Information Modelling Approach

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• Information Modelling Approach

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BAA 3032 - IS in CE
Todays objectives Process Modeling

• Understand the logical modeling of processes
  through studying examples of data flow diagrams.
• Define and design the process modeling

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• The Need For Information Modelling
• Modelling is a process of representing a
  perceived reality in a simplified way. Modelling
  A/E/C information is a task that can be generally
  characterised by the complexity of the
  information and processes involved in
  construction industry.
• This complexity is contrived by the complex
  nature of the construction industry, including a
  great amount of inter-related aspects of
  information, many participants involved in the
  processes concerning the product, and different
  views on the product.
• Thus, the aim is to model this complex
  information in order to improve the
  representation of the information and to enhance
  the communication process.

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• Definition
• Information modelling or conceptual modelling
  consists of a collection of objects, their
  properties, their relationships with other
  objects, their memberships in classes, and their
  relationship constraints and cardinalities
  Turner, 1992.
• Atre 1988 defines an information modelling
  as
• An inherent model of the entities with the
  properties representing them, together with
  relationships interconnecting the entities ..
• Alagic 1986 1989 defines an information
  modelling as
• A suitable representation of an applications
  environment An abstract representation of that
  environment relevant for the information
  requirement of the application

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• Information Modelling Concept
• Construction organisation is made up of complex
  interrelated systems
• For this systems to function properly, the
  system requirements and both the data and process
  within the systems should be identified, well
  understood and analysed in a structured way so
  that the output information provides an actual
  representation for the system under
  consideration.
• This is achieved through modelling of data and
  process to produce Information Models for the
  organization as shown in the figure below

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• Process Model
• The modelling approach helps in identifying the
  various processes involved and the data they
  require. This can be represented in an
  interaction model which shows what data is
  required for a certain process.
• A process takes input data and transforms it
  into output data. Many processes involve
  storage or retrieval of information from
  permanent data files or entities.
• Process model technique has been used in a number
  of projects for analysing the information flow
  between different information processing
  activities in the design and construction
• E.g. retrieving information from geotechnical
  report file (data store) during the Foundation
  design process and retrieving budget
  information from the client (data source)
  during the process estimating cost
• The output from one process will often provide
  an input to another process hence it is important
  to view all data which flows between process as a
  single concept Data Flow.

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• Process Model (cont)
• The Data Flow Diagram (DFD) is a technique for
  process modelling which shows the input and
  output of the concerned process and also a
  breakdown of each of the main processes.
• These ideas are known as the structured
  approach to system analysis introduced by IBM in
  the 1960s for software development further
  developed in 1970s by others such as DeMarco and
  Gane and Sarson.
• Other Techniques
• Integrated Computer Aided Manufacture Definition
  Method (IDEF0)
• Structured Analysis and Design Technique (SADT)
• Object Flow Diagram (OFD)
• Function decomposition
• Structure Charts
• HIPO Diagrams (Hierarchical Input, Process
  Output)
• Warnier-Orr Diagrams
• Action Diagrams
• Decision tree
• HOS (Higher Order Software Charts)

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DFD Symbol
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• Data Model
• Data model is a set of concepts that can be used
  to describe the structure and operations of a
  database. The idea of a data model is to define
  the behaviour to be included in a database in
  response to the complexity of constructing large
  database for organisations.
• Sibley 1974 define a data model is a model of
  the real world concepts and relations that are to
  be encoded into a database. A data model also
  provides the basic structuring mechanisms for
  describing the data, relationships and
  constraints of the information stored in any
  information system. Using a specific data model,
  conceptual models can be built.
• The basic concept used in almost all data models
  are the Entities, Attributes and Relationships.

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• Data Model (cont)
• Entities An entity is something, real or
  abstract, about which we store data. It is of
  fundamental importance to an organisation.
  Example CRANE, SITE, ENGINEER, INVOICE, BOQ, SUB
  CONTRACTOR, etc.
• Attributes An attributes is a basic unit of
  information which describes an entity. An entity
  has various attributes that we wish to record
  such as value, size, name, etc.
• Relationships A relationship is an association
  between entities showing how they are related
• Examples
• ENTITY ATTRIBUTES INSTANCE.
• CONTRACTOR CONTRACTOR NAME Zinadane Zidane
• CONTRACTOR CODE Zz
• SUPPLIER SUPPLIER NAME Stello
• SUPPLIER CODE BS 446
• SUPPLIER ADDRESS KL
• ENTITY RELATIONSHIP ENTITY
• CONTRACTOR May place many ORDER
• SUPPLIER May receive many ORDER

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• Data Model (cont)
• Data analysis need much help from end users to
  enable them to understand an organisations data
  and to design the data that will be most useful
  in managing the organisation. They need a clear
  ways of diagramming the data like those used in
  Entity Relationship Diagrams (ERD).
• Traditionally, the tool used for data model is
  the (ERD). However, developers used other tools
  such as NIAM Nijssen Halpin, 1989, IDEF1X
  Appleton, 1986 and EXPRESS Schenck, 1989.

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The Importance of Information Model
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The Importance of DFD

• DFD has a significant impact on the quality of
  the system development process as for example
  Rytheon has reported saving from 1988 through
  1994 of USD17.2 million in software cost where
  the structured analysis technique to analysis due
  to avoiding the rework to the requirement flaws.

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Information Modeling Concept
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The Example of Process Model using IDEF?
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The Example of Data Model
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System Architect for IM