Human Factors, Ergonomics, Human Performance, Sensation and Perception - Assignment Example

Part 2: Human Attributes Study Number: Lecturer: Part 2: Human Attributes Study Section Definitions of the Field Definethe following concepts and indicate the relationships among them: 1.1. Human factors: Human factors can be defined as cognitive, physical factors or social behaviors specific to humans that can influence the performance of a computing device. According to Heim (2008), human factors are factors that relate to the psychology, biomechanics, engineering and anthropometry that in one way or another impact on the interaction with computers. They touch on the cognitive abilities of humans in the process of human and computer interaction. 1.2. Ergonomics Ergonomics is a concept that is synonymous to human factors. Heim (2008) defines it as “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”. This definition is also used by the international Ergonomics association. 1.3. Human performance In the human computer interface/interaction context, human performance can be defined as the measure of the effectiveness and efficiency of the interface is enhancing the performance of the intended activities. Human performance involves the determination of whether the employed human computer interface has the ability to satisfy occupational health and safety and productivity. 1.4. Human computer interface/interaction Human Computer interaction/ interface is the study, the planning and the design and uses of interfaces between users and computers (Heim, 2008). Computers are unique machines that are used for multiple functions on a daily basis. Additionally, they are complex hence they need an almost intimate interaction with human beings. The point at which the computer and the human (users) interact is known as the human computer interface (Heim, 2008). The four terms are all interrelated and contribute greatly to the design of a human computer interface. Human factors such as physical, social and cognitive abilities must be considered in ergonomics (design of human computer interfaces). Adequate and careful consideration of the human factors in ergonomics will eventually ensure that the human performance in relation to computer interaction is effective and efficient. All these are factors that form the key principles and considerations in the design of human computer interfaces/ interaction. Sensation and perception 2.1 Vision: 2.1.1 Define and show how this impacts design in general: Vision is the ability to discern what is displayed on a computer interface and enable the user to effectively communicate with the computer. Vision impacts design in a major way since it must be put into consideration by any human computer interface designer. Most important factor to consider in design is the visibility of the interface. It should not be too bright to hinder the ability to view what is on the screen and at the same time not too dark. 2.1.2 Provide an example of a specific characteristic and how it can be used to improve design: According to Heim (2008), vision is a major determinant for the effectiveness and efficiency of the human computer interface. As mentioned lighting of both the screen and the location of the computer affects the vision of the users. Therefore, in the design of a human computer interface it is important to include the option of allowing the user to adjust the brightness of the screen to suit their preferences. Another characteristic is the color schemes, a design interface should have proper color mixing to provide a good contrast. Good contrast combined with the ability to adjust lighting improves the human computer interface design and subsequent use. 2.1.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: Computers and other computing devices can be placed at stationary public places. For instance ATM machines. Therefore, it is important to consider the location and placement of stationary computers. They should face away from direct and too much lighting to prevent reflection of light that hampers the vision of the user. 2.2 Hearing: 2.2.1 Define and show this impacts design in general: Speech is currently used for both input and output from the computers. Users find this as one of the easiest and convenient paradigms of human computer interface. Therefore, during the design process a designer must consider speech output and input. The computer must understand what the user is communicating in order to process and give the results accurately. 2.2.2 Provide an example of a specific characteristic and how it can be used to improve design: Audibility is one of the major attribute or characteristic with regard to hearing. Both the user and the computer must be able to determine what the other one is trying to communicate. Therefore, during design of the human computer interfaces the designer must consider the ability of the user to hear. Additionally, they must also consider their ability to communicate through speech. 2.2.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: Sound is the major attribute that is associated with hearing. Hearing is affected by pitch and volume of the sound produced by the computer or the user. During the design of a human computer interface, the designer must minimize the volume by avoiding high and low volumes and at the same time avoiding high and low pitch sound to allow the effectiveness of the interface. Low and high pitch and volume affects the ability of the user to listen and impact on the human computer interaction. 2.3 Sensory limits: 2.3.1 Define and show how this impacts design in general: Human computer interactions entirely depend on three of the five common senses inherent in humans. The sense of sight, hearing and touch are used to interact with computers on a daily basis. Therefore, sensory limits have to be considered in the design of human computer interfaces. There are users who are deaf or blind and even those with eyesight problems therefore it is important to consider these sensory limits in designing human computer interfaces. 2.3.2 Provide an example of a specific characteristic and how it can be used to improve design: Sensory limits have thresholds and deficiencies in audio, visual and even touch. Design can be improved by making displays legible and audible. These are necessary for designing a usable interface. 2.3.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: Absolute judgment limits should be avoided in a good interface design. The designer should avoid asking the user to determine the level of a variable on the basis of a single variable such as color, size or pitch. Additionally, the designer should avoid close similarities since is results in confusion particularly to users with sensory limits. 2.4 Perception: 2.4.1 Define and show how this impacts design in general: Perception is basically the ability to understand and become aware of a particular thing through the use of senses. Essentially, perception is defined by how once perceives. In the human computer interface context a user is able to perceive what they touch, see and hear from the computer (Heim, 2008). Consequently, the design of the interface must ensure that the right message and communication is perceived by the user. For instance a user using a machine with speech output can hear one thing different from what the computer is communicating hence the user will have a wrong perception. 2.4.2 Provide an example of a specific characteristic and how it can be used to improve design: Perception is influenced by what comes out of the computer; therefore, the design of the human computer interface should consider output from the interface. To enhance perception the designer can use high resolution and strong image polarity. Additionally, perception can be enhanced by use of visual and audio enhancements to provide attractiveness and aide visual processing and perception. 4.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: A characteristic of perception is that the meaning can be changed by simple design principles. The output from the computing device could mean one thing but the user perceives it as a totally different thing. The designer should avoid cluttering to eliminate the inability to perceive correctly. Cognitive Processing and Performance 2.5 Memory: 2.5.1 Define and show how this impacts design in general: The use of computers and other electronic devices requires the user to use several commands to enable the computer to perform the intended tasks. Therefore, one has to memorize the commands needed to perform a particular task. The designer must therefore factor in the user’s ability to memorize commands by using simple and understandable interfaces. 2.5.2 Provide an example of a specific characteristic and how it can be used to improve design: Design of the interface can be improved by maintaining simplicity in the design process. The user is able to memorize simple commands and instructions as opposed to complex commands. This can easily be achieved by use imagery and representations. For instance the designer should use simple icons and buttons that can be easily memorized by the user. 2.5.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: The designer should avoid inconsistency in the design of the interface. Consistency enables a user to use any design more comfortably with few adjustment due to the ability to memorize. Once there is inconsistency, the user will find it difficult to use the new interface because commands and steps will change. 2.6 Thinking, reasoning, problem solving and decision making: 2.6.1 Define and show how this impacts design in general: Users receive information comprehend it then think about it through reasoning and even problem solving before making a decision. This is sometimes referred to as cognitive workload and may interfere with how users respond to information on the interface (Heim, 2008). The designer must ensure that the users attention and the thinking, reasoning, problem solving and decision making tasks are not interfered with. 2.6.2 Provide an example of a specific characteristic and how it can be used to improve design: One characteristic of these attribute is proximity and compatibility. The thinking, reasoning, problem solving and decision making may at times require the user to source information from different areas of the interface; therefore, ensuring that there is adequate proximity and compatibility of these sources in the interface is a step towards a good human computer interface design. 2.6.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: To perform these cognitive tasks the user may also need several information to complete the task. The designer must minimize the information access cost in terms of time and effort employed in accessing the needed information. A user’s attention may be diverted if he is forced to move from one location to another to access information needed for decision making or problem solving. 2.7 Cognitive processing limits: 2.7.1 Define and show this impacts design in general: Different users have different cognitive processing limits. For instance, a technical user has the ability to think reason and even perform advanced problem solving and decision making tasks. On the other hand, a non-technical user can do simple or limited cognitive tasks. This impacts design in general since the designer must put into consideration the cognitive ability and limitations of each user for which the interface is intended. 2.7.2 Provide an example of a specific characteristic and how it can be used to improve design: The cognitive limitations can be addressed by designing using more visual information that is less likely to consume the user’s memory. The design of the user interface can be improved by using menus, checklists, or any other displays that can effectively aide the users with cognitive limitations. 2.7.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: A good design should avoid tasks that are resource demanding particularly in regard to mental resources of the user. This can be achieved by using simpler perceptual tasks that enables the user to focus on the current tasks and conditions and also consider future conditions in their tasks. 2.8 Motivation: 2.8.1 Define and show how this impacts design in general: Motivation can also be associated with attention and also the acceptability of the interface. Simply put, the design of an interface must be done in such a way that the user is motivated to continue using the interface. In essence, a well-designed human computer interface should effectively and efficiently meet the user’s needs in order to warrant motivation. 2.8.2 Provide an example of a specific characteristic and how it can be used to improve design: One characteristic of motivation that can be used for a good design is learnability. The user will be motivated to use an interface that is easy to learn and comprehend. Hence, the designer must employ techniques such as simplicity and attractiveness that enhance learnability and motivation of the user; 2.8.3 Provide an example of a specific characteristic and how and why it should be avoided in a good design: On the other hand the designer must avoid a lot of attention and cognitive load that are associated with tasks performed by the user. This can be achieved by using design concepts that requires users to use little memory and recall of steps or sequence of activities. The designer can use menus, checklist, and option buttons among other design techniques. Motor system issues 2.9 Motor system and responder limits: 2.9.1 Define and show how this impacts design in general: Motor systems involve the user’s ability to move around. Human computer interaction requires one to move their body parts particularly the limbs and general body movement. This has an impact in the design of the interface since the designer must incorporate needs and abilities of all users. 2.9.2 A specific characteristic and how it can be used to improve design: Mobility is one characteristic of the motor system and responder limits. The user should be able to experience adequate mobility with regard to the interface. Humans generally have limited reach and strength. Therefore, the designer should design interface that enable the user to comfortably move their limbs and other body parts while executing their tasks. 2.9.3 A specific characteristic and how and why it should be avoided in a good design: In particular, the designer should limit the design of stationary interfaces and interactions that will force the user to change position or strain to use the service. 2.10 Input devices in relation to motor control: 2.10.1 Define and show how this impacts design in general: Human body parts particularly the fore limbs have to move while using the input devices such as the keyboard, mouse among other devices. 2.10.2 A specific characteristic and how it can be used to improve design: The most important characteristic of input devices in relation to motor control is its responsiveness. The user supplies a command through the input device by either typing, or clicking. This command is executed by the computer to give a feedback to the user. The designer must therefore factor in the responsiveness of the interface. It should be fast and reliable in providing feedback on whether the input is being processed. 2.10.3 A specific characteristic and how and why it should be avoided in a good design: Keyboard layout designs and required mouse actions often cause users to change body positions in order to execute them. Hence, the design of these devices and their interfaces must ensure that there is minimal movement to reduce health problems associated with movement. Reference. Heim, S. (2008). The Resonant Interface : HCI Foundations for Interaction Design. Carlifornia: Pearson/Addison Wesley. Read More