Politecnico di Milano - Intranet DEIBhome.deib.polimi.it/schreibe/dbmanagementsystems/materiale/pdf/... · executive report systems (eis) ... model flexibility temporal stability

INFORMATION SYSTEMS

Prof. Fabio A. SchreiberDipartimento di Elettronica e Informazione

Politecnico di Milano

Fabio A. Schreiber Information Systems 1

COURSE PROGRAMME (1)

Technical aspects of modern Information Systems (30 hours)

· historical development and classification ofInformation Systems;

· analysis techniques and design methodologies; · view integration; · data/functions integration; · heterogeneous and distributed data bases integration;

the role of telecommunication networks: Internet and intranets

·

data organization for DSS: data warehousing and knowledge discovery;

·


COURSE PROGRAMME (2) RELATIONS AMONG TECHNOLOGICAL ASPECTS

I.S.ANALYSIS

INTEGRATION OF•VIEWS•DATA AND FUNCTIONS

DISTRIBUTEDDATA

MANAGEMENT

DATA WAREHOUSE

DATAMINING

INTRANETAND WWW

INFORMATION RETRIEVALSYSTEMS

WORKFLOWMANAGEMENT

SYSTEMS

DECISION SUPPORT

COOPERATION

MULTIMEDIALAND UNSTRUCTURED

INFORMATION


UNIFYING PROBLEMS

• DISTRIBUTION OF– DATA SOURCES– SERVERS– USERS

• DATA HETEROGENEITY– FORMATS– SEMANTICS

• POOR STRUCTURING OF DATA AND OF INFORMATION


COMMON TECHNIQUES

• INTEGRATION BETWEEN WEB AND DATA BASES

• INTEGRATION BETWEEN WORKFLOW AND DATA BASES

• STATISTICAL METHODS OF DATA ANALYSIS– DATA MINING– WEB AND DATA BANKS SEARCHING


THE ROLE OF THE ITALIAN UNIVERSITIES IN INFORMATION SYSTEMS EDUCATION

• CORSO DI LAUREA IN INGEGNERIA INFORMATICA– TECHNOLOGY AND COMPLEX APPLICATIONS DESIGN

• CORSO DI LAUREA IN INGEGNERIA GESTIONALE– ORGANIZATION AND COMPLEX APPLICATIONS DESIGN

• CORSO DI DIPLOMA IN INGEGNERIA INFORMATICA– TECHNOLOGY AND APPLICATIONS MANAGEMENT– LOW/MEDIUM COMPLEXITY APPLICATIONS DESIGN

• DOTTORATI DI RICERCA (PhD) – INNOVATION DESIGN


INFORMATION SYSTEMS BACKGROUND

INFORMATION SYSTEM

ORGANIZATION

INFORMATIC TECHNOLOGIES AND METHODOLOGIES

STRUCTURE ANDORGANISATION ASPECTS

FUNCTIONAL ANDPLANNING ASPECTS

PROCEDURES DATA

COMPUTER SYSTEMS ARCHITECTURES

OPERATING SYSTEMS

DATABASEMANAGEMENT SYSTEMS

SOFTWAREENGINEERING

COMPUTER SYSTEM

COMPUTER BASEDINFORMATION SYSTEM

LEGAL ANDPROFESSIONAL

ASPECTS

HUMAN RELATIONS


INFORMATION SYSTEMS AND ORGANIZATION

TECHNOLOGY

(HW, SW, NETWORKS)

GOALS ANDPERFORMANCE

(BUSINESS STRATEGY, ECONOMIC CRITERIA)

PROCESSES

(PRODUCTION, ADMINISTRATION,COMMUNICATION, ETC.)

ORGANIZATION

(ORGANIZATION DESIGN)

SOCIAL ENVIRONMENT

(VALUES, COOPERATION)

SOURCE: G. BRACCHI,G. MOTTA 1993


(PRE)HISTORICAL DEVELOPMENT OF INFORMATION SUPPORTING TECHNOLOGIES

in nostra potestateNos Agilulfus 1°

statuemus ut tibiagrum fertilissi.detur pro 40 tall.

CLAY (EBLA XXIV° SEC. B.C.) PAPYRUS (EGYPT XII° SEC. B.C.)PARCHMENT (EUROPE XII° SEC. A.D.)

PAPER FILES (XVII° SEC.) PUNCHED CARDS (FORTIES) MAGNETICAL SUPPORTS (SIXTIES)

��

�

��

�

��

� ��

��

�


INFORMATION SYSTEMS AND DATA TECHNOLOGY

FILE SYSTEM

DATA BASESYSTEM

MANAGEMENTINFORMATION

SYSTEM

INFORMATIONRETRIEVAL

DECISIONSUPPORTSYSTEM

QUERYANSWERING

SYSTEM

EXPERTSYSTEM

NATURAL LANGUAGE

PROCESSING

MATHEMATICALLOGIC

STATISTICS,OPERATIONAL RESEARCH


INFORMATION FLOWS

INFO

RM

ATIO

N

MANAGEMENT

OPERATIONAL LEVEL

DIR

ECTI

VES


INFORMATION SYSTEMS TYPES

• FOR THE PRODUCTION PROCESSES– Electronic Data Processing (EDP) SYSTEMS

• MANAGEMENT INFORMATION SYSTEMS– EXECUTIVE REPORT SYSTEMS (EIS)

• DECISION SUPPORT SYSTEMS– STRATEGIC DECISION SUPPORT


INFORMATION SYSTEMS TYPES

SOURCE: P. F. Camussone 1990

GOAL USAGEMODE

FUNCTIONALAIM

MODELFLEXIBILITY

TEMPORALSTABILITY

EDP PASSIVE EFFICIENCY CURRENT ACTIVITIES

CONSTANT ANDCONSISTENT

MISTIMELINESS AND

RELIABILITY

DSS EFFICACY

TEMPORAL FEATURES

DATA FEATURES

CLERICALACTIVITIES

INTEGRATOR/SUBSTITUTE

VALIDITY, PRECISION,ACCURACY

BUILT-INSTANDARD

PROCEDURES

INFORMATIONGENERATOR

FORROUTINARY

MANAGERIAL CONTROL

A CAREFULREADING OF

INFORMATIONIS REQUIRED

EFFICIENCYAND

EFFICACYSUMMARIZE

PAST ACTIVITIESCONSTANT AND

CONSISTENT

STANDARDREPORTING WITH

EXCEPTIONEVIDENCING

POORLY STRUCTUREDMANAGERIAL

ACTIVITIESSUPPORT

USERSSTRONG

INVOLVMENTIS REQUIRED

MAINLYDEAL WITH

FUTURE ACTIVITIESAND UNDERSTANDINGOF PAST SITUATIONS

REASONABLE ANDJUSTIFIABLE

APPROXIMATIONS

ON REQUESTMODEL

BUILDING

EXTREMEFLEXIBILITY


INFORMATION SYSTEMS MODELS

THEY ORIGINATE FROM SPECIFIC EVOLUTIONS OF GENERAL THEORIES ON ORGANIZATION SYSTEMS• MANAGERIAL MODELS (MIS)

INFORMATION PROVIDED BY THE INFORMATION SYSTEM IS USED TO CONTROL THE ORGANIZATION (CYBERNETIC VIEW)

» GENERAL THEORIES (MISSION AND GOAL OF MIS)• FORRESTER, ANTONY, SIMON, SCOTT-MORTON

» SEGMENTATION INTO SUBSISTEMS• BLUMENTHAL, BSP, NOLAN

• SOCIAL MODELSTHE EFFECTS OF COMPUTER TECHNOLOGIES ARE CONSIDERED BOTH ON THE I. S. AND ON THE OPERATION PROCEDURES


SIMON’S MODEL (1960)

ORGANIZATION LEVELS FOR DECISIONPROCESSES

– PHYSICAL, PRODUCTION, DISTRIBUTION PROCESSES

– (PROGRAMMED, STRUCTURED) DECISIONS FOR CONTROLLING ROUTINE OPERATIONS

– (NON PROGRAMMED, UNSTRUCTURED) DECISIONS FOR EVALUATING THE OPERATIONAL DECISIONS AND RULES CHANGES RESULTS

PROGRAMMED DECISIONS CAN BE AUTOMATED


ANTHONY’S MODEL (1965)

A MODEL FOR MANAGEMENT CONTROL

– OPERATIONAL CONTROLIT WORKS ON PREDEFINED ACTIVITIES

– MANAGEMENT CONTROL (SHORT TERM)BUDGET AND OPERATIONAL PLANS FORMULATION AND VERIFICATION OF THE RESULTS

– STRATEGIC PLANNING (MEDIUM/LONG TERM)DETERMINATION OF THE ORGANIZATION’S GENERAL GOALS

IT BINDS THE MISSION OF INFORMATICS TO PROVIDING THE OPERATIONAL AND MANAGEMENT CONTROL WITH STRUCTURED DATA


MANAGERIAL ACTIVITIES (ANTONY)TYPES OF DECISIONS / TASKS (SIMON)

OPERATIONAL CONTROL MANAGEMENT CONTROL STRATEGIC PLANNING

STRUCTURED

SEMI-STRUCTURED

UNSTRUCTURED

PROCUREMENT

INVOICING

STOCK TRADING

PRODUCTION PROGRAMMING

CHOOSING A MAGAZINECOVER PAGE

SALES PLANNING PLANT LOCATION

CONSUMER PRODUCTS BUDGETING

EXECUTIVES RECRUITING

FINANCIAL PLANNING

R&D PLANNING

PRODUCT PLANNING

SOURCE: Keen e Scott-Morton 1978

GORRY E SCOTT-MORTON’S MODEL (1971)MERGES SIMON’S AND ANTHONY’S MODELS

PLACEMENT OF THE DECISION PROCESS IN THE GRID IS NOT DETERMINISTIC, BUT IT DEPENDS ON THE GOALS AND ON THE SOCIAL AND ORGANIZATIONAL CONTEXT


ANTHONY-NOLAN’S MODEL (1978/79)

CONDUZIONE

IMPI

ANTI

CONT

ROLL

O MAC

CHIN

ARI

MAN

UTEN

ZION

E

RAPO

RTI G

IORN

ALIE

RI

ACCE

TTAZ

IONE

MAT

ERIA

LI

MAG

AZZI

NIM

OVIM

ENTA

ZIO

NE M

ATER

IALI

PRO

GRA

MM

AZ. S

TABI

LIM

ENTI

PRODUCTION

GENER.PLANNING

PIAN

O ST

RATE

GICO

ED O

PERA

ZION

IPR

EVIS

IONI

EC

ON

OM

ICHE

MAN

OD

OPE

RA

RICA

VI

E CO

STI

SALES DISTRIBUTION

SALES

FINANCE ACCOUNTING PERSONNEL SERVICES

FINANCE

LANC

IO O

RDIN

IAV

ANZA

MEN

TO O

RDIN

I

EVAS

IONE

ORD

INI

REG

ISTR

AZIO

NE O

RDIN

IFI

LIAL

I E C

ONC

ESSI

ON

ARI

GES

TIO

NE C

ENTR

IPR

EPAR

AZIO

NE D

OCU

MEN

TIPR

OG

RAM

MAZ

. CAR

ICH

IIN

STR

ADAM

ENTO

FATT

URAZ

ION

E E

VER

IFIC

API

ANIF

ICAZ

. DIS

TRIB

UTI

VAG

ESTI

ON

E C

ASSA

ADEM

PIM

ENTI

FIS

CAL

I

AUD

ITIN

G

FATT

UR

AZ. E

CO

NT.

CLI

ENTI

GES

TIO

NE

CR

EDIT

I

PAG

HE

CONT

ABIL

ITA’

CONT

ABIL

ITA’

FO

RNIT

ORI

CONT

ABIL

ITA’

GEN

ERAL

E

FORM

AZIO

NE

ADEM

PIM

ENTI

LEG

ALI

SERV

IZI A

I DIP

ENDE

NTI

GEST

IONE

RET

RIBU

ZION

I

BIBL

IOTE

CHE

RAPP

ORTI C

ON AZ

IONI

STI

SERVI

ZI LE

GALI

CONTROLL

O QUAL

ITA’

E C

OLLAU

DI

PRODUCTION ACCOUNT.ACQUIST

IPIA

NIFICA

Z. CO

MMESSE

PIAIF.

PUNT

I RIO

RDINO

PIANI

F. CA

RICO

IMPIA

NTI

PROG

RAMM

AZ. P

RODU

ZIONE

CONT

ROLL

O SC

ORTE

PREV

ISIO

NI D

OMAN

DAPI

ANI IN

TROD

UZ. P

ROFIT

TIPR

OMOZ

IONE

VEN

DITE

GEST

IONE

VEN

DITE

PIAN

IF. V

OLUM

E PR

ODOT

TOAN

ALIS

I E P

REVI

S. V

ENDI

TERI

CERC

HE D

I MER

CATO

ANAL

ISI D

I RED

ITIV

ITA’

ECC

.

ANAL

ISI P

ORTA

FOGL

IO

ANAL

ISI IN

VEST

IM. P

ATRI

MON.

PREV

ISIO

NI IN

VEST

IMEN

TI

PREV

ISIO

NI FA

BBIS

OGNO

CAS

SA

VALO

RIZZ

AZIO

NE S

CORT

E

STIM

E E SI

MULA

ZIONI

ANAL

ISI C

OSTI

BUDG

ETING

COSTI S

TANDA

RD

PLANNING

MANAGEMENTCONTROL

OPERATIONALCONTROL


AN I.S. FOR THE OPERATIONAL LEVEL (MANUFACTURING COMPANY)

• IT MUST BE DECOMPOSED INTO SUBSETS WHICH ARE TYPICAL OF THE COMPANY ACTIVITY

• REFERENCE AREAS– MANAGEMENT ACTIVITY

» RESEARCH AND DEVELOPMENT (R&D)» PRODUCTION» LOGISTICS (PURCHASES, WAREHOUSES, TRANSPORTATIONS)» COMMERCIAL (MARKETING, SALES)» FINANCE

– SURVEY ACTIVITY» ADMINISTRATION AND CONTROL

– ORGANIZATIONAL ACTIVITY» ORGANIZATION» PERSONNEL MANAGEMENT


AN I.S. FOR A MANUFACTURING COMPANY

DESIGN DB. MAINTENANCE DB. MEDIUM TERM PLAN ACCOUNTING PERSONNEL

WAREHOUSE MANAG.

WAREHOUSE DESCR.

DATA INPUT DATA

INPUT

DAILY PLAN

PART PROGRAM

PERSONNEL ATTENDANCE

PLANTMONITORING

MACHINETOOLS

UNITWORKSTATION

UNITWORKSTATION

ROBOTARMS

TECHNICALDIRECTION

I.S.

S.I. PERPIANIFICAZIONE E

CONTROLLO DI GESTIONE

ADMINISTATIVEI.S.

LOGISTICSI.S.

PART LIST

NEW PRODUCTSSPECIFICATION

COMMERCIAL DATA

HANDLINGBILLS

STOWAGE,TAKING

FAIL

URE

DATA

PROT

OTYP

ES T

ESTS

PART

PRO

GRAM

AN

D PR

ODUC

T. C

YCLE

S

PRODUCTION PROGRAMS

PRODUCTION DATA

PERSONNEL DATA

PART LISTEXPLOSION


IBM BUSINESS SYSTEM PLANNING (BSP 1971)

USAGE USAGE

ORIGIN ORIGIN

PARTICIPATE IN

PERFORMED BY

INFORMATION

FUNZIONIORGANIZZATIVE PROCESSES

• IT IDENTIFIES INFORMATION NEEDS AND INFORMATION SYSTEMSSEGMENTATION

• IT CONTEMPLATES THE INFORMATION USAGE IN ALL OFCOMPANY PROCESSES

• IT IS A METHOD FOR BUILDING SYSTEM MODELS IN ORDER TO EVALUATE AUTOMATION OPPORTUNITIES


CRITIQUE OF MIS

• IT SHOWS THE RELATIONS BETWEEN INFORMATION-DECISION AND INFORMATION-CONTROL

• IT IGNORES THE SOCIAL EFFECTS OF THE EDP AS WORK AUTOMATION

• IT DOES NOT EXPLAIN THE CONNECTION BETWEENDATA PROCESSING AND INFORMATIONPROCESSING


MAGGIOLINI’S MODEL

A FLOW OF DOCUMENTS AS A LOG OF TRANSACTIONS ON THE SYSTEM RESOURCES WHICH WORKS UNDER COORDINATION AND CONTROL OF THE DECISION SYSTEM

• THE INFORMATION SYSTEM– CORRELATES INFORMATION FOR THE DECISION

SUPPORT SYSTEM– IS FED-UP BY INPUTS BOTH EXTERNAL AND INTERNAL

TO THE DATA SYSTEM– IS A FUNCTION OF THE FEATURES OF THE DECISION

SUPPORT SYSTEM• THE DATA SYSTEM

– CORRESPONDS TO THE WORLD OF OPERATIVE PROCEDURES

– ITS FEATURES DEPEND ON THE OPERATIVE PROCESSES AND ON THE DETAIL LEVEL OF THEIR TRANSACTIONS


MAGGIOLINI’S MODEL

ELECTRONIC PROCESSING PROVIDES:– THE DATA SYSTEM

WITH A TECHNOLOGY TO LOWER THE COST OF DOCUMENT PRODUCTION

– THE INFORMATION SYSTEMWITH A TOOL TO IMPROVE INFORMATION QUALITY

THE BENEFITS OF INFORMATION SYSTEMS AUTOMATION ARE PROPORTIONAL TO THE VALUE OF THE INFORMATION FOR THE DECISION LEVEL

INFORMATICS IS AN ORGANIZATION TECHNOLOGY TO MANAGE THE COMPANY PRODUCTIVE FACTORS


INFORMATION-DATA CORRELATION

ENVIRONMENT

ORGANIZATION

DECISION SYSTEM

ELECTRONIC DATA PROCESSING SYSTEM

EXTERNAL DATA

INFORMATION SYSTEM

INTERNAL DATA

INFORMATION

INFORMATION

INFORMATION

RESOURCES PRIMARY OPERATIONAL PROCESS PRODUCTS AND SERVICES

DECISIONS


EFFECTIVENESS AND FAILURES

• PERRONE (1973)– INFORMATION IS A FACTOR OF DECISION AND

CONTROL– IT IS BOYCOTTED BY THE MIDDLE MANAGEMENT WHO

IS LOOSING POWER• ACKOFF (1967)

– DEMOLISH THE TALES ABOUT INFORMATION ABUNDANCE TO GET BETTER DECISIONS

– FILTER USEFUL INFORMATION» DEFINE THE INFORMATION PARAMETERS OF THE

CONTROLLED PROCESS» DEFINE THE PROCESSING MODES OF INFORMATION IN

THE DECISION PROCESS• LUCAS (1975)

– TOO MUCH TECHNOLOGY AND TOO LITTLE STUDY AND UNDERSTANDING OF ORGANIZATIONS BEHAVIOUR


STRATEGIC POTENTIAL OF INFORMATION TECNOLOGY (IT)

• IT IS A STRATEGIC SUCCESS FACTOR– IMPACT ON THE PROCESS: IT IS AN INTEGRAL PART IN

FORMULATING THE STRATEGY» IDENTIFICATION OF HIGHEST COST POINTS» IDENTIFICATION OF HIGHEST VALUE ADDED

POINTS– IMPACT ON THE PRODUCT:

» PRODUCTS SUBSTITUTION» ACTUAL PRODUCTS IMPROVEMENT

• IT IS A NECESSARY CONDITION TO SURVIVE

• INFORMATION TECHNOLOGY IS LITTLE APPLICABLE


MODEL OF PORTER AND MILLAR

INFORMATION CONTENT IN THE PRODUCT

INFO

RM

ATIO

N C

ON

TEN

T IN

TH

E PR

OC

ESS

LOW

LOW

HIGH

HIG

H

SMALL CONSTUCTION FIRMS

MEDIUM BASE CONCERNS(CONCRETE, STEEL, …)

BANKS

INSURANCE COMPANIES

HIGH-TECH SERVICE INDUSTRY

JUST IN TIMEMANAGEMENT

(AUTO)

REAL TIMEDISTRIBUTION(BENETTON)


INFORMATION SYSTEMS DESIGN

• MANY DIFFERENT MODELS EACH WITH A PECULIAR VIEW

• VIEWS ARE DIFFERENTIATED ABOUT– THE MODEL TOPIC

» DATA» PROCESSES

– THE MODEL LEVEL» USER REQUIREMENTS» CONCEPTUAL» IMPLEMENTATION

• MODEL INTEGRATION


DESIGN SEGMENTS

SOURCE: G. BRACCHI,G. MOTTA 1993

TOPICDATA PROCESSES

ABSTRACTIONLEVEL

USERREQUIREMENTS

CONCEPTUAL DESIGN

IMPLEMENTATION

DATA DRIVEN

PROCESS DRIVEN

•INFORMATION CLASSES

•USER VIEWS

•ORGANIZ. ACTIVITIES

•PROCESSED INFORMAT.

•ENTITIES•RELATIONSHIPS•ATTRIBUTES

•PROCESS STRUCTURE

•I/O PROCESSES

•DBMS

•LOGIC SCHEMA

•LANGUAGES

•PROGRAM CODING


DATA DRIVEN DESIGN APPROACH

USER

VIEWS

CONCEPTUAL SCHEMA

LOGICAL/PHYSICAL SCHEMA

PROCESSSTRUCTURE

PROGRAMS


PROCESS DRIVEN DESIGN APPROACH

PROCEDURAL

VIEWS

CONCEPTUALSCHEMA

LOGICAL/PHYSICAL SCHEMA

PROCESSSTRUCTURE

PROGRAMS

ORGANIZATIONALPROCEDURE

SCHEMA


TYPICAL APPLICATIONS

SYSTEM TYPE APPROACH COMMENTS

ELECTRONIC FILING(REGISTERS)

TRANSACTIONS PROCESSING

OPERATIONALPROGRAMMING

REPORTING

DATA DRIVEN

PROCESS DRIVEN(COMPLEX PROCEDURES)

DATA DRIVEN(SIMPLE PROCEDURES)

EITHER PROCESS DRIVENOR MIXED

OUTPUT DRIVEN(DATA)

THE GOAL IS TO ACCESS STORED INFORMATION

THE ENPHASIS ON PROCESSES IS DUE TO THE IDENTIFICATION NEED OF THE STEPS, OF THE EVENTS, AND OF INFORMATION IN THE COMPANY’S PROCEDURE

THE DATA ANALYSIS IS BASED ON THE ANALYSIS OF THE REPORTS TO BE GENERATED

DA: G. BRACCHI, G. MOTTA 1993


HOW TO SET UP A PROJECT

• FROM SCRATCH– CONCEPTUALLY IMPORTANT– NOT VERY FREQUENT

• PROTOTYPE IMPLEMENTATIONS– SUCCESSIVE RELEASES– FUNCTIONAL SEGMENTS

• REENGINEERING– “REVERSE ENGINEERING” TECHNIQUES

• PACKAGE ASSEMBLING– PARAMETERIZATION– PERSONALIZATION

• OUTSOURCING


TREND IN I.S. DEVELOPMENT

ANALYSIS AND DEVELOPMENTFROM SCRATCH

COMPONENTS INTEGRATIONAND

PARTS REUSE


TREND IN I.S. DEVELOPMENT

• THE INFORMATION GLOBALIZATION CALLS FOR OPEN INFORMATION SYSTEMS WHICH CAN EVOLVE STEP BY STEP

• THE ORGANIZATIONS COMPLEXITY CALLS FOR COOPERATIVE INFORMATION SYSTEMS

• THE HETEROGENEITY OF THE RESOURCES AND OF THE TECHNOLOGIES CALLS FOR INTEROPERABILITYAND INFORMATION INTEGRATION TECHNIQUES


DE L’OUTSOURCING

1. - L’armi ausiliarie, che sono l’altre armi inutili, sono quando si chiama uno potente, che con le armi sue ti venga ad aiutare edefendere: come fece ne’ prossimi tempi papa Iulio; il quale, avendo visto nell’impresa di Ferrara la trista prova delle sue armi mercenarie si volse alle ausiliarie; e convenne con Ferrando re di Spagna che con le sue genti ed eserciti dovesse aiutarlo. Queste armi possono essere utile e buone per loro medesime; ma sono per chi le chiama quasi sempre dannose; perché, perdendo, rimani disfatto; vincendo, resti loro prigione.

Niccolò Machiavelli

Il Principe, Cap XIII


PROJECT INTEGRATION

• INTEGRATION NEED AMONG LEVELS AND TOPICS

• ORIZONTAL COHESION AMONG DATA AND PROCESSES

– CHECK FOR THE EXISTENCE IN THE DATA BASE OF ALL THE DATA NEEDED BY THE PROCESSES

• VERTICAL COHESION REQUIREMENTS-PHYSICAL

– CHECK FOR CORRESPONDENCE BETWEEN THE REQUIREMENTS AND THE IMPLEMENTATION


PROJECT METHODOLOGIES

• DESCRIBE THE PATH ON THE SEGMENTS GRID

• SPECIFY DATA AND PROCESS REPRESENTATION MODELS AT DIFFERENT LEVELS

• DESCRIBE DERIVATION AND INTEGRATION PROCESSES TO BE APPLIED

• SPECIFY POSSIBLE MODELLING AND INTEGRATION SYSTEMS AND TOOLS


MODELS AND TOOLS FOR SYSTEM ANALYSIS

• ABSTRACT AND SEMIFORMAL TECHNIQUES

• GRAPHICAL REPRESENTATION MORE INTUITIVE AND WIDESPREAD THAN THE LINGUISTIC ONE

• CASE TOOLS CONNECT THE GRAPHICAL AND THE LINGUISTIC INTERFACE



• DATA FLOW DIAGRAM (DFD)– CLASSICAL TOOL TO REPPRESENT PROCEDURES BY

MEANS OF SUCCESSIVE REFINEMENTS– EMBEDDED IN MANY CASE TOOLS– IT IS AMBIGUOUS (E.G. NO CONDITIONAL

CONSTRUCTS)

• ENTITY-RELATIONSHIP (E-R)– VERY POPULAR TOOL TO REPPRESENT DATA– USED BY MANY CASE TOOLS



• STRUCTURED ANALYSIS AND DESIGN TECHNIQUE (SADT)

– A VERY RICH REPRESENTATION OF PROCEDURE– IT LACKS A CONNECTION WITH DATA– DIFFICULT FOR PROCESS DESIGN

• INFORMATION SYSTEMS ANALYSIS OF CHANGES (ISAC)

– POWERFUL FOR PHYSICAL FLOWS REPRESENTATION– SAME POWER AS DFD TO REPRESENT INFORMATION

FLOWS– IT CAN BE COMBINED WITH ANY MODEL FOR

PROCESSES AND DATA SPECIFICATION



• PETRI NETS– OPERATIONAL MODEL TO SPECIFY SYSTEM

OPERATION – DISTINCTION BETWEEN OPERATION FLOW AND

CONTROL OR INFORMATION FLOW– USEFUL TO DESCRIBE PHYSICAL PROCEDURES

• HIERARCHICAL INPUT PROCESS OUTPUT (HIPO)

– IT DEFINES THE COMPUTING PROCESSES STRUCTURE– STRUCTURED AND HIERARCHICAL (TOP-DOWN)

ANALYSIS– FLEXIBLE DECOMPOSITION (SPECIALIZATION,

DISAGGREGATION, ...)• .....

Documents

Politecnico di Milano - Intranet DEIBhome.deib.polimi.it/schreibe/dbmanagementsystems/materiale/pdf/... · executive report systems (eis) ... model flexibility temporal stability