Adaptive User Interface
type: Class
subclass of: User Interface
UFO: subtypeOf Object
description: Interface adapted to meet the needs of users.
is defined by: HCIO-ON AUI System Ontology

Age
type: Class
subclass of: Measurable User Profile Element Type
description: Age refers to the chronological age of the user (Morris; Venkatesh, 2000)

Average Experience Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode offers a standard-feature interface and moderate navigation. @E.g., full menus, basic shortcuts, and limited customization for users with regular technology use.

Basic Experience Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode simplifies the interface with minimalist layouts and essential features, making it easier for novice users to navigate. @E.g., reduced menus, larger icons, and step-by-step guidance for users with less technological familiarity.

CognitiveDisability
type: Class
subclass of: Disability
description: "Cognitive, learning, and neurological disabilities involve neurodiversity and neurological disorders, as well as behavioral and mental health disorders that are not necessarily neurological. They may affect any part of the nervous system and impact how well people hear, move, see, speak, and understand information. Cognitive, learning, and neurological disabilities do not necessarily affect the intelligence of a person." https://www.w3.org/WAI/people-use-web/abilities-barriers/#cognitive

Contrast Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: Some people need high contrast between text and background, including many older people who lose contrast sensitivity from ageing. Some read better with dark text on light background. W3C Web Accessibility Initiative (WAI), 2025.

Desktop Mode
type: Class
subclass of: User Interface Customization
disjoint with: Mobile Mode
description: This mode adapts the interface to larger screens, optimizing the layout. @E.g., resizable windows, expandable menus and keyboard shortcuts, ideal for computers and notebooks.

Disability
type: Class
subclass of: Nominal User Profile Element
description: Disability refers to disabilities that result from illness and injury, including physical, mental or emotional limitations or difficulties that a person has as a result of these disabilities (Altman, 2014)

Dyslexia
type: Class
subclass of: CognitiveDisability
type: NamedIndividual
description: Dyslexia is a language-based learning disability of neurobiological and developmental origin that impairs an individual’s ability to acquire accurate and fluent reading skills, as well as spelling development (Roitsch; Watson, 2019).

Education Level
type: Class
subclass of: Measurable User Profile Element Type
description: User education issues, including for example university diplomas. (GOLEMATI, et al., 2007)

Experience Level
type: Class
subclass of: Measurable User Profile Element Type
description: Experience Level refers to the user’s familiarity with and knowledge of a system or technology (Tomasi; Schuff; Turetken, 2018) Level of user experience in relation to technologies, subdivided into: - Basic Experience; - Average Experience; - High Experience.

Font Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: Font Mode adapts font size, type, and color to improve readability and accessibility of the interface. @E.g., Larger font for low vision, sans-serif for dyslexia, high contrast for color blindness.

Gender
type: Class
subclass of: Measurable User Profile Element Type
subclass of: Nominal User Profile Element
description: User gender.

High Experience Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode provides an advanced interface with complex features. @E.g., advanced shortcuts and detailed settings for highly tech-savvy users.

Language
type: Class
subclass of: Nominal User Profile Element
description: Facilitate the pronunciation and interpretation of abbreviations or text in a foreign language. Language tagging allows search engines to search for and identify documents in a given language, and is also an important aid for assistive technologies. (KULPA, 2009)

Low Vision
type: Class
subclass of: Vision Disability
type: NamedIndividual
description: Low Vision is defined as a condition of vision loss that cannot be corrected by glasses, contact lenses, surgeries or medical treatments, refers to a visual limitation that affects the ability to perform daily activities, even with the help of optical aids (WHO, 2019). Low Vision can be classified into Re- duced Vision, Light Sensitivity, Visual Acuity, and Contrast Sensitivity.

Measurable User Profile Element Type
type: Class
subclass of: User Profile Element Type
UFO: subtypeOf Quality Universal
description: Quality Universal in UFO that allows the assignment of values according to a quality structure, such as Age, Education Level, and Experience Level.

Mobile Mode
type: Class
subclass of: User Interface Customization
description: This mode adapts the interface to mobile devices, with a responsive layout and touch-optimized navigation. @E.g., larger buttons, simplified menus, and swipe gestures are ideal for smartphones and tablets.

Nominal User Profile Element
type: Class
subclass of: User Profile Element Type
subclass of: Restriction
  on property: refersTo
  some values from: User
UFO: subtypeOf Mode
description: Instance of a Nominal User Profile Element Type that characterizes a particular User. For example, Alex’s Gender is male and Language is English.

Readable Interface Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode adapts the interface to improve readability by adjusting spacing, alignment, and highlighting important text elements. @E.g., Increased line spacing, text justification, highlighting links with contrasting colors or underlining to make them easier to read.

Screen Reader Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode uses assistive technologies to transform visual content into audio or braille. @e.g., Text to Speech, which converts text to audio; Keyboard Navigation, which allows mouse-free interaction; and Visual Description, which provides context about images and icons.

User
type: Class
UFO: subtypeOf Person
description: A Person who interacts with (or is expected to interact with) an Interactive Computer System. E.g., a person who uses a home banking system, smart watch or smart mobile phone.
is defined by: HCIO User Sub-Ontology

User Interface
type: Class
UFO: subtypeOf Object
description: All components of an interactive system (software or hardware) that provide information and controls for the user to accomplish specific tasks with the interactive system. E.g., mouse, keyboard, monitor, sensors and the software that handle them.
is defined by: HCIO Interactive Computer System Sub-Ontology

User Interface Customization
type: Class
subclass of: Adaptive User Interface
subclass of: Restriction
  on property: affects
  some values from: Adaptive User Interface
subclass of: Restriction
  on property: aimsToSatisfy
  some values from: User
subclass of: Restriction
  on property: basedOn
  some values from: Nominal User Profile Element
subclass of: Restriction
  on property: basedOn
  some values from: User Interface Customization Recommendation
UFO: subtypeOf Disposition
description: Mode Universal in UFO that classifies possible interface adaptations. Refers to the customizations (i.e., adaptations) that must be made to the system interface for a given user, based on information from the Context of Use (environment, device, situation, etc) and the User Profile (skills, limitations, etc).

User Interface Customization Recommendation
type: Class
subclass of: Adaptive User Interface
UFO: subtypeOf Object
description: Formal indication of how the User Interface should be customized to better suit a specific User, based on the values of one or more User Profile Elements. These recommendations are defined through rules derived from WCAG guidelines and represented in the AUISO ontology. E.g., if the User has Low Vision, the recommendation may include increasing font size and contrast.

User Profile Element Type
type: Class
subclass of: User
subclass of: Restriction
  on property: characterizes
  some values from: User
UFO: subtypeOf Intrinsic Moment Universal
description: A type of intrinsic characteristic that describes aspects of a user. It can be a Nominal User Profile Element Type (e.g., gender, language, disability) or a Measurable User Profile Element Type (e.g., age, education level, experience level).
is defined by: HCIO-ON User Profile Ontology

User Profile Element Value
type: Class
subclass of: User Profile Element Type
subclass of: Restriction
  on property: refersTo
  some values from: Measurable User Profile Element Type
subclass of: Restriction
  on property: refersTo
  some values from: User
UFO: subtypeOf Quale
description: User Profile Element Value refers to the value of a Measurable User Profile Element Type that characterizes a particular User. An Quale is the specific value that a quality assumes in an individual. E.g., the exact shade of red of a particular apple or the temperature “36.5°C" of a person.

Vision Disability
type: Class
subclass of: Disability
description: Vision Disability refers to the impairments, limitations, and restrictions that a person with an eye condition faces, encompassing a range of visual impair- ments that affect the visual system and its functions, including difficulty seeing clearly, recognizing faces, or navigating environments (WHO, 2019)

Voice Command Mode
type: Class
subclass of: User Interface Customization
type: NamedIndividual
description: This mode allows you to interact with the interface using voice commands. @E.g., open applications, navigate between menus or dictate texts using only your voice.

Alex
type: NamedIndividual
type: User
has disability: Dyslexia
has experience level: Beginner
has age: 25

Maria
type: NamedIndividual
type: User
has disability: Low Vision
has age: 40

S3
is rule enabled: true
comment: Dyslexia
type: Imp
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Dyslexia
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Font Mode for Dyslexia

S10
is rule enabled: true
comment: Dyslexia
type: Imp
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Dyslexia
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Readable Interface Mode

S1
is rule enabled: true
comment: Low Vision
type: Imp
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Low Vision
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Contrast Mode

S2
is rule enabled: true
comment: Low Vision
type: Imp
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Low Vision
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Font Mode Increase Size

S7
is rule enabled: true
comment: Low Vision
type: Imp
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Low Vision
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Readable Interface Mode

S8
is rule enabled: true
comment: Low Vision
type: Imp
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Low Vision
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Screen Reader Mode

S9
is rule enabled: true
comment: Low Vision
type: Imp
body: IndividualPropertyAtom
  property predicate: hasDisability
  argument1: http://www.example.org/aui#u
  argument2: Low Vision
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Voice Command Mode

S6
is rule enabled: true
comment: User Advanced
type: Imp
body: IndividualPropertyAtom
  property predicate: hasExperienceLevel
  argument1: http://www.example.org/aui#u
  argument2: Advanced
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: High Experience Mode

S4
is rule enabled: true
comment: User Beginner
type: Imp
body: IndividualPropertyAtom
  property predicate: hasExperienceLevel
  argument1: http://www.example.org/aui#u
  argument2: Beginner
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Basic Experience Mode

S5
is rule enabled: true
comment: User Intermediate
type: Imp
body: IndividualPropertyAtom
  property predicate: hasExperienceLevel
  argument1: http://www.example.org/aui#u
  argument2: Intermediate
body: ClassAtom
  class predicate: User
  argument1: http://www.example.org/aui#u
head: IndividualPropertyAtom
  property predicate: hasUserInterfaceCustomizationRecommendation
  argument1: http://www.example.org/aui#u
  argument2: Average Experience Mode