore after a change due to an outside force
What are nonrenewable resources?
The resources are not renewed, this means that the stock is not renemed -> the stock is limited. The faster the extraction rate, the shorter the lifetime of the stock
What are renewable resources?
Resoruces that are inexhaustabile (ontuitputtend) but limited in the amount of resource that available per unit of time. They are flow-limited.
A minor change in the strength of controlling balancing feedback loop can make a big difference
