Systems Development – System Design

 Systems Development – System Design
 

Learning Outcomes:

• Describe the functions of each part of a computer-based system and the related issues.
• This covers the hardware platform, software, inputs, outputs, user interfaces, database structures, data processing, data control, data security and system security.
• Design and appraise an effective interface between the user and the system.
• Different types of human-machine interfaces are compared.
• Know system flowcharts, structure charts, data flow diagrams and data dictionaries to design and document a proposed system.
• Use Gantt Charts for project management.

 

User interfaces

 

• Graphical user interface (GUI)
• Advantages: easy to use, customized interface possible
• Input methods: keyboard, mouse, touch screen
• Screen components: mouse pointer/cursor, icon, menu, button, graphics
• Users: novice

•  Command line interface (CLI)
• Advantages: faster than GUI, keyboard only, in plain text and file format
• Users: experienced user

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  2017 1d.

AL CS2(2003-2012): 2006 10b. 2009 9ac. 2011 10b.

 

System flowcharts

Symbols to be memorized:

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  -

AL CS2(2003-2012): 2008 9e. 2009 9e. 2010 8e. 2012 8f.

 

Structure charts

It gives an overview of the system with its modules and their interaction.

Control information: e.g. Boolean data indicating the validity of the input data

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  SP 4c. 2012 2b.

AL CS2(2003-2012): 2006 3a.

 

Data flow diagrams

 

The purpose of data flow diagram is to map out the data flow of the system.

Tips: classify the given information into data, entity, process and database.

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  2013 3c. 2015 4a.

AL CS2(2003-2012): 2004 13c. 2005 13e. 2007 8ab. 2008 9d. 2009 9d. 2010 8ab. 2011 10a. 2012 8c.

 

Gantt Charts

Arrows: to show the dependent relationship i.e. Task 3 depends on the results of Task 1 and Task 2

Critical path: the minimum time to complete the project. In this case: Task 1 à Task 3.

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  PP 2ci. 2013 3a. 2015 2a. 2017 1a.

AL CS2(2003-2012): -

Learn more (Critical path): AL CS2: 2003 3. 2004 3a. 2005 4. 2006 13a. 2007 2. 2009 1. 2012 3.

  

References:

https://www.geeksforgeeks.org/difference-between-cli-and-gui/

https://www.smartdraw.com/flowchart/flowchart-symbols.htm

https://www.geeksforgeeks.org/software-engineering-structure-charts/

https://www.smartsheet.com/content/gantt-chart-critical-path