Topic 1.2: System Design Basics Flashcards
What is ergonomics?
The scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance.
Simply put: How well the form fits the function
What is accessibility?
Refers to the design of products, devices, services, or environments for people with disabilities or specific needs.
Includes specialist peripherals/software like:
* Braille keyboards
* Eye-typers
* Accessible controllers
* Screen readers
* Voice synthesizers
What is usability?
The ease of use and learnability of a human-made object. The object of use can be a software application, website, machine, process, or anything a human interacts with.
Accessibility + ergonomics = usability
Some examples of usability problems with commonly used digital devices
- Difficult to handle/fiddly hardware
- Difficult to understand software
- Complex user interface
- Need to have lots of prior knowledge
- Specialist support needed to use device
- Each device is different to other similar devices (no standards)
What are ways to improve the accessibility of a system?
- Touch screens
- Voice recognition
- Text-to-speech
- Braille keyboard
What is a stakeholder?
- A person, group or organization that has interest or concern in an organization.
- Some examples of key stakeholders are creditors, directors, employees, government (and its agencies), owners (shareholders), suppliers, unions, and the community from which the business draws its resources.
- Not all stakeholders are equal. A company’s customers are entitled to fair trading practices but they are not entitled to the same consideration as the company’s employees.
Methods of obtaining requirements from stakeholders
Surveys: Involves handing out questionnaires for people to fill out.
Interviews: Involves the interviewing key people within the system to find out how it works.
Direct observation: Involves walking around the organisation watching how things are done with his/her own eyes.
Collecting documents: Involves looking in the documents currently being used in the system to try to find out how the present system works
Pros and cons of surveys
Advantages:
* Large amount of data from a large group can be gathered
* Takes little time to analyse (if done electronically)
* Simple
Disadvantages:
* It is hard to ask the ‘right question’
* Information gathered is limited by questionnaire, can be biased
* Quality of responses not ensured
Pros and cons of interviews
Advantages:
* Allows a lot of very detailed information to be gathered
* People can be asked about what they don’t like on the system
Disadvantages:
* Takes a long time
Pros and cons of direct observation
Advantages:
* Possibility of gathering first-hand, unbiased information
Disadvantages:
* Often people might not work the way they normally do when being observed
Techniques for gathering the information needed to arrive at a workable solution
Examining current systems: Before you do anything new, see what is currently being done.
Looking at competing products: Have a look at what the competitors are doing. The aim is not copy them, but to get an idea of what is possible/being done at the moment.
Organizational capabilities: Determining what the organisation would be capable of. Can they afford a new system/new equipment? Can the staff use the new system Training needed? Can they have any ‘downtime’ to upgrade?
Literature searches: Consulting literature to see what else might be out there (in IB terms, the term “literature” refers to book, magazines, web sites, journals, videos, academic papers…).
What are prototypes
Prototypes are abstract representations of the system, often focusing on only one or two key aspects of the system.
They are important in testing as each component of the system can be tested before implementing, and to illustrate the working of the future system to the client.
Purposes of a prototype
Fail early and inexpensively: by building a prototype, you can quickly weed out the approaches that don’t work to focus on the ones that do.
Gather more accurate requirements: interviews and focus groups can fall short because many people find it difficult to conceptualize a product before they see it. By developing a working prototype, you can demonstrate the functionality to help solidify requirements for the final design.
Technically understand the problem: by developing a functional prototype, you are forced to address both the foreseen and the unforeseen technical challenges of a device’s design.
What is iteration
Meaning 1: a procedure in which repetition of a sequence of operations yields results successively closer to a desired result (linked to prototyping)
Meaning 2: the repetition of a sequence of computer instructions a specified number of times or until a condition is met (links to loops, an alternative to recursion)
Why does failing to involve the end-user in the design process mean trouble?
- User may be unsatisfied with system
- System may be unsuited for user’s problem, affecting productivity