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Thank you for your care in using an edit summary when contributing. Thanks for the new section in binomial theorem. Cheers, Oleg Alexandrov (talk) 01:29, 16 December 2005 (UTC)[reply]

First of all, please sign your posts with ~~~~. About the article, since it's merely a section of a movie, its proper place, if it belongs anywhere, is on the page of that movie, Kentucky Fried Movie. --InShaneee 06:02, 17 December 2005 (UTC)[reply]

• Let's keep this civil, I have nothing against you personally. Also, you CAN redirect to a specific point on a page. Here's the format: [[Blah#Specific Blah]], where Blah is the article name, and Specific Blah is the specific section header. That help any? --InShaneee 06:38, 17 December 2005 (UTC)[reply]
  • Bizzare...that page must be outdated, because I use that type of redirect all the time. I'll have to look into getting that info changed. In the meantime, go ahead and merge the info and try out the redirect to the anchor for yourself! --InShaneee 07:08, 17 December 2005 (UTC)[reply]
    • The 'allies' section of Teen Titans (animated series) is where I first encountered them. It appears to work for a section titled like this: ===Blah===, so try using three "="'s when you create your new subsection, that should work. --InShaneee 07:36, 17 December 2005 (UTC)[reply]
      • No, unfortunatly, it appears you were right. I was thinking of the wrong thing, my bad. Still, the merge/redirect seems to solve the problem. Since "Zinc Oxide and You" is the name of a segment within Kentucky Fried Movie, I see two possibilities. One, someone is looking for more info about KFM, which this takes them to. Two, people are looking for that specific segment in that movie, which is not only on that page, but the information about the rest of the movie may be of interest to the user as well. This is typically the policy, anyway, as once someone started creating articles about individual chapters of "Great Expectations", and the verdict on that was to merge them into the article about the book as a whole. --InShaneee 05:20, 18 December 2005 (UTC)[reply]

The reason I removed the TOCRight was that a while back it was up for deletion under the rationale that, if TOCRight is going to be used to remove whitespace in an article, then what's stopping us from using it in every article, or just making it the default altogether? In the end, the consensus was that it was only really appropriate for pages like this. And as for most users not scrolling down and only seeing the top of the page, well, that's why articles need good introductory paragraphs :) QVanillaQ 15:21, 21 February 2006 (UTC)[reply]

• Found the old discussion: Wikipedia:Templates_for_deletion/TOCright QVanillaQ 15:37, 21 February 2006 (UTC)[reply]

Excellent editing! Rklawton 19:51, 5 June 2006 (UTC)[reply]

Spacecraft propulsion is up for a featured article review, and I noticed your name often in the edit history. Detailed concerns about the article may be found here. Please leave your comments if you're able to help us maintain this article's featured quality. Sandy 03:41, 3 October 2006 (UTC)[reply]

That last edit of yours after mine works. My reason for adding-in the Art Center bit in the first place was personal. I added Scripps afterward just to make Tech look better. I later regretted starting this war. Thanks for ending it.

By the way, I tried InShanee's way of linking to a header on a page, and it works, but it's ugly. Any way to hide the "#"? Grammarmonger_TALK 17:36, 3 January 2007 (UTC)[reply]

No, Lou, I was referring to the "#" symbol, which directs the browser to the specific article header. Grammarmonger 18:26, 3 January 2007 (UTC)[reply]

I thought I did this. Look at the heading above - it says Academics at Caltech, but goes to the right spot in the article. I thought this is what you wanted - the # is no longer visible to the reader, though it is to the editor. LouScheffer 18:32, 3 January 2007 (UTC)[reply]

Yeah, that's the ticket. I see it now. Thanks! Grammarmonger 18:55, 3 January 2007 (UTC)[reply]

I don't think that the image is creative commons. The website requires explicit written permission to be reused. Do you have a copy of that to link to from the image page? mikm 14:37, 28 March 2007 (UTC)[reply]

Yes, Prof. Davidson gave explicit written permission. Here is the email trail I have for this:

From: Louis Scheffer <lou@cadence.com> To: Michael W. Davidson <davidson@magnet.fsu.edu> Date: Jan 4 2006 - 10:40am

Thanks! I've included it on the page,

Lou Scheffer

Original Message-----

From: Michael W. Davidson [1] Sent: Wed 1/4/2006 8:48 AM To: Louis Scheffer Subject: RE: Can I use a picture of your on Wikipedia?

Lou,

That will be fine.

Mike

Michael W. Davidson National High Magnetic Field Laboratory 1800 East Paul Dirac Drive The Florida State University Tallahassee, Florida 32310 Email: davidson@magnet.fsu.edu Phone: 850-644-0542 Web: Molecular Expressions (http://microscopy.fsu.edu)

Original Message-----

From: Louis Scheffer [2] Sent: Tuesday, January 03, 2006 6:58 PM To: davidson@magnet.fsu.edu Subject: Can I use a picture of your on Wikipedia?

Hi, Prof. Davidson!

I made a Wikipedia page for silicon art. It refers, of course, to your web site for examples.

http://en.wikipedia.org/wiki/Chip_art

I'd like to have an example for the page, and was wondering if I could I use one of your pictures? I was thinking of the picture on

http://micro.magnet.fsu.edu/creatures/pages/buffalochips.html

because, as an original author, I can get the permissions for the design itself, so all I'd need is permission to use your picture of it.

Can I get this permission? I'd be more than happy to credit you, and your web site, which I think is great.

Thanks, Lou Scheffer

LouScheffer 15:48, 28 March 2007 (UTC)[reply]

Hello, this is a message from an automated bot. A tag has been placed on ECAD, Inc., by Witchinghour, another Wikipedia user, requesting that it be speedily deleted from Wikipedia. The tag claims that it should be speedily deleted because ECAD, Inc. seems to be about a person, group of people, band, club, company, or web content, but it does not indicate how or why the subject is notable: that is, why an article about that subject should be included in an encyclopedia. Under the criteria for speedy deletion, articles that do not assert the subject's importance or significance may be deleted at any time. Please see the guidelines for what is generally accepted as notable.

To contest the tagging and request that administrators wait before possibly deleting ECAD, Inc., please affix the template {{hangon}} to the page, and put a note on its talk page. If the article has already been deleted, see the advice and instructions at WP:WMD. Please note, this bot is only informing you of the nomination for speedy deletion, it did not nominate ECAD, Inc. itself. Feel free to leave a message on the bot operator's talk page if you have any questions about this or any problems with this bot. --Android Mouse Bot 2 11:46, 9 June 2007 (UTC)[reply]

Good work, maybe I should tag few more articles for deletion to get people working. nice job --Witchinghour 17:48, 10 June 2007 (UTC)[reply]

By the way that was meant as a joke but somebody missed it :( --Witchinghour 20:07, 10 June 2007 (UTC)[reply]

Hi Lou. I have a small note. Per WP:MoS#Sections and headings, one should use lowercase in section headings, so one should write

==The binomial theorem in popular culture==

instead of

==The Binomial Theorem in Popular Culture==

Small thing, but I thought I'd let you know. Cheers, Oleg Alexandrov (talk) 03:30, 11 June 2007 (UTC)[reply]

Thanks for uploading Image:ChipWorksLandShark.jpg. Wikipedia gets thousands of images uploaded every day, and in order to verify that the images can be legally used on Wikipedia, the source and copyright status must be indicated. Images need to have an image tag applied to the image description page indicating the copyright status of the image. This uniform and easy-to-understand method of indicating the license status allows potential re-users of the images to know what they are allowed to do with the images.

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This is an automated notice by OrphanBot. If you need help on selecting a tag to use, or in adding the tag to the image description, feel free to post a message at Wikipedia:Media copyright questions. 21:06, 19 June 2007 (UTC)

Your addition Intelligent life need not be technological is also touched on in the section They are too alien. Perhaps you might look at merging these? - Vedexent (talk) - 05:27, 21 June 2007 (UTC)[reply]

A reasonable question. I've moved it to Talk:Fermi paradox. LouScheffer 06:03, 21 June 2007 (UTC)[reply]

Well, I guess I'm being "re-bold." One thing I will say: if a section goes in unsourced, it should be removed. It's the bane of this page. Anyhow, we can save it for article talk. Marskell 16:59, 21 June 2007 (UTC)[reply]

HI the main Hubble Space article is superb but the Telescope artice is quite poor indeed, Is there any way you could help write it professionally with references into a GA encyclopedia article. I came acrosss it just now expecting to see another great article and was quite disappointed with it compared to other work on astronomy on wikpiedia. It didn;t even had a history -I've added it - it just needs condensing and structuring and a great deal of work. Thanks ♦ Sir Blofeld ♦ ^{"Expecting you?" Contribs} 16:59, 18 August 2007 (UTC)[reply]

Hello, this is a message from an automated bot. A tag has been placed on Council on EDA, by another Wikipedia user, requesting that it be speedily deleted from Wikipedia. The tag claims that it should be speedily deleted because Council on EDA is a redirect to a non-existent page (CSD R1).

To contest the tagging and request that administrators wait before possibly deleting Council on EDA, please affix the template {{hangon}} to the page, and put a note on its talk page. If the article has already been deleted, see the advice and instructions at WP:WMD. Feel free to contact the bot operator if you have any questions about this or any problems with this bot, bearing in mind that this bot is only informing you of the nomination for speedy deletion; it does not perform any nominations or deletions itself. CSDWarnBot 02:32, 26 August 2007 (UTC)[reply]

Yeah, some collateral damage was had there whilst cleaning up the nightmares of stupid edits. Something for me to clean up tomorrow when i've got a fair few more neurons firing. Thewinchester ^(talk) 16:06, 2 October 2007 (UTC)[reply]

beautiful job on fictional use of real materials. I suggest what is needed now is a few real sources from secondary works, to show it can be done. At the AfD I suggested dilithium, but most of these should be discussed in reviews, etc. then, perhaps for the biggies, like gold, and water, there should be a breakout to a separate article. As you know, what happens at AfD is unpredictable--please make sure you have a copy off-wiki to use in reconstructing it in other ways, which can be considered if necessary. I'd help more, but this is a busy day at WP. See [3]. DGG (talk) 22:19, 9 October 2007 (UTC)[reply]

I'm sure no slight or malfeasance was intended, but please do not move my talk page comments into a different section that pertains to the same incident. I was neither replying to your comments already there nor discussing the same subject matter; placing them into the same section makes it difficult to have a threaded conversation on two different subjects. Thanks! /Blaxthos 14:22, 12 October 2007 (UTC)[reply]

• Hi! I was busily cleaning up Fictional applications of real materials to address most of the objections when it was deleted. Since the AfD started, I added scope limitations at the top, removed a bunch of stuff that was just trivia, and was busy adding secondary and tertiary sources (For almost every remaining entry I was able to find a secondary source, and I have added about 5 so far). (You can compare the article from before the AfD to the current one to get a sense of these changes). You yourself say:

As a result, I vote, and recommend, the use of "Delete unless cleaned up", "Delete unless expanded", etc. — if somebody cares enough about the article to have it kept, then they will generally fix it up during the AFD vote, which is five days long, and drop me a line on my talk page to ask me to have another look.

This is exactly what I was busy doing. I'd be grateful if you could take another look. LouScheffer 22:19, 11 October 2007 (UTC)[reply]

Thanks for your message. I'm happy with the way I've closed this one but you're welcome to ask for a deletion review. Stifle (talk) 17:16, 12 October 2007 (UTC)[reply]

WP:DRV

Thanks for the notice. /Blaxthos 21:26, 12 October 2007 (UTC)[reply]

EDASeeAlso template

While pointing out specific fee-based access to IEEE and ACM publications "servers a useful service", such service is not the purpose of Wikipedia. The template is a cookie-cutter that was very inacurrate about ATPG. It would have been more useful to pointout the International Test Conference. I suggest that you remove these templates as they break the style of "See Also", are not subject specific, and are a form of advertising. TeamX 03:13, 20 October 2007 (UTC)[reply]

Community member - I am attaching the following SPAM template. There are three key issues with your template:
1) It refers readers to external links where a fee is required.
2) It is not consistent with the "See Also" sections of the articles.
3) The wording of the template does not fit all articles.

Please discontinue use of this template and instead consider putting specific links to specific, relevant articles. Thank you. TeamX 00:16, 21 October 2007 (UTC)[reply]

Welcome to Wikipedia. Everyone is welcome to contribute constructively to the encyclopedia. However, one or more of the external links you added do not comply with our guidelines for external links and have been removed. Wikipedia is not a collection of links; nor should it be used for advertising or promotion. Since Wikipedia uses nofollow tags, external links do not alter search engine rankings. If you feel the link should be added to the article, then please discuss it on the article's talk page before reinserting it. Please take a look at the welcome page to learn more about contributing to this encyclopedia. Thank you.

Your statement about adding the "template text" suggests that the template is not standard - and indeed it cannot be if it must be modified for each topic. PLEASE remove it. Also, you are breaking the "See Also" section style. TeamX 07:15, 27 October 2007 (UTC)[reply]

The new wording is marginally better-- at least you didn't turn a sentence written in active voice into one written in passive voice-- but still reads awkwardly.

And, yes, I do find it a little disconcerting to find an article with a paragraph discussing my work, carefully written and rewritten in such a way to avoid mentioning my name. Geoffrey.landis 06:23, 10 November 2007 (UTC)[reply]

FYI, the reason the page uses aluminium is not b/c that's what the discoverer named it, but rather because that's what IUPAC decided as its official name. [Sulfur is the official name of that element; sulphur is an accepted, but incorrect, spelling.] Samer (talk) 15:30, 17 November 2007 (UTC)[reply]

Hi Lou, I'm currently reading the semiconductor device modeling article. the article talks about a figure 1b which I cannot spot in the article. Can it be that the article is currently missing this figure? Thank you! --Abdull (talk) 11:23, 18 November 2007 (UTC)[reply]

Hi, thank you for adding the image so fast. To appreciate your work, I bestow you a little Kinkajou: . Don't feel worried. Their conservation status is of least concern. Bye, --Abdull (talk) 20:30, 19 November 2007 (UTC)[reply]

Thanks for uploading Image:TCAD-circuit.jpg. Wikipedia gets thousands of images uploaded every day, and in order to verify that the images can be legally used on Wikipedia, the source and copyright status must be indicated. Images need to have an image tag applied to the image description page indicating the copyright status of the image. This uniform and easy-to-understand method of indicating the license status allows potential re-users of the images to know what they are allowed to do with the images.

For more information on using images, see the following pages:

• Wikipedia:Image use policy
• Wikipedia:Image copyright tags

This is an automated notice by OrphanBot. If you need help on selecting a tag to use, or in adding the tag to the image description, feel free to post a message at Wikipedia:Media copyright questions. --OrphanBot (talk) 02:08, 19 November 2007 (UTC)[reply]

Hi! I want to thank you for the addition you made recently to the Near-Earth asteroid article. Your explanation of why the probability goes up and then down again, with the accompanying graphic, is really clear and easy to understand. Is there by any chance a source we could cite for this information? (I'm not myself challenging it as WP:OR, but I would hate to lose that content because someone else thought it violated that policy!) (sdsds - talk) 02:13, 15 January 2008 (UTC)[reply]

Thanks for catching that. I dont know how I ended up misspelling that, lol. Must of been doing two things at once or something, and got mixed up on something. Thanks again :) Whammies Were Here 11:40, 24 January 2008 (UTC)[reply]

Thanks for coming and checking the article out. Thanks for putting TNT equivalents for Type II, and Type III, it did add quite a bit of perspective for the laymen audience. I will be doing my best to refrain adding to the Kardashev scale, until the current dispute can be talked about more. I've responded to your discussion on the Talk:kardashev scale. Thanks again for coming by and be involved.--Sparkygravity (talk) 14:21, 31 January 2008 (UTC)[reply]

Hubble Space Telescope has been nominated for a featured article review. Articles are typically reviewed for two weeks. Please leave your comments and help us to return the article to featured quality. If concerns are not addressed during the review period, articles are moved onto the Featured Article Removal Candidates list for a further period, where editors may declare "Keep" or "Remove" the article from featured status. The instructions for the review process are here. Reviewers' concerns are here. --Kaypoh (talk) 05:05, 21 March 2008 (UTC)[reply]

I was so pleased to see that HST was kept at FA. It's always a bit daunting to copyedit a technical article - especially such a long one - and with the added pressure of this one being up for FAR, I was particularly concerned about getting it right. Thanks for all your hard work on it, and for being so receptive of my edits during the FAR. It was a pleasure to work with you. Maralia (talk) 05:37, 30 April 2008 (UTC)[reply]

Thanks for your work. It's always helpful to have another set of eyes look over an article, even when (and maybe especially when) they are not super familiar with the area. You noticed (and fixed) a whole bunch of issues I must have seen a hundred times, but did not even notice they could be improved until you fixed them. It was a pleasure working with you as well, LouScheffer (talk) 06:32, 30 April 2008 (UTC)[reply]

• And my thanks, especially to you, Lou, for your continuing attention to this article. Sardanaphalus (talk) 08:18, 30 April 2008 (UTC)[reply]

Just a quick note - I took the liberty of moving your response to my posting about privacy concerns with the DOI bot. In trying to respond to it I couldn't figure how to do it so that my response would be clear to readers who didn't see the history. So I moved your response to after the initial post, and then indented my response below it. I hope that is okay. Thank you. Zodon (talk) 01:39, 3 May 2008 (UTC)[reply]

Hi, thanks for your "test" - it was good fun, and turned up one CrossRef bug I would never have spotted!

So... Did I pass?

Smith609 Talk 00:05, 10 May 2008 (UTC)[reply]

Looks good. I tried it myself but still got the old results (I guess you are running new code). As you find new examples that have problems, you can add them to the page, so you can verify new changes don't break the old fixes.... LouScheffer (talk) 04:43, 10 May 2008 (UTC)[reply]

Hi. I've just suggested the QUIET telescope article for a Did you know? entry on the Main Page; the nomination is at Template talk:Did you know#Articles created.2Fexpanded on May 23. Hopefully it will receive a surge of traffic from that in a few days. Thanks for starting the article. Mike Peel (talk) 18:03, 24 May 2008 (UTC)[reply]

Hi! I was quite surprised when you started to add to the article so quickly after it was created. Many times technical articles on rather specialized topics just sit there, but you expanded it from a near-stub to a real article almost instantly. (This was my eventual intention as well, but it would have taken a lot longer.) I really appreciate Wikipedia as a great resource for technical topics, and it's always great to see new stuff appear. And thanks as well for the pointer to the 'did you know' section - I had no idea of how snippets got there. Thanks again, LouScheffer (talk) 19:53, 24 May 2008 (UTC)[reply]

I noticed your additions of links to the article on Template:CMB experiments and Cosmic Background Imager, and thought that it would be a nice article to expand and get on DYK. It helps that I work in the field (but not on this experiment). At some point I plan on doing the same to the rest of the CMB articles, but I have a finite amount of time. :( I figure that they'd make a nice featured topic eventually. Mike Peel (talk) 20:26, 24 May 2008 (UTC)[reply]

Hi and thank you for your edit at Hubble Space Telescope. I didn't believe you so I decided to check for myself and contacted Lars Lindberg Christensen from the European Space Agency (ESO) regarding origins of the video file Image:Hst15 black hole2 1.ogg. I must concede with your arguments. Because of you, in turn, I have made a change to the file reference. The "reference" section is now called "annotated reference" and describes the issue you raised within the edit summary of your afformentioned edit. Thank you. --CyclePat (talk) 18:45, 24 May 2008 (UTC)[reply]

On 28 May, 2008, Did you know? was updated with a fact from the article QUIET, which you created or substantially expanded. If you know of another interesting fact from a recently created article, then please suggest it on the Did you know? talk page.

--BorgQueen (talk) 16:47, 28 May 2008 (UTC)[reply]

for the record, though the port chicago disaster involved a larger quantity of explosives, the blast-force recorded was actually less than that of the halifax explosion. amplification occurred due to the elevation of the blast in relation to the harbour bottom. it was a unique scientific discovery at the time, which eventually led to the decision to detonate the first atomic weapons at a specific altitude (rather than on the land surface), because they knew it would increase the weapon's power to devastate. this information comes from a documentary which periodically airs on the discovery channel. 142.68.133.42 (talk) 18:54, 4 June 2008 (UTC)[reply]

To: Lou Scheffer, GPS Editor

I am somewhat confused by the sentence,

"Dividing the speed of light by the distance adjustment required to make the pseudoranges come as close as possible to intersecting results in a guess of the difference between UTC and the time indicated by the receiver's on-board clock."

in the subheading "Using the C/A code" of the "Calculating positions" heading in the article, GPS.

The confusion arises because the result of the division gives a quotient which is in inverse time whereas the later part of the sentence indicates that the dimensions of this quotient should be time rather than inverse time. Should this quotient be (distance adjustment)/(speed of light) instead? You may reply to my talk page if you wish. RHB100 (talk) 19:42, 27 June 2008 (UTC)[reply]

I did not write this section, but reading it, I agree completely. A distance divided by a speed gives a time, which is exactly what is mentioned in the second half. So your proposed change makes both physical and mathematical sense. LouScheffer (talk) 20:10, 27 June 2008 (UTC)[reply]

I think the equation you added is good and I hope it will be judged readable by a general audience. I made a small change to the notation used for actual received time in order to avoid conflict with the r4 notation used below.

The material in the paragraph beginning with "The following description shows a straightforward iterative way." is good.

Although there are well known techniques for finding the root of a single non-linear equation, the problem is far more difficult for the case of multidimensional non-linear equations. In "Numerical Recipes" it is stated, "Why is that task (relatively) easy, while multidimensional root finding is often quite hard?" So with regard to your first bullet under the equation, I do not think the equations can be solved so simply.

In your second bullet, you mention the intersection of hyperbolas. But do we know of any reference to a GPS receiver vendor who uses the intersection of hyperbolas or hyperboloids. The Garmin User's Guide talks about the intersection of spheres but not hyperboloids. The Wikipedia article, Multilateration, does not mention GPS as an application.

The third bullet describes a technique which may work but the reference is not accessible to the general reader. The description of the overall approach is not enough for the general reader to understand how this algorithm works.RHB100 (talk) 23:44, 12 July 2008 (UTC)[reply]

Sorry, I thought that was a random comment on that article. I was in a sort of hurry, and I noticed that in the last minute. ~ Troy (talk) 23:23, 11 July 2008 (UTC)[reply]

Thw equation, , defines as the value computed based on no clock error since the received time is tr_i and the sent time is t_i. Since tr_i is defined as the received time it has no error. Since t_i is defined as the sent time it has no error. To include the clock error, the pseudorange must be defined as p_i = (tr_i + b - t_i)c . The following is quoted from where the problem occurs. "Now the receiver has four measurements (the received time of the four messages) and four unknowns - the x, y and z coordinates of position and time t. Since the receiver already has a clock, what is solved for is not the actual time the messages arrived, but the clock bias b, which is the amount by which the receiver's clock is off. Let the coordinates of each satellite, and the time the message was sent, be [x_i, y_i, z_i, t_i] for i = 1, . . ., 4, the received time be tr_i for i = 1, . . ., 4, and c be the speed of light. Then the distance to each satellite should correspond to the signal travel time:

These equations are often written in terms of a pseudorange, which is simply the range computed without the clock correction included, or ." —Preceding unsigned comment added by RHB100 (talk • contribs) 03:12, 24 July 2008 (UTC)[reply]

Hello. On this edit, I think you changed the sentence to reduce the tensity of the situation. Anyway, I was just going to ask you if it's alright if I change it to the sentence before—since it looked like a nice form of literature. :-) No offence. Anyway, it would look like this:

During the Middle Ages, the descriptions of Ibn Sahl, Robert Grosseteste, and Ibn Al-Haytham made monumental advances in not only the understanding of light and the law of refraction, but also the magnifying properties that abide by those laws.^[1]

Your's looks like this:

Studies of properties of lenses and refraction in the Middle Ages[1] by scholars such as Ibn al-Haytham and Robert Grosseteste laid the groundwork for the development of telescopes.

Sincerely, InternetHero (talk) 09:17, 1 August 2008 (UTC)[reply]

Thank you for handling that. I got stuck on confrontation mode before I could back off enough to see where the actual misunderstanding was. Your explanation was very patient and lucid. - Eldereft (cont.) 08:15, 4 August 2008 (UTC)[reply]

To: Lou Scheffer

You have made the statement, "Also, in practice, receivers use additional clues (doppler shift of satellite signals, last known position, dead reckoning, inertial navigation, and so on) to give degraded answers when fewer than four satellites are visible."

in the Method of Operation section of the Global Positioning System article.

I do not believe it is true that GPS receivers in general use inertial navigation as you state. Military systems sometimes have both GPS and INS but I do not believe this is true in general for non-military systems as you state. Where is your reference to show that GPS receivers in general are supplemented with inertial navigation information? I am also skeptical with regard to the extent these other methods you mention are used. RHB100 (talk) 21:00, 21 August 2008 (UTC)[reply]

These methods are quite common, particularly in GPS built into cars. You can see it work quite easily - the map moves continuously when you go under a highway bridge, where a hand-held GPS will show there is no signal. In the built-in units, the car helps the GPS by telling how far it has gone since the last fix. The GPS extrapolates from the last fix and direction (dead reckoning)[4][5] or sometimes uses a gyroscope (or sometimes the car's steering wheel angle) to detect changes in direction [6]. This is a simple form of INS. Military systems, as you point out, often couple GPS with a sophisticated INS. LouScheffer (talk) 11:22, 22 August 2008 (UTC)[reply]

OK, thank you these references although lacking in some areas do have some good material. And you have provided a good explanation. You can call the system you describe as a simple form of INS if you want. I won't argue at least for now. The word inertial suggests to me that an INS must have an accelerometer but I guess it doesn't make too much difference.RHB100 (talk) 00:51, 23 August 2008 (UTC)[reply]

To: Lou Scheffer

You have stated as a reason for one of your edits to the GPS article that, "The problem with 3 satellites is not that there are two intersections, but that the distances are uncertain since the timing is unknown."

I think that it is certainly not the case that there is either one problem or the other. Actually the fact that are two intersections is a problem in addition to the problem that there is a clock error. The problem with your approach is that you start talking about the errors before the fundamental concept has been explained. It is better to explain the fundamental concept of GPS to the readers before explaining the clock error and the topic, Correcting the GPS Receiver Clock Introduction.

Also I think saying " using geometry and trigonometry" with a reference to [trilateration] does not satisfy the scientific curiosity of the readers. It is better to explain the fundamental concept rather than leave them bewildered knowing nothing more than that it has something to do with geometry and trigonometry. RHB100 (talk) 22:10, 21 August 2008 (UTC)[reply]

The "GPS Guide for Beginners", December 2008, Revision A, part number 190-00224-00 produced by Garmin explains on page 8 how a fourth satellite enables the GPS receiver to resolve the ambiguity associated with the two point intersection of three sphere surfaces. RHB100 (talk) 19:06, 25 August 2008 (UTC)[reply]

Also it is stated in [7] that "But if you want to calculate the altitude of an airplane or how high some mountaineers have climbed, you need a fourth satellite to yield that dimension.] It should be kept in mind that GPS receivers include all GPS receivers, those used for military purposes and for any other purpose." RHB100 (talk) 20:06, 25 August 2008 (UTC)[reply]

Your statement, "In other words, the receiver uses four measurements to solve for four variables: x, y, z, and t." is extremely misleading. There are many people who operate under the delusion that anytime you have four equations you can solve for four unknowns. This is true for the case of four independent linear equations but it is not true in general. With your misleading statement, you perpetuate this delusion. RHB100 (talk) 20:31, 25 August 2008 (UTC)[reply]

I agree that you cannot always solve 4 equations for 4 variables, in general. But in GPS you can, by design, and it's exactly what the receiver does. The fact that there are other systems of equations that cannot be solved this way is not relevant here, since we are explicitly talking about GPS. At least this is the way I read it. Clearly you read this differently. Let's add it to the talk page and see what others think. LouScheffer (talk) 20:43, 25 August 2008 (UTC)[reply]

About the edit you've undone in the GPS article. "It might seem that three satellites would be enough" (for calculating the position) No, it might not. Please, this is not trilateration as you undid my edit and put the reference to it again; and it's not like "3 satelites to solve 3 variables xyz and 4 satelites to solve xyzt".

I dont want to go much deep here, but it's 4 satellites for 3 dimensions as an analogue situations would need 3 points for 2 dimensions, 2 points for 1 dimension and so on. This is about Locus. Time is some quite more complex thing you're putting in, and it gets more precise with the more satellites you have. But having more satellistes has the only function of increasing precision - if we had a planck time clock we would need 4 satellites and that's it.

Well, you see, two people have undone my edits so far, none of them seemed to understand too much about satellites (a guy that did understand something about the matter said my images were good illustration, maybe he isnt a much good Professional Engineer in the field of Control System Engineering or wrote Philosophy on How GPS Article Should be Written just to play with people). The other guy that undone my edit just didnt answer when I asked the reasons for his undo - just as I don't really expect that you'll answer me at all. Anyway, I'll probably just give up as It seems my text is just too poor for this and people don't want to be bothered with the geometry behind the GPS concept. Almighty001 (talk) 16:26, 5 November 2008 (UTC)[reply]

The statement "In other words, the receiver uses four measurements to solve for four variables: x, y, z, and t." is cute but not informative. The receiver needs 4 measurements of time message sent, 4 measurements of time message received, and 2 measurements of distance of intersections to earth just to name a few. There is no basis for saying there are 4 measurements and 4 unknowns other than to come up with a cute sounding statement. The term user-friendly is trite, uninformative, and sounds like an ad for juveniles. Don't you understand that the readers have enough sense to tell if it is user friendly or not. This unsophisticated language is certainly not needed.RHB100 (talk) 00:46, 10 November 2008 (UTC)[reply]

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