text:
Talk:Maximum power transfer theorem

impedance matching is not for Maximum Power Transfer at all
This should be merged with impedance matching. - Omegatron 14:38, Jul 29, 2004 (UTC)

I would keep Impedance Matching separated from Maximum Power Transfer Theorem (Jacobi's theorem)

1. Impedance Matching has more to do with camouflage than anything else. For example, if you split an infinit transmission line but do not want the source generator, which feeds that line, to notice that the line is not infinit anymore, one should conceal the line interruption with a device, in this case a resistance equal to Zo (the transmission line characteristic impedance). Someone decided to call this Impedance Matching just because this is obtained by matching the source and load impedances. Incidentally, this happens when there is maximum power transfer. Doing impedance matching, is a way to hide from the signal traveling in the transmission line that that line is not infinit at all. Using analogy, this is exactly what many other creatures (chamaeleon) happen to do to conceal themselves or something, that is Camouflage. Thus, if a transmission line is not infinite but a camouflage impedance can be add to its end, a signal is going to enter smoothily and without return into the device loading the line. That's the same someone driving a car on a long straight motorway would do if they could not tell if the road is infinite or terminated with a nice billboard with a giant paint simulating an extension of the road. Impedance Matching tell what to do to obtain camouflage.

2. The Maximum Power Transfer theorem, as stated by Jacobi, should be well understood not to indicate how to get maximum power transfer but how to obtain maximum efficiency.

3. There is one great example in which Maximum Power Transfer is essencial, i.e. Nyquist theorem, which models thermal noise generated by a resistor. The power generated by thermal noise is proportional to absolute temperature (T) and system bandwidth, Bw. The Boltzman constant completes the equation, i.e. P = k T Bw, where P is the power generated internally in a Resistor, T is the temperature and Bw is the badwidth of the measuring system or amplifier. If the Resistor (a component) is modelled by a Thevenin equivalente circuit, i.e. a noise voltage generator with Vth and Rth (voltage source and its impedance) feeding a matched load impedance R = Rth, results in Maximum power transfer, giving: kTBw = Vth^2/(4Rth). From which the Nyquist equation results as Vth^2 = 4 k T Bw R.

4. In most cases, if not all, one should avoid associating MAximum Power Transfer Theorem with Impedance Matching and threfore avoid very common mistakes and misunderstandings.

Commentator: Anisio R. Braga/ DAEE/CEFETMG/Brazil

"Incidentally, this happens when there is maximum power transfer."

 * They are the same thing, though, right? I understand that you are saying the purposes are different.  Can you give more info about how the "impedance matching theorem" was first conceived, if it originally had nothing to do with the max power theroem? - Omegatron 18:52, May 13, 2005 (UTC)

 * Here's the historical view. According to Wikipedia, Moritz von Jacobi developed the maximum power theorem between 1837 and 1839 while working on battery-powered electric boats.

 * Impedance matching for transmission lines originated in the telephone industry, to prevent audible echoes. (Aside: The typical impedance of early telephone lines, which were air-spaced pairs, was 600 ohms, a value that was then copied by the broadcasting industry.) Several Web sources mention the Bell company as the discoverer of this technique. According to James Calvert, the impedance-matching autotransformer was invented by Emil Berliner of Bell and patented on 4 June 1877 as the Bell-Berliner System and first used in 1879 (document in Library of Congress archives). The purpose of Berliner's invention (which he called an induction apparatus) was to match the impedances of the transmitter and receiver to each other, which looks to me like an application of the MPT; it seems that he, like everybody else at that time, was unaware of the need to match the tx/rx unit to the transmission line, although fortuitously his device did that too.

 * Load coils, first used by Mihajlo Pupin around 1896 but based on earlier work by Oliver Heaviside, were added to long lines to make their impedance more uniform. This, I think, was the true beginning of impedance matching of transmission lines based on a sound theory of electrical impedances.

 * Conclusion: the MPT was developed first. I can't find a causal link between this and Heaviside's work. There must have been a huge amount of discovery going on in the intervening period, so any link between the two discoveries is likely to be an extremely diffuse one. --Heron 20:44, 13 May 2005 (UTC)

 * Hmmm... So several different implementations of the same thing were developed for different reasons?  I still think they should be part of the same article, with clarification of Anisio's concerns, since most people will think they are the same and won't see the other article. - Omegatron 21:47, May 13, 2005 (UTC)

 * Not so fast. ;-) I've just found an online textbook (Electromagnetic Waves and Antennas, Rutgers University) that refers to two types of impedance matching: complex conjugate matching and reflectionless matching (see the first two pages of Chapter 11). It states that the first concept is equivalent to the maximum power theorem (Zload = Zsource*, where * means complex conjugate), and the second, not surprisingly, is to prevent reflections (Zload = Zsource). You will notice that these two equations are not equivalent. I'm afraid haven't got time right now to digest the book and explain why they are different, but the equations are all there if you want them. I may try to get my head round this in the next few days. --Heron 22:27, 13 May 2005 (UTC)

Excellent Talk Contribution
Yes! Good source, Heron! For derivation of conjugate impedance matching see also chapters 13 and 16, especially:

https://www.ece.rutgers.edu/~orfanidi/ewa/ch16.pdf (for other chapters, change chapter number 16).
 *  Sophocles J. Orfanidis, Electromagnetic Waves and Antennas , ECE Department, Rutgers University. 2016, ch.16.4 “Antenna Equivalent Circuits”,

p. 750, eq. (7.4.4), $$ \Gamma_{gen} = \frac {Z_A - {Z_G}^*} {Z_A + Z_G} $$

p. 751, eq. (7.4.7), $$ \Gamma_{load} = \frac {Z_L - {Z_A}^*} {Z_L + Z_A} $$

In Wikipedia articles please try to use unmistakable, descriptive words.

For Conjugate impedance matching and reflectionless impedance matching we have different matching types, goals, concepts, given quantities, physics phenomena, and thus also different coefficient equations, that correctly describe the respective case.

Please do not use ambigous names alone like reflection coefficient or unindexed quantities like $$\Gamma$$ without descriptive indication or indexing of what exactly is meant in a given case.

Orfanidis avoided an ambigous name. That was much wiser than most others that described conjugate imperdance match using a name that included reflection. (I can provide many sources.)

The historically first published source, showing (like Orfanidis) the difference and including the derivation of conjugate matching, probably is:

 * Shepard Roberts, ,Conjugate-image impedances, Member I.R.E,

https://worldradiohistory.com/hd2/IDX-Site-Technical/Engineering-General/Archive-IRE-IDX/IDX/10s/IRE-1946-04-OCR-Page-0081.pdf

Proceedings of the I.R.E. and Waves and Electrons, volume 34, number 4, Section 1, April 1946

p.199 P, eq. (3a) “reflection coefficient” (by analogy) $$ \alpha_{10} = \frac {Z_1 - {Z_0}^*} {Z_1 + Z_0} $$, Fig. 1-Equivalent circuit of generator and load

It shows the difference between reflectionless matching (that is characterized there as being on the usual image basis and conjugate impedance matching, that is characterized there as on a conjugate image basis.

Please note the little, but important difference he used for the name of the coefficient: The quotation marks: "reflection coefficient" and the addition (by analogy) versus reflection coefficient (without quotation marks, and without addition).

These distinguishing differences were ambigously ignored later, and this resulted even in standard glossary of ATIS (reflection coefficient) and IEC (equation for return loss, that includes the reflection coefficient implicitely) being falsely misleading to the (nowhere proven by derivation) assumption that the indeed different reflection coefficients be the same in some undefined broader sense.

https://glossary.atis.org/glossary/reflection-coefficient-rc/?char=R&page_number=all&sort=ASC

https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=702-07-25

DJ7BA (talk) 15:28, 16 June 2022 (UTC)

 * Oh! Well that little asterisk is a huge difference. - Omegatron 22:33, May 13, 2005 (UTC)

Oliver Heaviside (See Oliver Heaviside: The Life, Work, and Times of an Electrical Genius of the Victorian Age by Paul J. Nahin) is to be credited with the Matching Impedance idea, something Oliver discovered around 1880's. By the way, Heaviside was the guy who coined the terms Impedance and helped us all, without complicated math's (operational calculus) to solve dynamical circuits using algebraic equations in the frequency domain (i.e. in the complex domain). Nowadays it is understood that systems of all kinds, e.g. hydraulic, Thermal, pneumatic, besides electric, requires Matching generalized impedance to avoid reflections. For example, a soil pressure cell should have the same soil impedance (mechanical stiffiness) to avoid reflections of pressure waves. That has nothing to do with MTP but a lot to do with Matching Impedance, which I preffer to call system camouflage. (Anisio)

 * I started to clarify the differences and split up the attentions of both articles, but they still need a lot of work. - Omegatron 17:44, May 22, 2005 (UTC)

--

Omegatron, when you wrote:
 * (though typically, more of an impedance bridging connection is used, to maximize control of the cone and lower distortion).

were you referring to valve amplifiers or to transistor amplifiers? I thought that valve amplifiers were an example of where transformers were used to match the hi-Z output to the low-Z speaker, but I could have been wrong. I can see the relevance of your statement to solid-state amplifiers - if that is what you meant, then please let me know and I will make it clearer in the text. Thanks. --Heron 22:52, 9 July 2005 (UTC) P.S. Thanks for spotting my equal/opposite reactance mistake - oops!

 * Yes, that's for transistor amps. I don't know much about tube amps, but this paper says:
 * "Older valve amplifiers needed a different form of impedance matching, because output valves generally had a fairly fixed and relatively high output impedance, so they couldn?t deliver audio energy efficiently into the low load impedance of a typical speaker. So an output transformer had to be used, to produce a closer impedance match. The transformer ?stepped up? the impedance of the speaker, so that it gave the output valve an effective load of a few thousand ohms; this was at least comparable with the valve?s own output impedance, so only a small amount of energy was wasted as heat in the valve." - Omegatron 05:09, August 13, 2005 (UTC)

Does it make Sense Now?
Rewritten most of intro. Can people say whether it now makes adequate sense to them?Light current 01:14, 14 August 2005 (UTC)

I'm sorry, I just don't understand one thing : if you augmented the internal resistance of the generator with something useful such as light bulbs than couldn't you augment efficiency too ? If you were to make additional internal resistance to the generator useful then you could get more power for the other components couldn't you ? I doubt I just discovered a miracle theory to make 100 per cent efficiency, there's something I didn't understand I just can't see what. Stevenjlm (talk) 17:20, 8 April 2008 (UTC)

I came by 16 years later and was chastised for trying to apply the theorem in reverse: using the load resistance to calculate the required source resistance. I applied a "citation needed" tag. In my application (trying to do a NiMH conversion of a scooter) I am concerned I will destroy the motor (in a locked rotor condition) if I don't artificially increase the source resistance. Once the motor starts spinning, the load resistance will increase dramatically due to back EMF (which is what we want for efficiency). 107.190.70.111 (talk) 03:48, 26 July 2021 (UTC) I think MPTT may actually apply in my application as a first approximation, assuming the load and source can dissipate about the same amount of power (details matter). In a temporary fault condition (locked rotor) it may be beneficial to have the load and source dissipate the same amount of power for safety reasons (A circuit breaker will trip if fault persists in my example).107.190.70.111 (talk) 18:52, 26 July 2021 (UTC) Update: Looks like the (commercial off the shelf) motor controller will regulate current on it's own, without regard to battery chemistry. 107.190.70.111 (talk) 01:26, 27 July 2021 (UTC)

Jacobis Theorem
I dont think the description of Jabobis theorem is totally correct yet. Will attempt to fix later.Light current 11:08, 14 August 2005 (UTC)
 * WE seem only to have one reference to this theorem being called 'Jacobis' theorem. I personally have never heard it called this, neither is Jacobi mentioned in any of my books as the originator of this theoerm. Does anyone have any more evidence that it was in fact Professor Jacobi' theorem?? Light current 21:39, 14 August 2005 (UTC)
 * Google search "Jacobi's theorem power". Note that there are two Jacobi's theorems.  This is one, and the other is over here: Skew-symmetric matrix.  - Omegatron 22:46, August 14, 2005 (UTC)
 * Yes thats correct. I have seen the link but all references to Jacobis Max power theorem stem from a single web article (His biographical notes). Is it safe to assume the validity of this single article? Light current 23:10, 14 August 2005 (UTC)
 * Can you link to that article? - Omegatron 23:19, August 14, 2005 (UTC)
 * Nice clean up job there 'O'. Not sure what you mean. I am able to link to it but I dont think the link goes directly the biography. Or did you mean 'could I put the correct link into the article'?? Light current 02:55, 15 August 2005 (UTC)
 * I just meant "you said 'all references to Jacobis Max power theorem stem from a single web article'. what is that article?" - Omegatron 03:06, August 15, 2005 (UTC)
 * Its here Light current 03:17, 15 August 2005 (UTC)
 * Yeah, I found that, too. Looks like we need to recruit a Russian to check out the sources for us. - Omegatron 03:26, August 15, 2005 (UTC)
 * I have looked through the references, the reference http://www.kurierweb.com/81-100(2)/90(190)kurier/articles/academic.htm does not work (the site looks like an e-zine, there only latest issue is available). The other three references have nice biography of Jacobi but no mention of the theorem.
 * On the other hand simple search on "maximal power theorem" and Jacobi brings 132 google references, among them http://www.absoluteastronomy.com/encyclopedia/m/ma/maximum_power_theorem.htm http://web.linix.ca/pedia/index.php/Maximum_power_theorem

http://www.electro.patent-invent.com/electricity/inventions/maximum_power_theorem.html http://www.in2reach.com/cgi-bin/readzip.cgi?%22//m/ma/maximum_power_theorem.html%22 etc.

 * Those are just mirrors of this article! :-) - Omegatron 05:59, August 15, 2005 (UTC)
 * Yep, they are verly close and many refer to Wikipedia. But 136 mirrors, wow!

I've read your links and there's no mention of any theorem or such. The articles give some info on Jacobi's researches in the field of electromagnetism in partnership with Heinrich Lenz, but he's mostly attributed for his works in galvanoplastics (Electroplating).

I think someone confused him with his brother Carl Gustav Jakob Jacobi who researched rational mechanics and invented Hamilton-Jacobi theory, studied by math students. He is most known for his Jacobi's theorem and it's the only meaning of the name known in Russia, contrary to what the article says (see search results on the web portal of Ministry of Education).

Yes there's a maximum power transfer rule in Russian physics courses, known as согласование нагрузки, but it's derived as a general rule from the formula for electromotive force that takes into account internal resistance of a cell or a generator. There's no mention of the theorem in physics courses for high education. --DmitryKo 16:07, 15 August 2005 (UTC)
 * Oh Dear!! Does this mean we will have to remove the ref to Jacobi from this page??Light current 16:22, 15 August 2005 (UTC)
 * I think calling it Jacobi's theorem is simply confusing people and may not even be correct (according to the view of our Russian user). Why dont we delete ref to Jacobi to play safe?Light current 23:52, 15 August 2005 (UTC)

 * We shouldn't delete it, but explain the origin of the term. It seems a lot of websites talk about him, so if it's not true, we should say so in this article.  User:Heron started the article.  We can start with him. ;-) - Omegatron 23:57, August 15, 2005 (UTC)
 * Sorry . my last edit comment should have read 'fraternal' not 'filial'. Im forgetting my LatinLight current 00:10, 16 August 2005 (UTC)

All right, all right. I admit I started the Jacobi thing. I had never heard it called Jacobi's Law until I read James Calvert's article, and I was convinced because it seemed to be corroborated by the biography that you mentioned above. If you want me to sort it out, then my solution will be to remove the reference to Jacobi until we find some proof. It's only a couple of sentences, so it will be easy to reinstate later. --Heron 19:55, 16 August 2005 (UTC)

Ooh, ooh, I just found a reference to Jacobi's theorem that seems to be independent of Wikipedia and the sources we have already mentioned. It's here, on the Oregon Public Education Network, and claims to be based on a Dictionary For The Electrician with Formulas, Tom Henry, Copyright 1997 (a later edition is ISBN 0945495099). All we have to do is find the electrician with formulas, and ask to see his dictionary. --Heron 20:17, 19 August 2005 (UTC)

PFC
"Power factor correction(where an inductive reactance is used to "balance out" a capacitive one), is essentially the same idea as conjugate impedance matching although it is done for entirely different reasons."

 * How is it "essentially the same idea"? - Omegatron 23:13, August 18, 2005 (UTC)
 * Makes the over all impedance look resistive and hence near to unity PF Light current 23:39, 18 August 2005 (UTC)

RE Merge: Ecological application of maximum power as a principle of energetics
There has been something of a hoo haa over my article on Maximum power. Some have suggested that it be merged with this article. The maximum power article was meant to document the use of maximum power in ecology by H.T.Odum, who considered maximum power the 4th principle of energetics (following on from the first 4 laws of thermodynamics). I suggest that this article be merged with the maximum power article including the history of the development of the theorem, together with a section applications such as those in systems ecology, and biology for example. Also...this article current could do with some more specific and authoritative references. Sholto Maud 07:31, 2 December 2005 (UTC) Post script: I also added the table and graph to try and demonstrate the concept of maximum powe efficiency more effectively.

I suggest that the Maximum power article be renamed to Maximum power principle and this article on Max power theorem be left un-altered. A short redirect page under Maximum power could point to both and clear the confusion. They have absolutle nothing to do with each other. --Pfafrich 22:49, 30 December 2005 (UTC)

 * Don't merge. That article is about something completely different (though I'm not sure what, exactly...) — Omegatron 23:44, 30 December 2005 (UTC)

RE Maximising power transfer versus power efficiency
Does the maximum power transfer theorem apply when we convert from the electrical form of energy into the mechanical form of energy? That is, does maximum power transfer only apply when we restrict the power transfer to the electrical form of energy, and NOT when we are converting from electrical to other forms of energy like mechanical, heat, light etc.? It seems to me that the article has some confusion about this point. Sholto Maud 02:19, 3 May 2006 (UTC)

 * The maximum power theorem is about altering the load impedance to obtain maximum power at the load (not maximum efficiency). Converting from one form of power to another is concerned with efficiency. — Omegatron 13:46, 3 May 2006 (UTC)

Agreed. Maximum power theorem is not about maximum efficiency. However the article states that the theorem can be "sidestepped". What does this mean to sidestep a theorem? Is it that the theorem does not apply in cases where energy is converted from one form to another? Further discussion about analogous application of the theorem in mechanical systems is currently taking place on impedance matching talk. Sholto Maud 03:14, 4 May 2006 (UTC)

 * The only meaning I can think of for "sidestepping" a theorem is violating the assumptions of the theorem. For instance, Earnshaw's theorem conclusively proves that there is no way to stably levitate an object using classical unmoving magnets.  It is certainly possible to levitate things, though, and it's done by using moving magnets or diamagnets. — Omegatron 23:37, 4 May 2006 (UTC)

Rename article
I believe "Maximum power transfer theorem" is the more common name for this theorem. I propose renaming the article accordingly. -Roger (talk) 19:54, 18 January 2009 (UTC)

 * Correct: I was taught it as the 'Maximum power transfer theorem'.  I have even taught it as the 'Maximum power transfer theorem'.  Every electrical text book that I have used refers to it as the 'Maximum power transfer theorem'.  Ergo, the article name is cutrrently incorrect.  Sadly, I don't know how to rename an article, otherwise I would do it. 86.179.167.116 (talk) 16:08, 22 December 2010 (UTC)

Something does not make sense in the equation with multiplying by RL and RS. I think they get switched by accident too early. —Preceding unsigned comment added by 139.140.167.192 (talk) 10:38, 28 October 2010 (UTC)

 * What does that have to do with renaming the article? 86.179.167.116 (talk) 16:08, 22 December 2010 (UTC)
 * Renamed, using the confusingly-named "move" button; oh well, we're all used to clicking on "start" to shutdown a computer. --Wtshymanski (talk) 16:31, 22 December 2010 (UTC)

 * What 'Move' button would that be? I don't seem to have one. 86.179.167.116 (talk) 15:21, 26 December 2010 (UTC)

The step by step through the equation has a problem.
When we decide to only find the minimum of the denominator, RL gets put in the denominator of R^2 when it should be in the numerator. When we switch everything, then RL goes in the denominator (which we have right). —Preceding unsigned comment added by 139.140.167.192 (talk) 10:44, 28 October 2010 (UTC)

Maximum power transfer for current source
My suggestion is to also include the equivalent circuit and equations for maximum power transfer if source is a pure current source (Norton equivalent circuit). 128.104.199.64 (talk) 18:09, 19 October 2012 (UTC)

Merging MPPT and power optmizer
These are just other names for variations of devices that present itself to the power source as a resistance value that provides the most power transfer. Instead of wasting our research effort on redundant information, I suggest we combine them so that we can consolidate all the good stuff. I also have some materials I researched and added to solar inverter and solar micro inverter. I am thinking combining all of the discussion that has to do with V/I conversion device here and move solar specific discussions to one of PV articles. thoughts? Cantaloupe2 (talk) 06:51, 2 September 2013 (UTC)
 * Well first off, the article on power transfer is related to this one, but certainly not the "same thing" by any definition or stretch of the imagination. Moreover, an optimizer may or may not use MPPT, the Tigo is a counterexample. I really don't see any logic behind this merge. If there's too much duplication of content between the articles we can fix that, but merging them is wrong. Maury Markowitz (talk) 12:16, 11 April 2014 (UTC)
 * 'Oppose merge - theorem is not the same as hardware. We wouldn't merge Ohm's law and resistor, either. --Wtshymanski (talk) 13:36, 11 April 2014 (UTC)
 * Just because you opppose (sic) the merge, that does not give you the right to delete the merge tag from the article. Especially as you left the tags on the two source articles.  Once this discussion has run its course and there is a reasonable concensus, then the merge can be closed.  And unlike you, someone else will probably do it correctly. DieSwartzPunkt (talk) 14:35, 11 April 2014 (UTC)
 * I have cleaned up the stale tags on the other articles. --Wtshymanski (talk) 16:10, 11 April 2014 (UTC)
 * Oppose: Not sufficiently closely related. DieSwartzPunkt (talk) 14:35, 11 April 2014 (UTC)

The red curve illustrating PL/Pm vs RL/Rs is incorrect
The red curve illustrating PL/Pm vs RL/Rs is incorrect.

The actual PL/Pm vs RL/Rs curve starts at zero and asymptotically approaches 4, with no max or min.

The correct curve, which illustrates max power at RL = Rs, is PL vs RL/Rs. 68.134.89.137 (talk) 15:14, 5 February 2021 (UTC)

 * It is not incorrect, if it is understood, what is meant by Pmax: The maximum available Power from a source having a fixed internal source resistance RS.
 * DJ7BA (talk) 15:51, 16 June 2022 (UTC)

title: Talk:Maximum power transfer theorem


text:
M. S. Bartlett

Maurice Stevenson Bartlett FRS (18 June 1910 – 8 January 2002) was an English statistician who made particular contributions to the analysis of data with spatial and temporal patterns. He is also known for his work in the theory of statistical inference and in multivariate analysis.

Biography
Born in London, Bartlett was raised in a poor family but won a scholarship to Latymer Upper School in Hammersmith, where he was inspired to the study of statistics by a chapter in Hall and Knight's Algebra. In 1929, he won a scholarship to Queens' College, Cambridge where he read mathematics, graduating with the rank of wrangler. He attended lectures on statistics by John Wishart, on relativity by Arthur Eddington and on quantum mechanics by Paul Dirac. In one of his lectures Wishart described his geometric derivation of the Wishart distribution. Overnight Bartlett worked out a proof using characteristic functions. Bartlett was Wishart's first post-graduate student and they wrote two papers together. This was the beginning of Bartlett's involvement with multivariate analysis. During his Queens years, he rowed for the college.

In 1933, Bartlett was recruited by Egon Pearson to the new statistics department at University College, London. Pearson was already working with Jerzy Neyman. Also in the college were Ronald A. Fisher and J. B. S. Haldane. Bartlett was stimulated by all of them, most of all by the work of Fisher, criticising some of it (for example, fiducial inference) while developing other parts (for example conditional inference). Relations between the two men fluctuated; sometimes Bartlett was in Fisher's good books, but often not. In 1934, Bartlett became statistician at the Imperial Chemical Industries (ICI) agricultural research station at Jealott's Hill. Not only did he deal with practical problems but he worked on statistical theory, as well as on problems in genetics but he became interested in the characterisation of intelligence. He remembered Jealott's Hill as the best working environment of his career. Bartlett left ICI for the University of Cambridge in 1938 but at the outset of World War II was mobilised into the Ministry of Supply, conducting rocket research alongside Frank Anscombe, David Kendall and Pat Moran.

After the war Bartlett's renewed Cambridge work focused on time-series analysis and stochastic process. With Jo Moyal he planned a large book on probability, but the collaboration did not work out and Bartlett went ahead and published his own book on stochastic processes. He made a number of visits to the United States. In 1947 he became professor of mathematical statistics at the School of Mathematics at the University of Manchester where he not only developed his interests in epidemiology but also served as an able and active administrator. In 1960, he took up the chair of statistics at University College, London before serving the last eight years of his academic life as professor of biomathematics at the University of Oxford. He retired in 1975.

After his retirement Bartlett remained active in statistics, visiting the Institute of Advanced Studies at the Australian National University several times. He had married Sheila, daughter of C. E. Chapman, in 1957, the couple parenting a daughter. Bartlett died in Exmouth, Devon.

Bartlett is known for Bartlett's method for estimating power spectra and Bartlett's test for homoscedasticity.

Honours

 * Rayleigh Prize, (1933);
 * Guy Medals in Silver (1952) and Gold (1969) of the Royal Statistical Society;
 * President of the Manchester Statistical Society, (1959–1960);
 * Fellow of the Royal Society, (1961);
 * President of the Royal Statistical Society (1966);
 * Honorary Member of the International Statistical Institute, (1980);
 * Foreign Associate of the U.S. National Academy of Sciences, (1993);
 * D.Sc.s from the University of Chicago (1966) and the University of Hull (1976).

Books

 * An Introduction to Stochastic Processes, (1955) ISBN 0-521-04116-3
 * Stochastic Population Models in Ecology and Epidemiology, (1960) ISBN 0-416-52330-7
 * Essays in Probability and Statistics, (1962) ISBN 0-416-64880-0
 * Probability, Statistics and Time, (1975) ISBN 0-412-14150-7
 * The Statistical Analysis of Spatial Pattern, (1976) ISBN 0-412-14290-2
 * Selected Papers of M. S. Bartlett 3 vols. edited by R.G. Stanton, E.D. Johnson, D.S. Meek. Winnipeg : Charles Babbage Research Centre (1989).
 * Selected Papers of M. S. Bartlett 3 vols. edited by R.G. Stanton, E.D. Johnson, D.S. Meek. Winnipeg : Charles Babbage Research Centre (1989).

Selected papers

 * (1933) with John Wishart, The distribution of second order moment statistics in a normal system. Proc. Camb. Philos. Soc. 28, 455–459.
 * (1933) On the theory of statistical regression. Proc. Royal Soc. Edinburgh, 53, 260–283.
 * (1933) Probability and chance in the theory of statistics. Proc. Royal Soc. Lond. A 141 518–534.
 * (1934) The vector representation of a sample. Proc. Camb. Philos. Soc., 30, 327–340.
 * (1936) Statistical information and properties of sufficiency. Proc. Royal Soc. Lond. A 154, 124–137.
 * (1937) Properties of sufficiency and statistical tests. Proc. Royal Soc. Lond. A, 160, 268–282. (reprinted with an introduction by D. A. S. Fraser S. Kotz & N. L. Johnson (eds) Breakthroughs in Statistics, volume 1. Springer, New York. 1992.)
 * (1938) Methods of estimating mental factors. Nature, 141, 609–610.
 * (1939) A note on tests of significance in multivariate analysis, in Proceedings of the Cambridge Philosophical Society
 * (1941) The statistical significance of canonical correlation. Biometrika.
 * (1947) The use of transformations. Biometrics.
 * (1948) Internal and external factor analysis. British Journal of Psychiatry.
 * (1949) Fitting a straight line when both variables are subjects to error. Biometrics.
 * (1949) The statistical significance of "dispersed hits" in card-guessing experiments. Proceedings of the Society for Psychical Research, 48, 336–338.
 * (1950) Tests of significance in multivariate analysis. British Journal of Mathematical and Statistical Psychology.
 * (1950) Tests of significance in factor analysis. British Journal of Psychology, 3, 77–85.

Autobiography
Several statisticians, including Bartlett, give their life stories.
 * Ingram Olkin (1989) A Conversation with Maurice Bartlett, Statistical Science, 4, 151–163.
 * "Chance and Change" in J. Gani (ed) (1982) The Making of Statisticians, New York: Springer-Verlag.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: M. S. Bartlett


text:
Jackson Beck

Jackson Beck (July 23, 1912 – July 28, 2004) was an American actor best known as the announcer on radio's The Adventures of Superman and the voice of Bluto in the Famous era Popeye theatrical shorts.

Early years
Beck was born on July 23, 1912, in New York City. Beck's father, Max Beck, was a silent film actor.

Radio
Beck's early radio experience included work at WINS and WHN, both in New York City. Beginning in 1931, he worked on Myrt and Marge, among other roles. In 1934, he was the announcer for The Adventures of Babe Ruth on the radio. In 1943, he took over as narrator of radio's The Adventures of Superman; it was Beck who intoned the familiar prologue "strange visitor from another planet..." He also had recurring roles, voicing an occasional tough guy and also portraying Beany Martin, the Daily Planet's teenage copy boy. On Superman episodes featuring Batman, he played Bruce Wayne's butler, Alfred Beagle.

He also impersonated Joseph Stalin and other world leaders for The March of Time radio series, starred as The Cisco Kid on radio from 1942 to 1945 and sleuth Philo Vance in a syndicated series from 1948 to 1950, starred in the dramatic anthology Brownstone Theater on Mutual, and served as narrator for the radio adventures of Tom Corbett, Space Cadet.

Beck also co-starred in several episodes of the CBS Radio Mystery Theater.

Television
Beck portrayed Perry White, Clark Kent's boss in Filmation's The New Adventures of Superman animated series and was narrator as well. He was the announcer for the first season of Tom Corbett, Space Cadet on television.

Film
In 1966, Beck dubbed the English voice of the judge listing Tuco's many crimes before sentencing him to death by hanging in The Good, the Bad and the Ugly, and used his deep, dramatic, modulated voice as the narrator of Woody Allen's Take the Money and Run in 1969. He also narrated the cult comedy film Cry Uncle! in 1971, and was one of the players in National Lampoon's first comedy album Radio Dinner in 1972. He was prominent as well in Allen's 1987 film Radio Days, dubbing the voice of the on-the-spot newsman.

Animation
Beck had a prolific career in animation, becoming one of the regular voice actors at Famous Studios in the mid-1940s. He voiced Bluto in the Popeye cartoons, Little Lulu's father, the fox in the Baby Huey cartoons, and Buzzy the Crow, who was a foil for Katnip the Cat in a number of cartoons. Beck used a black dialect for the voice of Buzzy. He was also the voice of King Leonardo in the 1960s TV cartoon series of the same name. He also had a part in the Peanuts 1977 film Race for Your Life, Charlie Brown as the snickering cat, Brutus. He narrated the 1980s G.I. Joe animated TV series. His other voice work included network TV promos (he did a series of promos for NBC's NFL coverage for much of the 1980s), narration for sketches on Saturday Night Live, movie trailers, and commercials for everything from toys to shampoo (one of Beck's very last commercials was for Infusium Shampoo).

Other work
Beck also served as a pitchman for products from Combat Roach Killer to Little Caesars Pizza (he was Caesar, Jr.) In 1999, he narrated a dramatization of L. Ron Hubbard's Dr. Methuselah for NPR's radio series 2000X. Beck also did few onscreen acting roles. A notable one was as mobster Willie Saffire in the crime-based daytime soap opera The Edge of Night from 1968 to 1969.

Beck was featured announcer on the 1972 comedy record album "National Lampoon Radio Dinner".

Beck had also done some voice work for MTV. Mostly for contest advertisements.

Beck also recorded voices for children's records such as The Little Engine That Could from Diplomat Records.

In 1994, Beck voiced Darrel the Fifth Fish, Hunter #2, Wickersham Guard #2, the Sneetches and Greedy Ape in Storybook Weaver, and later in 2004, remade as Storybook Weaver Deluxe (his last voice).

Death
Beck died of a stroke on July 28, 2004, five days after his 92nd birthday. He is buried in Brooklyn's Mount Hope Cemetery.

title: Jackson Beck


text:
User talk:Jeff.oneill

Hello and welcome to Wikipedia! Hope you like it here, and stick around.

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Single Transferable Vote
Hey, you made an edit saying that 22 cities have used STV in America. Does this include multimember STV, or just cities using instant runoff like San Francisco? Can you provide a source (I'd like to read more)? Thanks! Scott Ritchie 21:22, 2 September 2005 (UTC)

title: User talk:Jeff.oneill


text:
Talk:Time–frequency representation

Whoever created this page did a nice job. Solid information and well written. jeffo 14:50, 29 Jul 2004 (UTC)

Examples, formulas, and perhaps sample images would be of benefit. The article in its current form seems to appeal mostly to people already familiar with the subject. A good start, though. Rethunk 20:06, 8 Jun 2005 (UTC)

 * I wrote this page. Thanks. I put a lot of time and effort into writing a thorough introduction to the subject in [http:// www.ffconsultancy.com/free/thesis.pdf my PhD thesis]. I also contributed significantly to research in this area (see the Hilbert-Hermitian wavelet) and commercialized my work in the form of [http:// www.ffconsultancy.com/products/CWT/ a Mathematica add-on]. If you want to do time-frequency analysis accurately, the maths gets very hard very quickly. So I'm not sure it belongs on Wikipedia. Maybe a cutdown version based on Gabor/Morlet would be ok. Jon Harrop 13:31, 15 April 2007 (UTC)

Empty Set
If I am not mistaken, the set $$\mathcal{C}$$ in the paragraph named Quadratic forms is always convex as it is always empty. I do not the correct version of this statement, I am guessing that it should read something like If for every $$T \in [0, E_0]$$ the set $$\{ (t, f) \in \mathbb{R}^2 : |E(t, f)| > T \}$$ is convex, then the QTFR $$E(t, f)$$ is cross-term free.

46.142.36.29 (talk) 22:48, 21 June 2014 (UTC)

Yea, I agree, the set $$\{ (t,f)\in \mathbb{R}^2 : |E(t,f)|>T,\,\forall T\in[0, E_0] \}$$ is always empty since $$|E(t,f)| \leq E_0 = \sup E(t,f)$$. I don't know what the correct version is, and I wasn't able to find it in Jon Harrop's thesis, but I think your suggestion of pulling the "for every $$T \in [0, E_0]$$" out of the set comprehension is the most sensible thing to do. -- Tuckerleavitt (talk) 01:54, 25 September 2017 (UTC)

title: Talk:Time–frequency representation


text:
Wang Chongyang

Wang Chongyang (11 January 1113 – 22 January 1170; Chinese calendar: 22nd day, 12th month, 2nd year, Zhenghe era in the reign of Emperor Huizong of Song - 4th day, 1st month, 10th year, Dading era in the reign of Emperor Shizong of Jin) was a Chinese philosopher and poet. He was a Taoist master and one of the founders of the Quanzhen School in the 12th century during the Jin dynasty (1115–1234). He was one of the Five Northern Patriarchs of Quanzhen. He also appears as a character in works of wuxia fiction.

Name

 * Family name: Wang (王)
 * Given names: Zhongfu (中孚); Dewei (德威); Zhe (喆)
 * Courtesy names: Yunqing (允卿); Shixiong (世雄); Zhiming (知明)
 * Pseudonym: Chongyangzi (重陽子)

Life
Wang was born with his birth name as "Zhongfu" in a wealthy family in 1113. He was educated in Chinese classics and martial arts.

Wang intended to start a rebellion against the Jurchen-led Jin dynasty, which conquered northern China in the Jin–Song Wars. According to tradition, in the summer of 1159 when he was 48, he met three Taoist immortals in a tavern, Zhongli Quan, Lü Dongbin, and Liu Haichan. They trained him in secret forms of Taoism. He changed his name to "Zhe" and adopted the Taoist name "Chongyang".

In 1160, Wang met one of the immortals again and was provided with a set of written instructions called "Ganshui Xianyuan Lu". Those written instructions included the names of two men who would later become his disciples (Ma Yu and Tan Chuduan). Wang built a tomb for himself near Mount Zhongnan and called it "Tomb of the Living Dead". He lived in it for three years.

At the end of the three years, Wang filled the tomb with earth and built a hut on top of it and called it "Complete Perfection Hut". He spent the next four years in the hut studying Taoism and imparting his knowledge to others. During that time, he met Tan Chuduan, who became his disciple after he cured Tan from illness. Qiu Chuji and Tan traveled around the local towns and villages with Wang and founded five Taoist congregations. Wang's teachings were referred to the "Teachings of the Complete Perfection" (after the hut) and his branch of Taoism became known as the Quanzhen School.

In 1167, Wang burnt down the hut and travelled east to Shandong, where he met Ma Yu and Ma's wife, Sun Bu'er. They became his disciples as well. He accepted a total of seven disciples who later became known as "Seven Masters of Quanzhen" or "Seven Elders of Quanzhen". They are also called the "Seven Immortals" or "Seven Perfected Beings".

In 1187, Emperor Shizong of Jin summoned Wang's disciple Wang Chuyi (and, according to some sources, also Qiu Chuji) to preach in his inner palace. Later, he requested the presence of Wang Chuyi at his deathbed. Shizong's successor, Emperor Zhangzong, banned the teaching of Quanzhen Taoism. He considered them as causing heretical and detrimental to society; He converted to Quanzhen's teachings later and let Wang Chuyi stay in Yanjing (present-day Beijing) for a year. Shizong's grandson Wanyan Shou later wrote a biography for Wang Chongyang.

He was immortalized in the Longmen Grottoes.

Writings
Wang was the author of many poems of Taoist instruction. According to legend, Liu Chuxuan became a follower of Wang after reading one of Wang's poems.

Wang's writings include:
 * "An Anthology of Complete Perfection by Chongyang" (Chongyang Quanzhen Ji)
 * "Chongyang's Anthology on Teaching Transformation" (Chongyang Jiaohua Ji)
 * "Chongyang's Anthology of the Ten Transformations by Dividing Pears" (Chongyang fenli shihua ji) (The phrase "to divide a pear" is a pun for "to separate," these were writings intended to convince Ma Yu and Sun Bu'er to separate in order to better cultivate the Dao.)

Disciples

The most notable ones among Wang's seven disciples were Sun Bu'er and Qiu Chuji. Sun's husband, Ma Yu, was one of the seven, while she became an important role model for female Taoists. Ma Yu later succeeded Wang as the leader of the Quanzhen School.

Qiu Chuji gained the favour of Genghis Khan and founded the White Cloud Monastery in Beijing. Genghis Khan granted tax-exempt status to all Quanzhen schools and placed Qiu in charge of all religions in China.

Each of the seven disciples founded his or her own lineage of Quanzhen Taoism. They are as follows:
 * 1) Ma Yu (馬鈺) founded the Yuxian lineage (Meeting the Immortals)
 * 2) Tan Chuduan (譚處端) founded the Nanwu lineage (Southern Void)
 * 3) Liu Chuxuan (劉處玄) founded the Suishan lineage (Mount Sui)
 * 4) Qiu Chuji (丘處機) founded the Longmen lineage (Dragon Gate)
 * 5) Wang Chuyi (王處一) founded the Yushan lineage (Mount Yu)
 * 6) Hao Datong (郝大通) founded the Huashan lineage (Mount Hua)
 * 7) Sun Bu'er (孫不二) founded the Qingjing lineage (Clarity and Stillness)

Condor Trilogy
Wang Chongyang is mentioned by name in the wuxia novels The Legend of the Condor Heroes and The Return of the Condor Heroes by Jin Yong. He is already dead when the events in the first novel take place and the details of his life are revealed by other characters, such as his junior Zhou Botong. Wang Chongyang, who was nicknamed "Central Divine", emerged as one of the top five martial artists in the jianghu (martial artists' community) in his time after a martial arts contest on Mount Hua. He also founded the martial arts school Quanzhen School, which is based on the real-life Quanzhen School. After his death, his seven apprentices succeed him and lead Quanzhen to become one of the major orthodox martial arts schools in the jianghu.

In the second novel, the protagonists Yang Guo and Xiaolongnü discover more details about Wang Chongyang's life in the Ancient Tomb on Mount Zhongnan, where the Quanzhen School is based. It is revealed that Wang Chongyang had a romantic relationship with Lin Chaoying, the founder of the Ancient Tomb School, which Xiaolongnü and Yang Guo are members of. Wang Chongyang had lost to Lin Chaoying in a contest and had to keep his promise to hand over possession of the tomb and lead a monastic life as a Taoist for the rest of his life.

Other appearances
In the manhua series Oriental Heroes by Hong Kong artist Wong Yuk-long, Wang Chongyang is noted as the creator of the 'Nine Solar Art'.

title: Wang Chongyang


text:
User talk:Hhofuentes

RE:Changes to Image:Escudo_armas_Panama.png
Really? I dind't now that; I will revert my edit.  I € ₣  18:27, 31 January 2008 (UTC)

title: User talk:Hhofuentes


text:
Talk:Medium-chain acyl-coenzyme A dehydrogenase deficiency

Moved from the original page
The present page is:
 * written from the perspective of a paediatric pathologist, largely intended for parents and other family members who have experience of Sudden Unexpected Death in Infancy. I hope the biochemistry will be checked and refined by biochemists

I know absolutely nothing about this, but I've moved it from MCAD, which now redirects here, as I don't believe pages should be titled by acronyms (with AIDS as one possible exception). JFW | T@lk  14:49, 29 Jul 2004 (UTC)

MCAD vs MCADD typography
I take the view that MCAD should always be in italics to avoid confusion with MCADD the condition. This would avoid some visual confusion in the article, yet would alter the existing typography the least.

Eyreland (talk)

My experience
I know a baby with MCADD. She was diagnosed via a routine blood test shortly after she was born. That possibility isn't mentioned in this article, and that's the only change I can think of. Any time she's not keeping food down, she needs to be taken to an ER and put on a glucose IV - just saline and sugar. No lipids, which are fats which contribute to the problem, and apparently commonly used in IVs - it was the ER doctor's main question the first time this baby went in, answered clearly in the letter from the baby's metabolic specialist to the ER doctors. First time was two nights in the ER, second time was one night. Just kept on the IV until she could keep down food reliably (formula / breast milk). So, while the serious need to get to an ER is certainly exciting, treatment was very straightforward. She's about three months old, and this has happened twice. — Darxus (talk) 18:12, 24 February 2012 (UTC)

Oh, the other issue, which is basically mentioned in the article, is that she needs to be fed very regularly. Every 3 hours for the first couple months.—Darxus (talk) 18:15, 24 February 2012 (UTC)

I am the father of three MCADD children. Our first child died at 3 years 7 months and the autopsy showed up MCADD. Our subsequent children were diagnosed with MCADD from blood tests after they were born. The above information is correct in so far as an IV drip to maintian blood glucose is important treatment. However, families should be aware that ER staff may well not have heard of MCADD and so a letter written by a specialist advising treatment very much speeds up the action required. This is important as it is imperative that young children with MCADD should not be allowed to be in metabolic shock for any length of time. Parents should know that their young and very young children can absorb sugars directly through the roof of their mouth and so even if they are incapacitated a parent's finger dipped in honey can be placed in the child's mouth and blood glucose levels will be increased. Very young children will also suckle on the finger and therefore ingest the sugars further helping blood sugar levels. Ian, New Zealand — Preceding unsigned comment added by 202.37.32.2 (talk) 22:37, 28 March 2012 (UTC)

Rewrite
I just finished and copied over from my user page, a fairly major rewrite of the article. Reliable, secondary sources, and hopefully fairly understandable. Canada Hky (talk) 23:40, 9 June 2012 (UTC)

ICD-10 Code
I have added the ICD-10 Code as per the reference but the connecting link does not seem to work. I cannot detect the problem. I would be glad if somebody can contribute.  D ip ta ns hu Talk 04:28, 27 January 2013 (UTC)


text:
User talk:Theodoranian

Hello and welcome to Wikipedia! Hope you like it here, and stick around.

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Wikimania; Hello there!
Information I need for the scholarship application:
 * Your full name
 * Your nationality (taiwanese?)
 * What city you live in (taipei?)
 * What languages you speak
 * What wikimedia projects you work on
 * Which days you're planning to come. (if you're a programmer, are you coming for part of the hacking days, august 1-4?)

Plese get this information back to me right away!

Cheers, +sj  +  2 July 2005 06:45 (UTC)

I replied on your talk page already. Thanks!--Theodoranian 2 July 2005 07:08 (UTC)
 * Great! +sj  +  2 July 2005 10:22 (UTC)

My revert to your current events edit
Simple. I did not think your edit observed the neutral point of view. NSL E (T+C) at 09:28 UTC (2006-02-28)

 * I'm don't understand Chinese (esp. not Traditional Chinese!) that well despite it being my mother tongue, but I got the gist of your message. I got the bit about you being an admin at the Chinese Wiki. I'm sorry to have reverted you then, as I felt it wasn't NPOV (this was influenced by your userpage simply stating that you are from Taiwan). I apologise fully for my revert. NSL E (T+C) at 10:31 UTC (2006-02-28)

 * I can read Chinese, but in Singapore we're taught Simplified Chinese, not Traditional. NSL E (T+C) at 11:44 UTC (2006-02-28)

SUL
Hi! I saw that you are bureaucrat on zh.wikipedia so I need little help from you about one problem. I tried to manage my global account (SUL) but I could not do that because I realized that there are other accounts with the same name on other wikimedia projects (http://toolserver.org/~vvv/sulutil.php?user=conquistador). All these accounts are inactive, except on the Portugese Wikipedia (en.wikiquote.org, es.wikipedia.org, fr.wikipedia.org, ja.wikipedia.org, nl.wikipedia.org, pl.wikipedia.org, pt.wikipedia.org, tr.wikipedia.org, zh.wikipedia.org). There is one account that was edited and filled with some data. That user has not edited his account since the 21st December 2005, the same day he opened his account. Furthermore, he has made only 5 edits in total. I opened my account on the Croatian Wikipedia on the 3rd May 2005 and I have made 1128 edits since then. According to Help:SUL I have the superior claim on this username, so I am asking you if you could help me in merging these accounts with mine, so I could have global account. Thanking you in advance. --Conquistador (talk) 02:11, 10 January 2009 (UTC)

Unreferenced BLPs
Hello Theodoranian! Thank you for your contributions. I am a bot alerting you that 1 of the articles that you created  is tagged as an Unreferenced Biography of a Living Person. The biographies of living persons policy requires that all personal or potentially controversial information be sourced. In addition, to ensure verifiability, all biographies should be based on reliable sources. If you were to bring this article up to standards, it would greatly help us with the current Category:All_unreferenced_BLPs article backlog. Once the article is adequately referenced, please remove the unreferencedBLP tag. Here is the article:

Thanks!--DASHBot (talk) 19:40, 16 January 2010 (UTC)
 * 1) Shaw-Lan Wang -

Articles for deletion nomination of Shaw-Lan Wang
I have nominated Shaw-Lan Wang, an article that you created, for deletion. I do not think that this article satisfies Wikipedia's criteria for inclusion, and have explained why at Articles for deletion/Shaw-Lan Wang. Your opinions on the matter are welcome at that same discussion page; also, you are welcome to edit the article to address these concerns. Thank you for your time.Please contact me if you're unsure why you received this message. Taiwantaffy (talk) 14:22, 25 July 2010 (UTC)

ArbCom elections are now open!
MediaWiki message delivery (talk) 12:49, 23 November 2015 (UTC)

Proposed deletion of File:Unionsquaresfo.JPG

The file File:Unionsquaresfo.JPG has been proposed for deletion because of the following concern: "Unused, low-res, no obvious use. Better files at c:Category:Union Square, San Francisco."

While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the file's talk page.

Please consider addressing the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and files for discussion allows discussion to reach consensus for deletion. --Minorax «¦talk¦» 04:13, 23 February 2023 (UTC)

title: User talk:Theodoranian


text:
Grand Bend

Grand Bend is a community located on the shores of Lake Huron in Southwestern Ontario, Canada. It is part of the Municipality of Lambton Shores in Lambton County.

History
In the 1830s a group of English and Scottish settlers bought lots from the Canada Company, a land development firm. One of the original settlers, Benjamin Brewster gave his name to the village, Brewster's Mills, after he and his business partner David Smart secured rights to dam the Ausable River and started a sawmill in 1832. The villagers were mainly the families of the millhands and fishermen. Their homesteads were situated on the south side of the present village, but Grand Bend was originally founded and discovered by Frank Salter, who was a very well-known Lake resort owner and country club developer.

For twenty years Brewster existed as an isolated lumbering community. Until the opening of the highway to Goderich in 1850, both people and provisions had to travel by water. Once road connections were complete, the village was no longer solely dependent on the forests for its livelihood and opportunities for new businesses emerged.

Typical of many pioneer communities, the village assumed many different names throughout its history— Brewster's Mills, Websterville, and Sommerville are all recorded. Early French Canadian settlers in the area referred to the present location of the village as "Aux Crochets", 'at the bends'. Grand Bend survived as a name, perhaps because it was the most appropriate— the tight hairpin turn in the original Ausable River where mills were first established.

Noble v Alley
Improved roads and the arrival of the automobile near the turn of the century had the greatest influence on the growth of Grand Bend. Businesses were established to serve visitors and travellers along the highway, and with the beach, "The Bend" became a summer destination. In the 1940s, however, Grand Bend became the centre of a major controversy in the landmark court case of Noble v Alley. Wolf, a London, Ontario merchant, faced court challenges when he purchased property at Beach O'Pines in contravention of a restrictive covenant that prohibited the ownership of lots or cottages by persons of "Jewish, Hebrew, Semitic, Negro or coloured race or blood". The case was finally heard by the Supreme Court of Canada which ruled that the restrictive covenant as constituted was invalid.

Gibbs v Grand Bend
In the late 1980s, a landowner went to the Supreme Court of Ontario seeking a declaration that he was the successor in title to the entire north beach of Grand Bend, amounting to 1.78 ha, by virtue of a land grant given to the Canada Company in 1836. Although successful at trial in 1989, it was overturned at the Ontario Court of Appeal in 1995, which held that, while the beach did not constitute lands reserved to the Crown, the owners had lost ownership to it over the years because of implied dedication and acceptance for public recreational use. As he was required to give the public access to the beach, he subsequently charged parking fees to the visitors and personally cleaned up the beach every night. In 1998 he reached agreement with the province and the village of Grand Bend to sell the property. There was a separate continuing ownership dispute relating to the harbour at the mouth of the Ausable River.

Present day
Grand Bend is home to a variety of stores and eateries. The main strip is the centre of activity in the town, with shopping during the day and night life venues during the evening drawing crowds. The atmosphere of Grand Bend has given the town a reputation of being Florida north. As well as Main Street, Grand Bend acts as a regional cultural centre, boasting art galleries in the town and the Huron Country Playhouse on the outskirts.

The 2021 population of Grand Bend was 3,031. This increases to about 50,000 in the summer months on holiday weekends. The demographic population of Grand Bend is quite diverse. Families owning vacation homes in the adjacent communities of Oakwood Park, Southcott Pines and Beach O' Pines, are from Ontario, Michigan and as far as New York, Florida, Texas and the American west coast. Among these are the Romney family.

The town as well serves as the backdrop of the docu-drama MTV Show Grand Benders, filmed from 2011 to the present and produced by MDF Productions.

The Pinery Provincial Park and the Lambton Heritage Museum are located seven kilometres south of Grand Bend. Also, in the vicinity one can explore a number of 'Gems of Nature' accessible by marked and maintained hiking trails.

Grand Bend Motorplex has a dragstrip that hosts an International Hot Rod Association race and the IHRA Canadian Nationals, Canada's longest running and largest drag race.

title: Grand Bend


text:
Pinery

Pinery may refer to:
 * Pinery Provincial Park in Ontario, Canada
 * Pineapple pit, sometimes referred to as a pinery
 * Pinery Station in Texas
 * Pinery, South Australia, a locality between Mallala and Balaklava

title: Pinery


text:
User talk:BookWorm

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title: User talk:BookWorm


text:
Armed Audio Warfare

Armed Audio Warfare is the second full-length release and first compilation of electronic music group Meat Beat Manifesto. It was originally scheduled as the group's first album for release in May 1988, but the master tapes were damaged in a fire, necessitating the rewriting and recording of the material, which was released as Storm the Studio. Armed Audio Warfare is actually a compilation of unreleased and rare tracks that give an insight as to how that first album may have sounded had it been released as planned.

Composition and background
The album contains rare tracks from, or related to, various releases of the band from its inception to late 1988. According to the liner notes, "Genocide" is a "burnt" remix of "God O.D.", recorded in December 1988. The song is composed of part of the lyrics from "God O.D." but with darker, more industrial instrumentation and a lack of sampling. "Repulsion" is a track previously released on a compilation by Sweatbox, the band's first record label, in May 1988. "Mister President" is a previously unreleased, sample-heavy track recorded in February 1988 with a notable clip from the introduction of Monty Python's Previous Record. The fourth track, "Reanimator", contains significant dub influences. It was to be released as part of the "Re-Animator" single in August 1988, but the single never had a commercial release.

Tracks 5, 6, and 7 are part of the band's first release, the November 1987 Suck Hard EP, as an A-side and two B-sides, respectively. On almost all releases of Armed Audio Warfare, there is a misprint that inverts the titles of tracks 6 and 7. "Kneel and Buzz" has a raw, live sound, plus samples from the communications of the Apollo 11 mission. The title itself is a pun on the names of astronauts Neil (Armstrong) and Buzz (Aldrin). "Fear Version" is a very short, yet intense track recorded in January 1988 that was intended to be on the Suck Hard CD reissue, but the single was subsequently never released in that format. "Give Your Body Its Freedom" is cited, in the liner notes, as the original version of the track "Strap Down (Roar of the Underground)", from the June 1988 single Strap Down. The lengthy song contains live vocals, heavy sampling and distinct sections, including a rather intense buildup and climax contrasted with a calm final minute.

The tenth track, "Marrs Needs Women", is the first of two tracks added to the CD reissue of Armed Audio Warfare. It is an extended version of the B-side "Mars Needs Women" from the November 1988 God O.D. single. It has a funk-oriented sound, along with samples from the films The War of the Worlds and Mars Needs Women. The eleventh and final song, "Cutman", is a previously unreleased track, with five distinct parts, densely layered samples and soul, jazz and hip-hop influences.

Track listing

 * 1) "Genocide" – 5:17
 * 2) "Repulsion" – 3:23
 * 3) "Mister President" – 5:58
 * 4) "Reanimator" – 4:10
 * 5) "I Got the Fear" – 4:59
 * 6) "Kick That Man" – 5:25
 * 7) "Kneel and Buzz" – 4:33
 * 8) "Fear Version" – 1:07
 * 9) "Give Your Body Its Freedom" – 7:28

Additional tracks on the CD release:
 * 1) "Marrs Needs Women" – 4:11
 * 2) "Cutman" – 5:34

Personnel

 * Jack Dangers
 * Jonny Stephens
 * Greg Retch

title: Armed Audio Warfare


text:
Session (computer science)

In computer science and networking in particular, a session is a time-delimited two-way link, a practical (relatively high) layer in the TCP/IP protocol enabling interactive expression and information exchange between two or more communication devices or ends – be they computers, automated systems, or live active users (see login session). A session is established at a certain point in time, and then ‘torn down’ - brought to an end - at some later point. An established communication session may involve more than one message in each direction. A session is typically stateful, meaning that at least one of the communicating parties needs to hold current state information and save information about the session history to be able to communicate, as opposed to stateless communication, where the communication consists of independent requests with responses.

An established session is the basic requirement to perform a connection-oriented communication. A session also is the basic step to transmit in connectionless communication modes. However, any unidirectional transmission does not define a session.

Communication Transport may be implemented as part of protocols and services at the application layer, at the session layer or at the transport layer in the OSI model.
 * Application layer examples:
 * HTTP sessions, which allow associating information with individual visitors
 * A telnet remote login session
 * Session layer example:
 * A Session Initiation Protocol (SIP) based Internet phone call
 * Transport layer example:
 * A TCP session, which is synonymous to a TCP virtual circuit, a TCP connection, or an established TCP socket.

In the case of transport protocols that do not implement a formal session layer (e.g., UDP) or where sessions at the application layer are generally very short-lived (e.g., HTTP), sessions are maintained by a higher level program using a method defined in the data being exchanged. For example, an HTTP exchange between a browser and a remote host may include an HTTP cookie which identifies state, such as a unique session ID, information about the user's preferences or authorization level.

HTTP/1.0 was thought to only allow a single request and response during one Web/HTTP Session. Protocol version HTTP/1.1 improved this by completing the Common Gateway Interface (CGI), making it easier to maintain the Web Session and supporting HTTP cookies and file uploads.

Most client-server sessions are maintained by the transport layer - a single connection for a single session. However each transaction phase of a Web/HTTP session creates a separate connection. Maintaining session continuity between phases requires a session ID. The session ID is embedded within the <A HREF> or <FORM> links of dynamic web pages so that it is passed back to the CGI. CGI then uses the session ID to ensure session continuity between transaction phases. One advantage of one connection-per-phase is that it works well over low bandwidth (modem) connections.

Software implementation
TCP sessions are typically implemented in software using child processes and/or multithreading, where a new process or thread is created when the computer establishes or joins a session. HTTP sessions are typically not implemented using one thread per session, but by means of a database with information about the state of each session. The advantage with multiple processes or threads is relaxed complexity of the software, since each thread is an instance with its own history and encapsulated variables. The disadvantage is large overhead in terms of system resources, and that the session may be interrupted if the system is restarted.

When a client may connect to any server in a cluster of servers, a special problem is encountered in maintaining consistency when the servers must maintain session state. The client must either be directed to the same server for the duration of the session, or the servers must transmit server-side session information via a shared file system or database. Otherwise, the client may reconnect to a different server than the one it started the session with, which will cause problems when the new server does not have access to the stored state of the old one.

Server-side web sessions
Server-side sessions are handy and efficient, but can become difficult to handle in conjunction with load-balancing/high-availability systems and are not usable at all in some embedded systems with no storage. The load-balancing problem can be solved by using shared storage or by applying forced peering between each client and a single server in the cluster, although this can compromise system efficiency and load distribution.

A method of using server-side sessions in systems without mass-storage is to reserve a portion of RAM for storage of session data. This method is applicable for servers with a limited number of clients (e.g. router or access point with infrequent or disallowed access to more than one client at a time).

Client-side web sessions
Client-side sessions use cookies and cryptographic techniques to maintain state without storing as much data on the server. When presenting a dynamic web page, the server sends the current state data to the client (web browser) in the form of a cookie. The client saves the cookie in memory or on disk. With each successive request, the client sends the cookie back to the server, and the server uses the data to "remember" the state of the application for that specific client and generate an appropriate response.

This mechanism may work well in some contexts; however, data stored on the client is vulnerable to tampering by the user or by software that has access to the client computer. To use client-side sessions where confidentiality and integrity are required, the following must be guaranteed:
 * 1) Confidentiality: Nothing apart from the server should be able to interpret session data.
 * 2) Data integrity: Nothing apart from the server should manipulate session data (accidentally or maliciously).
 * 3) Authenticity: Nothing apart from the server should be able to initiate valid sessions.

To accomplish this, the server needs to encrypt the session data before sending it to the client, and modification of such information by any other party should be prevented via cryptographic means.

Transmitting state back and forth with every request is only practical when the size of the cookie is small. In essence, client-side sessions trade server disk space for the extra bandwidth that each web request will require. Moreover, web browsers limit the number and size of cookies that may be stored by a web site. To improve efficiency and allow for more session data, the server may compress the data before creating the cookie, decompressing it later when the cookie is returned by the client.

HTTP session token
A session token is a unique identifier that is generated and sent from a server to a client to identify the current interaction session. The client usually stores and sends the token as an HTTP cookie and/or sends it as a parameter in GET or POST queries. The reason to use session tokens is that the client only has to handle the identifier—all session data is stored on the server (usually in a database, to which the client does not have direct access) linked to that identifier. Examples of the names that some programming languages use when naming their HTTP cookie include JSESSIONID (JSP), PHPSESSID (PHP), CGISESSID (CGI), and ASPSESSIONID (ASP).

Session management
In human–computer interaction, session management is the process of keeping track of a user's activity across sessions of interaction with the computer system.

Typical session management tasks in a desktop environment include keeping track of which applications are open and which documents each application has opened, so that the same state can be restored when the user logs out and logs in later. For a website, session management might involve requiring the user to re-login if the session has expired (i.e., a certain time limit has passed without user activity). It is also used to store information on the server-side between HTTP requests.

Desktop session management
A desktop session manager is a program that can save and restore desktop sessions. A desktop session is all the windows currently running and their current content. Session management on Linux-based systems is provided by X session manager. On Microsoft Windows systems, session management is provided by the Session Manager Subsystem (smss.exe); user session functionality can be extended by third-party applications like twinsplay.

Browser session management
Session management is particularly useful in a web browser where a user can save all open pages and settings and restore them at a later date or on a different computer (see data portability).

To help recover from a system or application crash, pages and settings can also be restored on next run. Google Chrome, Mozilla Firefox, Internet Explorer, OmniWeb and Opera are examples of web browsers that support session management. Session management is often managed through the application of cookies.

Web server session management
Hypertext Transfer Protocol (HTTP) is stateless. Session management is the technique used by the web developer to make the stateless HTTP protocol support session state. For example, once a user has been authenticated to the web server, the user's next HTTP request (GET or POST) should not cause the web server to ask for the user's account and password again. For a discussion of the methods used to accomplish this see HTTP cookie and Session ID

In situations where multiple web servers must share knowledge of session state (as is typical in a cluster environment) session information must be shared between the cluster nodes that are running web server software. Methods for sharing session state between nodes in a cluster include: multicasting session information to member nodes (see JGroups for one example of this technique), sharing session information with a partner node using distributed shared memory or memory virtualization, sharing session information between nodes using network sockets, storing session information on a shared file system such as a distributed file system or a global file system, or storing the session information outside the cluster in a database. If session information is considered transient, volatile data that is not required for non-repudiation of transactions and does not contain data that is subject to compliance auditing (in the U.S. for example, see the Health Insurance Portability and Accountability Act and the Sarbanes–Oxley Act for examples of two laws that necessitate compliance auditing) then any method of storing session information can be used. However, if session information is subject to audit compliance, consideration should be given to the method used for session storage, replication, and clustering.

In a service-oriented architecture, Simple Object Access Protocol or SOAP messages constructed with Extensible Markup Language (XML) messages can be used by consumer applications to cause web servers to create sessions.

Session management over SMS
Just as HTTP is a stateless protocol, so is SMS. As SMS became interoperable across rival networks in 1999, and text messaging started its ascent towards becoming a ubiquitous global form of communication, various enterprises became interested in using the SMS channel for commercial purposes. Initial services did not require session management since they were only one-way communications (for example, in 2000, the first mobile news service was delivered via SMS in Finland). Today, these applications are referred to as application-to-peer (A2P) messaging as distinct from peer-to-peer (P2P) messaging. The development of interactive enterprise applications required session management, but because SMS is a stateless protocol as defined by the GSM standards, early implementations were controlled client-side by having the end-users enter commands and service identifiers manually.

title: Session (computer science)


text: Category:Energy

title: Category:Energy


text:
Kun'yomi

Kun'yomi (訓読み), is a reading based on the pronunciation of a native Japanese word, or yamato kotoba, that closely approximated the meaning of the corresponding Chinese character when it was introduced.

Characteristics
Kun'yomi are characterized by the strict (C)V syllable structure of yamato kotoba. Most noun or adjective kun'yomi are two to three syllables long, while verb kun'yomi are usually between one and three syllables in length, not counting trailing hiragana called okurigana. Okurigana are not considered to be part of the internal reading of the character, although they are part of the reading of the word. A beginner in the language will rarely come across characters with long readings, but readings of three or even four syllables are not uncommon. This contrasts with on'yomi, which are monosyllabic, and is unusual in the Chinese family of scripts, which generally use one character per syllable—not only in Chinese, but also in Korean, Vietnamese, and Zhuang; polysyllabic Chinese characters are rare and considered non-standard.

As with on'yomi, there can be multiple kun'yomi for the same kanji, and some kanji have no kun'yomi at all. For instance, the character for east, 東, has tō as its on'yomi, from Middle Chinese . However, Japanese already had two words for "east": higashi and azuma. Thus the kanji 東 had the latter readings added as kun'yomi. In contrast, the kanji 寸, denoting a Chinese unit of measurement (about 30 mm or 1.2 inch), has no native Japanese equivalent; it only has an on'yomi, sun, with no native kun'yomi.

Usage
In a number of cases, multiple kanji were assigned to cover a single Japanese word. Typically when this occurs, the different kanji refer to specific shades of meaning. For instance, the word なおす, naosu, when written 治す, means "to heal an illness or sickness". When written 直す it means "to fix or correct something". Sometimes the distinction is very clear, although not always. Differences of opinion among reference works are not uncommon; one dictionary may say the kanji are equivalent, while another dictionary may draw distinctions of use. As a result, native speakers of the language may have trouble knowing which kanji to use and resort to personal preference or by writing the word in hiragana. This latter strategy is frequently employed with more complex cases such as もと moto, which has at least five different kanji: 元, 基, 本, 下, and 素, the first three of which have only very subtle differences. Another notable example is sakazuki "sake cup", which may be spelt as at least five different kanji: 杯, 盃, 巵/卮, and 坏; of these, the first two are common—formally 杯 is a small cup and 盃 a large cup.

Local dialectical readings of kanji are also classified under kun'yomi, most notably readings for words in Ryukyuan languages. Further, in rare cases gairaigo (borrowed words) have a single character associated with them, in which case this reading is formally classified as a kun'yomi, because the character is being used for meaning, not sound.

Most kokuji, Japanese-created Chinese characters, only have kun'yomi, although some have back-formed a pseudo-on'yomi by analogy with similar characters, such as 働 dō, from 動 dō, and there are even some, such as 腺 sen "gland", that have only an on'yomi.

Examples
承る uketamawaru, 志 kokorozashi, and 詔 mikotonori have five syllables represented by a single kanji, the longest readings in the jōyō character set. These unusually long readings are due to a single character representing a compound word:

Further, some Jōyō characters have long non-Jōyō readings (students learn the character, but not the reading), such as omonpakaru for 慮る.
 * 承る is a single character for a compound verb, one component of which has a long reading.
 * It has an alternative spelling as 受け賜る u(ke)-tamawa(ru), hence (1+1)+3=5.
 * Compare common 受け付ける u(ke)-tsu(keru).
 * 志 is a nominalization of the verb 志す which has a long reading kokoroza(su).
 * This is due to its being derived from a noun-verb compound, 心指す kokoro-za(su).
 * The nominalization removes the okurigana, hence increasing the reading by one mora, yielding 4+1=5.
 * Compare common 話 hanashi 2+1=3, from 話す hana(su).
 * 詔 is a triple compound.
 * It has an alternative spelling 御言宣 mi-koto-nori, hence 1+2+2=5.

title: Kun'yomi


text:
99%

99% may refer to:

Music

 * 99 Percent, an American hip hop duo
 * 99% (Meat Beat Manifesto album), 1990
 * 99% (Ska-P album), 2013
 * "99 Percenters", a 2011 song by Ministry
 * "99%", a song by Soul Asylum from the 1992 album Grave Dancers Union

Other uses

 * 99 Percent – Civic Voice, a political party in Slovakia
 * 99%: The Occupy Wall Street Collaborative Film, a 2013 documentary film
 * We are the 99%, a political slogan

title: 99%


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Batesian mimicry

Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both. It is named after the English naturalist Henry Walter Bates, who worked on butterflies in the rainforests of Brazil.

Batesian mimicry is the most commonly known and widely studied of mimicry complexes, such that the word mimicry is often treated as synonymous with Batesian mimicry. There are many other forms however, some very similar in principle, others far separated. It is often contrasted with Müllerian mimicry, a form of mutually beneficial convergence between two or more harmful species. However, because the mimic may have a degree of protection itself, the distinction is not absolute. It can also be contrasted with functionally different forms of mimicry. Perhaps the sharpest contrast here is with aggressive mimicry where a predator or parasite mimics a harmless species, avoiding detection and improving its foraging success.

The imitating species is called the mimic, while the imitated species (protected by its toxicity, foul taste or other defenses) is known as the model. The predatory species mediating indirect interactions between the mimic and the model is variously known as the [signal] receiver, dupe or operator. By parasitising the honest warning signal of the model, the Batesian mimic gains an advantage, without having to go to the expense of arming itself. The model, on the other hand, is disadvantaged, along with the dupe. If impostors appear in high numbers, positive experiences with the mimic may result in the model being treated as harmless. At higher frequency there is also a stronger selective advantage for the predator to distinguish mimic from model. For this reason, mimics are usually less numerous than models, an instance of frequency-dependent selection. Some mimetic populations have evolved multiple forms (polymorphism), enabling them to mimic several different models and thereby to gain greater protection. Batesian mimicry is not always perfect. A variety of explanations have been proposed for this, including limitations in predators' cognition.

While visual signals have attracted most study, Batesian mimicry can employ deception of any of the senses; some moths mimic the ultrasound warning signals sent by unpalatable moths to bat predators, constituting auditory Batesian mimicry, while some weakly electric fish appear to mimic the electrolocation signals of strongly electric fish, probably constituting electrical mimicry.

Historical background

Henry Walter Bates (1825–1892) was an English explorer-naturalist who surveyed the Amazon rainforest with Alfred Russel Wallace in 1848. While Wallace returned in 1852, Bates remained for over a decade. Bates's field research included collecting almost a hundred species of butterflies from the families Ithomiinae and Heliconiinae, as well as thousands of other insects specimens. In sorting these butterflies into similar groups based on appearance, inconsistencies began to arise. Some appeared superficially similar to others, so much so that even Bates could not tell some species apart based only on wing appearance. However, closer examination of less obvious morphological characters seemed to show that they were not even closely related. Shortly after his return to England, he read a paper on his theory of mimicry at a meeting of the Linnean Society of London on 21 November 1861, which was then published in 1862 as 'Contributions to an Insect Fauna of the Amazon Valley' in the society's Transactions. He elaborated on his experiences further in The Naturalist on the River Amazons.

Bates put forward the hypothesis that the close resemblance between unrelated species was an antipredator adaptation. He noted that some species showed very striking coloration and flew in a leisurely manner, almost as if taunting predators to eat them. He reasoned that these butterflies were unpalatable to birds and other insectivores, and were thus avoided by them. He extended that logic to forms that closely resembled such protected species and mimicked their warning coloration but not their toxicity.

This naturalistic explanation fitted well with the recent account of evolution by Wallace and Charles Darwin, as outlined in his famous 1859 book The Origin of Species. Because the Darwinian explanation required no supernatural forces, it met with considerable criticism from anti-evolutionists, both in academic circles and in the broader social realm.

Aposematism

Most living things have predators and therefore are in a constant evolutionary arms race to develop antipredator adaptations, while the predator adapts to become more efficient at defeating the prey's adaptations. Some organisms have evolved to make detection less likely, for example by nocturnality and camouflage. Others have developed chemical defences such as the deadly toxins of certain snakes and wasps, or the noxious scent of the skunk. Such prey often send clear and honest warning signals to their attackers with conspicuous aposematic (warning) patterns. The brightness of such warning signs is correlated with the level of toxicity of the organism.

In Batesian mimicry, the mimic effectively copies the coloration of an aposematic animal, known as the model, to deceive predators into behaving as if it were distasteful. The success of this dishonest display depends on the level of toxicity of the model and the abundance of the model in the geographical area. The more toxic the model is, the more likely it is that the predator will avoid the mimic. The abundance of the model species is also important for the success of the mimic because of frequency-dependent selection. When the model is abundant, mimics with imperfect model patterns or slightly different coloration from the model are still avoided by predators. This is because the predator has a strong incentive to avoid potentially lethal organisms, given the likelihood of encountering one. However, in areas where the model is scarce or locally extinct, mimics are driven to accurate aposematic coloration. This is because predators attack imperfect mimics more readily where there is little chance that they are the model species. Frequency-dependent selection may also have driven Batesian mimics to become polymorphic in rare cases where a single genetic switch controls appearance, as in the swallowtail butterflies (the Papilionidae) such as the pipevine swallowtail, and in the New Zealand stonefly Zelandoperla fenestrata.

Classification and comparisons
Batesian mimicry is a case of protective or defensive mimicry, where the mimic does best by avoiding confrontations with the signal receiver. It is a disjunct system, which means that all three parties are from different species. An example would be the robber fly Mallophora bomboides, which is a Batesian mimic of its bumblebee model and prey, B. americanorum (now more commonly known as Bombus pensylvanicus), which is noxious to predators due to its sting.

Batesian mimicry stands in contrast to other forms such as aggressive mimicry, where the mimic profits from interactions with the signal receiver. One such case of this is in fireflies, where females of one species mimic the mating signals of another species, deceiving males to come close enough for them to eat. Mimicry sometimes does not involve a predator at all though. Such is the case in dispersal mimicry, where the mimic once again benefits from the encounter. For instance, some fungi have their spores dispersed by insects by smelling like carrion. In protective mimicry, the meeting between mimic and dupe is not such a fortuitous occasion for the mimic, and the signals it mimics tend to lower the probability of such an encounter.

A case somewhat similar to Batesian mimicry is that of mimetic weeds, which imitate agricultural crops. In weed or Vavilovian mimicry, the weed survives by having seeds which winnowing machinery identifies as belonging to the crop. Vavilovian mimicry is not Batesian, because man and crop are not enemies. By contrast, a leaf-mimicking plant, the chameleon vine, employs Batesian mimicry by adapting its leaf shape and colour to match that of its host to deter herbivores from eating its edible leaves.

Another analogous case within a single species has been termed Browerian mimicry (after Lincoln P. Brower and Jane Van Zandt Brower ). This is a case of automimicry; the model is the same species as its mimic. Equivalent to Batesian mimicry within a single species, it occurs when there is a palatability spectrum within a population of harmful prey. For example, monarch (Danaus plexippus) caterpillars feed on milkweed species of varying toxicity. Some feed on more toxic plants and store these toxins within themselves. The more palatable caterpillars thus profit from the more toxic members of the same species.

Another important form of protective mimicry is Müllerian mimicry, discovered by and named after the naturalist Fritz Müller. In Müllerian mimicry, both model and mimic are aposematic, so mimicry may be mutual, does not necessarily constitute a bluff or deception and as in the wasps and bees may involve many species in a mimicry ring.

Imperfect Batesian mimicry

In imperfect Batesian mimicry, the mimics do not exactly resemble their models. An example of this is the fly Spilomyia longicornis, which mimics vespid wasps. However, it is not a perfect mimic. Wasps have long black antennae and this fly does not. Instead, they wave their front legs above their heads to look like the antennae on the wasps. Many reasons have been suggested for imperfect mimicry. Imperfect mimics may simply be evolving towards perfection. They may gain advantage from resembling multiple models at once. Humans may evaluate mimics differently from actual predators. Mimics may confuse predators by resembling both model and nonmimic at the same time (satyric mimicry). Kin selection may enforce poor mimicry. The selective advantage of better mimicry may not outweigh the advantages of other strategies like thermoregulation or camouflage. Only certain traits may be required to deceive predators; for example, tests on the sympatry/allopatry border (where the two are in the same area, and where they are not) of the mimic Lampropeltis elapsoides and the model Micrurus fulvius showed that color proportions in these snakes were important in deceiving predators but that the order of the colored rings was not.

Plants mimicking ants

Batesian mimicry of ants appears to have evolved in certain plants, as a visual anti-herbivory strategy, analogous to a herbivorous insect's mimicking a well-defended insect to deter predators. Passiflora flowers of at least 22 species, such as P. incarnata, have dark dots and stripes on their flowers thought to serve this purpose.

Acoustic mimicry

Predators may identify their prey by sound as well as sight; mimics have accordingly evolved to deceive the hearing of their predators. Bats are nocturnal predators that rely on echolocation to detect their prey. Some potential prey are unpalatable to bats, and produce an ultrasonic aposematic signal, the auditory equivalent of warning coloration. In response to echolocating red bats and big brown bats, tiger moths such as Cycnia tenera produce warning sounds. Bats learn to avoid the harmful moths, but similarly avoid other species such as some pyralid moths that produce such warning sounds as well. Acoustic mimicry complexes, both Batesian and Müllerian, may be widespread in the auditory world.

Electrical mimicry
The electric eel, Electrophorus, is capable of delivering a powerful electric shock that can stun or kill its prey. Bluntnose knifefishes, Brachyhypopomus, create an electric discharge pattern similar to the low voltage electrolocation discharge of the electric eel. This is thought to be Batesian mimicry of the powerfully protected electric eel.

title: Batesian mimicry


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Wikipedia talk:Requested articles/Other

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title: Wikipedia talk:Requested articles/Other