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A Vavilov Center (of Diversity) is a region of the world first indicated by Nikolai Vavilov to be an original center for the domestication of plants. [3] For crop plants, Nikolai Vavilov identified differing numbers of centers: three in 1924, five in 1926, six in 1929, seven in 1931, eight in 1935 and reduced to seven again in 1940. [4] [5]
[5] Pliny the Elder writes extensively about agriculture from books XII to XIX; in fact, XVIII is The Natural History of Grain. [6] Crops grown on Roman farms included wheat, barley, millet, pea, broad bean, lentil, flax, sesame, chickpea, hemp, turnip, olives, pear, apples, figs, and plums. Others in the Mediterranean include:
English: Map of the world showing approximate centres of origin of agriculture and its spread in prehistory: eastern USA (4000-3000 years ago), Central Mexico (5000-4000 ya), Northern South America (5000-4000 ya), sub-Saharan Africa (5000-4000 BP, exact location unknown), the Fertile Crescent (11000 ya), the Yangtze and Yellow River basins (9000 ya) and the New Guinea Highlands (9000-6000 ya).
The Earth-centered, Earth-fixed coordinate system (acronym ECEF), also known as the geocentric coordinate system, is a cartesian spatial reference system that represents locations in the vicinity of the Earth (including its surface, interior, atmosphere, and surrounding outer space) as X, Y, and Z measurements from its center of mass.
Shift of the world's economic center of gravity since 1980 and projected until 2050 [7] Various definitions of geographical centres exists. The definitions used by the references in this article refer to calculations within the 2 dimensions of a surface, mainly as the surface of Earth is the domain of human cultural existence.
A special case of the center-of-momentum frame is the center-of-mass frame: an inertial frame in which the center of mass (which is a single point) remains at the origin. In all center-of-momentum frames, the center of mass is at rest , but it is not necessarily at the origin of the coordinate system.
In biomechanics, center of pressure (CoP) is the term given to the point of application of the ground reaction force vector. The ground reaction force vector represents the sum of all forces acting between a physical object and its supporting surface. Analysis of the center of pressure is common in studies on human postural control and gait.
Centroid of a triangle. In mathematics and physics, the centroid, also known as geometric center or center of figure, of a plane figure or solid figure is the arithmetic mean position of all the points in the surface of the figure.