Slovak University of Technology

Faculty of Material Science and Technology in Trnava

Modeling and simulation of systems

Input and output rules in Witness

Elementary rules



Pull

– input rule  Components are take from elements which are arranged into list  

Pull from

element1, element2, element3,...

Push – output rule  Components are sent into element of list which is able to accept them 

Push to

element1, element2, element3,...

 Push to Ship  Push to Scrap

Usage of input-output rules for element machine

Input rule Output rule

Elementary rules

 Wait  Components will be waiting until they will not be entered or pushed out of other element  Buffer (capacity)  The buffer with defined capacity is added to input or output workplace (machine)  Buffer (20)

Least

 Least parts  Components/Parts enter or get out from element with the least number of parts/components 

Least parts

element1, element2, element3,...

 Least free  Parts enter or get out from element the least free capacity of parts 

Least free

element1, element2, element3,...

Most

 Most parts  Parts enter or get out from Element with the most number of parts 

Most parts

element3,...

element1, element2,  Most free  Parts enter or get out from element with the most free capacity of parts 

Most free

element1, element2, element3,...

Percent

 Parts enter into or get out from elements on the basis of given percentage probability 

Percent/flow

percent2,...

element1 percent1, element2  Percent/145 buffer1 40, rbuffer2 60

Sequence

 Sequence/wait  Parts enter or get out from several elements (repeatedly). It waits until the condition is fulfilled 

Sequence/wait

element1#(quantity), element2#(quantity),...

 Typical usage - assembly

Sequence

 Sequence/next  Parts get out from or enter into several elements (repeatedly), but when the condition is not fulfilled the next step follows 

Sequence/next

element1#(quantity), element2#(quantity),...

 Typical usage – batch production

Sequence

 Sequence/reset  Parts get out from or enter into several elements (repeatedly). We wait until all the conditions are fulfilled at the same time. If one condition is not fulfilled start is from the beginning 

Sequence/reset

element1#(quantity), element2#(quantity),...

Match / input rule

 Match/any  Chosen are random parts from the list of elements 

Match/any

element1#(quantity), {and/or} element2#(quantity),....

Match – input rule

 Match/attribute  Chosen are those parts which match with specified attribute  Match/attribute name of attribute element1#(quantity), {and/or} element2#(quantity),....

Match – input rule

 Match/condition  Parts are chosen from the element where a condition is fulfilled. Generally an element is used.

 Match/condition X>3 element1#(quantity), {and/or} element2#(quantity),....

Using Match rule with labor

 Match/qualifier element1 with the name of worker using path #(quantity),...

Select

 Parts enter into or get out from the element in the list which serial number gains integer variable  Select on variable element1, element2,...

If clause

 All input and output rules can be conditioned by usage of If clause 

If condition Rule Else Condition endif

If clause

If condition1 Rule Else if condition2 Rule Else Rule endif

Witness

 Producer  Lanner Group Inc. – Great Britain  Dealer  Humusoft s.ro. – Prague, Czech Republic  Main usage  Witness is set for simulation of production, service and logical processes.  It is used for the support of decision of leading workers at solving of organizational, technical and corded problems mainly connected with restructuring and refining of company processes.

Plug-in modules Witness

 Optimizer  Optimize module proposed with the goal to minimize time and effort spent on experimentation with the model. It is possible to find optimal parameters of watched system by usage of modern optimizing methods in the surrounding suitable for the user very quickly.

Plug-in modules Witness

 Miner  The module for “Data Mining“ analysis . It is possible to identify the relations in extensive data complex by usage of unique algorithms. Then it is possible to use the gained rules for judging of systems ´ behaviour. They are also available as foundation for arbitration process.

Plug-in modules Witness

 Virtual reality  Excellent 3D graphics allows work with the real values of elements of watched systems. This module is important when it goes for 3D orientation or subjective 3D projection. Possibility of work with 3D elements created in various CAD a VR applications.

Plug-in modules Witness

 Documentor  Module determined for creation of well arranged documentation of simulation model.

 Witness Visio  Allows to work with simulation models by usage of all means which WITNESS provides in the surrounding of

VISIO

program.