HCI.docx

**HCI-**Study of designing computers to best serve users **User Experience (UX) design-** Field closely related to HCI, focusing on user satisfaction **Dexta haptic gloves**- Invent to mimic touch sensations in virtual reality **Pre-touch sensing**-Technology predicting user actions on smartphone...

**HCI-**Study of designing computers to best serve users **User Experience (UX) design-** Field closely related to HCI, focusing on user satisfaction **Dexta haptic gloves**- Invent to mimic touch sensations in virtual reality **Pre-touch sensing**-Technology predicting user actions on smartphones **PaperID-**Digitizing paper into a touchscreen for IoT connectivity **Virtual reality-** Technology creating immersive simulated environments **Self-driving cars-** Autonomous vehicles navigating without human input **Touch screen technology-** Interactive display technology operated by touch **Daniel Jackson-** MIT Professor emphasizing user interaction design importance **Human capabilities-** Abilities influenced by emotions and competency **Visual angle -**Indicates the portion of view an object occupies **Visual acuity** Ability to perceive detail, limited by distance **Size constancy** Perception of familiar objects as constant size **Brightness** Subjective reaction to light levels **Color** Composed of hue, intensity, and saturation **Optical illusions** Perceptual distortions due to visual system compensations **Saccades** Rapid eye movements between fixation points **Fixations** Strong interest in something or someone **Syntax** Arrangement of words to form well-formed sentences **Semantics** Concerned with meaning and implication **Pragmatics** Focuses on conversational implicature **Outer ear:** protects inner and amplifies or increases sound **Middle ear**: transmits sound waves as vibrations to inner ear. **Inner ear**: chemical transmitters are released and cause impulses in auditory nerve.**Pitch**: sound frequency.**Loudness**: amplitude.**Timbre**: type or quality. **Auditory system** filters sounds and can attend to sounds over background noise.**Thermoreceptors** Receptors sensing heat and cold **Nociceptors** Receptors sensing pain **Mechanoreceptors** Receptors sensing pressure or tension **Reaction time** Time taken to respond to a stimulus **Movement time** is dependent on age, fitness, etc.**Time** taken to respond to stimulus: reaction time + movement time. **Sensory Memory** Buffers for stimuli received through senses. Includes iconic memory for visual stimuli, echoic memory for aural stimuli, and haptic memory for tactile memory. **Iconic** memory: visual stimuli **Echoic** memory: aural stimuli.**Haptic** memory: tactile memory. **Short-term Memory** Acts as a scratch pad for temporary recall with rapid access in 70ms and rapid decay in 200ms **Long-term Memory** Serves as a repository for all knowledge with slow access, slow decay, and a huge/unlimited capacity. **Episodic** -- serial memory of events.**Semantic** -- structured memory of facts, concepts, and skills. **Decay** -- information is lost gradually but very slowly. **Retroactive interference:** new information replaces old.**Proactive inhibition**: old may interfere with new. **Inductive reasoning** assuming; can or cannot be true. **Deductive reasoning** derive logically necessary conclusion from given premises; logical / reasonable thinking **Abductive reasoning** can lead to false explanations. **Gestalt theory** problem solving form both productive and reproductive**.** **Problem space theory** problem solving involves generating states using legal operators.**Slips** right intention, but failed to do it right. **Mistakes**- wrong intention, misinterpreted. **Keyboards** Most common text input device **layout -- QWERTY** Standardised layout **Dvorak** common letters under dominant fingers**Maltron left-handed keyboard** A specialized keyboard designed for left-handed users to reduce fatigue and improve typing efficiency. **Chord** **keyboards** Keyboards with only a few keys (four or five) where letters are typed as combinations of keypresses, ideal for portable applications and fast typing once trained. **T9 entry** A method of text input on phone keypads using numeric keys with multiple presses to input letters, with predictive text capabilities. **Handwriting recognition** The input of text into a computer using a pen and a digitizing tablet, requiring natural interaction and overcoming technical challenges like interpreting different handwriting styles. **Speech recognition** The technology that allows spoken words to be converted into text, most successful with limited vocabularies and single users. **Mouse** A handheld pointing device for computers with planar movement and buttons for selection, requiring physical space and providing relative movement to control the screen cursor. **Mechanical mouse detection** A method for detecting mouse motion where a ball on the underside of the mouse turns as it is moved, rotating orthogonal potentiometers to track movement. **Optical mouse detection** A method for detecting mouse motion using a light-emitting diode on the underside of the mouse, detecting alterations in reflected light intensity for relative motion calculation. **Touchpad** A small touch-sensitive tablet used mainly in laptop computers where strokes move the mouse pointer, requiring good acceleration settings for different stroke speeds. **Trackball** A pointing device where a ball is rotated inside a static housing to move the cursor, providing fast and accurate control, often used in gaming. **Joystick** An indirect input device for controlling movement in games or 3D navigation, with pressure on the stick determining velocity and buttons for selection. **Touch-sensitive screen** A display that detects the presence of a finger or stylus, allowing direct interaction but may suffer from imprecision and finger marks. **Stylus** A pen-like pointer used for drawing directly on touch-sensitive surfaces, commonly found in PDAs and tablet PCs. **Digitizing tablet** A device similar to a mouse with crosshairs, used on special surfaces for accurate digitization such as maps. **Eyegaze** An interface controlled by eye gaze direction, often used for evaluation and requiring high accuracy with potential for hands-free control. **Cursor keys** The four keys (up, down, left, right) on a keyboard for basic motion tasks, although slow and lacking a standardized layout. **Bitmap** **displays** Screens composed of a vast number of colored dots, with resolution indicating the number of pixels and color depth determining the range of colors available per pixel. **Anti-aliasing** A technique to soften edges and reduce jagged lines in digital images, improving visual quality by using shades of line color. **Cataracts** High incidence in VDU operators **Reproductive disorders** Concern over miscarriages and birth defects **Liquid Crystal Displays** Light passes through polarised plates, changes color with voltage **Random Scan** Draws lines directly, no jaggies, rarely used **Direct View Storage Tube (DVST)** Similar to random scan but persistent, no flicker **Plasma Displays** Wide screen technology, used in video walls **Projected Displays** Uses RGB lights or LCD projectors **Situated Displays** Located in public places, display or interactive **Digital Paper** Thin flexible sheets updated electronically **Virtual Reality (VR)** Interacting in 3D space, using helmets and gloves **3D Displays** Ordinary screens with 3D effect, use stereoscopic vision **VR Headsets** Small screens for each eye, creating 3D effect **VR Motion Sickness** Caused by conflicting cues, motivates tech improvements **Simulators and VR Caves** Projected scenes, realistic environment with physical controls **Sounds** Used for error indications and confirmation of actions **Haptic Devices** Provide touch and feel feedback in games and simulations **BMW iDrive** Control menus with haptic feedback for easier selection **Printing** Image made from small dots, critical features include resolution and speed **Dot-Based Printers** Include dot-matrix, ink-jet, bubble-jet, and laser printers **Fonts** Particular styles of text, measured in points **Readability of Text** Lowercase for easy reading, uppercase for individual letters **Serif Fonts** Helps readability in long printed text lines **Page Description Languages** Converts complex pages into bitmaps for printing **PostScript** A page description language used to send instructions for curves, lines, text in different styles, etc., similar to a programming language for printing. **WYSIWYG** Acronym for \'what you see is what you get,\' representing the aim of word processing where the on-screen display matches the printed output. **Scanners** Devices that convert paper documents into digital images, with two types: flat-bed scanners for whole-page scanning and hand-held scanners for digitizing strips. **Optical character recognition** Abbreviated as OCR, it is the process of converting a bitmap image of text back into editable text, involving segmenting text, decomposing it into lines and arcs, and deciphering characters. **Paper-based interaction** Refers to using paper as both output and input, with technologies like OCR, scanning, and glyphs used for identification and control applications. **Short-term Memory -- RAM** Random access memory (RAM) is a type of short-term memory stored on silicon chips with an access time of 100 nanoseconds and a data transfer rate of around 100 Mbytes/sec. **Long-term Memory -- disks** Refers to storage on magnetic disks, with floppy disks storing around 1.4 Mbytes and hard disks typically ranging from 40 Gbytes to hundreds of Gbytes. **Flash-Memory** A type of memory used in devices like PDAs and cameras, which is silicon-based and persistent, often used for data transfer via plug-in USB devices. **Compression** The process of reducing the amount of storage required, with lossless compression recovering exact data and lossy compression recovering something similar to the original. **Storage formats -- text** Includes formats like ASCII, UTF-8, RTF, SGML, and XML, each serving different purposes in storing text with varying encoding and layout information. **Storage formats -- media** Refers to the various formats for storing images and audio/video files, such as PostScript, GIF, JPEG, TIFF for images, and QuickTime, MPEG, WAV for audio/video. **Finite processing speed** The limitation imposed by the finite speed of processing, which can lead to issues like cursor overshooting, icon wars, and rapid scrolling through help screens. **Moore\'s law** The observation that processor speed doubles approximately every 18 months, leading to faster computers over time, as noted by Gordon Moore, co-founder of Intel. **Networked computing** Enables access to large memory and processing capabilities, shared resources, and other people, but can face issues like network delays, conflicts, and unpredictability. **The internet** A brief history of the internet\'s growth, starting from DARPANET in 1969 to its widespread adoption with common protocols like TCP and IP for communication. **INPUT DEVICES** Hardware used to provide data to a computer for interaction and control, allowing the entry of raw data for processing. **OUTPUT DEVICES** Computer hardware that converts information into human-readable form, including text, graphics, tangible outputs, audio, or video. **TEXT ENTRY DEVICES** Devices like mouse, joystick, touchpad, stylus pen, and keyboard used for entering text and commands into a computer system. **DISPLAY DEVICES** Hardware like Plasma Display, LCD, LED, and ELD used to visually present information on screens or panels. **MEMORY DEVICES** Includes short-term memory (RAM), long-term memory on disks, and flash memory used for storing data in various computing devices.