Systems Flashcards
(43 cards)
Physical System
A system composed of physical parts. Often, it is a portal of the physical universe that will be analyzed
Biological System
A system made up of living organisms or that are present in nature
Sociological System
A system composed of social beings
System Thinking
New problem solving approach to dealing with today’s world of complex problems.
Developed by Professor Jay Forrester of MIT in 1956.
Focuses on how the parts of a system interrelate and how the system behaves over time,
Uses computer based tools as well as various types of graphs and diagrams such as a BOT graph and a CLD diagram.
Provides results that are often counter-intuitive, far reaching, and unforeseeable.
Systems Thinking helps better organize thoughts in ways that have more meaning.
Helps establish connections that otherwise seemed to have had no relation.
Allows individuals to understand how “systems” change over time.
Helps identify what causes systems to change over time.
Aids in communicating results and conclusions.
Systems Thinking provides a mechanism for structured thinking to acknowledge the entire “picture” and arrive to the right course of action
Provides a basis to comprehend non-intuitive results caused by complex Cause & Effect relationships.
Provides deeper insight in understanding how systems behave over time through exercising models such as VENSIM.
- Understand the problem as a system.
- Determine the objectives of the users.
- Define the parts of the system.
- Determine the relationship among the parts.
- Understand the desired behaviors of the system.
- Develop a model that represents the system.
- Explore “What if” scenarios with the model.
- Draw conclusions about what to do.
Systems Boundary
An imaginary line drawn to depict the components/parts within the systems. System boundaries are used to be able to define the structure of the system.
Arbitrary, meaning that they are of personal choice
Linear Growth
Means the something grows in the same amount each time step
Non-linear growth
Means that something grows on diff. amounts each time step
Growth rate
The rate of increase in size per unit time
BOTG- Behavior Over Time Growth
The graph shows how systems behave in different ways as time goes on; this could be a linear or a non-linear behavior. Helps us think more about the reasons why the systems behaves like it is behaving. Time must always be the horizontal axis. The behavior is the variable that changes over time and must be in the vertical axis
Cause and Effect
A relationship in the system where the cause of one action within the system or from its surroundings creates an effect on another parts or parts within system; In any system, an effect cannot occur without a cause. There is always a reason why something occurred. This helps us determine the relationships found within the system.
Feedback loops
A process in which the information obtained from an output/effect is returned to its initial input/cause.
Example: Human Population
Cause and Effect Diagram
Helps create a visual representation of the cause & Effect relationships present in the system.
Uses arrows to connect causes to effects until a final effect is reached, basically the function of the system.
Casual Loop Diagram
A connected cause and effect diagram which could include feedback loops
Stock
Measured at a specific point in time; represents a single quantity at that specific point in time; Stocks are usually represented with nouns; If time is hypothetically stopped, stocks do not disappear; Stocks send out signals to the rest of the system; Stocks have memory: This means that a stock will not increase or decrease in amount when an inflow or outflow is suddenly stopped; Stocks change the time shape of flows: Different time shapes of flows will yield a different stock time shape; Stocks decouple flows: Decoupling flows allows for inflows to be at different rates than outflows. This means that disequilibrium in the system is possible; Stocks create delays: As mentioned before, a delay occurs when the effect of a cause happens at a time way after the cause was initially placed.
Flow
Measured with an interval of time; represents a rate with respect to time; Flows are usually represented with verbs; Flows disappear if time is hypothetically stopped; A flow can be into the stock or out of the stock
Muscular System
- Muscles: have the ability to contract and relax
- Tendons: connect your muscles to your bones and help stabilize joints
- Ultimate function: to help you be able to move. Muscles’s ability to contract and relax, and the tendons connection between muscles, bones, and joints, make movement an easy task for the body
Skeletal System
- Cartilage joins bone to muscle and can act as a shock absorber in joints and bones
- Bones: what make most of the skeletal system, keeping everything together and so giving the form to any body (could be a human or animal body)
- Ultimate function: to keep your form and to manage physical tasks that might need to be performed. The cartilage in the bone joints will act as shock absorber so the damage is almost none
Circulatory System
- Blood: the fluid that carries needed nutrients and oxygen to the whole body so it can work properly, and also takes from cells what needs to be removed
- Veins, arteries, and capillaries: veins and arteries are different tubes that transport the blood throughout the body
- heart: is a special muscle that works as a pump. The heart pumps blood through the arteries, and veins
- Ultimate Function: keeps the whole body getting the nutrients it needs. The heart will pump the blood through the veins and arteries (that are connected by the capillaries) and so every cell will get what it needs and what has to be removed
Human Body System Function
Our body is composed with more than three systems. These systems work together to keep us working by getting each of their parts to function in some way that at the end of the day, we stay healthy
Newton’s 3rd Law of Motion
For every action, there exists an equal and opposite reaction
Attributes
Found in Cause & Effect relationships. Usually, attributes have levels, which are amounts of attributes. Examples: dollars, pounds, number of people. Some attributes have levels per unit time, known as rates. Examples: dollars/hr., pounds/day, people/year
Important Symbols
Each element can have a (+) or (-) sign attached to the “effect” side of the connecting arrow indicating the direction of the “effect” due to a change in the “cause”.
(+): Use when an increase in the “cause” leads to an increase in the “effect”
(-): Use when an increase in the “cause” leads to a decrease in the “effect”
Each Feedback Loop has a net effect, either Balancing (B) or Reinforcing (R).
(B): Use when a balance occurs between the original change and the change it caused. (more gives you less or less gives you more)
(R): Use when there is a growth or decline in the Feedback Loop.
Delays (||) are used when Feedback Loops take time before they come into effect.
System
A system is composed of several parts/things, each with their own specific function, working together to accomplish a purpose only achieved by the combination and interaction of each individual part/thing. A system can also be composed of several other systems, referred to as “subsystems”. These subsystems also have several parts/things working together to accomplish the purpose of the system as a whole.
The Systems Thinking Problem Solving Process
Understand the problem as a system.
Determine the objectives of the users.
Define the parts of the system.
Determine the relationship among the parts.
Understand the desired behaviors of the system.
Develop a model that represents the system.
Explore “What if” scenarios with the model.
Draw conclusions about what to do.
