Process Modeling
Process Modeling is a technique of organizing documenting the structure and flow of data through a system¶s processes and the logic, polices and procedures to be implemented by a system¶s processes. Programme structure chart Logical flow chart or decision table
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Use of Logical Process
There are used to document an information system¶s process focus from the perspective of the system owners and system users.
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Data Flow Diagram (DFD)
A tool that depicts the flow of data through a system and the work or processing performed by that system. OR This include bubble chart, transformation graph and process model.
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Symbols in DFD
Process or work to be done External agent or the boundary of the system Data stores or file or database Data flows or input or output
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Different Between DFD & Flowchart
Process on DFD can operate parallely but in flowcharts can execute only one at a time. DFD show the flow of data though the system by using arrows. But in flow chart it show the sequence of processes or operation in the operation. DFD shows processes that are dramatically different timing. It doesn¶t happen in flowchart.
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System Thinking
The application of formal systems theory and concept to systems problem solving. This will helps us to understand the way system are organized and how they work
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Process Concepts
Input System/ Process Feed back & Control loop Out put
The System Environment
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Process
A Process is work performed on or in response to incoming data flows or condition.
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Process Decomposition
A complete system is usually too difficult to fully understand when viewed as a whole. In System Analysis, we can decomposed system into logical subsystems, analysis and design.
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Logical Process and Conventions
Logical processes are work or actions that must be performed no matter how implement the system. System is divide to components and sub systems until we identify manageable subsystem of the overall system.
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3 Types of Logical Process
1. Functions:- ( Subsystem) Is a set of related and ongoing activities of the business. It has a start and end. It just continuously performs its work as needed. 2. Event:- (Transaction) An event is a logical unit of work that must be completed as a whole. An event is triggered by a discreat input and is completed when the process has responded with appropriate outputs. 3. Elementary Processes:- (Primitive Process) These are discreat, detailed activities or tasks required to complete that response to an event or they are the lowest level of detail depicted in a process model.
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Structured English
This is a language and syntax based on the relative strengths of structured programming and natural English, for specifying the underlying logic of elementary processes on process models.
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Structured English Procedural Construct Sample Template Structure
1. Sequence of steps Step 1 .. Steps n 2. Simple Condition steps ) then Condition Else Condition Case 1 If Case 2 if Nested if then- else If (
3. Complex Condition steps
4. Multiple Condition 5. One to many iteration 6. Zero to many iteration 2/20/2009
Do while (truth condition) Steps
Restriction of Structured English
1. Only strong, imperative verbs may used 2. Only names that have been defined in the project dictionary may be used 3. Formulas should be stated clear using appropriate mathematical notations 4. Undefined adjectives and adverbs are not permitted unless clearly defined in the project dictionary as legal values for data attributes.
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5. Blocking and identification are used to set off the beginning and ending of constructs and enhance readability 6. When in doubt, user readability should always take priority over programmer preference.
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Policy
A Policy is a set of rules that governs some process in the business. Policies are the basis for decision making.
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Decision Table
A Decision table is a tabular form of presentation that specifies a set of conditions and their corresponding actions. Decision table are very useful for specifying complex policies and decision making rules, but unfortunately people are not use that because of they are not familiar with the table.
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Process Modeling for Business Process Model
BPM is to support that view(or display) business process, act/control adequate processes between people and systems related business performing, manage a whole process efficiently.
Organization & Authority management -General manager : managing structure, folder, authority -Manager : managing user group, business type Process creation & Operation -Designer : design process, application -General user : business catalogue, business processor, process monitor Interoperating outer systems -Application registration -Web service, - Manage event & response Improving business process - Process simulator, report
How to construct the Process Model
The roject team understands the current system s Strengths, weaknesses, limitations, ro lems, o ortunities, and onstrains.
Data model
The team mem ers will now uild the corres onding rocess model.
Building a model
Functional decomposition
Finance Sales
Shipping
Planning
Data Flow Diagram (SSADM)
± Context diagram ± Entity ± Process ± Data Flow ± Data store
A Simple Process Model
CASE for Process Modeling
The Context Diagram
A process model used to document the scope for a system. also called the environmental model. It is describes the system within the context of its environment shows boundaries, external environment and major information flows
Context Diagram of Food Ordering System
Example: Context diagram
APPLICANT
APPLICATION PROCESSING SYSTEM PROCESSES/ACTIVITIES & DATA RECORDS OFFICE
REFEREE
ADMISSIONS OFFICER
Context Diagram
Customers
.
Sales orders
Accepted sales order file
0 Order Entry System
Rejected sales order report
Item numbers
Inventory System
President
Item prices
Context DFD
Club Member Promotion Member Credit Status Warehouse Accounts Receivable Member Order
Potenti l Member
various Inquiry Reponses New Subscription Subscription Offer Subscription Renewal
Member Servi es System
Revised Packing Order New Promotion Subscription Program various Sales Reports
various Promotion Reports various Subscription Reports Past Member Resubscription Offer various Member Reports Member Services
Marketing Department
The advantages of Context Diagram ..
1. 2. 3. 4. 5. Shows the scope of the system Focus on major inputs and outputs Focus on major agents Useful communication tool Picture is worth than thousand words
The functional Decomposing Diagram
Decomposition
Decomposition is the act of breaking a system into its component subsystems, processes, and sub processes. Each level of abstraction reveals more or less detail.
The functional Decomposing Diagram
Iterative process of breaking the description of the system into finer and finer detail .The process of breaking down a system into smaller components Allows the systems analyst to: Break a system into small, manageable subsystems Focus on one area at a time Concentrate on component pertinent to one group of users Build different components at independent times
Example: Functional decomposition
Applicant Submit application form Check entry requirements Check former results Communicate decision