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Verhulst Pierre: more detail

Traité Élémentaire Des Fonctions Elliptiques; Ouvrage Destiné a Faire Suite Aux Traités Élémentaires De Calcul Intégral... (French Edition) by Pierre François Verhulst, 2010-01-12
VERHULST, PIERRE-FRANÇOIS: An entry from Macmillan Reference USA's <i>Encyclopedia of Population</i> by R. Lesthaeghe, 2003
Mathématicien Belge: Luc de Brabandere, Adolphe Quetelet, Adrien Romain, Joseph Delbeuf, Eugène Charles Catalan, Pierre François Verhulst (French Edition)
Companion To Modern And Contemporary Art, A by Christiane Berndes, Anna Hakkens, et all 2003-04-02
The Logistic Map and the Route to Chaos: From the Beginnings to Modern Applications (Understanding Complex Systems)

lists with details

Verhulst
Biography of pierre verhulst (18041849) pierre verhulst was educated inBrussels, then in 1822 he entered the University of Ghent.
http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Verhulst.html

Extractions: Version for printing Pierre Verhulst was educated in Brussels, then in 1822 he entered the University of Ghent. He received his doctorate in 1825 after only three years study and returned to Brussels. There he worked on the theory of numbers, and, influenced by Quetelet , he became interested in social statistics. He had been intending to publish the complete works of Euler but he became more and more interested in social statistics. In 1829 Verhulst published a translation of John Herschel 's Theory of light. However he became ill and decided to travel to Italy in the hope that his health would improve. In 1830 Verhulst arrived in Rome. However his visit there was not a quiet one. Quetelet wrote:- Whilst on a trip to Rome he conceived the idea of carrying out reform in the Papal States and of persuading the Holy Father to give a constitution to his people. This plan did not meet with approval and Verhulst was ordered to leave Rome. He returned to Belgium.
References For Verhulst
References for the biography of pierre verhulst. References for pierre verhulst.Biography in Dictionary of Scientific Biography (New York 19701990).
http://www-groups.dcs.st-and.ac.uk/~history/Printref/Verhulst.html
Verhulst, Pierre-Francois (1804-1849) -- From Eric Weisstein's World Of Scientif
Quetelet, A. pierreFrançois verhulst. in Sciences Mathématiques et Physiqueschez les Belges au commencement du XIX siècle.
http://scienceworld.wolfram.com/biography/Verhulst.html

Extractions: This entry contributed by Margherita Barile Belgian mathematician who introduced the Verhulst equation (also known as the logistic equation ) to model human population growth in 1838. He quit his literary studies to devote himself to mathematics. As an undergraduate at the University of Ghent, he was awarded two academic prizes for his works on the calculus of variations Later, he published papers on number theory and physics. The Belgian revolution of 1830 and the invasion of his country by the Dutch army in 1831 partially diverted his attention from abstract research. His political initiatives failed, nonetheless he could pursue his interests for social issues as a mathematician and a teacher. His interest in probability theory had been triggered by a new lottery game, but he soon applied it to political economy and later to demographical studies, a field that was rapidly developing due to Malthus' theory and the increasing use of statistics in human sciences. Verhulst, however, opposed any attempt to apply mathematical models to ethical judgement. His main work is
Lexikon Pierre-FranÃ§ois Verhulst
pierre-François verhulst aus der
http://lexikon.freenet.de/Pierre-FranÃ§ois_Verhulst

Extractions: Sie sind hier: Startseite Lexikon Pierre-Fran§ois Verhulst Pierre-Fran§ois Verhulst 28. Oktober in Br¼ssel 15. Februar in Br¼ssel) war ein belgischer Mathematiker. Er ist heute vor allem als Entdecker der logistischen Gleichung bekannt. Pierre-Fran§ois Verhulst Verhulst begann zun¤chst in Br¼ssel Klassische Philologie zu studieren, wandte sich dann aber dem Studium der Mathematik in Gent zu, wo er 1825 promovierte. Als Student erhielt er zwei Preise f¼r seine Arbeiten zur Variationsrechnung . Sp¤ter ver¶ffentlichte er Artikel im Bereich der Zahlentheorie und der Physik Verhulst war zeitweilig sehr politisch engagiert. So versuchte er bei einem Aufenthalt in Rom 1830 den Papst davon zu ¼berzeugen, dem
Logistic Function: Information From Answers.com
The verhulst equation, (1), was first published by pierre F. verhulst in 1838after he had read Thomas Malthus Essay on the Principle of Population.
http://www.answers.com/topic/logistic-function

Extractions: showHide_TellMeAbout2('false'); Business Entertainment Games Health ... More... On this page: Wikipedia Best of Web Mentioned In Or search: - The Web - Images - News - Blogs - Shopping logistic function Wikipedia logistic function The logistic function or logistic curve models the S-curve of growth of some set P. The initial stage of growth is approximately exponential; then, as competition arises, the growth slows, and at maturity, growth stops. As shown below , the untrammeled growth can be modelled as a rate term +rKP (a percentage of P). But then, as the population grows, some members of P (modelled as r P ) interfere with each other in competition for some critical resource (which can be called the bottleneck , modelled by K). This competition diminishes the growth rate, until the set P ceases to grow (this is called maturity The logistic function is defined by the mathematical formula: for real parameters a m n , and . These functions are found in a range of fields, from biology to economics For example, in the development of a baby, a fertilized ovum splits, and the cell count grows: 1, 2, 4, 8, 16, 32, 64, etc. This is exponential growth. But the baby can grow only as large as the uterus can hold; thus other factors start slowing down the increase in the cell count, and the rate of growth slows (but the baby is still growing, of course). After a suitable time, the baby is born, and the child keeps growing. Ultimately, the cell count is stable; the person's height is constant; the growth has stopped, at maturity.
Genealogy Data
verhulst, Augustinus Birth 13 DEC 1898 Erembodegem Death 14 NOV 1995 AalstParents Verleysen, Jeanpierre Parents. Father Verleysen, Arceen
http://users.skynet.be/meertgenealogy/erembodegem/dat357.htm
List Of Scientists By Field
Translate this page Verantius, Faustus. Verdet, Marcel Émile. verhulst, pierre-François. verhulst,pierre-François. Vernadsky, Vladímir Ivanovich. Vernadsky, Vladímir Ivanovich
http://www.indiana.edu/~newdsb/v.html

Extractions: Vagner, Egor Egorovich Vailati, Giovanni Vailati, Giovanni Valenciennes, Achille Valentin, Gabriel Gustav Valentin, Gabriel Gustav Valentine, Basil Valentine, Basil Valerio, Luca Vallisnieri, Antonio Vallisnieri, Antonio Valmont de Bomare, Jacques- Christophe Valmont de Bomare, Jacques- Christophe Valsalva, Anton Maria Valsalva, Anton Maria Valturio, Roberto Valturio, Roberto Valverde, Juan de Valverde, Juan de Van de Graaff, Robert Jemison Van Hise, Charles Richard Van Leckwijck, William Van Slyke, Donald Dexter Van Slyke, Donald Dexter Van Vleck, John Hasbrouck Van Vleck, John Hasbrouck Vandiver, Harry Schultz Vanini, Giulio Cesare Van't Hoff, Jacobus Henricus Vanuxem, Lardner Varenius, Bernhardus Varignon, Pierre Varignon, Pierre Varolio, Costanzo Varro, Marcus Terentius Varro, Marcus Terentius Vassale, Giulio Vastarini-Cresi, Giovanni Vastarini-Cresi, Giovanni Vauquelin, Nicolas Louis Vavilov, Nikolay Ivanovich Vavilov, Sergey Ivanovich Veblen, Oswald Vegard, Lars Vegard, Lars Veksler, Vladimir Iosifovich Veksler, Vladimir Iosifovich Venetz, Ignatz
Social Sciences
Translate this page Themistius. Thurnam, John. Townsend, Joseph. Tunstall, Cuthbert. Turgot,Anne-Robert-Jacques. verhulst, pierre-François. Virchow, Rudolf Carl
http://www.indiana.edu/~newdsb/socsci.html

Extractions: Social Sciences Ameghino, Florentino Antiphon Anuchin, Dmitrii Nikolaevich Aristotle Baer, Karl Ernst von Bain, Alexander Banister, John Barton, Benjamin Smith Becher, Johann Joachim Beckmann, Johann Bekhterev, Vladimir Mikhailovich Bernheim, Hippolyte Binet, Alfred Black, Davidson Blanc, Alberto-Carlo Blumenbach, Johann Friedrich Boas, Franz Broca, Pierre Paul Busk, George Camper, Peter Cattell, James McKeen Coghill, George Ellett Engels, Friedrich Fabbroni, Giovanni Valentino Mattia Fechner, Gustav Theodor Fraipont, Julien Frazer, James George Freud, Sigmund Fritsch, Gustav Theodor Gall, Franz Joseph Galton, Francis Garnot, Prosper Gesell, Arnold Lucius Gratiolet, Louis Pierre Graunt, John Gua de Malves, Jean Paul Hall, Granville Stanley Harper, Roland McMillan Hartley, David Hartlib, Samuel Herbart, Johann Friedrich Hering, Karl Ewald Konstantin Herrick, Charles Judson Hobbes, Thomas Hoeven, Jan van der Horsley, Victor Alexander Haden Hume, David Hunt, James Huxley, Thomas Henry James, William Jefferson, Thomas Jevons, William Stanley Jung, Carl Gustav
History Of Astronomy: Persons (V)
verhulst, pierre Francois (18041849). Short biography and references (MacTutorHist. Math.) Verne, Jules (1828-1905). Short biography and references From
http://www.astro.uni-bonn.de/~pbrosche/persons/pers_v.html

Extractions: Vali, Hojatollah (20th c.) Valier, Max (1895-1930) Van Allen, James Alfred (b. 1914) van den Bergh, Sidney (b. 1929) van de Hulst, Hendrik Christoffel (1918-2000) van de Kamp, Peter (1901-1995) Van Heeck, Johannes (1574-16?) Van Vleck, Edward Burr (1863-1943) Vassenius: see Wassenius, Birger (1687-1771)
Population Dynamics -- Facts, Info, And Encyclopedia Article
Gompertz) Benjamin Gompertz and (Click link for more info and facts aboutpierre François verhulst) pierre François verhulst in the early 19th century,
http://www.absoluteastronomy.com/encyclopedia/P/Po/Population_dynamics.htm

Extractions: Population dynamics is the study of marginal and long-term changes in the numbers, individual weights and age composition of individuals in one or several ((statistics) the entire aggregation of items from which samples can be drawn) population s, and (Click link for more info and facts about biological) biological and (The area in which something exists or lives) environment al processes influencing those changes. Population dynamics is the dominant branch of (Click link for more info and facts about mathematical biology) mathematical biology , which has a history of more than 200 years. The early period was dominated by (A statistic characterizing human populations (or segments of human populations broken down by age or sex or income etc.)) demographic studies such as the work of (Click link for more info and facts about Benjamin Gompertz) Benjamin Gompertz and (Click link for more info and facts about Pierre François Verhulst) Pierre François Verhulst in the early 19th century, who refined and adjusted the
Logistic Function -- Facts, Info, And Encyclopedia Article
The verhulst equation, (1), was first published by pierre F. verhulst in 1838after he had read (An English economist who argued that increases in
http://www.absoluteastronomy.com/encyclopedia/l/lo/logistic_function.htm

Extractions: As shown below, the untrammeled growth can be modelled as a rate term +rKP (a percentage of P). But then, as the population grows, some members of P (modelled as ) interfere with each other in competition for some critical resource (which can be called the bottleneck , modelled by K). This competition diminishes the growth rate, until the set P ceases to grow (this is called maturity The logistic function is defined by the mathematical formula: For example, in the development of a baby, a fertilized ovum splits, and the cell count grows: 1, 2, 4, 8, 16, 32, 64, etc. This is exponential growth. But the baby can grow only as large as the uterus can hold; thus other factors start slowing down the increase in the cell count, and the rate of growth slows (but the baby is still growing, of course). After a suitable time, the baby is born, and the child keeps growing. Ultimately, the cell count is stable; the person's height is constant; the growth has stopped, at maturity.
Population Dynamics
The verhulst Model, named after pierreFrancois verhulst (1804-1849) of Belgium,improved upon the exponential growth model of Malthus by incorporating a
http://entropy.brneurosci.org/population.html

Extractions: Population growth can be calculated by a number of mathematical models. The two simplest models are the Malthusian, or exponential model, and the Verhulst, or logistic model. The Verhulst Model, named after Pierre-Francois Verhulst (1804-1849) of Belgium, improved upon the exponential growth model of Malthus by incorporating a limiting population value that the environment can support. Above this value, lack of food or other resources causes the death rate to rise so that it equals the birth rate. It does not account for oscillations that may occur when food runs out suddenly, but is otherwise quite accurate, and has been shown to give a close match to real populations. The Malthusian equation assumes that population growth is proportional to the current population. x'(t) = bx(t) where b is the net growth rate per unit time and x is the population. This integrates to the familiar exponential x(t) = x * exp(bt) In the Verhulst model, competition occurs among individuals when they encounter other members of the population. This adds a quadratic term to account for the interactions between pairs of people, changing the differential equation to x'(t) = bx(t) - dx where b and d are unknown constants. After integration (which is left as an exercise for the reader to carry out on some rainy day) we get
Population Dynamics Study Gompertz Verhulst General Formulation
Population Dynamics Study Gompertz verhulst General Formulation Economy. July 1865) and pierre François verhulst ( 28 October 1804 15 February 1849),
http://www.economicexpert.com/a/Population:dynamics.html

Extractions: var GLB_RIS='http://www.economicexpert.com';var GLB_RIR='/cincshared/external';var GLB_MMS='http://www.economicexpert.com';var GLB_MIR='/site/image';GLB_MML='/'; document.write(''); document.write(''); document.write(''); document.write(''); A1('s',':','html'); Non User A B C ... Population dynamics is the study of marginal and long term changes in the numbers, individual weights and age composition of individuals in one or several population s, and biological and environmental processes influencing those changes. Population dynamics is the dominant branch of mathematical biology , which has a history of more than 200 years. The early period was dominated by demographic studies such as the work of Benjamin Gompertz 5 March 14 July ) and Pierre François Verhulst 28 October 15 February ), who refined and adjusted the Malthusian demograhical model. A more general model formulation was proposed by F.J. Richards in Events January-February January 1 Cultivars of plants named after this date must be named in a modern language, not in Latin. January 1 Cuba: Fulgencio Batista flees Havana when forces of Fidel Castro advance January 2 CBS Radio cuts four soap operas: Bac , by which the models of Gompertz, Verhulst and also Ludwig von Bertalanffy Karl Ludwig von Bertalanffy ( September_19, 1901, Vienna, Austria June_12, 1972, New York, USA) was a biologist who was a founder of general systems theory. An Austrian citizen, he did much work in the United States. However, he experienced discrimination
Boom And Bust Mathematics
The founder of population mathematics was pierre verhulst (18041849), a verytalented Belgian mathematician dogged by poor health throughout his short life
http://www.unc.edu/depts/cmse/math/Verhulst.html

Extractions: Boom and Bust Mathematics It's the summer of 1997: rabies is devastating rabies populations in the Triangle. Although this troubling disease certainly seems like something out of the ordinary, the mathematics predicts that wild swings in populations are possible even in the most normal of times. The mathematics involved is amazingly simple. The founder of population mathematics was Pierre Verhulst (1804-1849), a very talented Belgian mathematician dogged by poor health throughout his short life. Prior to his work, the famous British economist Robert Malthus had predicted that animal and human populations were fated to grow exponentially. But Verhulst understood that real populations are capped: in every habitat and for every species there is a carrying capacity . A population exceeding this capacity must go down rather than up. Verhulst reasoned something like this. Let's write p(n) for the population in year n and let M be the carrying capacity. The population grows at a rate g, a certain percentage per year, as animals are born or wander into the area. (For big, long-lived species like humans g will be small, like 5%, but for most small, short-lived animals it will be much larger, usually more than 100%.) The population grows every year by gp(n) animals.
Untitled Document
The logistic model was developed by Belgian mathematician pierre verhulst (1838) who Before we move on to illustrate verhulst s model, we first must
http://jwilson.coe.uga.edu/EMT668/EMAT4680.2000/Laws.Casey/EMAT4690/VerhulstMode

Extractions: Verhulst Model of Population Growth (Note: This essay could also be used as a lesson on modeling logistic function) The logistic model was developed by Belgian mathematician Pierre Verhulst (1838) who suggested that the rate of population increase may be limited, i.e., it may depend on population density R=Ro(1-n/k) Before we move on to illustrate Verhulst's model, we first must understand the dynamics of the population. Population growth rate declines with population numbers, N, and reaches when N = K. Parameter K is the upper limit of population growth and it is called carrying capacity. It is usually interpreted as the amount of resources expressed in the number of organisms that can be supported by these resources. If population numbers exceed K, then population growth rate becomes negative and population numbers decline. The dynamics of the population is described by the differential equation: To illustrate this, we could form a simulation to explore how population is effected and how we can model the logistic function by Verhulst. Description of Simulation: t.
SWiSH [recensioni1.swi]
verhulst s book is modest, subtle, nonpoliticaloften simply referring tocomplex debates, Guy Bois, verhulst, and pierre Toubert were put on display.
http://www.storiamedievale2.net/Biblioteca/recensioni-v.htm

Extractions: histoire de mentalite , as 'night' represents much more in cultural and historical terms than simply the change from daylight to darkness. Light, an all-pervasive feature of modern culture, was not an automatic given in the Middle Ages. To have light at night represented advanced cultural development and financial wealth. Peasants, for instance, or regular workers, went to bed after the sun had set, and rose again at the crack of dawn. Today, electricity has changed all that, and nightlife is just as important as day life in many respects. When electricity fails, however, modern life quickly comes to a standstill. Man's instinctual fear of sudden darkness indicates the cultural significance of night at all times, and history can actually be written by focusing on human responses to night and darkness. These basic observations make Night in the Middle Ages an interesting study.
Why Logistic Ogive And Not Autocatalytic Curve?, J Linacre
18, Art. 1, 145, 1845), pierre Francois verhulst (1804-1849), verhulstwrites We will give the name logistic logistique to the curve (1845 p.8)
http://www.rasch.org/rmt/rmt64k.htm

Extractions: Why logistic ogive and not autocatalytic curve?, J Linacre We call our S-shaped response curve a logistic ogive. How did this term originate? S-shaped curves are also called sigmoid curves, from the Greek "s", sigma. In his "Mathematical Researches into the Law of Population Growth Increase" (Nouveaux Memoires de l'Academie Royale des Sciences et Belles-Lettres de Bruxelles, 18, Art. 1, 1-45, 1845), Pierre Francois Verhulst (1804-1849), Professor of Analysis at the Belgian Military College, examines population growth in Belgium. He discovers that sigmoid curves are useful for describing population growth. Following Malthus, Verhulst hypothesizes that small populations increase geometrically, because the supply of resources exceeds demand. Then, as supply and demand balance, population growth is constant. Finally, as demand exceeds supply, population growth decreases at the same rate that it had increased. Verhulst describes this process with an equation that enables him to predict when a population will reach any given size (see Verhulst's Figure): t = log10( p/ ( m/n - p ) ) / m where, for Belgium, with 1830 population of 4,247,113
X-next (Verhulst) Logistic Equation
known the verhulst model after pierreFrancois verhulst, 1804-1849, The fact that verhulst published it sometime between 1838 and 1850 tells us
http://www.jmu.edu/geology/evolutionarysystems/programs/xnext.shtml

Extractions: Updated: 02/07/2003 Download the X-next Program ; Xnext = rX (1-X). Read a description of the model and how it works (pdf file). See typical outcomes of the model at different values of r (pdf file) Experiment With and Explore Xnext a laboratory guide used in the course; it will help someone systematically explore some of the properties of the model (18 page pdf file). An Introduction to Chaotic Systems - an excellent introduction to the logistic equation, with a very clever applet of the bifurcation diagram Read Wolfram's Math World mathematical description of this equation The Xnext equation is also known the Verhulst model [after Pierre-Francois Verhulst, 1804-1849], and the logistic equation. It also serves as a definition of chaos, in the mathematical sense. Actually, it is not the equation itself, but its iterated behavior at high values of r that defines chaos. The fact that Verhulst published it sometime between 1838 and 1850 tells us the idea existed long before chaos theory became a formal study. Logistic equations are ones that are iterated (calculated over and over), recursive (output of the last calculation is input for the next), and normalized (population size ranges from zero - extinction - to one - maximum conceivable population).
Rombout Verhulst (1624 - 1698) Artwork Images, Exhibitions, Reviews
Rombout verhulst Rombout verhulst moved to Amsterdam in 1646 where he began working Click here to buy Renoir, pierreAuguste Mademoiselle Irene for $6
http://wwar.com/masters/v/verhulst-rombout.html

Extractions: Rombout Verhulst moved to Amsterdam in 1646 where he began working under Flemish sculptor Artus Quellinus. After Quellinus left for Antwerp, Verhulst became the Netherlandss most prominent sculptor. He moved to Leiden and then The Hague, working for a small group of leading citizens. He produced portrait busts and effigies in a naturalistic sense that was different from the classical style of his colleagues.
Articles - Pierre FranÃ§ois Verhulst
the terms of the GNU Free Documentation License Source Original text fromthe article in Wikipedia, The Free Encyclopedia pierre Fran§ois verhulst.
http://www.centralairconditioners.net/articles/Pierre_FranÃ§ois_Verhulst

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