Discussion on Modeling Solar System

1. Discussion on Modeling Solar System • Where did you start at? • Mentally imagined the “abstract” form of the solar system • High level picture of some number of planets “circling” around the sun • Motionless, Static picture • With planets dynamically moving in orbits and different planes • Wondered how to represent this, regardless of the solution. • Wondered what is my “goal” and the main characteristics of the model that I want to satisfy for this assignment because the instructor keeps on mentioning goals. • Wondered when should I start thinking about this problem and when to work on the solution to the problem --- then started working on it when it got close to my mentally set time - - - then it was step 1.

2. Discussion on modeling Solar System • How many different solutions did you think about? • Were these different solutions or new ways to look at the problem? or new ways to represent solutions? • Glad to just have one solution – did not have time to think of alternatives !!! • How did you decide on the solution? • Thought about all kinds of things before settling on the solution and then just kept on refining. • Thought about a part of the representation of the solution in abstract form and started refining; then went up and abstracted another part and thought of how to represent it; then refined some more; etc. • Thought about the high level abstraction; started to think about a single planet and everything about it; thought about relationships among planets; etc.

3. How many different solutions do you think the class would have? • Do you think the difference is just in representation? • Could there be truly different solutions (that is something that is in one model that’s not in the other models)? • Does that mean other models are inaccurate and incomplete? • Does that mean that this model has extra “stuffs” and therefore it is inaccurate? Isn’t there just one “understanding” of the solar system?

4. Was the Requirement Clear ? • How much “Problem” analysis took place? • Did you think about the problem or just assumed you knew? • Did you have any question when you started working on this assignment --- but there was no one to ask? • Did you make any assumptions: • My work is “probably” good enough • Number of planets needs to be right • Don’t need to include the moons • Orbits need to be included • Probably don’t have to worry about orbital speed • If I do need to, I would just use earth days for orbital speed • Don’t need to worry about describing each planet, such as size, surface temperature, distance from sun, etc. • Don’t need to “define” the solar system - - - that’s the problem statement !

5. Assignment 1 – Solar System • Things to consider: • What is the physical Solar System? • Main components • Subcomponents • Attributes of components and subcomponents • Relationships and possible Interactions among components and sub-components • What is the Software Systems that models the physical system? • Main components • Functionalities • Attributes (data the functionalities work on) • Relationships and interactions among these main components • How far do we refine (depth of model/design)? • How should we represent the model/design ?

6. Assignment 1 – Solar System • Some generalization: • In order to model, provide requirements, even understand the requirements, one needs to understand the system that one is modeling or writing about ---- e.g. Solar System • In order to design the software to model the system one needs to understand the “modeled system” as much as possible: (for Requirements and Design) • The physical system • The business system • The biological system • The social system • Design also requires one to understand what are the capabilities and possibilities of the tools that one has (visual, audio, data base, network, languages, etc.)