China
Africa
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Blueprint Reading
Published in Frank R. Spellman, The Science of Wind Power, 2022
Early on, dimensioning (or measuring using basic units of measurement) was rather simple and straightforward. For example, in the time of Noah and the Ark, a cubit was the length of a man's forearm, or about 18″. In pre-industrialized England, an inch used to be “three barleycorns, round and dry.” More recently, we have all heard of “rule of thumb.” Actually, at one time, an inch was defined as the width of a thumb, and a foot was simply the length of a man's foot.
Some Basic Concepts of Mechanics
Published in G. Boothroyd, C. Poli, Applied Engineering Mechanics, 2018
Length is a measure of displacement or relative position. In ancient times, the forearm (cubit) was used as the standard unit of length. However, since forearms differ in size from person to person, obvious difficulties arise in using such a definition. Later, in 1793, the French used the length of a straight line scratched on a bar kept under closely monitored conditions in Paris as the standard unit of length. The length of the line was called a metre and was one ten-millionth of the distance from the equator to the north pole on a line running through Paris. In 1889 the definition of the metre was standardized as the distance (at 0°C) between two fine lines on a platinum-iridium bar preserved at the International Bureau of Weights and Measures in Sevres, France. Today, the metre is defined∗ as follows: “The metre is the length equal to 1,650,763.73 wavelengths in vacuo of the radiation corresponding to the transition between the levels 2p10 and 5d5 of the krypton-86 atom.” This standard is believed to be reproducible to about 2 parts in 108. This standard is not used for everyday work. National Standards laboratories will calibrate reference standards up to 1 metre by direct interferometric methods and to an accuracy of about 1 part in 107. These reference standards are used to calibrate the various working standards used in industry.
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Published in Mara Cercignani, Nicholas G. Dowell, Paul S. Tofts, Quantitative MRI of the Brain: Principles of Physical Measurement, 2018
Developed in about 3000 BC in ancient Egypt, the cubit was a ubiquitous standard of linear measurement, equal to 524 mm. It was based on the length of the arm from the elbow to the extended fingertips and was standardised by a royal master cubit of black granite, against which all cubit sticks used in Egypt were to be measured at regular intervals.10 The precision of the thousands of cubit sticks used in building the great Pyramid of Giza is thought to have been very high, given that the sides of the pyramid are identical to within 0.05%.
Study on Vietnamese Design Methods of Traditional Vernacular Architecture and Discussion on Their Technical Origins
Published in International Journal of Architectural Heritage, 2023
In this regard, it is considered that the use of people's lengkat to determine the size of the tool served as a standard for the design unit (in the case of Ruler C) is a type of human dimension dating from very early antiquity such as the Foot/Pace, Hand/Finger/Lengkat, Cubit/Thumb, and Open arms/Depa alit/A penyujuh system were popular in over the World (Oliver, P. Encyclopedia of Vernacular Architecture of the World). Meanwhile, although the shape and function of Ruler B are similar to Ruler C, the length of each side of Ruler B may have been unitized by the length of the “Xich” scaled unit originally influenced by ancient China civilization (Dau 1997, Bang 1902).
Distance matters: mobilities and the politics of distance
Published in Mobilities, 2018
In their study of residents’ descriptions of their apartments in New York, Linde and Labov (1975) distinguish between two types, which they call ‘map’ and ‘tour.’ The first type abstracts the apartment: ‘The girl’s room is next to the kitchen’; the second type is more bodily and operational: ‘you turn right and come into the living room.’ Their findings show that only 3% of the interviewees used the map type – all the rest preferred walking over seeing; moving over picturing. Michel de Certeau (1984) uses this study to suggest a short genealogy of maps. Medieval maps included only the tours (performative instructions chiefly concerning pilgrimages), the main stops one was to make, and distances calculated in hours or in days. With the rise of modern science, however:[T]he map gradually wins out […] it colonizes space; it eliminates little by little the […] practices that produce it. Transformed first by Euclidean geometry and then by descriptive geometry, constituted as a formal ensemble of abstract places […] The tour describers have disappeared. (Ibid., 121)Historically, the first measurement units were imprecise, uneven extensions of body parts (cubit, digit, foot) or of time (the distance of a cigarette or of a two-day walk) (cf. Lefebvre 1991; Scott 1998). It is only towards the end of the eighteenth century that standard units were established: the meter was determined to be the ten-millionth part of the meridian distance between the earth’s pole and the equator, and the nautical mile the equivalent of one minute of latitude. Abstraction and comparison play a crucial role in making it possible to standardize the gaze at different sites, giving sweeping preference to absolute space – amenable to mapping, surveying, and standardization – over the relational perspective, in which space cannot be considered apart from its practiced aspect (Beer 2016). What this historical development meant, however, was not only a transformation in the representation of the world, but also a radical shift in the way it is perceived. The world itself changes when it is looked at differently.