text:
Talk:Engineering Acoustics/Car Mufflers

 * Engineering Acoustics/propagation of the wave in specific condition now redirects here. You can view its edit history.

Comments from Talk:Engineering Acoustics/propagation of the wave in specific condition
This page appears elsewhere. You should delete this one and remove it from the list. Find a title that is more appropriate. Coordinate with Joel Leonardi, who is also working on automobile mufflers. Please get help with proofreading from the writing center. --me513

Engineering Acoustics/propagation of the wave in specific condition is redirected here
I redirected it because that module seemed to be an abandoned module about car mufflers, and this is the current one. --Kernigh 16:56, 6 February 2006 (UTC)

title: Talk:Engineering Acoustics/Car Mufflers


text:
Help:Editing

Wikibooks is a wiki, which means that anyone can easily edit any unprotected page and save those changes immediately to that page. After your first edit, you are a Wikibooks editor! To request a change to a protected page, you may add your suggestion to the talk page. If you just want to experiment, please do so in the sandbox.

Editing a Wikibooks page is very easy. Simply click on the Edit tab at the top of a Wikibooks page. This will bring you to a new page with a text box containing the editable text of the original page. Once you're done, write a short edit summary in the small field below the edit box. You may use shorthand to describe your changes, and when you have finished, press the Show preview button to see how your changes will look. You can also see the difference between the page with your edits and the previous version of the page by pressing the Show changes button. If you're satisfied with what you see, be bold and press the Save page button. Your changes will immediately be visible to other Wikibooks users.

Composition of an edit page
The editing page consists of these sections:

 * Edit toolbar
 * Editing text box
 * Edit summary box
 * Minor edit, Watch this page checkboxes
 * Save page, Show preview, Show changes buttons
 * Cancel, Editing help links
 * A list of templates used on the page
 * A preview, if you have requested one. Your preferences may place the preview at the top of the page instead.

Edit toolbar
The edit toolbar above the editing text box helps you produce wiki markup, instructions used to stylize text on a wiki page. In the edit toolbar above the editing text box seen when editing a page, if you click Help you can see what effects are possible with wiki markup. Another way you can learn how to produce specific effects is to click Edit on a page that contains the effect you wish to copy and see what markup is used.

Edit summary
An edit summary is a brief explanation of an edit to a Wikibooks page. When you edit a page, there is a small text entry field, which is labeled "Edit summary", located under the main edit box and above the "Save page" button. Edit summaries are displayed in lists of changes (such as page histories and watchlists), and at the top of diff pages.

It is good practice to fill in the "Edit summary" field, or add to it in the case of section editing, as this helps others to understand the intention of your edit. To avoid accidentally leaving edit summaries blank, you can select "Prompt me when entering a blank edit summary" on the Editing tab of your user preferences, if you have created an account.

Always provide an edit summary
It is considered good practice to always provide an edit summary, but it is especially important when reverting the actions of other editors, or if you delete any text; otherwise, people may question your motives for the edit.

Accurate summaries help other editors decide whether it is worthwhile for them to check a change, and to understand it if they choose to check it. Summaries are less essential for "minor changes", but a summary like "fixed spelling" is helpful even then.

Qualities of good summaries

 * Summarize. Summarize the change, even if only briefly; even a short summary is better than no summary.
 * Explain. Give reasons for the change, if there is a reasonable chance that other editors may be unclear as to why it was made.
 * Abbreviations. Experienced users, especially those with many edits to make, will often use abbreviations in order to save time; for example, "rv" for "revert", or shortcuts for Wikibooks policies and related pages, e.g., "WB:WIW" for What is Wikibooks (see Shortcuts). Abbreviations should be used with care, although they save one editor time they may cost readers much more time to figure out what they mean, they can be confusing for inexperienced users, but they are generally fine for small edits such as formatting and grammar changes.
 * Talk pages. When editing talk pages, consider copying your comment to the edit summary, especially if it is brief; this allows users to check Recent changes, Page history and User contributions very efficiently. It also reduces the load on the servers.
 * Harmony between text and edit summary. Make sure that important information is not only included in the edit summary. This applies especially on talk pages. Readers who only see the text may miss that important information, and they may then respond inappropriately through no fault of their own. Try to prevent misunderstandings. If an edit requires more explanation than will fit in the edit summary box, use the Discussion page instead, and put in the edit summary "see talk" or "see discussion".
 * Avoid misleading summaries. Mentioning one change but not another one can be misleading to someone who finds the other one more important; add "and misc." to cover the other changes.
 * Avoid inappropriate summaries. Editors should explain their edits, but not be overly critical or harsh when editing or reverting others' work. This may be perceived as uncivil, and cause tension or bad feelings, which makes collaboration more difficult. Explain what you changed, and cite the relevant policies, guidelines, or principles of good writing, but try not to single out others in a way that may come across as an attack.

Properties

 * Limited to 200 characters. The edit summary box can hold one line of 200 characters. If you attempt to type or paste more, only the first 200 characters will be displayed—the rest will be discarded. For example attempting to add 10 new characters (at the end or in between) to a summary already containing 195 characters will result in the first 5 new characters being inserted and the second 5 being disregarded.
 * Can be previewed. The "Show preview" button also provides a preview of the edit summary to facilitate checking links.
 * Can't be changed after saving. After you save the page, you cannot change the edit summary.
 * Doesn't appear in searches. The search function cannot search edit summaries, and they are not indexed by external search engines.
 * Wikilinks always rendered; other wikitext coding ignored. Text in edit summaries renders internal links, including piped links, and interwiki links, even when enclosed within and  . Therefore, copying wikitext in the edit summary box may be preferable to copying text from the preview, except when one wants to save space. Other wikitext coding is not interpreted.
 * URLs. When copying an external link from the preview into the edit summary box then, depending on the operating system, the "printable version" is copied, i.e., how it is normally rendered, and in addition, between parentheses, the URL; hence the same information as in the wikitext, but in a different format, as well as a possible sequential number.

Minor edit checkbox
A check to the minor edit box signifies that only superficial differences exist between the current version and the previous version. Examples include typographical corrections, formatting and presentational changes, rearrangement of text without modification of content, etc. A minor edit is one that the editor believes requires no review and could never be the subject of a dispute, such as changing "teh" to "the". An edit of this kind is marked in its page's revision history with a lower case, bolded "m" character (m).

By contrast, a major edit is one that should be reviewed for its acceptability to all concerned editors. Therefore, any change that affects the meaning of a page is not minor, even if the edit concerns a single word; for example, the addition or removal of "not", which can change the meaning of a sentence, is a major edit.

Because editors may choose to ignore minor edits when reviewing recent changes, the distinction between major and minor edits is significant. Logged-in users might even set their preferences to not display minor edits. If there is any chance that another editor might dispute a change, it is best not to mark the edit as minor.

Users who are not logged in to Wikibooks are not permitted to mark changes as minor because of the potential for vandalism. The ability to mark changes as minor is one of many reasons to register.

A good rule of thumb is that edits consisting solely of spelling corrections, formatting changes, or rearrangement of text without modification of content should be flagged as minor edits.

When to mark an edit as a minor edit

 * Spelling and grammatical corrections.
 * Simple formatting (e.g., capitalization, punctuation, or properly adding italics to non-English words, like folie des grandeurs).
 * Formatting that does not change the meaning of the page (e.g., moving a picture, splitting one paragraph into two—where this is not contentious).
 * Obvious factual errors (e.g., changing "Nixon resigned in 1874" to "Nixon resigned in 1974").
 * Fixing layout errors.
 * Adding or correcting wikilinks, or fixing broken references already present in the page.
 * Removing vandalism and graffiti.

Things to remember

 * Any change to the source text, even if it does not affect the presentation of the page in HTML (if it involves adding a space or a line break, for example) will still be treated as a change according to the database.
 * Marking a major change as a minor one is considered poor etiquette, especially if the change involves the deletion of some text.
 * Reverting a page is not likely to be considered minor under most circumstances. When the status of a page is disputed, and particularly if an edit war is brewing, then it is better not to mark any edit as minor. Reverting blatant vandalism is an exception to this rule.
 * If you accidentally mark an edit as minor when it was in fact a major edit, you should make a second edit, or dummy edit, noting in the dummy's edit summary that the previous edit was major. As a trivial edit to be made for this purpose, just opening the edit box and saving (i.e. changing nothing) will not work; neither will adding a blank space at the end of a line or a blank line at the end of the page—in these cases the edit is cancelled and the edit summary discarded. However, one can, for example, add an extra space between two words. This will be preserved in the wikitext and recorded as a change, although it will not change the page's appearance when rendered.
 * It may be worth communicating any disagreement about what is minor via Talk or a message to the contributor, being careful to avoid a flame war ("I thought your change was a bit more than minor—maybe I am being over-sensitive?"). There is a grey area, and many contributors will appreciate feedback on whether they've got it right.
 * Marking your change as minor affects how it displays in some editors' watchlists. If, for example, you mark your talk page comments as "minor", then fewer editors are likely to notice your comment.

Exceptions
Administrators and reviewers can semi-automatically revert the edits of the last editor of a page; all such rollback reversions are marked as minor by the wiki software. The intended use of the rollback feature is for cases of vandalism, where the act of reverting any vandalism should be considered minor (and can be ignored in the recent changes list).

Show preview button
Below the edit box is a Show preview button. Pressing this will show you what the page will look like without actually saving it. It is strongly recommended that you use this prior to saving. This allows you to check what the page will look like first and to check that you haven't made any errors. It also prevents the need for multiple saves. Saving the same page numerous times in quick succession makes it harder for people to check what changed, and clogs up the page history.

It is helpful, to save the page before moving, breaking apart, or combining sections of the page, if you have been making small edits to the page. The difference display is not good at showing paragraph moves, and will not display the small edits clearly if sections are then moved around.

Saving only once is also a way of avoiding edit conflicts, as people will not see the page on recent changes, and therefore they are less likely to try editing it at the same time as you.

If you are logged in, you can set your preferences to show the preview before the edit box instead of after it. If you select this option, the preview will be displayed above the edit box when you click the "Show preview" button while editing a page. See Help:Account management.

Using show preview also prevents your login timing out, which would mean your edits would not be attributed to your username. Clicking preview regularly will restart the timer, so you remain logged in. Also, if you are no longer logged in, showing a preview will make you aware of this so you can log in and save your work after that. You can check this by seeing if your username appears in the upper-right corner when you press preview. If you are not logged in, open Special:UserLogin in a separate window (right-click "Log in" and hit "Open link in new window" or similar). Log in, then go back to your editing and hit "preview" again to make sure all is well. Note that this will clear the minor edit and watch checkboxes, so make sure they're set appropriately again before you finally save the page.

When utilizing this feature during a major edit, consider copying the content into your clipboard. On extremely rare occasions, the Wikibooks servers have hiccups, and you could lose your work.

When pressing "Show preview", a preview of the edit summary is also obtained; thus (for example) links can be checked.

Sections
Sections are created by creating their headings, as below.

Sub-subsection
Please do not use only one equals sign on a side ( =Heading= ). This would cause a section heading to be as large as the page's name (title).

Heading names of sections (including subsections) should be unique on a page. Using the same heading more than once on a page causes problems:
 * An internal link (wikilink) to a section, in the form Pagename, will only link to the first section on the page with that name, which may not be the intended target of the link. See section linking on linking to a section.
 * When a section with a duplicate name is edited, the edit history and summary will be ambiguous as to which section was edited.
 * When saving the page after a section edit, the editor's browser may navigate to the wrong section.

Table of contents (TOC)
For each page with more than three section headings, a table of contents (TOC) is automatically generated from the section headings, unless:
 * (for a user) preferences are set to turn it off
 * (for a page) the magic word   (with two underscores on either side of the word) is added to the page

Positioning the TOC

When either   or    (with two underscores on either side of the word) is placed in the wikitext, a TOC is added even if the page has fewer than four headings.

With  , the TOC is placed before the first section heading. With  , it is placed at the same position where this code is placed. There may be some introductory text before the TOC, known as the "lead". Although usually a heading after the TOC is preferable,   can be used to avoid being forced to insert a meaningless heading just to position the TOC correctly, i.e., not too low.

Floating the TOC

The TOC can, in some instances, be floated either right or left using TOC right or TOC left when it is beneficial to the layout of the page, or when the default TOC gets in the way of other elements. Before changing the default TOC to a floated TOC, consider the following guidelines:

 * 1) If a page will be adversely affected by the change, don't float the TOC.
 * 2) When floating a TOC, check whether the page layout will be harmed if the TOC is hidden by the user.
 * 3) Long lists may create very long TOCs. The TOC should not be longer than necessary, whether it is floated or not.  Limiting the depth of the TOC can be used to reduce the length of the TOC by hiding nested subsections, rather than using a floating TOC (see below).
 * 4) The default TOC is placed before the first headline, but after any introductory text (unless changed by the page's editors). If the introductory summary is long enough that a typical user has to scroll down to see the top of the TOC, you may float the TOC so it appears closer to the top of the page.
 * 5) Floating a wide TOC will produce a narrow column of text for users with low resolutions. If the TOC's width exceeds 30% of the user's visible screen (about twice the size of the Wikibooks navigation bar to the left), then it is not suitable for floating. (Percentages assume a typical user setup.)
 * 6) If the TOC is placed in the general vicinity of other floated images or boxes, it can be floated as long as the flowing text column does not become narrower than 30% of the average user's visible screen width.
 * 7) A left-floated TOC may affect bulleted or numbered lists.

Limiting the depth of the TOC

When a page has a very large number of subsections (such as this page), it may be appropriate to hide lower-level subsections from the TOC. You can specify a limit for the lowest-level section that should be displayed using, where n is the number of = signs that are used on each side of the lowest-level section header that should be displayed (e.g. 3 to show ===sections=== but hide ====sections====). The limit=n parameter can also be given to TOC left or TOC right the same way.

Linking to the TOC

You can make a link to the TOC using the following:
 * Same page:
 * wikicode: Contents
 * link: Contents
 * Different page:
 * wikicode: Contents
 * link: Contents of Templates Help page

Sections vs. separate pages
Advantages of separate pages:
 * 1) what links here feature
 * 2) separate edit histories
 * 3) some template limits apply per page
 * 4) automatic redirect on renaming
 * 5) loading one small page is faster than loading one large page—but are readers more likely to want to use just one section or to browse many of the sections of the topic?—see advantages of combined pages
 * 6) one small page is easier to navigate than one large page—but see above
 * 7) can separately be put in categories

Advantages of one combined page with sections:
 * 1) loading one combined page is faster and more convenient than loading several divided ones
 * 2) searching within one large page or its wikitext with a local search function is faster and has advantages over searching several pages using the site search engine or a web search engine
 * 3) the automatic table of contents provides for convenient navigation.
 * 4) more likelihood of editorial cohesion of a concept compared to having several pages likely to be independently edited
 * 5) duplication of items relevant to each section is avoided

Links
Links give readers one-click access to other Wikibooks pages, other Wikimedia projects, and external websites.

Wikilinks
A wikilink or internal link links a page to another page within English Wikibooks.

 * Main Page gives Main Page (link to Main Page, labeled Main Page).
 * Home gives Home (link to Main Page, labeled Home).
 * Main Pages gives Main Pages, just like Main Pages does: Main Pages.
 * Homes gives Homes, just like Homes does: Homes.
 * Main Page's gives Main Page's (punctuation is not appended to the link).
 * Main Page s gives Main Page s.
 * Main Pages gives Main Pages.
 * Main Pages gives Main Pages.
 * Cookbook s gives Cookbook s.

Links with a specified label are said to be "piped" because of the pipe symbol used ( | ). For certain types of link, the label will be generated automatically if a pipe is typed with no label after it (thus saving you typing). See piped links below.

The link target is case-sensitive except for the first character (so calculus links to Calculus, but CAlculus does not).

If the target of a wikilink does not exist, it is displayed red, and is called a red link. If a red link is clicked, the user is taken to a page where it is possible to create a page under the red-linked title. Red links to a particular (non-existent) title can be detected using the What links here feature.

If the target of a link is the same as the page on which it appears (a self-link), it is displayed in bold, as in Help:Editing.

Attempting to link normally to a file page, category page or interlanguage link will produce a different effect: it will place the image on the page, add the page to the category or create an interlanguage link at the edge of the page. To override this behavior, add an initial colon, as in,  ,.

Piped links
A piped link is an internal link or interwiki link where the link target and link label are both specified. This is needed in the case that they are not equal, while also the link label is not equal to the link target with the last word extended. This allows linking a word or phrase within the text of a page rather than using "see also", even if the wording does not exactly correspond with the name of the target page. With a suitable browser and depending on the preferences set, one can still see the link target: when you point at the link, the name shows up in a hover box and is also shown in the status bar.

For instance: Help will show as Help.

If in a piped link the part after the "|" is left empty, it is converted to an abbreviated form of the page name on the left, as follows:

 * 1) any word before the first colon, as well as the colon itself, is removed. This word may or may not be a namespace prefix (such as "Help:") or an interwiki prefix (such as "commons:").
 * 2) if there is text in parentheses at the end it will be removed
 * 3) if there are no parentheses but there is a comma, the comma and everything after it is removed
 * 4) the link will be in whatever case is used.

Just like for the four tildes when adding a signature, in a preview, the result already shows up in the preview itself, but the conversion in the edit box is not yet shown. Press "Show changes" to see the change in the wikitext.

Colon
 * Help:Templates is converted to Templates, which is rendered as Templates
 * Programming:C++ is converted to C++, which is rendered as C++ - even though "Programming:" is not a namespace the shortcut works anyway
 * Key Largo (film) is converted to Key Largo, which is rendered as Key Largo

Case
 * pipeline (Unix) is converted to pipeline which is rendered as pipeline.
 * Pipeline (Unix) is converted to Pipeline (Unix) which is rendered as Pipeline.

Comma
 * Boston, Massachusetts is converted to Boston, which is rendered as Boston.

Subpage links
Subpages can be linked to with relative links, without giving the full page name. The following example shows how we link to various pages from the hypothetical. Note that that the full page name in the link title can be suppressed by appending another slash. For more flexibility, use a piped link as normal.

Note that the first character of sub-pages is case-sensitive.

Section links (anchors)
To link to a section in the same page you can use:  displayed text , and to link to a section in another page:  displayed text .

The section title in fact points to an "anchor" on the target page. It is possible to define anchors other than explicit section titles, using the template. However  and   are reserved names that link to the top of a page and the table of contents, respectively.

Section links still work if the wikilink is a redirect (for example, if Help:About redirects to Welcome, then Help:About will link to the "General Information" section of Welcome). It is also possible to put section links inside redirects. For example, WB:LINK redirects to Help:Editing. Note that an explicit section link overrides any section link in a redirect, so WB:LINK will go to the "Interwiki links" section of this page. Anchor links can also be added to external links and to interwiki links, again using the # syntax.

Interlanguage links
Interlanguage links are links from any page at here at the English language Wikibooks to nearly equivalent or exactly equivalent pages in another language Wikibooks.

The interlanguage links take the following form:

 * language code:Title

where the language code is the two-letter code as per ISO 639-1. (See Complete list of language Wikibooks available. English is "en", Japanese is "ja", etc.) So for example in the English language book on Calculus, which is available on many other wikis, the interlanguage links might look like this:

 * 解析学基礎
 * Analyse
 * 微积分学

Note: These links are treated specially, and don't show up in the body of the text, but rather in a special sidebar section "in other languages" listed by language name. Technically they can go anywhere in the page; placement does not alter the visual appearance of the links on the rendered page except for the order. However, the convention is to put them at the bottom of the wikitext.

Interwiki links
An interwiki link links to a page on another Wikimedia project website, such as Wikipedia or another language Wikibooks. Other sites are listed in the interwiki map. These links have the same ... syntax as wikilinks (see above), but take a prefix which specifies the target site. For example, w:Help:Contents links to the "Help:Contents" page on Wikipedia. Links can be piped as with wikilinks. Remember that an interlanguage link should be preceded by a colon if it is to be displayed where it appears in the text; otherwise it will be listed at the side of the page (which is appropriate only if it is the most closely corresponding page in the other language Wikibooks).

Interwiki links (like external links) are displayed in a slightly paler blue than ordinary wikilinks. MediaWiki does not detect whether these target pages exist, so they are never displayed red. The interwiki links for the major Wikimedia projects are shown at right.

Some people prefer to use templates that wrap the above interwiki link syntax with some nice formatting -- Wikipedia, Wikipediapar, Wikipedia-inline, Wikiversity, Wikisource, Wikiquote, Wikivoyage, etc.

Inserting references
Single citation of a reference or footnote

At the point of citation in the page, enter the footnote or reference like this:

You can include formatting and links in the footnote or reference in the usual way. The reference becomes visible in the

The template reflist is an alternative, mostly used if there are many footnotes.

Multiple citations of the same reference or footnote

To cite the same reference or footnote several times, identify it using the  parameter of the   tag.

At one of the citation points (it makes sense to choose the first), enter the reference like this:

Then at all the other citation points, just enter:

You are free to pick any footnote name, subject to a few rules. The footnote name is internal and will not be displayed anywhere when the page is viewed. Footnote names are case sensitive and may not be a numeric integer. Names and groups should be kept simple and restricted to the standard English alphabet and numerals.

Using templates to insert reference text

A number of templates, such as a generic citation, or more specific cite book, cite web, etc., are available to format the text between  and   tags in a more structured way. These are listed at Category:Citation templates. Their use is optional: they do aid with consistent formatting, but on the other hand they can make editing more cumbersome.

Appearance of references
The  tags in the main text are converted to auto-numbered superscripts, like this:

Clicking on a numbered superscript takes you straight to the text of the corresponding footnote or reference.

The  tag is expanded to show the text of the footnotes or references against their corresponding numbers, like this:

{| class="wikitable"

This part of the text requires clarification, whereas the entire text is cited.

 * Notes

The quick brown fox jumps over the lazy dog.

This can also be done using the reflist template with a refs parameter. If desired, the group parameter can be used to group references for the template:

How razorback-jumping frogs can level six piqued gymnasts.

 * Notes

 * References

Lists
There are three types of lists: unordered lists, ordered lists, and definition lists.

For simplicity, list items in wiki markup cannot be longer than a paragraph. A following blank line will end the list and reset the counter on ordered lists. Separating unordered list items with blank lines may look approximately normal on your screen, but it creates many separate one-item lists, which is a problem for people using screen readers, causing accessibility problems for people with disabilities.

Other items

 * Categories
 * Files
 * Tables
 * Templates

Reverting
On Wikibooks, reverting means undoing the effects of one or more edits, which normally results in the page being restored to a version that existed sometime previously. More broadly, reverting may also refer to any action that in whole or in part reverses the actions of other editors.

This page contains technical information about making reverts. It should be borne in mind, however, that reverting good-faith actions of other editors (as opposed to vandalism) is considered disruptive when done to excess, and can even lead to the reverter being blocked from editing.

Manual reverting
In some cases (for example, if a vandal added or removed text, and unrelated constructive edits have been made since), the easiest way to undo past edits may simply be to edit the current page, deleting wrongly added text or restoring wrongly deleted text (this can be copied and pasted from a past version of the page). However, it may be more convenient to restore a particular old version of the page from prior to the changes you wish to revert. To do this:
 * Click the "history" tab at the top of the page to display the page history.
 * Click the time and date of the earlier version to which you wish to revert. You will see a phrase similar to: "This is an old revision of this page, as edited by ***.***.***.*** (talk) at 15:47, January 24, 2024. It may differ significantly from the current revision."
 * Important: in the case of vandalism, take the time to make sure that you are reverting to the last version without the vandalism; there may be multiple consecutive vandal edits or they may be interspersed between constructive edits.
 * Click the Edit tab as you normally would to edit a page. (Above the edit box, you will see a warning similar to: "You are editing an old revision of this page. If you save it, any changes made since then will be removed.") If editing requires a registered account, log in first, or leave a note on the discussion page.
 * Complete the edit summary field (the abbreviation "rv" can be used to stand for "revert"; the edit summary "rvv" means "reverting vandalism").
 * Save the page.
 * If constructive edits had been made after those that you wished to revert, return to the page history to find those edits, and redo them by hand if reasonably possible.

If reverting vandalism, check the contribution history of the user who vandalized the page. If this user is vandalizing many pages, report them.

Undo
The MediaWiki software sometimes enables editors to easily revert (or "undo") a single edit from the history of a page, without simultaneously undoing all constructive changes that have been made since. To do this, view the page history or the diff for the edit, then click on "undo" next to the edit in question. The software will attempt to create an edit page with a version of the page in which the undesirable edit has been removed, but all later edits are retained. There is a default edit summary, but this can be modified before saving.

It is also possible to undo several consecutive edits, even if they conflict among themselves: view the diff to be removed (by selecting the two extremal revisions in the history and clicking "compare selected revisions"), and click the "undo" link.

This feature removes the need to manually redo useful changes that were made after the edit which is being reverted. However, it will fail if undoing the edit would conflict with later edits. For example, if one edit adds a paragraph and a later edit modifies that paragraph, it will be impossible to automatically undo the earlier edit. In this case, you must determine how to resolve the problem manually.

Rollback
Administrators and reviewers who have been granted access to the rollback feature have additional links which:
 * appear only next to the top edit
 * revert all top consequent edits made by last editor
 * work immediately, without the intermediate confirmation diff page
 * add automatic edit summary "m Reverted edits by Example (talk) to last version by Example2", marking edit as minor

Rollback links appear on the user contributions pages, user watchlists, history pages and diff pages. Note that in the last case, rollback links can be misleading, since reversion is not necessarily to the old version shown (the diff page may show the combined result of edits, including some by other editors or only part of the edits the rollback button would revert). To see the changes the rollback button will revert, view the specific diff that compares the last version from the last editor with the last version from the previous editor.

Rollback works much quicker than undo, since it:
 * allows reverting without even looking at the list of revisions or diff
 * does not require loading an edit page and sending the wikitext back to the server
 * does not require a click of the save button

On the other hand, it is not as versatile as undo, since it does not allow specification of which edits have to be undone. One may want to revert more or less edits than the rollback does or edits which do not include the last edit. It also does not allow adding an explanation to the automatic edit summary and it should only be used to revert obvious vandalism.

Rolling back a good-faith edit, without explanation, may be misinterpreted as "I think your edit was no better than vandalism and reverting it doesn't need an explanation". Some editors are sensitive to such perceived slights; if you use the rollback feature other than for vandalism (for example, because undo is impractical due to the large page size), it is courteous to leave an explanation on the book's discussion page or on the talk page of the user, whose edit(s) you have reverted.

If someone else edited or rolled back the page before you clicked the "rollback" link, or if there was no previous editor, you will get an error message.

Redirecting
Redirecting a page causes navigation to a given title to take the reader directly to a different page. The page the reader visits first is called the redirect page.

Syntax of redirects
A page will be treated as a redirect page if its wikitext begins with <tt>#REDIRECT</tt> followed by a valid wikilink or interwiki link. A space is usually left before the link. (Note that some alternative capitalizations of "REDIRECT" are possible.) The button in the edit toolbar can be used to produce this syntax.

Note that a redirect will only work as intended (i.e. take the reader directly to the target page) if the link is to an existing normal page (not a special page) on the same project (English Wikibooks). In other cases soft redirects are often used – see below.

Examples:
 * <tt> #REDIRECT Help:Tracking changes </tt> (redirects to the Help:Tracking changes page)
 * <tt> #REDIRECT Help:Tracking changes </tt> (redirects to the "Preferences" section of the Help:Tracking changes page)
 * <tt> #REDIRECT fr:Help:Tracking changes </tt> (appears as a redirect to the Help:Tracking changes page on French Wikibooks, but will not work as a true redirect; this is called a "soft redirect")

Any text appearing after the redirect link will be ignored in the display, but may be used to add categories, comments, etc.

Note that the redirect link must be explicit – it cannot contain variables, templates, etc.

When redirecting to a category page, prefix the target pagename with a colon to prevent the redirect from showing up in the category. (Redirects from one category page to another should use soft redirects—see below.) Redirects to file pages also require the colon.

Appearance of redirects
If the redirect target is an existing page on English Wikibooks, then if a reader navigates to the redirect page—by means of a wikilink or a URL—they will be taken directly to the target page. However, the browser still shows the URL of the redirect page, and the target page shows a small notice below the top title to indicate that you arrived by means of a redirect. For example, if you click WB:RR, you will be redirected to the Reading room page, and the top of the page will look like:

<blockquote style="background-color: white; color: black; border:1px solid black; padding: 1em;"> <div class="firstHeading" style="color: #000000; background: none; overflow: hidden; page-break-after: avoid; font-size: 1.8em; font-family: 'Linux Libertine',Georgia,Times,serif; margin-top: 1em; margin-bottom: 0.25em; line-height: 1.3; padding: 0; border-bottom: 1px solid #AAAAAA;">Wikibooks:Reading room (Redirected from [ Wikibooks:RR] )

To get the canonical URL of the target page in your browser's address bar, click the page's tab. To go to the redirect page itself (to edit it, view its history, etc.), click the link in the "(Redirected from...)" notice.

If the redirect target is a non-existing page (redlink), or a special page, or a page in another project, then the redirect is not followed, and the reader sees the display of the redirect page (as illustrated below). If the target is a non-existent section of an existing page, then the redirect will take the reader to the top of the target page.

Note that chains of redirects are not followed. If title A redirects to B, and B is itself a redirect page, then a reader navigating to A will see the display of the redirect page B (as illustrated above). This situation is called a double redirect. (Bots fix such chains so that each redirect points directly to the final target page.)

Creation of redirects
A redirect page can be created like any other page. Simply type in the wikitext <tt> #REDIRECT xxx</tt>, replacing "xxx" with the title of the target page (optionally followed by a "#" sign and the section title). The button in the edit toolbar above the edit window can be used to save typing (either click it and then insert the desired target, or else type the target, select it with the mouse, then click the button). Make sure that there is no text before the #REDIRECT keyword, or the redirect will not work. There is not usually any reason to place any text after the link either, although sometimes categories (or categorizing templates) are added.

Similarly, any existing page can be edited to turn it into a redirect. If a new redirect page is created or an existing page turned into a redirect page, an edit summary will be automatically generated stating that the page has been redirected to the given target. (This is overridden if the editor supplies an edit summary.)

When a page is moved (renamed), a redirect is automatically created from the old to the new name, and also one for the corresponding talk page (if that was moved as well). Administrators can choose to suppress creation of the redirect.

If the new page name is occupied by a redirect that has only one edit in its history and targeted to the old page name, it is replaced by the page being moved. If the redirect has more than one history entry, or has a different target page, then the move must be made by an administrator.

To edit a page which is already a redirect (or to view its history, talk page, etc.), follow the redirect to the target page, then click on the link in the "(Redirected from ...)" notice at the top of the page. This will take you to the redirect page itself. Another way to get to a redirect page is to go to the target page, and click "What links here" (in the toolbox on the left of the page). This will show you all the back-links from that page, including redirects. Clicking on a redirect in this list will take you to the redirect page, not the target.

Soft redirects
As an alternative to the normal "hard" redirects (which take the reader directly to the target page), it is possible to create "soft" redirects, which leave the reader on the redirect page, giving them the option of clicking the link to the target page. This is usually done in the following situations:
 * When the target is on another project (Wikipedia, other language Wikibooks, etc.) or is a special page. (In these situations a hard redirect would behave as a soft one in any case.)
 * For redirects between categories. (Hard redirects will work for category pages, but soft ones are preferred because of the software's inability to recategorize pages from redirected categories.)

Soft redirects are created using the templates soft redirect and category redirect.

Page protection
Administrators are able to protect a page to restrict editing or moving of that page, and remove such protection. Protection can be indefinite, or expire after a specified time.

 * Full protection prevents editing by everyone except administrators.
 * Semi-protection prevents editing by unregistered contributors and contributors with accounts which are not autoconfirmed.
 * Creation protection prevents a page (normally a previously deleted one) from being recreated.
 * Move protection protects the page solely from moves.

Any type of protection or unprotection may be requested at Reading room/Administrative Assistance. Changes to a fully protected page should be proposed on the corresponding talk page. See Protected page for additional information.

Edit conflicts
If someone else makes an edit while you are making yours, the result is an edit conflict. Many conflicts can be automatically resolved by the Wiki. If it can't be resolved, however, you will need to resolve it yourself.

To understand what an edit conflict is, consider the following situation:

 * Alice clicks Edit on a page.
 * Bob clicks Edit on the same page, while Alice is editing.
 * Alice finishes her edits and clicks "Save page". The page is saved with Alice's version while Bob is still editing.
 * Bob finishes his edits and clicks "Save page". Bob gets an "edit conflict" page, because the software can't automatically reconcile the differences between Bob's and Alice's versions of the page. The edit conflict page gives Bob a chance to reconcile the differences manually.

Layout
At the top of the edit conflict page is an editing box containing Alice's version of the whole page, even if Bob is doing section editing.

At the bottom of the edit conflict page is a second editing box containing the text Bob was going to submit. This will be Bob's version of the page or section he was editing.

Between the two editing boxes is a diff that shows the difference between Alice's and Bob's version of the page. For the section Bob is editing it shows Bob's changes and Alice's possible changes, except for sections where Bob and Alice have both made the same change. For the other sections it shows the full new text as if all that text was added.

Bob can edit in the upper editing box and press Save.

Resolution
If Bob only made small changes, and Alice made large changes, he may choose to work from Alice's version, and re-merge his changes in. Bob might choose to add some text like "via edit conflict" to the edit summary to warn Alice and others that he had to do this—Alice can then review his merging for accuracy.

If Bob made large changes, and Alice made small changes, he may choose to work from his version. One option is for Bob to copy the bottom text into the top text (or just copy over the one section of the top text, if Bob was section editing), with an appropriate edit summary (e.g., "via edit conflict, will remerge"). Then Bob can view the page history, determine Alice's changes, and re-apply them to his version, in a separate edit.

If both Alice and Bob made large changes, matters become complicated, and Alice and Bob just have to do the best they can. For example, if both Alice and Bob simultaneously add a large section of text on the same subject, then it may be best for Bob to submit his changes, and then for Alice and Bob to both have a look at the two versions and decide between themselves which version is better.

Bob should not just post his changes over the top of Alice's. We assume good faith—mistakes are occasionally made, and newcomers may not understand the edit conflict window. However, Bob must not routinely ignore edit conflicts. It is absolutely not acceptable for Bob to overwrite Alice out of laziness. We encourage contributors to double-check their merges by using the diff feature.

Prevention
Because edit conflicts are irritating and time-consuming, you may choose to alter your editing habits so they happen less often.

One of the easiest ways is to edit the smallest portion of the page necessary. If you are only going to be editing a single section in the page, then click the "Edit" link for that section, rather than the "Edit" link for the entire page. Two people can be working on different sections at the same time, and there will be no edit conflict.

To reduce the chance of edit conflicts, Wikibooks also has an "In Use" notice in its Template namespace that people may use when editing a page over a long period of time. Simply put in use on a page before proceeding with a major edit, and remove the template when the editing is complete.

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

title: Help:Editing


text:
User:D0li0

Hello World...

WikiPedia:User:D0li0, WikiBooks:User:D0li0, MetaWikiPedia:User:D0li0, SeattleEVA.org, eaa-phev.org

title: User:D0li0


text:
Accountancy/Quick Reference

text and cases 9th edition by anthony,reece,hertenstein Alfredson, Lero, Picker,Loftus, Clark. Apply International Accounting Standards, 2nd Edition, Wiley IAS 7 16 etc. all IAS standards

 * Accounting Ratios

title: Accountancy/Quick Reference


text:
User talk:Sshibata

Image:Matlab.png
You did not specify license of this image. You should have seen warning on upload page: we delete image with unknown source and copyright status. Please fix images you uploaded. Read Image use policy and Image copyright tags or leave me a message if you have any questions. --Derbeth talk 10:21, 28 November 2005 (UTC)

Welcome message
Hello, and welcome to Wikibooks!

Here are some tips to help you get started:
 * To learn the wiki-markup-language syntax, see Help:Editing.
 * Make sure to sign your posts and comments with four tildes, like this: ~~~~
 * There is a box at the top of the edit window (if javascript is enabled on your browser) that will insert it too (looks like part of a signature). This will let others know who left it, and make it easy to reply back to you.
 * Remember to conduct any editing experiments in the sandbox (global to the system) or in a page on your own userspace.
 * You can tell the community something about yourself in your userpage.
 * You can get to this page by clicking the tab at the top of the page labeled with your registered username.
 * Wikibooks is a collection of open-source textbooks. (What is Wikibooks).
 * If you are a Wikipedian, see Wikibooks for Wikipedians for a primer on how things work here (it's a little different).
 * If you want to base your work here on materials from Wikipedia, please use WB:RFI.
 * If you're an instructor and plan on using Wikibooks for a class project, see Guidelines for class projects
 * Please say hello at the Reading Room with any questions or ideas.
 * Eventually, you might want to read the Manual of Style and Policies and Guidelines.
 * Help us by participating in policy and guideline creation.
 * Please take a look at Naming policy before starting a new book.
 * Remember to maintain a Neutral point of view.
 * Explore, be bold in editing pages, and have fun!

You will find more resources in Community Portal. If you want to ask a question, visit the Study help desk, the Reading Room, IRC channel or ask me personally on my talk page. For site news, see the Bulletin board. It might be a good idea to add that page to your "watchlist" so that you can see when any new information is posted there. You can do that by clicking the tab labeled "watch" at the top of the page.

(This is not an automated message, I'll be watching during a time for any reply you make to it...)

Good luck! I was late but is now done :) --Panic (talk) 10:04, 1 February 2010 (UTC)

title: User talk:Sshibata


text:
User:Derbeth/Sandbox

 * Please stop uploading images without copyright information. You must have seen warning on the upload page:

we delete images with unknown status and may block notorious uploaders of such images. Please complete information about all of your images. If you have any questions, leave me a message. --~

 * Please stop uploading images with unknown copyright status. Such images are dangerous to Wikibooks,

because authors of copyrighted work may sue Wikibooks. Wikibooks does not accept any images you can find in the Internet. If you are adding public domain or GFDL images, insert copyright tag and link to source. If you are author of images you uploaded, mark them with PD-self or GFDL-self. If you continue ignoring warnings, you will be temporarily blocked from editing Wikibooks. If you have any questions, please leave me a message. --~

title: User:Derbeth/Sandbox


text:
User talk:RedEagle

Image:NIC.JPG
Could you add link to source of this image and other you marked as public domain? I know that if an image is public domain you don't have to do it, but it's better to know where the image come from (in case someone claims it's not public domain). --Derbeth talk 10:40, 28 November 2005 (UTC)

title: User talk:RedEagle


text:
User:Scoo

I'm mostly active at the English Wikipedia as en:Scoo.

title: User:Scoo


text:
Modern Physics/Table of nuclides

{split}

A table with the basic properties of all nuclides.

Legend

title: Modern Physics/Table of nuclides


text:
People's Tactics/Movement

To move a unit, the usual procedure is to click on the unit, then on the movement button, and finally on the destination hex. After clicking on the movement button, the hexes into which the unit may enter appear in a lighter color. At this point, if you move the pointer over a map hex, either the total movement cost or the “No movement possible” message appears in the message box. WARNING: there is no Undo button. This is by design and will not be changed. Be careful. Be very careful. Be extra careful. After you click on the destination hex, Murphy’s Law rears its ugly head and strikes.

Movement allowance and rate of expenditure
The maximum movement allowance for a given formation depends on the mix of Unit Type items:

 * SHQs have a fixed maximum allowance of 1 MPs.
 * Air formations and sea formations can move as far as the slowest Unit Type item in their TOE
 * THQs and land formations can move as far as their Movement Type allows them (see below)

MPs are expended at various rates, depending on the formation and the terrain:

 * Sea formations expend 1 MP per hex, and may only move in sea or port hexes (a port hex is a town on the coastline)
 * Air formations expend 1 MP per hex, but this happens in one of two ways: AIR WINGS are actually Air Bases, that can physically move from one (land) location to another, or attack another formation within their current Movement Allowance

THQs and LAND FORMATIONS:

 * Spend 1 MP per hex of Grass or Town
 * Spend 2 MPs per hex of Forest or Swamp
 * Spend 1 additional MP to cross a river, or to enter an enemy (or neutral) controlled hex
 * Spend 2 additional MPs to enter a Forest, if the formation’s movement type is Truck or Armour
 * May not enter Sea or Mountain hexes
 * May enter a Swamp hex if, and ONLY if, they do NOT have any Mobile, Artillery or Armour Unit Types in their composition
 * If there is a road linking two hexes AND the formation is already on one of those hexes, it can move at the expense of 1 MP regardless of the type of terrain (but not of the ownership: the 1 MP penalty for entering enemy/neutral territory still applies). This is the only way a unit may enter/stop/cross a Mountain hex
 * SHQs spend 1 MP per hex, and are only subject to the Sea, Mountain and enemy ownership limitations affecting THQs and land formations

Another constraint to movement, related to the ownership of a given hex: a player can only move into an hex owned by another player if they are at war with each other.

A final constraint to movement: no more than three units may be in the same hex. Units on board sea formations do not count for this limit.

Movement type
The THQ/LAND FORMATION’s movement type is related to the mix of Unit Items and the ratio of “Carrying capacity” to “Weight needing to be carried”. If there is only one class of Unit Type items in the mix, the movement type is the one associated with that class. The movement allowance of a formation is that of the slowest unit type that is not transported.

If there is enough carrying capacity to offset the combined Infantry and Artillery weight, the unit is Mobile, and has a movement allowance equal to the minimum movement allowance of the mobile or armour types. For example, a unit containing infantry, artillery and enough trucks so that carrying capacity is equal to or greater than the weight of the infantry and artillery, will move at the speed of the trucks (6 in the default rules). However, if a Royal Tank is added to this unit (which has a movement allowance of 4 in the default rules), the movement allowance of the land formation would be 4.

If there is enough carrying capacity to offset only Artillery weight and the unit contains infantry as well, the unit will have a movement allowance of the infantry unit type (3 for most unit types).

Airdrop and airlift movement
Land formations and THQs may be moved by air. For this to happen, three things are required: an air formation with sufficient movement allowance and carrying capacity (i.e., enough items of the Transporter Unit Type), the unit to be transported has to have at least 2 MPs still available, and both must be in the same hex.

Airlift differs from Airdrop in that: any unit may be Airlifted, but the destination must be a friendly town hex; only units with Airdrop capabilty may be Airdropped, but the destination may be any hex that the unit could normally enter (no Airdrops into the sea or mountains) and that the player doing the Airdrop may see (Fog of War and Shroud of Discovery restrictions). To conduct Airdrop/Airlift, click on the AIR WING, then on the Airdrop/Airlift button, then select the unit to transport (if more than one present; otherwise PT assumes it is the other one on the hex), then on the destination hex and, finally, confirm the movement by clicking on the large button “Do Airlift/Airdrop”.

Amphibious assault and sea transport
Land formations and THQs may also be moved by sea. For this to happen, three things are required: a sea formation with sufficient carrying capacity (i.e., enough items of the Cargoship or Light Carrier Unit Types); the unit to be transported has to have at least 1 MP still available; they have to be either in the same hex or in adjacent hexes.

Amphibious Assault is different from Sea Transport only in that the hex where a unit is disembarked is occupied by an enemy unit, and combat then occurs.

To conduct Sea Transport, click on the sea formation, then on the Load button, then on the unit to transport and finally on the large “Load unit” button). Move the sea formation for as many turns as desired. To disembark the unit, click on the “Unload” button, then on the destination hex and, finally, confirm the movement by clicking on the large button “Do Unload”.

One important difference between transport by air and transport by sea is that a unit may stay on board ships, while transport by air is always done in the same turn.

title: People's Tactics/Movement


text:
Data Coding Theory/Spectrum Spreading

Spread Spectrum
There are multiple ways in which multiple clients can share a single transmission medium. Time-Division Multiplexing (TDM) is the system where different clients get "time slices", periods of time where one client gets to transmit and other clients cannot. Since nobody else is transmitting, each client gets to use the entire spectrum, which means high bandwidth and a fast data rate. There is also Frequency-Division Multiplexing (FDM), where each client transmits at the same time, but on different frequencies. In FDM there is less available bandwidth, but each client gets to transmit for more time.

There is one more type that we need to discuss: Code-Division Multiplexing (CDM). CDM is also known as Spread-Spectrum multiplexing. In CDM, all clients can transmit at all times on all frequencies.

Other benefits to CDM, that we will discuss later, is it's use in encryption and the inability for another client to jam or interfere with a transmission.

Why CDM?
CDM, and the related CDMA, are technologies that were originally designed for use in the military. Many of the techniques described earlier in this book are designed to make optimal use of a transmission medium, in terms of higher bitrate while simultaneously minimizing the necessary bandwidth. CDM, however, takes the opposite approach of maximizing bandwidth in order to pursue other valuable qualities. CDM techniques specifically widen and flatten the transmitted signal, in some instances the signal becomes so wide and so short that it actually falls below the noise floor, and is impossible to discern. In addition, CDM signals rely on a special type of code called a PN code to decipher. These two qualities together mean that CDM transmissions are virtually immune to eavesdropping or interception.

Another benefit to CDM is that since the bandwidth being used is spread out, it is nearly impossible for another person to jam the transmission with interference. Also, since the transmission energy is spread out across a wide frequency range, the data signal can be indistinguishable from the background noise, which can prevent eavesdropping.

A third benefit, as if we need a third, is that CDM transmissions have the nearly magical property that we can simultaneously transmit multiple transmissions in the same time slice, and in the same frequency band, without ISI problems. This is how modern cellphone networks operate: multiple cell phones can talk at the same time in the same frequency band.

Direct CDM
Let's start out with an exercise. Let's say that we want to send some digital data, for instance 1011. What we will do is combine this data with another code, called the spreading code that is 3 times as long, and travelling 3 times as fast.

But wait a minute, if the spreading code is moving 3 times as fast (3 times the bit rate), then it will require 3 times the bandwidth to transmit! Well, this is correct. CDM requires more bandwidth to transmit a single signal than either TDM or FDM, but we will see in a minute why this doesn't matter to us.

Let's say that our spreading code is as follows: 101100111000. Now, we will combine our information signal (1011) with the spreading code as follows: We will logically XOR each digit of the information signal with 3 consecutive digits of the spreading code (because the spreading code is moving 3 times as fast. We will use the "X" symbol to denote the XOR operation:

1    0     1     1 X 101 X 100 X 111 X 000 - - - -  010   100   000   111

And now our resulting code is the value 010100000111. This will be called our transmission code. Now, we can pick one of our binary transmission methods(ASK, M-ary PSK, QAM, etc...) to transmit this resultant digital signal over the channel to the receiver.

To demultiplex a CDM signal, we make use of the following mathematical rule:

a X b X b = a

Remember, the "X" symbol here is the XOR operation. It would seem that if we XOR the transmission code with the spreading code, we will get back our original information signal! The only problem is that we need to have the same exact spreading code on the receiving end, to demultiplex the signal.

Benefits of CDM
So what exactly is the benefit of CDM? First, let's take a look at the spreading code:

Spreading Code
The spreading code is selected to have a number of different properties, but the most important is that the spreading code must be a pseudo-random number (PN). PN numbers look random, but since we must be able to generate the same signal on the receiving end, the spreading code can't be completely random. Because of this property, it can be very difficult for an eavesdropper to intercept our data, because other people do not necessarily know our spreading code. Even if other people did know our spreading code, they would not necessarily know what point in the code we were at. Some spreading codes can be very long.

Increased Bitrate
Our spreading code is being generated at a much higher bitrate than our data code is. According to Shannon's channel capacity, for the same SNR and a larger bit rate, our signal will be spread out over a much larger bandwidth.

Security
Now, since we know that the Spreading code looks like noise, it is safe to assume that when we XOR in our information signal, the result will look like noise as well. In fact, the transmitted signal looks so much like noise, that unless the receiver has a perfectly synchronized spreading code to use in demultiplexing, the signal is impossible to recover. This makes CDM relatively secure.

Multiplexing
Using CDM, we can transmit multiple signals simultaneously over exactly the same frequency band. This is important because TDM allows us to use the same frequency band but it separates out time slices. FDM doesn't need time slices, but it separates out signals into different frequency bands. CDM allows us to transmit signals at exactly the same time, in exactly the same frequency band.

Now, when we receive the multiplexed signals simultaneously, each receiver can XOR with the spreading code, to get back the original signal. Remember, each transmission signal looks like noise, so the receivers will simply ignore the signals that don't correlate with the spreading code. --Mangosrgr8 (discuss • contribs) 15:33, 4 December 2013 (UTC)I think this needs expanding; how does this (non)correlation occour? Why don't other signals (including 'real' noise) affect the transmission?

direct CDM (DSS)
Direct CDM, also called direct spread spectrum (DSS), multiplexes data using a trick with the digital XOR operation.

Examples of Direct CDM
Direct CDM techniques are used in Cellular phone transmissions in North America. This is because there are far too many cellphones to give each phone its own frequency range, or its own time slice. Using CDM, all the phones can simultaneously talk over the same frequency band at the same time.

Frequency Hopping CDM (FHSS)
Frequency Hopping CDM, also called frequency hopping spread spectrum (FHSS), transmits on only one narrow frequency band for a very short amount of time, then "hops" to some other frequency.

Let's say we have our PN generator, which is creating a spreading code in real time. We take a certain number of bits from that PN generator at a time, and use them to pick a frequency range. We then transmit a short burst of data on that range, and then hop to the next frequency range for the next burst of data.

If we have the same PN generator on the receiving end, we can then use that spreading code to pick which frequency bands to listen to at any given time. Using frequency hopping, our signal will take more bandwidth than normal (because we are using multiple bands to send information on. Frequency Hopping has several advantages including the fact that it allows us to make better use of more bandwidth simultaneously, and—if we hop fast enough—it provides some protection against reflections ("fading") and noise sources obliterating a few of the narrow bands.

Frequency hopping has the disadvantage the receiver cannot use PSK, QPSK, or M-ary PSK techniques, because it is just too hard to synchronize the different phase angles at different times on different frequency bands. However M-ary FSK is frequently used, with great success.

Fast and Slow Hops
A system is called a "Slow Hopping System" if the hop rate is slower than the symbol rate (an integer number of symbols transmitted per hop). A system is called a "Fast Hopping System" if the symbol rate is slower than the hop rate (an integer number of hops per each symbol). Fast hop systems are more complicated to implement, but are more immune to channel distortion.

COFDM
An orthogonal frequency division multiplexing (OFDM) system is similar to a frequency hopping system in that part of the information is transmitted at one narrowband frequency, and other information is transmitted at a different narrowband frequency. However, rather than transmitting at only one narrowband frequency at a time, an OFDM system transmits at all of its frequencies all the time. Because any one narrow band it transmitted constantly, it's fairly easy to synchronize phase angles and use the best modulation technique for that band (QPSK). Because all the frequencies are generated by one transmitter, it is possible to pack them far more tightly together without interference than a system that dedicated each frequency to a different transmitter.

Reflections ("fading") and noise sources often obliterate a few of the narrow bands. To overcome this, the bits are "coded" (COFDM). A forward error correction (Data Coding Theory/Forward Error Correction) code is spread across every channel, such that even if 2 channels are completely obliterated, only 2 bits of the code word are lost. Then the receiver uses the FEC to reconstruct the obliterated data.

In practice, practically all OFDM systems are coded orthogonal frequency division multiplexing (COFDM) systems.

title: Data Coding Theory/Spectrum Spreading


text:
Engineering Acoustics/Basic Room Acoustic Treatments

Introduction
Many people use one or two rooms in their living space as "theatrical" rooms where theater or music room activities commence. It is a common misconseption that adding speakers to the room will enhance the quality of the room acoustics. There are other simple things that can be done to increase the acoustics of the room to produce sound that is similar to "theater" sound. This site will take you through some simple background knowledge on acoustics and then explain some solutions that will help improve sound quality in a room.

Room Sound Combinations
The sound you hear in a room is a combination of direct sound and indirect sound. Direct sound will come directly from your speakers while the other sound you hear is reflected off of various objects in the room.

The Direct sound is coming right out of the TV to the listener, as you can see with the heavy black arrow. All of the other sound is reflected off surfaces before they reach the listener.

sound travels in the ground faster than in the air because the particles in the solid are closer so they vibrate faster and have a quicker reaction.

Good and Bad Reflected Sound
Have you ever listened to speakers outside? You might have noticed that the sound is thin and dull. This occurs because when sound is reflected, it is fuller and louder than it would if it were in an open space. So when sound is reflected, it can add a fullness, or spaciousness. The bad part of reflected sound occurs when the reflections amplify some notes, while cancelling out others, changing the character of the sound. It can also affect tonal quality and create an echo-like effect. There are three types of reflected sound, pure reflection, absorption, and diffusion. Each reflection type is important in creating a "theater" type acoustic room.

Reflected Sound
Reflected sound waves, good and bad, affect the sound you hear, where it comes from, and the quality of the sound when it gets to you. The bad news when it comes to reflected sound is standing waves. These waves are created when sound is reflected back and forth between any two parallel surfaces in your room, ceiling and floor or wall to wall. Standing waves can distort noises 300 Hz and down. These noises include the lower mid frequency and bass ranges. Standing waves tend to collect near the walls and in corners of a room, these collecting standing waves are called room resonance modes.

Finding your room resonance modes
First, specify room dimensions (length, width, and height). Then follow this example:

1. There are some room dimensions that produce the largest amount of standing waves.
a. Cube

b. Room with 2 out of the three dimensions equal

c. Rooms with dimensions that are multiples of each other

Absorbed
The sound that humans hear is actually a form of acoustic energy. Different materials absorb different amounts of this energy at different frequencies. When considering room acoustics, there should be a good mix of high frequency absorbing materials and low frequency absorbing materials. A table including information on how different common household surfaces absorb sound can be found on the website http://www.crutchfieldadvisor.com/learningcenter/home/speakers_roomacoustics.html?page=2#materials_table

Diffused Sound
Using devices that diffuse sound is a fairly new way of increasing acoustic performance in a room. It is a means to create sound that appears to be "live". They can replace echo-like reflections without absorbing too much sound.

Some ways of determining where diffusive items should be placed were found on http://www.crutchfieldadvisor.com/S-hpU9sw2hgbG/learningcenter/home/speakers_roomacoustics.html?page=4:

1.) If you have carpet or drapes already in your room, use diffusion to control side wall reflections.

2.) A bookcase filled with odd-sized books makes an effective diffusor.

3.) Use absorptive material on room surfaces between your listening position and your front speakers, and treat the back wall with diffusive material to re-distribute the reflections.

How to Find Overall Trouble Spots In a Room
Every surface in a room does not have to be treated in order to have good room acoustics. Here is a simple method of finding trouble spots in a room.

1.) Grab a friend to hold a mirror along the wall near a certain speaker at speaker height.

2.) The listener sits in a spot of normal viewing.

3.) The friend then moves slowly toward the listening position (stay along the wall).

4.) Mark each spot on the wall where the listener can see any of the room speakers in the mirror.

5.) Congratulations! These are the trouble spots in the room that need an absorptive material in place.  Don't forget that diffusive material can also be placed in those positions.

References Sound
http://www.ecoustics.com/Home/Accessories/Acoustic_Room_Treatments/Acoustic_Room_Treatment_Articles/

http://www.audioholics.com/techtips/roomacoustics/roomacoustictreatments.php

http://www.diynetwork.com/diy/hi_family_room/article/0,2037,DIY_13912_3471072,00.html

http://www.crutchfieldadvisor.com/S-hpU9sw2hgbG/learningcenter/home/speakers_roomacoustics.html?page=1

Back to the main page


text: User talk:168.169.120.79

title: User talk:168.169.120.79


text:
User:Ehusman~enwikibooks

I received an MSEE in 2000 and have 18 years of experience in engineering photography.

title: User:Ehusman~enwikibooks


text:
Talk:Veterinary Medicine/Domestication

Most people wrinkle their noses when I bring up the subject, but Rattus Norvegicus make much better pets than guiena pigs, hamsters or gerbils. In the early sixties, the high school biology teacher needed a volunteer to take a rat home over the holiday vacation. I had a female who delivered a litter of six pups. They were hairless, pink and 2-3cm long. It took ten days before their eyes developed sufficiently to open and they had fur. Not wanting to expose them to the elements, the teacher allowed me to keep them at home in cages. Handled frequently, they seemed to thrive on human attention. The only time any of them ever bit, was when a female was about to deliver a litter. I think this is rat talk for, "I want to be alone", meaning that it is probably best to put her into the O.B. cage with gloved hands. I do not know whether other adults would eat newborns, but I once had to isolate a mother and litter from other adult males who were trying to steal the pups' dinner.

I like rats as pets and would have some, but I doubt my cats would leave them alone.

J.D., Detroit, MI

title: Talk:Veterinary Medicine/Domestication


text:
Analog and Digital Conversion

This book will attempt to explore the field of data conversion between analog and digital representations. This book will also explore some inherent problems in representing analog signals with digital data and vice versa, as well showing some common schemes for generating, coding, and transmitting the sampled data. Readers of this book would benefit strongly from a prior knowledge of the following subjects:

 * Semiconductors
 * Circuit Theory
 * Digital Circuits

Once an analog signal is sampled, and represented in a digital domain, we can use techniques of Digital Signal Processing to manipulate the data. Those topics will not be covered in this book.

''This book is in a very early stage of development, and many of the pages here will be stubs, or simply outlines. In time, more information will be filled in, but we need help from contributors like you. Feel free to help out and contribute!''

Section 1: Conversion Basics

 * /Introduction/
 * /Analog vs Digital/
 * /Sampling and Reconstruction/

Section 2: Sampling and Quantizing

 * /The Ideal Sampler/
 * /Sampling Theorem/
 * /Nyquist Sampling Rate/
 * /Resolution and Bitrate/
 * /Signed and Unsigned Quantities/
 * /Spectral Effects/
 * /Interpolation/

Section 3: Data Representation

 * /Differential Pulse-Coded Modulation/ (DPCM)
 * /Delta Modulation/
 * /Continuously-Variable Slope Delta Modulation/ (CVSDM)

Section 4: Signal Reconstruction

 * /Hold Circuits/
 * /Other Reconstructors/
 * /Reconstruction Effects/

Section 5: Quantization, Errors, Noise

 * /Uniform Quantization/
 * /Non-Uniform Quantization/
 * /Fixed Wordlength Effects/
 * /Sources of Error/

Section 6: Building Converters

 * /ADC Converters/
 * /DAC Converters/

Section 7: Appendices

 * /Reference Materials/

title: Analog and Digital Conversion


text:
User:Whiteknight/Book Foundry

The Book Foundry is my planning area where I prepare outlines for new books, projects, and wikiversity courses.

Plans, Notes, and Outlines
{| style="width: 100%; background-color: transparent;"
 * style="vertical-align: top; width: 50%" |
 * style="vertical-align: top; width: 50%" |

Proposed Books

 * style="vertical-align: top;" |

Header Templates
These are templates for creating new custom page headers. Anybody is welcome to use these templates in any book. Each page contains it's own instructions, so click the "(View)" link to see the template and the instructions for use.

Other Templates
These are pre-made templates for a variety of purposes for use in a book. The instructions for each template are located on the page itself. Click "View" to see these instructions.

Do you have an idea for a new book, course, or project? Let me know about it, and I can probably help. Send me a message on my user talk page.
 * }

title: User:Whiteknight/Book Foundry


text:
LaTeX/Lengths

In TeX, a length is
 * a floating point number followed by a unit, optionally followed by a stretching value;

 * a floating point factor followed by a macro that expands to a length.

Units
First, we introduce the LaTeX measurement units. All LaTeX units are two-letter abbreviations. You can choose from a variety of units. Here are the most common ones.

The point is the default unit and 1pt is the default length. All other units are converted to the point by a fixed ratio.

Here are some less common units.

Box lengths
A box in TeX is characterized by three lengths:
 * depth
 * height
 * width

See Boxes.

Length manipulation
You can change the values of the variables defining the page layout with two commands. With this one you can set a new value for an existing length variable:

with this other one, you can add a value to the existing one:

You can create your own length with the command, and you must create a new length before you attempt to set it:

You may also set a length from the size of a text with one of these commands:

The calc package provides also the function

When using these commands, you may duplicate the text that you want to use as reference if you plan to also display it. But LaTeX also provides to avoid this duplication. You may wish to look at the example below to see how you can use these. See Boxes for more details.

You can also define stretched values. A stretching value is a length preceded by or  to specify to what extent tex is authorized to change the length. Example:

It means that tex will try to use a length of 10pt; if it is underfull, it will raise the length up to a maximum of 15pt; if it is overfull, it will lower the length up to a minimum of 7pt.

Note that it is not mandatory to specify both the and the  values, but if you do,  must be placed before.

To print a length, you can use the command:

Plain TeX
To create a new length:

To set a length:

To view, it is the same as with LaTeX, using the command.

LaTeX default lengths
Common length macros are:

 * \baselineskip : The normal vertical distance between lines in a paragraph.
 * \baselinestretch : A factor multiplying \baselineskip. Has to be set with
 * \columnsep : The distance between columns.
 * \columnwidth : The width of the column.
 * \evensidemargin : The margin for 'even' pages (think of a printed booklet).
 * \linewidth : The width of a line in the local environment.
 * \oddsidemargin : The margin for 'odd' pages (think of a printed booklet).
 * \paperwidth : The width of the page.
 * \paperheight : The height of the page.
 * \parindent : The normal paragraph indentation.
 * \parskip : The extra vertical space between paragraphs.
 * \tabcolsep : The default separation between columns in a tabular environment.
 * \textheight : The height of text on the page.
 * \textwidth : The width of the text on the page.
 * \topmargin : The size of the top margin.
 * \unitlength : Units of length in environment.

Fixed-length spaces
To insert a fixed-length space, use:

stands for horizontal space, for vertical space.

If such a space should be kept even if it falls at the end or the start of a line, use instead.

If the space should be preserved at the top or at the bottom of a page, use the starred version of the command,, instead of. If you want to add space at the beginning of the document, without anything else written before, then you may use

It's important you use the command instead of, otherwise LaTeX can silently ignore the extra space.

TeX features some macros for fixed-length spacing.
 * : Inserts a small space in vertical mode (between two paragraphs).
 * : Inserts a medium space in vertical mode (between two paragraphs).
 * : Inserts a big space in vertical mode (between two paragraphs).

The vertical mode is during the process of assembling boxes "vertically", like paragraphs to build a page. The horizontal mode is during the process of assembling boxes "horizontally", like letters to build a word or words to build a paragraph.

The fact they are vertical mode commands mean they will be ignored (or fail) in horizontal mode such as in the middle of a paragraph. The first token next to a double linebreak is still in vertical mode if it does not expand to characters.

Rubber/Stretching lengths
The command:

generates a special rubber space where is a number, possibly a float. It stretches until all the remaining space on a line is filled up. If two commands are issued on the same line, they grow according to the stretch factor.

The same way, you can stretch vertically:

You can also use instead of.

The command, in connection with, can be used to typeset text on the last line of a page, or to center text vertically on a page.

There are 'shortcut commands' for stretching with factor 1 (i.e. with or ):  and.

Example:

Fill the rest of the line
Several macros allow filling the rest of the line -- or stretching parts of the line -- in different manners.
 * will produce empty space.
 * will produce dots.
 * will produce a rule.

Examples
Resize an image to take exactly half the text width :

Make distance between items larger (inside an itemize environment) :

Use of to resize an image to the height of the text:

title: LaTeX/Lengths


text:
User:Whiteknight/Sig

User: (talk) (current)

title: User:Whiteknight/Sig


text:
Communication Networks/IP Protocol and ICMP

Internet Protocol
Internet Protocol (IP) is the Internet layer protocol that contains address information for routing packets in Network Layer of OSI model.

We've talked so far about TDM (Time-Division Multiplexing) techniques, and we've also talked about how different packets in a given network can contain address information, that will help the routers along the way move the data to its destination. This page will talk about one of the most important parts of the internet: the IP Protocol.

IP, as an integral part of TCP/IP, is for addressing and routing packets. It provides the mechanism to transport datagram across a large network. In more detail, the main purpose of IP is to handle all the functions related to routing and to provide a network interface to the upper-layer protocols, such as TCP from Transport Layer. Applications use this single protocol in the layer for anything that requires networking access.

What is IP?
The Internet Protocol is essentially what makes the Internet different from other digital networks (ARPANET, for instance). IP protocol assigns a unique address, called the "IP Address" to each computer in a network, and these IP addresses are used to route packets of information from a source to a destination. IP protocol calls for each device in the network to make the best effort possible to transmit the data, but IP doesn't guarantee that the data will arrive. If you are looking for a guarantee, you will have to implement a higher-level protocol (such as TCP).

From the OSI model, the IP Protocol is a Network-Layer Protocol.

The IP address is a different number from the "MAC Address" that is also found inside a computer. The IP address is a 32bit value that is unique among computers in a given local network. A MAC address is a larger number that is unique in the entire world. However, it is very difficult to route packets according to the MAC address.

IP also specifies the header that packets must have when traveling across the Internet. This header is called the IP header, and will be discussed in the next chapter.

The IP Protocol also specifies that each IP packet must have an error-checking code attached to the end of the packet. This error-checking code, called the "Cyclic Redundency Check" or CRC Checksum is capable of helping the receiving computer determine if the packet has had any bit errors during transmission. The CRC code is much more powerful at detecting errors than a single parity bit is, but CRC can be time consuming to calculate.

IP Address
IP address is a set of numbers identify any packet sends from sender to receiver on IP network in the Internet. It is a software address associated with interfaces, 32-bit information as a hierarchical address structures to handle a large number of addresses, assigns to each machine as interface that designs to communicate between hosts in different network. Dotted-decimal notation usually use as for easy understanding purpose.

An IP address consists of two parts, Network Address and Host Address. Network Address for identify each network, and Host Address for identify individual machine.

Example:

One would wonder what the IP address information of the current machine that connecting to the network, we could use ipconfig command to find out:

Figure 6 ipconfig Command for Address Information

The current machine turns out to have the IP address of 192.168.1.4. The next figure will show a physical interface representation corresponds to the IP address, and notice the first 16 bits are representing the network address, which will stay the same within its own network:

Figure 7 Network Connection

There are different classes of networks, based on the network size, as shown in the following:

Figure 8 IP Address Class Identification

Notice that bits in the beginning of each class set are defines by address schemes, which will not be used. So, the network address ranges for each class are as follows:

However, because of the address demanding and shortage, there IP addresses exist that reserved for special purposes and sets for private network.

IP Header
The IP header is a large field of information that is appended to the beginning of the packet. The IP header includes a large amount of information about the packet, including the source IP address, and the destination IP address. Also, the IP header (IPv6 and up) includes information about the local area networks for both the source and the destination terminals.

Each IP header contains information relates to data sends from upper layers for identifying the destination, and is shown as follows:

Figure 4: IP Packet

Here is a snapshot of an IP packet capture on Ethereal:

Figure 5: IP packet captured from Ethereal

Notice in the protocol field that captured above, it indicates TCP. Since the header does not have any protocol information for the next layer, it simply directs IP to pass the segment to TCP at the Transport Layer. All other fields correspond to the description above.

CRC Checksum
The CRC checksum is a 16bit data item appended to the end of an internet IP packet. The CRC contains a number that the receiver runs through a particular algorithm, and can then determine if the packet is correct, or if there is an error.

Modulo-2 Arithmetic
This section will be a short primer on Modulo-2 Arithmetic

Internet Control Message Protocol (ICMP)
Internet Control Message Protocol is used to pass information related to network operation between hosts, routers and gateways in network level.

There are four major functions as follows:
 * Announce network errors when the network being unreachable.
 * Announce network congestion when a router over-buffer due to too many packets transmitting.
 * Assist Troubleshooting when packets send over a network to compute the loss percentages and round-trip times.
 * Announce Timeouts when TTL of an IP packet drops to zero, where a packet being discards.

Please note that ICMP packets are crafted at the IP layer and thus does not guarantee delivery.

ICMP, the Internet Control Message Protocol is a counterpart to the IP Protocol that allows for control messages to be sent across the network.

Subnetwork
Subnetwork (Subnet) is used to group computers in the same network that has IP address with the same network address. Subnet is one of the solutions for resolving the shortage of addresses and to help utilizing the address assignment in the network. Subnet mask is introduced to have the network breaks into subnetworks in order to provide a hierarchical routing architecture.

Example:

Subnet: 180.28.30.1-128

Subnet mask: 255.255.255.128

Slash notation is introduced to identify the number of bits turn on. When the Internet Service Provider (ISP) allocates addresses to the users, these addresses will be in a slash notation form:

Example:

In addition to the advantage of grouping computer, there are some benefits from subnetwork:

 * Reduced network traffic
 * Increase network performance
 * Simplified management

Classless Interdomain Routing (CIDR), also known as supernetting, is another solution for shortage of addresses. The basic idea is the same as subnet. The only different is that host address is occupying bits from the network address, which help for address wasteful avoidant purpose.

Example:

Summary
Internet Protocol (IP) is responsible for addressing and routing packets in the Network Layer (layer 3) of the 7 layer OSI model. Messages are transmitted hop by hop in this layer, and each node's interface has a unique IP address for identification in the network. It allows datagram to transport across a large network.

Internet Control Message Protocol (ICMP) is a way to send error messages or perform network diagnostics across a network. Two of the most common tools utilizing ICMP are Traceroute and Ping.

Exercises
Question:
 * 1) What is the Class C private IP address space?
 * 2) What is the subnetwork number of a host with an IP address of 172.16.170.0/22?
 * 3) What is the subnetwork number of a host with an IP address of 192.168.111.88/26?
 * 4) The network address of 192.16.0.0/19 provides how many subnets and hosts?
 * 5) You have a Class B network ID and need about 450 IP addresses per subnet.  What is the best mask for this network?
 * 6) You router has the following IP address on Ethernet: 172.16.112.1/20.  How many hosts can be accommodated on the Ethernet segment?
 * 7) If a company calls for technical support regarding to its malfunction network, what are the four basic steps to perform a IP addressing troubleshooting?
 * 8) If an Ethernet port on a router were assigned an IP address of 172.16.112.1/25, what would be the valid subnet address of this host?
 * 9) (T/F) ICMP messages are encapsulated in IP datagrams.
 * 10) (T/F) Ping program uses “TTL” field to detect if a destination host is alive.

Answer:
 * 1) 192.168.0.0 – 192.168.255.255
 * 2) 172.16.168.0
 * 3) 192.168.111.64
 * 4) 8 subnets, 8190 hosts each
 * 5) 255.255.254.0
 * 6) 4094
 * 7) (a) Ping 127.0.0.1.  (b) Ping local host IP address.  (c) Ping default gateway.  (d) Ping the remote server.
 * 8) 172.16.112.0
 * 9) True
 * 10) False - Ping waits for an "echo response" packet from the target.


text: User talk:84.13.67.210

title: User talk:84.13.67.210


text:
Communication Networks/TCP and UDP Protocols

TCP and UDP
The TCP and UDP protocols are two different protocols that handle data communications between terminals in an IP network (the Internet). This page will talk about what TCP and UDP are, and what the differences are between them.

In the OSI model, TCP and UDP are "Transport Layer" Protocols. Where TCP is a connection oriented protocol and UDP is a connectionless protocol.


text:
People's Tactics/Scenario Editor/Engine Variable

Engine Variables (only touch if you really know what you are doing)

This is a list of all the engine variables available for change in the editor, in the order they appear. The variables are grouped into fifteen sections.

One

 * Grass Movement Cost for Land Unit
 * Forest Movement Cost for Land Unit
 * Urban Movement Cost for Land unit
 * Sea Movement Cost for Land unit
 * Swamp Movement Cost for Land unit
 * Mountain Movement Cost for Land unit
 * Extra MP for mobile unit in forest
 * Extra MP for land unit to cross river
 * Extra MP for entering enemy land
 * Sea Movement Cost for Sea Unit
 * Urban Movement Cost for Sea Unit
 * Air Movement Cost per Hex

Two

 * Supply MP cost for Grass
 * Supply MP cost for Forest
 * Supply MP cost for Urban
 * Supply MP cost for Sea
 * Supply MP cost for Swamp
 * Supply MP cost for Mountain
 * Supply MP cost for Road
 * Weight of Supply

Three

 * Minimal Soft Att value to occupy enemy land
 * Maximum Unit Size in Weight Pts
 * Supply cost for Level 1 Entrenchment
 * Supply cost for Level 2 Entrenchment
 * Supply cost for Level 3 Entrenchment
 * Attack modifier versus lvl 1 entrenchment
 * Attack modifier versus lvl 2 entrenchment
 * Attack modifier versus lvl 3 entrenchment

Four

 * Population Divider (POP/PD = Supply production)
 * Distance 0 from THQ ... Supply%
 * Distance 1 from THQ ... Supply%
 * Distance 2 from THQ ... Supply%
 * Distance 3 from THQ ... Supply%
 * Distance 4 from THQ ... Supply%
 * Distance >5 from THQ ... Supply%
 * Supply% if no supply through port but through shore
 * Supply generated for SHQ * this value = max supply stock
 * Always allowed supply stock for SHQ
 * Readiness Attrition if IN supply
 * Readiness Attrition if OUT of supply
 * Always readiness gain = XP / this value
 * Minimal Readiness allowed if OUT of supply
 * Minimal Readiness allowed if IN supply
 * Basic Readiness gain by supply
 * Bonus Readiness gain by XP / this Value
 * Automatic XP increase until this XP Value
 * Automatic XP increase
 * SHQ Range … min 10 or so … and max 50 (longer calcs with longer range)
 * Pop needed for 1 Political Point production
 * Recon Points needed to look 1 hex away. Succesive exp
 * Hex Dammage recup in %pts per round
 * Ammount of ProdPoints to destroy to get 1 Fame Point
 * /100 = extra readiness loss absolute for artillery per combat round

Five

 * Multiplier of supply if you set supply production
 * Unitdivider; Unit softatt+hardatt/etc.. /unitdivider = counter

Six

 * Readiness loss modifier% for unit that is interdicted
 * Readiness loss modifier% for unit that interdicts itself
 * XP gain modifier% for unit that is interdicted
 * XP gain modifier% for unit that interdicts itself
 * Read loss modifier for attacked unit in normal land battle
 * Read loss modifier for unit attacking itself in normal land battle
 * Xp gain modifier for attacked unit in normal land battle
 * Xp gain modifier for unit attacking itself in normal land battle
 * Read loss modifier for land unit attacked by artillery
 * Read loss modifier for artillery unit attacking land unit
 * XP gain modifier for land unit attacked by artillery
 * XP gain modifier for artillery unit attacking land unit

Seven

 * Sea unit attacked by interdict. Read loss mod%
 * Unit interdiciting sea unit. Read loss mod%
 * Sea unit attacked by interdict. Xp gain mod%
 * Unit interdicting sea unit. Xp gain mod%
 * Sea unit attacked in harbour by land unit. Read loss mod%
 * Land unit attacking sea unit in harbour. Read loss mod%
 * Sea unit attacked in harbour by land unit. Xp gain mod%
 * Land unit attacking sea unit in harbour. Xp gain mod%
 * Sea unit attacked by sea unit. Read loss mod%
 * Sea unit attacking sea unit. Read loss mod%
 * Sea unit attacked by sea unit. Xp gain mod%
 * Sea unit attacking sea unit. Xp gain mod%
 * Sea unit attacked by artillery attack. Read loss mod%
 * Unit artillery attacking Sea unit. Read loss mod%
 * Sea unit attacked by artillery attack. Xp gain mod%
 * Unit artillery attacking Sea unit. Xp gain mod%

Eight

 * Air unit interdicted on land. Read loss mod%
 * Interdicting unit attacking air on land. Read loss mod%
 * Air unit interdicted on land. Xp gain mod%
 * Interdicting unit attacking air on land. Xp gain mod%
 * Dogfighting attacked. Read loss%
 * Dogfighting attacker. Read loss%
 * Dogfighting attacked. Xp gain mod%
 * Dogfighting attacker. Xp gain mod%
 * Air unit attacked on land. Read loss mod%
 * Land unit attacking Air unit on land. Read loss mod%
 * Air unit attacked on land. Xp gain mod%
 * Land unit attacking Air unit on land. Xp gain mod%
 * Air unit attacked by artillery/AA. Read loss mod%
 * Unit artillery/AA attacking air unit. Read loss mod%
 * Air unit attacked by artillery/AA. Xp gain mod%
 * Unit artillery/AA attacking air unit. Xp gain mod%

Nine

 * Xp gain modifier if Xp 75-100
 * Xp gain modifier if Xp 101-150
 * Read loss modifier for units with readiness<30
 * Read loss modifier for units with readiness 30-60

Ten

 * Minimum pop for almost smallest town sprite
 * Minimum pop for small town sprite
 * Minimum pop for medium town sprite
 * Minimum pop for large town sprite
 * Minimum pop for largest town sprite

Eleven

 * Officer Skill Creation. d100 .. below this number skill= 8 or 9
 * Officer Skill Creation. d100 .. below this number skill= 7
 * Officer Skill Creation. d100 .. below this number skill= 6
 * Officer Skill Creation. d100 .. below this number skill= 5
 * Officer Skill Creation. d100 .. below this number skill= 4
 * Officer Skill Creation. d100 .. below this number skill= 3 or 2. Above = 1
 * Officer creation. Basic retreat%
 * Officer creation. + Random retreat % (retreat=basic+random)

Twelve

 * Air Wing interdicts within this many hexes range … min 1 … Max 2
 * AA guns participate from hex distance ... Min 0 … Max 5
 * Sub dive chance divider if attacked by aircraft
 * Softdef modifier for Grass
 * Softdef modifier for Forest
 * Softdef modifier for Urban
 * Softdef modifier for Sea
 * Softdef modifier for Swamp
 * Softdef modifier for Mountain
 * Softdef modifier for Swamp
 * HardAtt mod for Grass
 * HardAtt mod for Forest
 * HardAtt mod for Urban
 * HardAtt mod for Sea
 * HardAtt mod for Swamp
 * HardAtt mod for Mountain
 * Softdef modifier for defending against amphibious invasion/airdrop
 * HardAtt modifier if doing an amphibious invasion/airdrop
 * Number of combat rounds
 * Minimal cost in MP for battle
 * Max MP unit may have left after battle
 * Attack modifier for attack over River
 * 100 + % attack modifier for each extra multipronged attack
 * Frontsize limitator in # of unittype frontsize points
 * Readiness modifier% if Attacking unit breaks off attack
 * Readiness modifier is defending unit flees
 * Readiness modifier per combat round a def.unit cannot flee
 * Disruption for new commander
 * Disruption for making new unit
 * Disruption caused by retreat
 * Disruption caused by attack breakoff

Thirteen

 * Transfer cost divider for over land transport
 * Transfer cost divider for over sea transport
 * Transfer cost divider for land transport after sea transport
 * Cost for new Land Unit
 * Cost for new Sea unit
 * Cost for new Air unit
 * Cost for new THQ
 * Cost for new SHQ
 * HQ TYPE COUNT .. howmany different types can be in shq

Fourteen

 * Lose mobile loss divider for attacker if offensive fails
 * Lose artillery loss divider for attacker if offensive fails
 * Minimum readiness needed to intercept enemy aircraft

Fifteen

 * AI Forbidden. If = 1 then AI is forbidden to play in this scenario
 * / 100 = the XP/Readiness value of production points with loss.calc
 * neutral hex= 0 means neutral hex join auto and 1 means they dont
 * Campaign? 0=no, 1=yes
 * Campaign: Fog of Exploration?
 * Campaign: Block if loaded by user 1=yes, 0=no
 * Experience & Rdn modifier. higher is less xp/rdn drain, lower is more