Introductie Informatica en Informatiekunde/materiaal/workflow

Uit Werkplaats
Ga naar: navigatie, zoeken
III

FAQvaak gestelde vragen


filosofie van de cursus

Basic concepts

concept definition world special cases examples remark
kitchen example example example
product

object
Substances, information, people, or money that are objects of processing reality ingredient, raw product, half product, end product, catalysator spices, flour, pasta, meat, beefsteak, boeuf Stroganoff
instrument

means
A →thing that is used for production reality plant, vehicle, resource gas ring, pan, sieve An instrument can only be used once at any moment. One production step can require several instruments. The same intrument can be necessary for different production steps, in which case conflicts have to be resolved.
production step

activity
takes some products as ingredients (precondition), performs some operation, thereby using some instrments for a certain time, and produces some products (postcondition) reality thread? input: the white of 3 eggs; instrument: food processor; output: whipped eggs the crossing point of a service and a batch
batch a quantity of products moving from production step to production step resulting in one end product reality 1 egg, 50 g flour and 1 dl milk being mixed and becoming a pancake in several production steps orthogonal to service
service the iterative execution of a production step with the same instrument for different batches reality actor, task the cutting of vegetables with the same knife on the same plate for many dishes orthogonal to batch
scenario all production steps that actually happen in a period of time reality Within a scenario, many batches and services can be identified.
recipe The specification of a class of batches that result in a certain product description A recipe for a product. Recipes usually specify partial orders of production steps, where the products of steps are ingredients for other steps.
functionality The specification of a service description the functionality of a service
protocol The specification of an interface between two services that exchange products description A protocol is an agreement about how two services are to be linked operationally, i.e. concerning input/output and place/time (synchronization etc.).
order A bag of pairs (product, due date) description A scenario conforms to an order if it contains a production step that produces the ordered product at the ordered moment.

The story

  • Design and verification of an artefact for production
    • The purpose of many artefacts is the production of products of a certain class.
    • The design of such an artefact is based on recipes for the intended products.
    • The artefact must provide services for all production steps required by all recipes involved.
  • Design of a control
    • Get the recipes for all ordered products
    • Determine a schedule, i.e. a class of scenarios that contain the batches that conform to these recipes and orders and that can be produced by the available services without conflicts
    • Control the services conforming to this schedule.
  • Verification of a control
    • For any order, there is a batch that conforms to that order.
    • For all steps in all such batches there is a service that can perform it.
  • Efficiency
    • All steps should conform to an order.
    • All products should either be ordered or be input for steps that conform to some order.
    • Services should not be idle.