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Developing an IT ApplicationUsing Advantage:Gen
Activity Modeling
Objectives of Activity Analysis
To understand the processes of the firm independent of organization structure, existing IS, and technology
To verify the understanding with users To lay the foundation for system design
Business Activities
Function – a high level process, a group of activities that together completely support one aspect of furthering the mission of the business (e.g., AMP of Resources, Conversion, MSC of Products/Services)
Process – a group of related events Elementary process – an event, and
maintenance of RALs (CRUDE)
Processes
Results from the decomposition of a function
A process is a lower level activity (or activities) that does one of:– produce outputs necessary outside the business– gathers new information for the business– produces new information for the business– controls things in the business
Naming a Process
Processes (events) are named using a verb (action) plus a noun (an entity type or attribute), e.g. TAKE ORDER, STAFF PROJECT
Process versus Procedure
Process - what the business does, a specific action the business requires, e.g. CHARGE CUSTOMER
Procedure - how the action is carried out, e.g. PRINT INVOICE
Activity Analysis Techniques
Decomposition - Functions decompose into smaller functions or processes, processes into smaller processes. This is represented in the Activity Hierarchy Diagram
Dependency Analysis - This shows the conditions necessary to enable one process/event to execute and thus the dependency of one process/event on another. This is shown in the Activity Dependency Diagram (ADD confirms the AHD).
Hierarchy Diagramming
ROOT
FUNCTION A
FUNCTION B
PROCESS X
PROCESS Y
Decomposition Rules
Functions may be decomposed into sub-functions or processes
Processes may be decomposed into sub-processes, and ultimately, elementary processes
An activity that is decomposed must be broken down into two or more activities (parent has at least two children)
An activity is totally described by its subordinates (sum of children should explain entire parent)
Functions and processes may exist at the same level, but only as decompositions of different parents
FUNCTION A
SUB-FUNCTION F
SUB-FUNCTION G
FUNCTION B
PROCESS X
PROCESS Y
A is a more complex function than B
Decomposition Using Business Events
Identify process that follows an important business event
Event - Customer returns defective product Subsequent events (making up the process)
- Give customer an exchange, Refund money, Return defective product to supplier
Elementary Processes, the Lowest Level of the Hierarchy
Achieves a useful business result Leaves the business in a consistent state,
i.e. preserves referential integrity, data integrity of attribute values, and integrity of the business transaction
In general performed by one person, in one location, until complete
Integrity of the Data
The two events should be modeled as one elementary process, because executing only one means that the value of inventory is inconsistent with the sale recorded.
These would be sub-elemental
SELL PRODUCT
REDUCE INVENTORY
Can users trust the data stored in the database?
Activity Dependency Analysis
Determines the conditions necessary to enable the execution of a process (lowest level process is an event or maintenance of RALs).
Since one process (or event) can supply the conditions necessary for another process to execute, this shows dependencies between processes (events).
Activity Dependency Diagramming
Verifies the process decomposition Adds to business understanding by identifying
data needed to execute a process and the information that it provides
Activity Dependency Occurs When
The post condition of one process is the necessary precondition of another process
REVIEWINVENTORYITEM
LOW STOCK PLACE ORDER
Dependency Types
Sequential Dependency
SELECT PRODUCT
SELECT DISTRIBUTOR
NEGOTIATEPRICE
Dependency Types
Parallel Dependency
RECEIVEORDER
INSTALLASSET
PLACE IN WAREHOUSE
PAY FORORDER
Prerequisite event
Dependent events
Dependency Types
Mutually Exclusive Dependency
OINTERVIEWAPPLICANT
MAKE JOBOFFER
REJECTAPPLICANT
Activity Dependency Diagram for “Acquire and Pay for Fixed Assets”
Sequential dependency
Mutually exclusivedependency
Parallel dependency
Events and External Objects
An external or temporal event is something that occurs which then triggers some response, e.g. End of Month can trigger INVENTORY REVIEW
External objects (agents) provide data to a process or receive some results from the process e.g. CUSTOMER, VENDOR, GOVERNMENT AGENCY
Both (1) external events and (2) external objects can be depicted in ADD’s