Unknown-importance Westerns articles
wiki page ID: 67829034
wiki page revision ID: 1026650190
type: Concept

Just-noticeable difference
wiki page edit link: http://en.wikipedia.org/w/index.php?title=Just-noticeable_difference&action=edit
comment: In the branch of experimental psychology focused on sense, sensation, and perception, which is called psychophysics, a just-noticeable difference or JND is the amount something must be changed in order for a difference to be noticeable, detectable at least half the time (absolute threshold). This limen is also known as the difference limen, difference threshold, or least perceptible difference.
wiki page history link: http://en.wikipedia.org/w/index.php?title=Just-noticeable_difference&action=history
abstract: In the branch of experimental psychology focused on sense, sensation, and perception, which is called psychophysics, a just-noticeable difference or JND is the amount something must be changed in order for a difference to be noticeable, detectable at least half the time (absolute threshold). This limen is also known as the difference limen, difference threshold, or least perceptible difference. For many sensory modalities, over a wide range of stimulus magnitudes sufficiently far from the upper and lower limits of perception, the 'JND' is a fixed proportion of the reference sensory level, and so the ratio of the JND/reference is roughly constant (that is the JND is a constant proportion/percentage of the reference level). Measured in physical units, we have: where is the original intensity of the particular stimulation, is the addition to it required for the change to be perceived (the JND), and k is a constant. This rule was first discovered by Ernst Heinrich Weber (1795–1878), an anatomist and physiologist, in experiments on the thresholds of perception of lifted weights. A theoretical rationale (not universally accepted) was subsequently provided by Gustav Fechner, so the rule is therefore known either as the Weber Law or as the Weber–Fechner law; the constant k is called the Weber constant. It is true, at least to a good approximation, of many but not all sensory dimensions, for example the brightness of lights, and the intensity and the pitch of sounds. It is not true, however, for the wavelength of light. Stanley Smith Stevens argued that it would hold only for what he called prothetic sensory continua, where change of input takes the form of increase in intensity or something obviously analogous; it would not hold for metathetic continua, where change of input produces a qualitative rather than a quantitative change of the percept. Stevens developed his own law, called Stevens' Power Law, that raises the stimulus to a constant power while, like Weber, also mu[cell cut: 3809 characters, first 2000 kept]
wiki page ID: 597564
subject: Category:Psychophysics
subject: Category:Perception

David Nabarro
birth place: United Kingdom
type: Politician
wiki page history link: http://en.wikipedia.org/w/index.php?title=David_Nabarro&action=history
type: Q82955
type: Q5
birth date: 1949-08-26
subject: Category:People educated at Oundle School
birth place: England
subject: Category:British public health doctors
subject: Category:Living people
subject: Category:Alumni of the London School of Hygiene & Tropical Medicine
subject: Category:World Health Organization officials
birth place: London
type: Q24229398
type: Person
type: Agent
subject: Category:British officials of the United Nations
comment: David Nabarro CBE (born 26 August 1949) is a Special Envoy on Covid-19 for the World Health Organization. He has made his career in the international civil service, working for either the Secretary-General of the United Nations or the Director-General of the World Health Organization. Since February 2020, he has helped the DGWHO deal with the COVID-19 pandemic.
wiki page edit link: http://en.wikipedia.org/w/index.php?title=David_Nabarro&action=edit
subject: Category:Academics of the London School of Hygiene & Tropical Medicine
subject: Category:Sephardi Jews
wiki page ID: 1364926
type: Thing
subject: Category:21st-century Sephardi Jews
education: University of Oxford
subject: Category:Alumni of the University of Oxford
subject: Category:Spanish and Portuguese Jews
type: NaturalPerson
subject: Category:Alumni of the University of London
type: Q215627
education: Oundle School
subject: Category:1949 births
subject: Category:United Nations operations in Iraq

List of spacewalkers
subject: Category:Spaceflight timelines
wiki page edit link: http://en.wikipedia.org/w/index.php?title=List_of_spacewalkers&action=edit
wiki page ID: 22289914
comment: This is a list of all astronauts who have engaged in an EVA by partly or fully leaving a spacecraft, exclusive of extravehicular activity on the lunar surface. It is ordered chronologically by the date of first spacewalk. For a list of astronauts who have performed lunar EVA ("moonwalks") see List of Apollo astronauts who walked on the Moon. For the 2017 docudrama film, see The Spacewalker.
wiki page history link: http://en.wikipedia.org/w/index.php?title=List_of_spacewalkers&action=history
subject: Category:Lists of astronauts
abstract: This is a list of all astronauts who have engaged in an EVA by partly or fully leaving a spacecraft, exclusive of extravehicular activity on the lunar surface. It is ordered chronologically by the date of first spacewalk. For a list of astronauts who have performed lunar EVA ("moonwalks") see List of Apollo astronauts who walked on the Moon. For the 2017 docudrama film, see The Spacewalker. The following 11 countries have flown spacewalkers: United States of America 129, Russia (formerly Soviet Union) 65, Canada, France, Japan 4, Germany 3 , China 2, Italy, Switzerland, Sweden and Great Britain 1 each. There have been 15 women who have taken part in an EVA.

Low-importance Westerns articles
wiki page ID: 67829028
wiki page revision ID: 1026649968
type: Concept

David Nabarro
language: en
type: Document
primary topic: David Nabarro

Just-noticeable difference
primary topic: Just-noticeable difference
type: Document
language: en

List of spacewalkers
language: en
type: Document
primary topic: List of spacewalkers