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{{about|the ancient mathematician|the modern politician|Liu Hui (politician)}}
Obesity is the second name of over fat. When a person cross the limit of fat according to his height plus age called OBESE. But description and limit of obesity is different according to age plus height. Obesity is a body disorder which results inside deform  the body. But there is a differance in healthy body plus fat body. A health body is in the wise shape, But an fat body is deformed by different parts of body like Tummy , Hips,Arms and legs.<br><br>The target fat should nonetheless be the weight based on the standard BMI height and fat charts. The range presented in the [http://safedietplansforwomen.com/bmi-chart bmi chart] is fair, and even with muscle mass plus a large body frame, ladies ought to be able to reach the healthy range. Moreover, women are permitted to be a small heavier as they grow elder.<br><br>Excessive body fat increases the risks for many main bmi chart men wellness problems. Body Mass Index is a quick-and-dirty measure of overweight (plus underweight). But it's not the number one quickie system. The Larry Index is much more realistic.<br><br>Lets state an adult male is 60 plus weighs 200 pounds. According for this chart, his BMI will be 27.1, that puts him into the obese category. If he loses 17 pounds, the same guy, today at 183 pounds, would have a BMI of 24.8, that would put him in the normal fat category.<br><br>The perfect weight for females of the medium frame measuring 64-67 inches is between 124-147 pounds. This leads to a lot of difference inside what will be considered an ideal weight. Women could be accorded for each inch over 5 feet (1.52 m). So a female that is 52 (1.57m) has an ideal weight of 110 pounds (49.89 kg).<br><br>Example 1: A healthy, normally-proportioned 5-foot-tall person bmi chart women weighs 100 pounds. What would we expect a 6-foot-tall person to weigh according to BMI?<br><br>To make certain that all these measurements are exact, we want to be in .5 a centimeter, or a .25 centimeter, when possible. Men plus ladies measure different parts of their body.<br><br>Unfortunately far too many children have considerably more body fat then that, and you, because adults plus their parents, are failing them. They will likely not thank us in years to come for failing them inside this method. Dont blame the overweight child. Blame the parent, if there is any blame. Some is due to genetics or illness, yet just a relatively surprisingly little amount.
{{Infobox Three Kingdoms biography
| name       = Liu Hui
| image      =
| image_size  =
| caption    =
| Title      = Mathematician
| Kingdom    = Cao Wei
| birth_date  =  220
| birth_place = [[Zibo]]
| death_date  =
| death_place =
| Simp        = 刘徽
| Trad        = 劉徽
| Pinyin      = Liú Huī
| WG          = Liu Hui
| Zi          =
| Post        =
}}
{{ChineseText}}
{{Chinese-name|[[Liu]]}}
 
'''Liu Hui''' (fl. 3rd century) was one of the greatest mathematicians of ancient China. He lived in the state of [[Cao Wei]] during the [[Three Kingdoms]] period of [[History of China|Chinese history]]. In 263, he edited and published a book with solutions to mathematical problems presented in the famous Chinese book of mathematics known as ''[[The Nine Chapters on the Mathematical Art]]''.
 
He was a descendant of the Marquis of Zixiang of the [[Han dynasty]], corresponding to current Zixiang township of [[Shandong]] province. He completed his commentary to the ''Nine Chapters'' in the year 263.
 
He probably visited [[Luoyang]], and measured the sun's shadow.
 
==Mathematical work==
Along with [[Zu Chongzhi]] (429–500), Liu Hui was known as one of the greatest mathematicians of ancient China.<ref>Needham, Volume 3, 85-86</ref> Liu Hui expressed all of his mathematical results in the form of decimal fractions (using [[Metrology|metrological]] units), yet the later [[Yang Hui]] (c. 1238-1298 AD) expressed his mathematical results in full decimal expressions.<ref>Needham, Volume 3, 46.</ref><ref>Needham, Volume 3, 85.</ref>
 
Liu provided commentary on a mathematical proof identical to the [[Pythagorean theorem]].<ref>Needham, Volume 3, 22.</ref> Liu called the figure of the drawn diagram for the theorem the "diagram giving the relations between the hypotenuse and the sum and difference of the other two sides whereby one can find the unknown from the known".<ref>Needham, Volume 3, 95-96.</ref>
 
In the field of plane areas and solid figures, Liu Hui was one of the greatest contributors to [[empirical]] solid geometry. For example, he found that a [[Wedge (geometry)|wedge]] with rectangular base and both sides sloping could be broken down into a pyramid and a [[tetrahedral]] wedge.<ref>Needham, Volume 3, 98-99.</ref> He also found that a wedge with [[trapezoid]] base and both sides sloping could be made to give two tetrahedral wedges separated by a pyramid. In his commentaries on the ''Nine Chapters'', he presented:
 
* An algorithm for calculation of [[pi]] ({{pi}}) in the comments to chapter 1.<ref>Needham, Volume 3, 66.</ref> He calculated pi to <math>3.141024 < \pi < 3.142074</math> with a 192 (= 64 × 3) sided [[polygon]]. Archimedes used a circumscribed 96-polygon to obtain the inequality <math>\pi <\tfrac{22}{7}</math>, and then used an inscribed 96-gon to obtain the inequality <math>\tfrac{223}{71} < \pi </math>. Liu Hui used only one inscribed 96-gon to obtain his {{pi}} inequalily, and his results were a bit more accurate than Archimedes'.<ref>Needham, Volume 3, 100-101.</ref> But he commented that 3.142074 was too large, and picked the first three digits of {{pi}}  =  3.141024 ~3.14 and put it in fraction form <math>\pi = \tfrac{157}{50}</math>. He later invented a [[Liu Hui's pi algorithm#Quick method|quick method]] and obtained <math>\pi =3.1416</math>, which he checked with a 3072-gon(3072 = 512 × 6). [[The Nine Chapters on the Mathematical Art|Nine Chapters]] had used the value 3 for {{pi}}, but [[Zhang Heng]] (78-139 AD) had previously estimated pi to the square root of 10.
* [[Gaussian elimination]].
* [[Cavalieri's principle]] to find the volume of a cylinder,<ref>Needham, Volume 3, 143.</ref> although this work was only finished by [[Zu Gengzhi]]. Liu's commentaries often include explanations why some methods work and why others do not. Although his commentary was a great contribution, some answers had slight errors which was later corrected by the [[Tang Dynasty|Tang]] mathematician and Taoist believer [[Li Chunfeng]].
[[File:Sea island survey.jpg|thumb|right|200px|Survey of sea island]]
Liu Hui also presented, in a separate appendix of 263 AD called ''Haidao suanjing'' or ''[[The Sea Island Mathematical Manual]]'', several problems related to [[surveying]]. This book contained many practical problems of geometry, including the measurement of the heights of [[Chinese pagoda]] towers.<ref>Needham, Volume 3, 30.</ref> This smaller work outlined instructions on how to measure distances and heights with "tall surveyor's poles and horizontal bars fixed at right angles to them".<ref>Needham, Volume 3, 31.</ref> With this, the following cases are considered in his work:
 
* The measurement of the height of an island opposed to its [[sea level]] and viewed from the sea
* The height of a tree on a hill
* The size of a city wall viewed at a long distance
* The depth of a [[ravine]] (using hence-forward cross-bars)
* The height of a tower on a plain seen from a hill
* The breadth of a river-mouth seen from a distance on land
* The depth of a [[transparency (optics)|transparent]] pool
* The width of a river as seen from a hill
* The size of a city seen from a mountain.
 
Liu Hui's information about surveying was known to his contemporaries as well. The [[History of cartography|cartographer]] and state minister [[Pei Xiu]] (224–271) outlined the advancements of cartography, surveying, and mathematics up until his time. This included the first use of a [[Grid reference|rectangular grid and graduated scale]] for accurate measurement of distances on representative terrain maps.<ref>Hsu, 90–96.</ref> Liu Hui provided commentary on the Nine Chapter's problems involving building [[canal]] and river [[Dike (construction)|dykes]], giving results for total amount of materials used, the amount of labor needed, the amount of time needed for construction, etc.<ref>Needham, Volume 4, Part 3, 331.</ref>  
 
Although translated into English long beforehand, Liu's work was translated into [[French language|French]] by Guo Shuchun, a professor from the [[Chinese Academy of Sciences]], who began in 1985 and took twenty years to complete his translation.
 
==See also==
*[[List of people of the Three Kingdoms]]
*[[Liu Hui's π algorithm]]
*[[The Sea Island Mathematical Manual]]
*[[History of mathematics]]
*[[History of geometry]]
*[[Chinese mathematics]]
 
==Notes==
{{reflist}}
 
==References==
*Chen, Stephen. "Changing Faces:  Unveiling a Masterpiece of Ancient Logical Thinking." ''[[South China Morning Post]]'', Sunday, January 28, 2007.
*Guo, Shuchun, [http://203.72.198.245/web/Content.asp?ID=43261&Query=1 "Liu Hui"]. ''[[Encyclopedia of China]]'' (Mathematics Edition), 1st ed.
*Hsu, Mei-ling. "The Qin Maps: A Clue to Later Chinese Cartographic Development," ''Imago Mundi'' (Volume 45, 1993): 90-100.
* Needham, Joseph & C. Cullen (Eds.) (1959). ''Science and Civilisation in China: Volume III'', section 19. Cambridge University Press. ISBN 0-521-05801-5.
*Needham, Joseph (1986). ''Science and Civilization in China: Volume 3, Mathematics and the Sciences of the Heavens and the Earth''. Taipei: Caves Books, Ltd.
*Needham, Joseph (1986). ''Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 3, Civil Engineering and Nautics''. Taipei: Caves Books Ltd.
*Ho Peng Yoke: Liu Hui, Dictionary of Scientific Biography
*Yoshio Mikami: Development of Mathematics in China and Japan.
*Crossley, J.M et al., The Logic of Liu Hui and Euclid, Philosophy and History of Science, vol 3, No 1, 1994 this bo chen
 
==External links==
*[http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Liu_Hui.html Liu Hui at MacTutor]
*[http://www.jstor.org/pss/2691200  Liu Hui and the first Golden Age of Chinese Mathematics,by Philip D. Straffin Jr]
 
{{People of Cao Wei}}
 
{{DEFAULTSORT:Liu, Hui}}
[[Category:Ancient Chinese mathematicians]]
[[Category:People of Cao Wei]]
[[Category:3rd-century Chinese people]]
[[Category:People from Zibo]]
[[Category:Scientists from Shandong]]

Latest revision as of 01:55, 27 October 2014

Obesity is the second name of over fat. When a person cross the limit of fat according to his height plus age called OBESE. But description and limit of obesity is different according to age plus height. Obesity is a body disorder which results inside deform the body. But there is a differance in healthy body plus fat body. A health body is in the wise shape, But an fat body is deformed by different parts of body like Tummy , Hips,Arms and legs.

The target fat should nonetheless be the weight based on the standard BMI height and fat charts. The range presented in the bmi chart is fair, and even with muscle mass plus a large body frame, ladies ought to be able to reach the healthy range. Moreover, women are permitted to be a small heavier as they grow elder.

Excessive body fat increases the risks for many main bmi chart men wellness problems. Body Mass Index is a quick-and-dirty measure of overweight (plus underweight). But it's not the number one quickie system. The Larry Index is much more realistic.

Lets state an adult male is 60 plus weighs 200 pounds. According for this chart, his BMI will be 27.1, that puts him into the obese category. If he loses 17 pounds, the same guy, today at 183 pounds, would have a BMI of 24.8, that would put him in the normal fat category.

The perfect weight for females of the medium frame measuring 64-67 inches is between 124-147 pounds. This leads to a lot of difference inside what will be considered an ideal weight. Women could be accorded for each inch over 5 feet (1.52 m). So a female that is 52 (1.57m) has an ideal weight of 110 pounds (49.89 kg).

Example 1: A healthy, normally-proportioned 5-foot-tall person bmi chart women weighs 100 pounds. What would we expect a 6-foot-tall person to weigh according to BMI?

To make certain that all these measurements are exact, we want to be in .5 a centimeter, or a .25 centimeter, when possible. Men plus ladies measure different parts of their body.

Unfortunately far too many children have considerably more body fat then that, and you, because adults plus their parents, are failing them. They will likely not thank us in years to come for failing them inside this method. Dont blame the overweight child. Blame the parent, if there is any blame. Some is due to genetics or illness, yet just a relatively surprisingly little amount.