Informationssystem och databasteknik, 2I-1033 Processer Processmodeller System.

Informationssystem och databasteknik, 2I-1033

ProcesserProcessmodeller System

Definition of Business Process

A set of activities that takes one or more types of inputs and turns them into an output of greater value to the customer.

[Hammer]

input

input

output

Definition of Business Process

A specific ordering of work activities across time and place, with a beginning, an end, and clearly-defined inputs and outputs; a structure for action.

[Davenport]

outputinput

input

Why focusing on Business Processes?

• discover and adopt to changed customer demands

• automate the activities in business processes

• re-engineering the business processes to make them more effective/efficient

• to specify the requirements on IS

Order register

Add to order

Check order lineStop orderCredit check

Ship

* for each order line

OKi lager

notOK

Credit manager Order manager

A Workflow/Business Process model

Order register

Add to order

Check order lineStop orderCredit check

Ship

* for each order line

OKi lager

notOK

Credit manager Order manager

A Workflow/Business Process model

Task

Resource

Selection(OR split)

Parallelism(AND split)

Basic Workflow Concepts

• Task - a logical unit of work that is carried out as a single whole

• Resource - a person or a machine that can perform specific tasks

• Activity - the performance of a task by a resource

• Case - a sequence of activities performed to achieve some goal, an

order, an insurance claim, a car assembly (“ärende”)

• Work item - the combination of a case and a task that is just to be

carried out

• Process - describes how a particular category of cases shall be managed

• Control flow construct - sequence, selection, iteration, parallelisation

More Concepts

A time point is an instant in time, not further decomposible

An event is an noteworthy occurence

A state shows the condition of a process and can be represented in several way, e.g. as a set of attribute values

Problem: Different meaning of basic terms or not well-defined semantics

Time points Time points

Even

t

Even

tActivityActivity

State State State StateState State

Two examples (there are more):

What are Petri nets?

Petri nets are a method (process modelling language/technique) for describing and analysing processes Petri nets are an abstract, formal method, which means that two totally different processes can have the same structure but different meaning.

Why Petri nets?

Petri nets can be described graphically. Despite that, they also have a strong formal basis. Thanks to this formal basis, it is often possible to verify the correctness of the processes. Petri nets can be used to model computer hardware, software, workflow/business processes and information flow.

Why Petri nets?

Petri nets have available analysis techniques and tools to verify the correctness of the processes

For example, Petri nets can be used to verify software. A program can be converted into a Petri net. The Petri net can then be analysed to find out design errors.

Petri nets can give process modelling languges (like UML activity diagrams) a formal semantics

Application Process

applicationsunder

consideration

ready1

checkvalidity

accept

reject

tokens transition place

preparereject letter

prepareaccept letter

sendreject

sendaccept

ready2

Application Process

applicationsunder

consideration

ready1

checkvalidity

accept

reject

When a transition fires it removes one token from each input place andadds one token to each output place



sendreject

sendaccept

ready2

A transition is enabled (“loaded) when there is a token in each of its input places.

When a transition is enabled it can fire

Application Process

applicationsunder

consideration

ready1

checkvalidity

accept

reject




sendreject

sendaccept

ready2

A transition is enabled (“loaded) when there is a token in each of its input places


Application Process

applicationsunder

consideration

ready1

checkvalidity

accept

reject

tokens transition place




sendreject

sendaccept

ready2


Application Process

applicationsunder

consideration

ready1

checkvalidity

accept

reject




sendreject

sendaccept

ready2

A transition is enabled (“loaded) when there is a token in each of its input places


Enabled Transition

A transition isenabled (“loaded”) whenthere is a tokenin each of itsinput places

Not enabled Enabled

When a transition fires...

When a transition occurs, the transition “fires”, and the transition removes (“consumes”) one token from each input place andadds (“produces”) one token to each output place

Enabled

Input places

Output place

When a transition fires …

When a transition “fires”, the Petri net change state, i.e. a new distribution of tokens.

Fired

What can Petri nets concepts represent?

Place - usually represents a condition, a substate, a geographical location

Transition - usually represents an event, an activity, a transformation

Tokens - usually represent (physical or information) objects, e.g. an insurance claim, an order, a resource (machine, a wheel), a case (“ett ärende”)

What can Petri nets concepts represent?

wheel

engine

chassis

production order/case

car

Dutch Traffic Light

red

yellow

green

yr

rg

gy

Two Traffic Lights

red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

Using a place “free”

If we, for some reason, wish to limit the number of “cases”, which can be under consideration at the same time to n, we can modify the Petri net by using an additional place “free”, and put n tokens in it.

free

Control flow constructs(in a workflow)

AND SPLIT

OR SPLIT

AND JOIN

OR JOIN

High-level Petri nets

Classic Petri nets

High-level Petri nets- the colour extension- the time extension

vs.

Coloured Petri Nets

claims

underconsideration

ready1

checkvalidity

accept

rejectprepare

reject letter


sendreject

sendaccept

ready2

[name: John Doe, amount: 5000]

[name: Mary Doe, amount: 400]

amount < 1000

amount > 1000

In a classical Petri net, tokens have no structure.In a coloured Petri net, each token isassociated with a data structure.

Coloured Petri Nets

claims

underconsideration

ready1

checkvalidity

accept

rejectprepare

reject letter


sendreject

sendaccept

ready2



amount < 1000

amount > 1000

Coloured Petri Nets

claims

underconsideration

ready1

checkvalidity

accept

rejectprepare

reject letter


sendreject

sendaccept

ready2



amount < 1000

amount > 1000

In a coloured Petri net, the valuesof a token’s data structure can be usedin preconditions that determine whichtransition that will fire.

Coloured Petri Nets

claims

underconsideration

ready1

checkvalidity

accept

rejectprepare

reject letter


sendreject

sendaccept

ready2



amount < 1000

amount > 1000

Petri Net with Time

Every token gets a timestamp,indicating the time from which thetoken is available.

A transition is enabled when eachtoken to be consumed has a timestampequal or prior to the current time.

Each transition can give a delay to a tokenproduced by the transition.

Tokens are consumed on FIFO (first-in, first-out basis). The token with the earliest timstamp is the first to be consumed

15 20

10

Petri Net with Time

15 20

10

Before current time = 20, the transition is not enabled and cannot fire.At current time = 20, it will fire. The timestamp of the produced tokenequals the current time + the transition delay (=10 in the example)

10

30

Two Traffic Lights with Time

red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

30 30

55

25 25

0 0

0

0

0

Current time = 0


red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

30 30

55

25 25

0 0

0

Current time = 0 (after the transition)

25


red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

30 30

55

25 25

0 0

0


30


red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

30 30

55

25 25

0 0

0


60

30


red1

yellow1

green1

yr1

rg1

gy1

red2

yellow2

green2

yr2

rg2

gy2

30 30

55

25 25

0 0

Current time = 30 (after two transitions)

60

55

Swimming School Exercise

A student registers at the swimming school. The student willtake one or more swimming lessons followed by an examination.Every lesson has a beginning and an end. A student must have his or her individual teacher during a lesson. There are five teachers. Each swimming lesson is followed by another swimming lesson or an individual examination.An examiner is present at the examination, from beginning to end. There are two examiners. When a student has completed an examination, three things might happen:1. The student passes and leaves the school2. The student fails, takes additional lessons, and tries again3. The student fails and gives up

a) Model this using a classical Petri netb) Use a coloured Petri net to express that it is required to take 10 lessons before taking the exam and that students drop out after three failed examsc) Add time to model that a lesson takes one hour and an exam 30 min.


register

begin lesson end lesson

Free teachers

more

ready

begin exam

end exam

passdrop out

Free examiners


register


Free teachers

more

ready

begin exam

end exam

passdrop out

Free examiners

noOfLessons < 10

noOfLessons = 1060

30

Basic Workflow Concepts

• Task - a logical unit of work that is carried out as a single whole

• Resource - a person or a machine that can perform specific tasks

• Activity - the performance of a task by a a resource

• Case - a sequence of activities performed to achieve some goal, an

order, an insurance claim, a car assembly

• Work item - the combination of a case and a task that is just to be

carried out

• Process - describes how a particular category of cases shall be managed

• Control flow construct - sequence, selection, iteration, parallelisation

Workflow Concepts in Petri Nets

• Task - transition

• Resource - token

• Activity - transition that fires

• Case - token

• Work item - enabled transition

• Process - Petri net

• Control flow construct - modelled by places and transitions


register


Free teachers

more

ready

begin exam

end exam

passdrop out

Free examiners

ResourceTask

Work itemCase

Triggers

When do transitions fire?Sometimes, someone or something has to fire them.

A work item can only be transformedinto an activity once it has beentriggered.

Kinds of triggers

A resource initiative

An external event

A time signal

Triggers

receive order ask for customerinfo

customeranswer

no answer

manage

cancel

Klassifikation av informationssystem

BeslutstypVilka typer av beslut som systemet stödjer Strategiska Taktiska Operationella

FunktionerVilken funktion i organisationen som systemet stöder Marknadsföring Tillverkning och

tjänster Ekonomi Personal

Typer av beslutsstödssystem

TransactionProcessingSystems (TPS)

ManagementInformationSystems (MIS)

IntelligentSupportSystems (ISS)

INFORMATIONS-BEHOV

Alla dessa system stödjerbesluts-fattande

TPS - system som hanterar och lagrar transaktioner

Mata in data

Step 1

Validera data

Step 2

Bearbetadata

Step 3

Transaktion: ett utbyte mellan två parter• Uttag från bankkonto• Förfrågan om pris på en produkt• Beställning av en vara

Hur ett TPS hanterar en transaktion

Lagra data

Step 2

Note: TPS are also called OLTP (Online Transaction processing)

MIS - system som bevakar den interna verksamheten

Sammanfattningsrapport - aggregerar data från många transaktioner och presenterar dem i ett koncist format Månatlig försäljning Årlig personalomsättning

Avvikelserapport - beskriver avvikelser mellan prognos och faktiskt utfall Budgetöverskridande Försäljningsminskning

ISS - Intelligenta StödSystem

ISS - system som stödjer ledningen på högre nivåer att fatta beslut om ostrukturerade problem Decision Support Systems (DSS) Executive Information Systems (EIS) (DSS + MIS)

OLAP (Online analytical processing) (Business Intelligence systems (BI))

ISS - Intelligenta StödSystem

- snabba svar på komplexa, ostrukturerade (ad hoc) frågor

- interaktivitet som gör att beslutsfattare kan utforska olika alternativ

- använder oftast extern och intern data- DSS använder analytiska

beslutsmodeller- grafisk presentation

ISS: ger stöd för komplexa beslut

Samband mellan TPS, MISoch ISS

TPS: hanterar transaktioner

Omvärlds-bevakning

MIS: genererar rap-porter om företaget

Operationell

Taktisk

Strategisk

Organisatoriska funktioner

En funktion är en enhet inom en organisation som utför ett antal relaterade aktiviteter. Vanligen kräver dessa aktiviteter en viss kompetens eller specifik utrustning.

Funktioner på ettuniversitet

Vakt-Vakt-mästerimästeri

KursKursregistreringregistrering

UndervisningUndervisningSystemSystemadministrationadministration

IS för marknadsföring

System som stödjer försäljning, marknadsföringskampanjer, marknadsanalys, m.m. CRM (Customer Relationship

Management) System för försäljningsanalys

IS för tillverkning och tjänster

System som stöder, lagerhantering, produktionsplanering, kvalitetskontroll m.m. Logistiksystem Materialförsörjningssystem

IS för ekonomi

System som tillhandahåller finansiell information som underlag för beslut Intern och extern redovisning Ordermottagning Fakturering

IS för personaladministration

System som stöder planering, samordning, administration och ledning av personal (Human resource systems) Lönesystem Kompetensdatabas

Vakt-Vakt-mästerimästeri

KursKursregistreringregistrering

UndervisningUndervisningSystemSystemadministrationadministration

Processer korsar funktioner

Kurs

Funktioner och IS

FoUFoU MarknadMarknad ProduktionProduktion TjänsterTjänster EkonomiEkonomiPersonalPersonal

Funktioner

Informations-system

Varje informationssystem stödersin egen funktion

Integrerade informationssystem

Order- Order- hanteringhantering

Kund-Kund-tjänstertjänster

Ekonomi-Ekonomi-rapporteringrapportering

FoUFoU MarknadMarknad ProduktionProduktion Tjänster Tjänster PersonalPersonal

Produkt- Produkt- utvecklingutveckling

Ekonomi

Informationssystem och databasteknik, 2I-1033 Processer Processmodeller System.

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