text:
\section{Copyright}
All papers submitted for publication by AAAI Press must be accompanied by a valid signed copyright form or, in the case of technical reports, by a valid signed permission to distribute form. There are no exceptions to this requirement. You must send us the original version of this form. However, to meet the deadline, you may fax (1-650-321-4457) or scan and e-mail the form (pubforms14@aaai.org) to AAAI by the submission deadline, and then mail the original via postal mail to the AAAI office. \textbf{If you fail to send in a signed copyright or permission form, your paper will not be published.} You will find PDF versions of the AAAI copyright and permission to distribute forms in the author kit.

\section{Formatting Requirements in Brief}
We need source and PDF files that can be used in a variety of ways and can be output on a variety of devices. AAAI imposes some requirements on your source and PDF files that must be followed. Most of these requirements are based on our efforts to standardize conference manuscript properties and layout. These requirements are as follows, and all papers submitted to AAAI for publication must comply:

\begin{itemize}
\item Your .tex file must compile in PDF\LaTeX{} --- \textbf{ no .ps or .eps figure files.}
\item All fonts must be embedded in the PDF file --- \textbf{ this includes your figures.}
\item Modifications to the style sheet (or your document) in an effort to avoid extra page charges are NOT allowed.
\item No type 3 fonts may be used (even in illustrations).
\item Your title must follow US capitalization rules.
\item \LaTeX{} documents must use the Times or Nimbus font package (do not use Computer Modern for the text of your paper).
\item No \LaTeX{} 209 documents may be used or submitted.
\item Fonts that require non-English language support (CID and Identity-H) must be converted to outlines or removed from the document (even if they are in a graphics file embedded in the document).
\item Two-column format in AAAI style is required for all papers.
\item The paper size for final submission must be US letter. No exceptions.
\item The source file must exactly match the PDF.
\item The document margins must be as specified in the formatting instructions.
\item The number of pages and the file size must be as specified for your event.
\item No document may be password protected.
\item Neither the PDFs nor the source may contain any embedded links or bookmarks.
\item Your source and PDF must not have any page numbers, footers, or headers.
\item Your PDF must be compatible with Acrobat 5 or higher.
\item Your \LaTeX{} source file (excluding references) must consist of a \textbf{single} file (use of the ``input" command is not allowed.
\item Your graphics must be sized appropriately outside of \LaTeX{} (do not use the ``clip" command) .
\end{itemize}

If you do not follow the above requirements, it is likely that we will be unable to publish your paper.

\section{What Files to Submit}
You must submit the following items to ensure that your paper is published:
\begin{itemize}
\item A fully-compliant PDF file.
\item Your  \LaTeX{}  source file submitted as a \textbf{single} .tex file (do not use the ``input" command to include sections of your paper --- every section must be in the single source file). The only exception is the bibliography, which you may include separately. Your source must compile on our system, which includes the standard \LaTeX{} support files.
\item All your graphics files.
\item The \LaTeX{}-generated files (e.g. .aux and .bib file, etc.) for your compiled source.
\item All the nonstandard style files (ones not commonly found in standard \LaTeX{} installations) used in your document (including, for example, old algorithm style files). If in doubt, include it.
\end{itemize}

Your \LaTeX{} source will be reviewed and recompiled on our system (if it does not compile, you may incur late fees).   \textbf{Do not submit your source in multiple text files.} Your single \LaTeX{} source file must include all your text, your bibliography (formatted using aaai.bst), and any custom macros. Accompanying this source file, you must also supply any nonstandard (or older) referenced style files and all your referenced graphics files.

Your files should work without any supporting files (other than the program itself) on any computer with a standard \LaTeX{} distribution. Place your PDF and source files in a single tar, zipped, gzipped, stuffed, or compressed archive. Name your source file with your last (family) name.

\textbf{Do not send files that are not actually used in the paper.} We don't want you to send us any files not needed for compiling your paper, including, for example, this instructions file, unused graphics files, and so forth.  A shell script (created by an AAAI member --- it might not work without modification on your system) that might help you create the \LaTeX{} source package is included in the Author Kit.

\section{Using \LaTeX{} to Format Your Paper}

The latest version of the AAAI style file is available on AAAI's website. Download this file and place it in a file named ``aaai.sty" in the \TeX\ search path. Placing it in the same directory as the paper should also work. You must download the latest version of the complete author kit so that you will have the latest instruction set.

\subsection{Document Preamble}

In the \LaTeX{} source for your paper, you \textbf{must} place the following lines as shown in the example in this subsection. This command set-up is for three authors. Add or subtract author and address lines as necessary, and uncomment the portions that apply to you. In most instances, this is all you need to do to format your paper in the Times font. The helvet package will cause Helvetica to be used for sans serif, and the courier package will cause Courier to be used for the typewriter font. These files are part of the PSNFSS2e package, which is freely available from many Internet sites (and is often part of a standard installation).

Leave the setcounter for section number depth commented out and set at 0 unless you want to add section numbers to your paper. If you do add section numbers, you must uncomment this line and change the number to 1 (for section numbers), or 2 (for section and subsection numbers). The style file will not work properly with numbering of subsubsections, so do not use a number higher than 2.

\begin{quote}
\begin{small}
\textbackslash documentclass[letterpaper]{article}\\
\% \textit{Required Packages}\\
\textbackslash usepackage\{aaai\}\\
\textbackslash usepackage\{times\}\\
\textbackslash usepackage\{helvet\}\\
\textbackslash usepackage\{courier\}\\
\textbackslash setlength\{\textbackslash pdfpagewidth\}\{8.5in\}
\textbackslash setlength\{\textbackslash pdfpageheight\}\{11in\}\\
\%\%\%\%\%\%\%\%\%\%\\
\% \textit{PDFINFO for PDF\LaTeX{}}\\
\% Uncomment and complete the following for metadata (your paper must compile with PDF\LaTeX{})\\
\textbackslash pdfinfo\{\\
/Title (Input Your Paper Title Here)\\
/Author (John Doe, Jane Doe)\\
/Keywords (Input your paper's keywords in this optional area)\\
\}\\
\%\%\%\%\%\%\%\%\%\%\\
\% \textit{Section Numbers}\\
\% Uncomment if you want to use section numbers\\
\% and change the 0 to a 1 or 2\\
\% \textbackslash setcounter\{secnumdepth\}\{0\}\\
\%\%\%\%\%\%\%\%\%\%\\
\% \textit{Title, Author, and Address Information}\\
\textbackslash title\{Title\}\\
\textbackslash author\{Author 1 \textbackslash and Author 2\textbackslash\textbackslash \\
Address line\textbackslash\textbackslash\\ Address line\textbackslash\textbackslash \\
\textbackslash And\\
Author 3\textbackslash\textbackslash\\ Address line\textbackslash\textbackslash\\ Address line\}\\
\%\%\%\%\%\%\%\%\%\%\\
\% \textit{Body of Paper Begins}\\
\textbackslash begin\{document\}\\
\textbackslash maketitle\\
...\\
\%\%\%\%\%\%\%\%\%\%\\
\% \textit{References and End of Paper}\\
\textbackslash bibliography\{Bibliography-File\}\\
\textbackslash bibliographystyle\{aaai\}\\
\textbackslash end\{document\}
\end{small}
\end{quote}

\subsection{Inserting Document Metadata with \LaTeX{}}
PDF files contain document summary information that enables us to create an Acrobat index (pdx) file, and also allows search engines to locate and present your paper more accurately. \textbf{Document Metadata  for Author and Title are REQUIRED.}

If your paper includes illustrations that are not compatible with PDF\TeX{} (such as .eps or .ps documents), you will need to convert them. The epstopdf package will usually work for eps files. You will need to convert your ps files to PDF however.

\textit{Important:} Do not include \textit{any} \LaTeX{} code or nonascii characters (including accented characters) in the metadata. The data in the metadata must be completely plain ascii. It may not include slashes, accents, linebreaks, unicode, or any \LaTeX{} commands. Type the title exactly as it appears on the paper (minus all formatting). Input the author names in the order in which they appear on the paper (minus all accents), separating each author by a comma. You may also include keywords in the Keywords field.

\subsection{Preparing Your Paper}

After the preamble above, you should prepare your paper as follows:

\begin{quote}
\begin{small}
\textbackslash begin\{document\}\\
\textbackslash maketitle\\
...\\
\textbackslash bibliography\{Bibliography-File\}\\
\textbackslash bibliographystyle\{aaai\}\\
\textbackslash end\{document\}\\
\end{small}
\end{quote}
\subsection{Incompatible Packages}
The following packages are incompatible with aaai.sty and/or aaai.bst and must not be used (this list is not exhaustive --- there are others as well):
\begin{itemize}
\item hyperref
\item natbib
\item geometry
\item titlesec
\item layout
\item caption
\item titlesec
\item T1 fontenc package (install the CM super fonts package instead)
\end{itemize}

\subsection{Illegal Commands}
The following commands may not be used in your paper:
\begin{itemize}
\item \textbackslash input
\item \textbackslash vspace (when used before or after a section or subsection)
\item \textbackslash addtolength
\item \textbackslash columnsep
\item \textbackslash top margin (or text height or addsidemargin or even side margin)
\end{itemize}

\subsection{Paper Size, Margins, and Column Width}
Papers must be formatted to print in two-column format on 8.5 x 11 inch US letter-sized paper. The margins must be exactly as follows:
\begin{itemize}
\item Top margin: .75 inches
\item Left margin: .75 inches
\item Right margin: .75 inches
\item Bottom margin: 1.25 inches
\end{itemize}

The default paper size in most installations of \LaTeX{} is A4. However, because we require that your electronic paper be formatted in US letter size, you will need to alter the default for this paper to US letter size. Assuming you are using the 2e version of \LaTeX{}, you can do this by including the [letterpaper] option at the beginning of your file:
\textbackslash documentclass[letterpaper]{article}.

This command is usually sufficient to change the format. Sometimes, however, it may not work. Use PDF\LaTeX{} and include
\textbackslash setlength\{\textbackslash pdfpagewidth\}\{8.5in\}
\textbackslash setlength\{\textbackslash pdfpageheight\}\{11in\}
in your preamble.

\textbf{Do not use the Geometry package to alter the page size.} Use of this style file alters aaai.sty and will result in your paper being rejected.

\subsubsection{Column Width and Margins.}
To ensure maximum readability, your paper must include two columns. Each column should be 3.3 inches wide (slightly more than 3.25 inches), with a .375 inch (.952 cm) gutter of white space between the two columns. The aaai.sty file will automatically create these columns for you.

\subsection{Overlength Papers}
If your paper is too long, turn on \textbackslash frenchspacing, which will reduce the space after periods. Next,  shrink the size of your graphics. Use \textbackslash centering instead of \textbackslash begin\{center\} in your figure environment. If these two methods don't work, you may minimally use the following. For floats (tables and figures), you may minimally reduce \textbackslash floatsep, \textbackslash textfloatsep, \textbackslash abovecaptionskip, and \textbackslash belowcaptionskip. For mathematical environments, you may minimally reduce \textbackslash abovedisplayskip, \textbackslash belowdisplayskip, and \textbackslash arraycolsep. You may also alter the size of your bibliography by inserting \textbackslash fontsize\{9.5pt\}\{10.5pt\} \textbackslash selectfont
right before the bibliography.

Commands that alter page layout are forbidden. These include \textbackslash columnsep, \textbackslash topmargin, \textbackslash topskip, \textbackslash textheight, \textbackslash textwidth, \textbackslash oddsidemargin, and \textbackslash evensizemargin (this list is not exhaustive). If you alter page layout, you will be required to pay the page fee \textit{plus} a reformatting fee. Other commands that are questionable and may cause your paper to be rejected include  \textbackslash parindent, and \textbackslash parskip. Commands that alter the space between sections are also questionable. The title sec package is not allowed. Regardless of the above, if your paper is obviously ``squeezed" it is not going to to be accepted. Before using every trick you know to make your paper a certain length, try reducing the size of your graphics or cutting text instead or (if allowed) paying the extra page charge. It will be cheaper in the long run.

\subsection{Figures}
Your paper must compile in PDF\LaTeX{}. Consequently, all your figures must be .jpg, .png, or .pdf. You may not use the .gif (the resolution is too low), .ps, or .eps file format for your figures.

When you include your figures, you must crop them \textbf{outside} of \LaTeX{}. The command \textbackslash includegraphics*[clip=true, viewport 0 0 10 10]{...} might result in a PDF that looks great, but the image is \textbf{not really cropped.} The full image can reappear when page numbers are applied or color space is standardized.

\subsection{Type Font and Size}
Your paper must be formatted in Times Roman or Nimbus. We will not accept papers formatted using Computer Modern or Palatino or some other font as the text or heading typeface. Sans serif, when used, should be Courier. Use Symbol or Lucida or Computer Modern for \textit{mathematics only. }

Do not use type 3 fonts for any portion of your paper, including graphics. Type 3 bitmapped fonts are designed for fixed resolution printers. Most print at 300 dpi even if the printer resolution is 1200 dpi or higher. They also often cause high resolution imagesetter devices and our PDF indexing software to crash. Consequently, AAAI will not accept electronic files containing obsolete type 3 fonts. Files containing those fonts (even in graphics) will be rejected.

Fortunately, there are effective workarounds that will prevent your file from embedding type 3 bitmapped fonts. The easiest workaround is to use the required times, helvet, and courier packages with \LaTeX{}2e. (Note that papers formatted in this way will still use Computer Modern for the mathematics. To make the math look good, you'll either have to use Symbol or Lucida, or you will need to install type 1 Computer Modern fonts --- for more on these fonts, see the section ``Obtaining Type 1 Computer Modern.")

If you are unsure if your paper contains type 3 fonts, view the PDF in Acrobat Reader. The Properties/Fonts window will display the font name, font type, and encoding properties of all the fonts in the document. If you are unsure if your graphics contain type 3 fonts (and they are PostScript or encapsulated PostScript documents), create PDF versions of them, and consult the properties window in Acrobat Reader.

The default size for your type should be ten-point with twelve-point leading (line spacing). Start all pages (except the first) directly under the top margin. (See the next section for instructions on formatting the title page.) Indent ten points when beginning a new paragraph, unless the paragraph begins directly below a heading or subheading.

\subsubsection{Obtaining Type 1 Computer Modern for \LaTeX{}.}

If you use Computer Modern for the mathematics in your paper (you cannot use it for the text) you may need to download type 1 Computer fonts. They are available without charge from the American Mathematical Society:
http://www.ams.org/tex/type1-fonts.html.

\subsection{Title and Authors}
Your title must appear in mixed case (nouns, pronouns, and verbs are capitalized) near the top of the first page, centered over both columns in sixteen-point bold type (twenty-four point leading). This style is called ``mixed case." Author's names should appear below the title of the paper, centered in twelve-point type (with fifteen point leading), along with affiliation(s) and complete address(es) (including electronic mail address if available) in nine-point roman type (the twelve point leading). (If the title is long, or you have many authors, you may reduce the specified point sizes by up to two points.) You should begin the two-column format when you come to the abstract.

\subsubsection{Formatting Author Information}
Author information can be set in a number of different styles, depending on the number of authors and the number of affiliations you need to display. For several authors from the same institution, use \textbackslash and:

\begin{quote}
\begin{small}
\textbackslash author\{Author 1 \textbackslash and  ...  \textbackslash and Author \textit{n}\textbackslash \textbackslash  \\
Address line \textbackslash \textbackslash ~... \textbackslash \textbackslash ~Address line\}
\end{small}
\end{quote}

\noindent If the names do not fit well on one line use:

\begin{quote}
\begin{small}
\textbackslash author\{Author 1\}\textbackslash \textbackslash \\ \{\textbackslash bf Author 2\}\textbackslash \textbackslash ~
... \textbackslash \textbackslash ~\{\textbackslash bf Author \textit{n}\}\textbackslash \textbackslash \\
Address line \textbackslash \textbackslash ~ ... \textbackslash \textbackslash ~ Address line\}
\end{small}
\end{quote}

\noindent For authors from different institutions, use \textbackslash And:

\begin{quote}
\begin{small}
\textbackslash author\{Author 1\textbackslash \textbackslash ~ Address line \textbackslash \textbackslash ~...  \textbackslash \textbackslash ~ Address line
\textbackslash And  ...
\textbackslash And
Author \textit{n}\textbackslash \textbackslash \\ Address line\textbackslash \textbackslash ~
... \textbackslash \textbackslash ~
Address line\}
\end{small}
\end{quote}

\noindent To start a separate ``row" of authors, use \textbackslash AND:
\begin{quote}
\begin{small}
\textbackslash author\{Author 1\textbackslash\textbackslash ~ Address line \textbackslash\textbackslash ~
...  \textbackslash \textbackslash ~ Address line\textbackslash\textbackslash \\
\textbackslash AND\\
Author 2 \textbackslash\textbackslash ~ Address line \textbackslash\textbackslash ~
...  \textbackslash \textbackslash ~ Address line\textbackslash\textbackslash \\
\textbackslash And\\
Author 3 \textbackslash\textbackslash ~ Address line \textbackslash\textbackslash ~
...  \textbackslash \textbackslash ~ Address line\textbackslash\textbackslash \\\}
\end{small}
\end{quote}

\noindent If the title and author information does not fit in the area allocated, place
\textbackslash setlength\textbackslash titlebox\{\textit{height}\}
after the \textbackslash documentclass line where \{\textit{height}\} is something like 2.5in.

\subsection{\LaTeX{} Copyright Notice}
The copyright notice automatically appears if you use aaai.sty. If you are creating a technical report, it is not necessary to include this notice. You may disable the copyright line using the \verb+\+nocopyrightcommand. To change the entire text of the copyright slug, use:
\textbackslash copyrighttext \{\emph{text}\}.
Either of these must appear before \textbackslash maketitle. Please be advised, however, that \textit{if you disable or change the copyright line and transfer of copyright is required, your paper will not be published.}

\subsection{Credits}
Any credits to a sponsoring agency should appear in the acknowledgments section, unless the agency requires different placement. If it is necessary to include this information on the front page, use
\textbackslash thanks in either the \textbackslash author or \textbackslash title commands.
For example:
\begin{quote}
\begin{small}
\textbackslash title\{Very Important Results in AI\textbackslash thanks\{This work is
 supported by everybody.\}\}
\end{small}
\end{quote}
Multiple \textbackslash thanks commands can be given. Each will result in a separate footnote indication in the author or title with the corresponding text at the botton of the first column of the document. Note that the \textbackslash thanks command is fragile. You will need to use \textbackslash protect.

Please do not include \textbackslash pubnote commands in your document.

\subsection{Abstract}
The abstract must be placed at the beginning of the first column, indented ten points from the left and right margins. The title ÒAbstractÓ should appear in ten-point bold type, centered above the body of the abstract. The abstract should be set in nine-point type with ten-point leading. This concise, one-paragraph summary should describe the general thesis and conclusion of your paper. A reader should be able to learn the purpose of the paper and the reason for its importance from the abstract. The abstract should be no more than two hundred words in length. (Authors who are submitting short one- or two-page extended extracts should provide a short abstract of only a sentence or so.) \textbf{Do not include references in your abstract!}

\subsection{Page Numbers}

Do not \textbf{ever} print any page numbers on your paper.

\subsection{Text }
The main body of the paper must be formatted in ten-point with twelve-point leading (line spacing).

\subsection{Citations}
Citations within the text should include the author's last name and year, for example (Newell 1980). Append lower-case letters to the year in cases of ambiguity. Multiple authors should be treated as follows: (Feigenbaum and Engelmore 1988) or (Ford, Hayes, and Glymour 1992). In the case of four or more authors, list only the first author, followed by et al. (Ford et al. 1997).

\subsection{Extracts}
Long quotations and extracts should be indented ten points from the left and right margins.

\begin{quote}
This is an example of an extract or quotation. Note the indent on both sides. Quotation marks are not necessary if you offset the text in a block like this, and properly identify and cite the quotation in the text.

\end{quote}

\subsection{Footnotes}
Avoid footnotes as much as possible; they interrupt the reading of the text. When essential, they should be consecutively numbered throughout with superscript Arabic numbers. Footnotes should appear at the bottom of the page, separated from the text by a blank line space and a thin, half-point rule.

\subsection{Headings and Sections}
When necessary, headings should be used to separate major sections of your paper. Remember, you are writing a short paper, not a lengthy book! An overabundance of headings will tend to make your paper look more like an outline than a paper.

First-level heads should be twelve-point Times Roman bold type, mixed case (initial capitals followed by lower case on all words except articles, conjunctions, and prepositions, which should appear entirely in lower case), with fifteen-point leading, centered, with one blank line preceding them and three additional points of leading following them. Second-level headings should be eleven-point Times Roman bold type, mixed case, with thirteen-point leading, flush left, with one blank line preceding them and three additional points of leading following them. Do not skip a line between paragraphs. Third-level headings should be run in with the text, ten-point Times Roman bold type, mixed case, with twelve-point leading, flush left, with six points of additional space preceding them and no additional points of leading following them.

\subsubsection{Section Numbers}
The use of section numbers in AAAI Press papers is optional. To use section numbers in \LaTeX{}, uncomment the setcounter line in your document preamble and change the 0 to a 1 or 2. Section numbers should not be used in short poster papers.

\subsubsection{Section Headings.}
Sections should be arranged and headed as follows:

\subsubsection{Acknowledgments.}
The acknowledgments section, if included, appears after the main body of text and is headed ``Acknowledgments." This section includes acknowledgments of help from associates and colleagues, credits to sponsoring agencies, financial support, and permission to publish. Please acknowledge other contributors, grant support, and so forth, in this section. Do not put acknowledgments in a footnote on the first page. If your grant agency requires acknowledgment of the grant on page 1, limit the footnote to the required statement, and put the remaining acknowledgments at the back. Please try to limit acknowledgments to no more than three sentences.

\subsubsection{Appendices.}
Any appendices follow the acknowledgments, if included, or after the main body of text if no acknowledgments appear.

\subsubsection{References}
The references section should be labeled ``References" and should appear at the very end of the paper (don't end the paper with references, and then put a figure by itself on the last page). A sample list of references is given later on in these instructions. Please use a consistent format for references. Poorly prepared or sloppy references reflect badly on the quality of your paper and your research. Please prepare complete and accurate citations.

\subsection{Illustrations and Figures}
Figures, drawings, tables, and photographs should be placed throughout the paper near the place where they are first discussed. Do not group them together at the end of the paper. If placed at the top or bottom of the paper, illustrations may run across both columns. Figures must not invade the top, bottom, or side margin areas. Figures must be inserted using the \textbackslash usepackage\{graphicx\}. Number figures sequentially, for example, figure 1, and so on.

The illustration number and caption should appear under the illustration. Labels, and other text in illustrations must be at least nine-point type.

\subsubsection{Low-Resolution Bitmaps.}
You may not use low-resolution (such as 72 dpi) screen-dumps and GIF files---these files contain so few pixels that they are always blurry, and illegible when printed. If they are color, they will become an indecipherable mess when converted to black and white. This is always the case with gif files, which should never be used. The resolution of screen dumps can be increased by reducing the print size of the original file while retaining the same number of pixels. You can also enlarge files by manipulating them in software such as PhotoShop. Your figures should be a minimum of 266 dpi when incorporated into your document.

\subsubsection{\LaTeX{} Overflow.}
\LaTeX{} users please beware: \LaTeX{} will sometimes put portions of the figure or table or an equation in the margin. If this happens, you need to scale the figure or table down, or reformat the equation. Check your log file! You must fix any overflow into the margin (that means no overfull boxes in \LaTeX{}). If you don't, the overflow text will simply be eliminated. \textbf{Nothing is permitted to intrude into the margins.}

\subsubsection{Using Color.}
Your paper will be printed in black and white and grayscale. Consequently, because conversion to grayscale can cause undesirable effects (red changes to black, yellow can disappear, and so forth), we strongly suggest you avoid placing color figures in your document. Of course, any reference to color will be indecipherable to your reader.

\subsubsection{Drawings.}
We suggest you use computer drawing software (such as Adobe Illustrator or, (if unavoidable), the drawing tools in Microsoft Word) to create your illustrations. Do not use Microsoft Publisher. These illustrations will look best if all line widths are uniform (half- to two-point in size), and you do not create labels over shaded areas. Shading should be 133 lines per inch if possible. Use Times Roman or Helvetica for all figure call-outs. \textbf{Do not use hairline width lines} --- be sure that the stroke width of all lines is at least .5 pt. Zero point lines will print on a laser printer, but will completely disappear on the high-resolution devices used by our printers.

\subsubsection{Photographs and Images.}
Photographs and other images should be in grayscale (color photographs will not reproduce well; for example, red tones will reproduce as black, yellow may turn to white, and so forth) and set to a minimum of 266 dpi. Do not prescreen images.

\subsubsection{Resizing Graphics.}
Resize your graphics \textbf{before} you include them with LaTeX. You may \textbf{not} use trim or clip options as part of your \textbackslash includgraphics command. Resize the media box of your PDF using a graphics program instead.

\subsubsection{Fonts in Your Illustrations}
You must embed all fonts in your graphics before including them in your LaTeX document.

\subsection{References}
The aaai.sty file includes a set of definitions for use in formatting references with BibTeX. These definitions make the bibliography style fairly close to the one specified below. To use these definitions, you also need the BibTeX style file ``aaai.bst," available in the author kit on the AAAI web site. Then, at the end of your paper but before \textbackslash end{document}, you need to put the following lines:

\begin{quote}
\begin{small}
\textbackslash bibliographystyle\{aaai\}
\textbackslash bibliography\{bibfile1,bibfile2,...\}
\end{small}
\end{quote}

The list of files in the \textbackslash  bibliography command should be the names of your BibTeX source files (that is, the .bib files referenced in your paper).

The following commands are available for your use in citing references:
\begin{quote}
\begin{small}
\textbackslash cite: Cites the given reference(s) with a full citation. This appears as ``(Author Year)'' for one reference, or ``(Author Year; Author Year)'' for multiple references.\\
\textbackslash shortcite: Cites the given reference(s) with just the year. This appears as ``(Year)'' for one reference, or ``(Year; Year)'' for multiple references.\\
\textbackslash citeauthor: Cites the given reference(s) with just the author name(s) and no parentheses.\\
\textbackslash citeyear: Cites the given reference(s) with just the date(s) and no parentheses.
\end{small}
\end{quote}

\textbf{Warning:} The aaai.sty file is incompatible with the hyperref and natbib packages. If you use either, your references will be garbled.

Formatted bibliographies should look like the following examples.

\smallskip \noindent \textit{Book with Multiple Authors}\\
Engelmore, R., and Morgan, A. eds. 1986. \textit{Blackboard Systems.} Reading, Mass.: Addison-Wesley.

\smallskip \noindent \textit{Journal Article}\\
Robinson, A. L. 1980a. New Ways to Make Microcircuits Smaller. \textit{Science} 208: 1019--1026.

\smallskip \noindent \textit{Magazine Article}\\
Hasling, D. W.; Clancey, W. J.; and Rennels, G. R. 1983. Strategic Explanations in Consultation. \textit{The International Journal of Man-Machine Studies} 20(1): 3--19.

\smallskip \noindent \textit{Proceedings Paper Published by a Society}\\
Clancey, W. J. 1983b. Communication, Simulation, and Intelligent Agents: Implications of Personal Intelligent Machines for Medical Education. In Proceedings of the Eighth International Joint Conference on Artificial Intelligence, 556--560. Menlo Park, Calif.: International Joint Conferences on Artificial Intelligence, Inc.

\smallskip \noindent \textit{Proceedings Paper Published by a Press or Publisher}\\
Clancey, W. J. 1984. Classification Problem Solving. In \textit{Proceedings of the Fourth National Conference on Artificial Intelligence,} 49--54. Menlo Park, Calif.: AAAI Press.

\smallskip \noindent \textit{University Technical Report}\\
Rice, J. 1986. Poligon: A System for Parallel Problem Solving, Technical Report, KSL-86-19, Dept. of Computer Science, Stanford Univ.

\smallskip \noindent \textit{Dissertation or Thesis}\\
Clancey, W. J. 1979b. Transfer of Rule-Based Expertise through a Tutorial Dialogue. Ph.D. diss., Dept. of Computer Science, Stanford Univ., Stanford, Calif.

\smallskip \noindent \textit{Forthcoming Publication}\\
Clancey, W. J. 1986a. The Engineering of Qualitative Models. Forthcoming.

\section{Producing Reliable PDF\\Documents with \LaTeX{}}
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\section{Abstract}
Semantic mapping is the task of providing a robot with a map of its environment beyond the open, navigable space of traditional Simultaneous Localization and Mapping (SLAM) algorithms by attaching semantics to locations. The system presented in this work reads door placards to annotate the locations of offices. Whereas prior work on this system developed hand-crafted detectors, this system leverages YOLOv2 for detection and a segmentation network for segmentation. Placards are localized by computing their pose from a homography computed from a segmented quadrilateral outline. This work also introduces an Interruptable Frontier Exploration algorithm, enabling the robot to explore its environment to construct its SLAM map while pausing to inspect placards observed during this process. This allows the robot to autonomously discover room placards without human intervention while speeding up significantly over previous autonomous exploration methods.

\section{Introduction}
Simultaneous Localization And Mapping (SLAM) techniques provide navigational maps that enable robots to autonomously explore an environment, while emerging Semantic Mapping techniques add semantic information about locations and objects in the environment. Semantic mapping enables robots to navigate based on a location's semantics rather than simple geometric poses, and by extension allows the robot to reason about locations using automated planning or based on semantic parses of natural language commands \cite{thomason2020jointly}. Semantic maps can be particularly useful for consumer-facing robotic applications, such as aiding visitors in navigating an unfamiliar building \cite{Yedidsion_multi_robot} or object retrieval \cite{Jiang_Walker_Hart_Stone_2019}. Manually labeling map semantics can be tedious or impractical for large maps. This work focuses on the autonomous semantic labeling of a mapped environment.

Buildings often feature signage that annotates important semantics for the benefit of human occupants, such as the placards indicating office numbers. Prior work used hand crafted detectors to identify door placards, register their position on a map, and transcribe their labels~\cite{Hart}~\cite{Case}. These methods require either the construction of a map prior to scanning for placards, or for a human to guide the robot while scanning for placards. One contribution of this work is to simultaneously explore a new environment and register placards without human guidance through the use of an updated Frontier Exploration algorithm, called Interruptable Frontier Exploration (IFE).

Interruptable Frontier Exploration explores the robot's environment, while an object detector scans for door placards. This process is referred to as \emph{passive observation}. Once a sign has been detected, the exploration is interrupted and the robot performs an \emph{active observation}; in which it moves into an optimal position to segment, transcribe, and register the sign's position on the robot's map. To demonstrate the performance of IFE, we compare against a method which computes a robot motion trajectory to scan for placards along previously-discovered sections of wall~\cite{Case}. We call this procedure Wall-Scanning Discovery (WD). IFE takes significantly less time to perform than WD by performing fewer active scans and not requiring a full map before scanning for placards.

\section{Related Work}

Simultaneous Localization and Mapping (SLAM) refers to the problem of exploring a new environment, mapping the features of that environment, and placing the robot on the map~\cite{cadena2016past}. Semantic Mapping is the problem of placing semantic labels on map features~\cite{sunderhauf2017meaningful} for efficient task completion~\cite{aydemir2011plan}~\cite{pronobis2012large} or natural communication with humans. Semantic SLAM tackles both problems at once, often using semantic labels in the localization process~\cite{bowman2017probabilistic}.

Much of the work on Semantic Mapping and Semantic SLAM, has focused on identifying object labels with the sensor being considered, often with RGB or RGB-D cameras~\cite{nakajima2018efficient}~\cite{sunderhauf2017meaningful}~\cite{8794344}, although identifying rooms and spaces is also a common problem~\cite{7487234}. Objects are placed onto a map using a representative model ranging from detailed 3D models~\cite{hosseinzadeh2019real}, to bounding ellipsoids and cubes~\cite{8794344}, or a labelled point cloud and voxel grid~\cite{yu2018variational}.

Many Semantic Mapping and SLAM procedures require image segmentation as a core component. Image segmentation is the problem of assigning pixel-level labels to an image, thereby capturing the shape and precise outline of an object in frame. Convolutional Neural Networks (CNN) are commonly used for this task~\cite{wang2018understanding}.

Labels are generally categorized a-priori by type, without discrimination between instances of the same type~\cite{sualeh2019simultaneous}. An alternative is to discover labels through text embedded in the environment that uniquely identify the object or space around it, thereby improving the specificity of the semantic map. This approach is the subject considered by this paper. There are two major investigations which we expand upon. The earliest work is Autonomous Sign Reading (ASR) for Semantic Mapping~\cite{Case}, and the other is Pose Registration for Integrated Semantic Mapping (PRISM)~\cite{Hart}. While prior work focuses on design of placard detectors, this paper focuses on an efficient discovery method for improved autonomy.

\section{Placard Discovery Methodology}
This system enables a robot to generate SLAM maps and semantic labels for room signage. During an autonomous exploration, RGB and depth image data from an onboard Microsoft Kinect is used to detect possible placards, localize placard positions, and extract signage text. The process for discovering and registering placards is composed of four primary components: (1) \textbf{exploration}, (2) \textbf{placard discovery}, (3) \textbf{sign localization}, and (4) \textbf{text transcription}.

The \textbf{exploration} component is performed by frontier exploration to generate a SLAM map. Frontier search maps are represented by a discretized occupancy grid with cells giving the likelihood of occupation. The occupation grid used for this work has a cell density of $0.5m$. This algorithm and our usage of it is described in more detail below.

For the \textbf{discovery} component, we compare the Wall-Scanning Discovery (WD) and Interruptable Frontier Exploration (IFE) approaches. In WD, \textbf{exploration} happens before \textbf{discovery}, while in IFE they happen simultaneously.

Once a placard has been discovered, \textbf{localization} begins. A fully convolutional neural network performs semantic segmentation to label the sign in an RGB image. The corners of the placard are extracted from the semantically segmented image which enables placard localization.

After localization, is \textbf{text transcription}, in which text is extracted from the image for annotation. For this component, we leverage Tesseract OCR~\cite{tesseract_ocr}.
\subsection{Frontier Exploration}
The grid map that frontier exploration utilizes is initialized with all cells set to the unexplored state. Incoming sensor data updates the observable cells to either occupied or open. \textbf{Frontier cells} are defined as open cells lying next to an unexplored cell. During exploration, the robot navigates to frontier cells until there are none remaining, indicating there are no unseen reachable cells~\cite{Yamauchi}.

Adjacent frontier cells are clustered blobs, and frontiers are tracked by maintaining a list of blobs. Blobs smaller than $10$ cells are pruned from the list. Navigation targets are selected by identifying the closest centroid of the remaining frontier blobs. After an attempted navigation to a centroid (success or failure), the list is updated.

Expanding Wavefront Frontier Detector (EWFD)~\cite{EWFD} is an optimization of frontier exploration algorithm which saves previously explored space to reduce the search space for new frontiers, enabling practical usage in large search areas. EWFD is the variant utilized by this paper. The ROS costmap\_2d package is used to maintain the underlying occupation grid.

\subsection{Wall-Scanning Discovery}
WD is inspired by the work of Case et al. (\citeyear{Case}), adapted for our use. It places waypoints along every wall on a map and visits each, scanning the wall imaged in these poses for placards. Thus, exploration must be completed before scanning can be performed. \algoref{exhaustive} defines the WD procedure, as well as the method for selecting waypoints in the GetWaypoints procedure, using the following parameters:
\begin{itemize}
\setlength
\item \textbf{costmap:} 2D occupancy grid for frontier exploration.
\item \textbf{threshold:} determines weather a cell is occupied or not.
\item \textbf{spacing:} desired spacing of the waypoints along walls.
\item \textbf{distance:} desired distance from the wall to scan.
\end{itemize}

During the Preprocessing step of \algoref{exhaustive}, the costmap is thresholded to convert it into a binary occupation grid. The Canny edge detector~\cite{Canny} is then used to identify the boundary between obstacles and open space, thereby marking the walls that need to be scanned for placards. Line segments are extracted from the set of edges using a Hough Transform~\cite{Hough}.

Whereas prior work identified line segments in the open space of the costmap~\cite{Case}, we found it was more practical to detect the edges first and translate them into the open space. This method enables more control over how close the robot gets to the wall during an active scan. \figref{waypoints} shows an example selection of waypoints generated in our simulated environment.

To determine the direction each segment should be translated by, the perpendicular direction facing away from the occupied space is found in the function GetNormalVector in \algoref{exhaustive}. The line segment is then moved in that direction by the desired distance. Waypoints are then placed at evenly spaced intervals separated at the desired spacing; if the length of the segment is shorter than the spacing, the midpoint is used instead. Once all the edges have been processed, the complete list of waypoints is returned.

The robot is repeatedly commanded to reach the nearest waypoint, removing each one upon success or failure. Assuming the map is fully explored and the Hough Transformation is well tuned, this procedure will assure that the robot scans all parts of the walls. However, traversing such a large set of waypoints essentially means the robot has to traverse the entire environment twice: once to form a costmap, and once again to scan every section of every wall.

\input{ws_algorithm}
\input{fig_waypoints}

\subsection{IFE Discovery}
\algoref{interruptable} defines the IFE procedure. It takes the minimum and maximum range from which to observe placards as a parameter. As the exploration proceeds, the RGB camera feed is scanned with an object detector, and if the placard class label appears, exploration is interrupted. While interrupted, the map is not updated and the robot ceases navigation towards frontier cells.

During interruption, a waypoint with a better view of the detected placard is chosen. This process requires a depth view of the current image frame to identify where the placard is in the scene, the bounding box of the placard in the image frame, and the aforementioned range to observe it from.

\input{ife_algorithm}
This work uses the You Only Look Once (YOLO) neural network for object detection. The base YOLO model can process images at around 45 frames per second~\cite{Yolo}, and YOLOv2 can process 40fps with enhanced accuracy~\cite{YoloV2}. This allows the robot to passively scan the walls for placards without slowing travel during the exploration, and to notice placards from a distance without relying on detailed views. This detector provides bounding box of the placard in the image frame.

GetWaypoint of \algoref{interruptable} defines the procedure for choosing a waypoint from which to scan for placards. The depth image is filtered such that only the points in the placard's bounding box are considered, then remaining depth values are projected onto a point cloud in world coordinates.

The points lying within the bounding box can reasonably be assumed to lie on the placard's face. The point cloud is fitted to a plane to get the orientation of the placard, ensuring that the normal vector is pointed towards the robot.

The position and orientation of the waypoint is determined by the vector normal to the face of the placard and the viewing distance. IFE includes a variable viewing distance to handle cases in which the placard is visible, but a shorter obstacle exists in front of the wall.

A variable distance viewpoint is a significant distinction from WD which will navigate to the specified distance from the obstacle. WD does not have information regarding placard location before setting waypoints, whereas IFE benefits from the passive scan. The consequence is potentially low resolution views from which text cannot be read in WD.

Once the robot has driven to the chosen waypoint and scanned the placard, the exploration process resumes.

\subsection{Placard Localization}
Localizing the placard happens in two steps: segmenting the image with semantic labels for the placard, and extracting the corners of the placard from the semantic segmentation to compute a transformation into world coordinates. Given the placard corners in image frame, the homography to the placard can be computed because it is a known planar target~\cite{Hart}.

\subsubsection{Image Segmentation}
Image segmentation gives pixel level labels for an image. In this case the labels are a binary classification for identifying placards. The image segmentation is done by a fully convolutional neural network with architecture inspired by AlexNet~\cite{long2015fully}. Collecting training data for real robots would require hand labeling the placards. With the gazebo simulator~\cite{koenig2004design}, auto-labelling was done by altering the placard model color and identifying the pixels which changed between frames.

\subsubsection{Corner Detection}
Given a segmentation of a binary classification of a placard, corners are extracted as follows:

\begin{enumerate}
\setlength
    \item Minimum bounding box extraction with edge margin
    \item Canny edge detection~\cite{Canny}
    \item Hough Line transform over edges~\cite{Hough}
    \item K-mean clustering of Hough lines with K=4
    \item Intersection points of k-lines within bounding box
\end{enumerate}
If multiple placards are in view, they are handled separately by isolating contiguous placard regions. This system uses OpenCV's \textit{cv::findContours()} for this purpose~\cite{opencv_library}. \figref{placard} shows an example corner extraction.

\begin{figure}[h]
  \centering
  \includegraphics[width=0.6\linewidth]{placard.jpg}
  \caption{Simulation of placard colored red. Overlaid green lines indicate k-means cluster centers of Hough lines. Dark blue circles indicate corner detections at line intersections.}
  \figlabel{placard}
\end{figure}

\subsubsection{Homography Computation}

Using the ground truth dimensions of a placard, a homography can be computed between the placard and the virtual placard in the camera's image plane. The simulated placards measure $151$mm $\times$ $51$mm. The correspondences between extracted corners of the virtual placard $x'$ and the model placard $x$, is defined by homography $H$ through the relation $x' = Hx$.

\subsubsection{Placard Pose Extration}

With four correspondences, the homography $H$ can be computed using the Direct Linear Transformation (DLT) method~\cite{Hartley}. From this homography the rigid transformation between the placard and the camera can be inferred ~\cite{zhang2000flexible}. The camera extrinsics can be found from $H$ by using the known camera intrinsics, as in Equation \ref{eq:hom_invert_k}, giving us the placard pose relative to the camera frame, as described in Equations \ref{eq:rotation_columns} through \ref{eq:hom_invert_k}.
\vspace{-0.05pc}
\begin{align}
    R = \left[\begin{array}{@{}c c c@{}}r_1 & r_2 & r_3 \end{array}\right] \label{eq:rotation_columns} \\
    x' = K \left[\begin{array}{@{}c c c@{}} r_1 & r_2 & t \end{array}\right]x \label{eq:hom_x_to_x} \\
    K^{-1}H =  \left[\begin{array}{@{}c c c@{}}  r_1 & r_2 & t \end{array}\right] \label{eq:hom_invert_k}
\end{align}

\noindent Where $K$ is the intrinsic matrix, $R$ is camera orientation, and $t$ is the translation from the camera to points on the homography~\cite{zhang2000flexible}. Registration in the robot's map is a matter of transforming the resultant 3D pose with respect to the pose of the camera in the map frame.

\subsection{Text Extraction}
The computed homography is also used to aid in text extraction. The OpenCV \cite{opencv_library} function \textit{cv::warpPerspective()} is used to rectify the input image. TesseractOCR \cite{tesseract_ocr} is run on the rectified image to obtain text, which is stored in the semantic annotation.

Image segmentation, corner detection, homography computation, and text extraction comprise active scanning.

\section{Evaluation}
The system is tested in a Gazebo simulation of our building. Performance of IFE vs WD is assessed on the following:
\begin{enumerate}
  \item Wall coverage (percentage of walls scanned for placards through active and passive scanning)
  \item Number of placards found or missed
  \item Percent of placards correctly identified by room number
  \item Runtime of the algorithm
\end{enumerate}
By running our experiments in simulation we have access to ground truth position of placards and thus are able to evaluate the accuracy of registered placard pose.

IFE is expected to take significantly less time than WD without compromising placard detection and identification.

As this project is still a work in progress, we currently localize the robot with ground truth knowledge of the map, so the environment mapping is more accurate than one would expect without implementing any handling of loop-closure.

\section{Results}

Results in simulation indicate that the YOLOv2 detector has few false positives. Furthermore, the YOLOv2 detector accurately detects placards from steep angles, such as placards on the walls of long, narrow hallways the robot must travel in. Thus each additional placard only contributes on the order of ten seconds of interrupt time compared to a frontier exploration with no interrupts.

WD takes on average close to $30000$ seconds to complete the task, while IFE takes under $3800$; an order of magnitude improvement. This drastic improvement between the two algorithms is because WD must explore the space twice, while also taking additional time to observe empty wall space. Because of the substantially longer run time of WD, fewer trials were collected due to time constraints. A total of $10$ IFE trials and $5$ WD trials were collected.

\tabref{coverage} shows how much of the walls are seen during passive and active scanning. Passive scanning is measured by the overlap between observed and ground truth occupation grids, although is only relevant to IFE. Active scanning is calculated as a proportion of the observed edges. IFE appears substantially smaller because the perimeter of the space is never observed. IFE scans fewer walls, without missing opportunities to spot placards. IFE is designed to limit the amount of active scans necessary. The passive scans have similar performance, while IFE actively scans less than a fifth as much of WD.

\begin{table}[h!]
\centering
\begin{tabular}{|c | c | c|}
 \hline
 \% Wall Coverage & Passive & Active \\ [0.5ex]
 \hline
 WD & 68.92 & 23.17 \\
 \hline
 IFE & 66.82 & 4.15 \\
 \hline
\end{tabular}
\caption{Active and Passive scanning coverage comparison}
\tablabel{coverage}
\end{table}

\tabref{stats} Shows the remaining performance statistics. TPR refers to the true positive rate, the proportion of existing placards recorded, with noticeably better performance using IFE. E[FP] is the expected number of false positives, the number of times a placard will be recorded when it does not exist, IFE again outperforms by this metric. P(err $|$ TP) is the probability of a reading error while scanning a true positive, indicating that the text label could not be determined, performance is about even. E[$\Delta x |$  TP] is the expected error in localization during a scan of a true positive in meters.

\begin{table}[h!]
\centering
\begin{tabular}{|c | c | c | c | c|}
 \hline
 Placards & TPR & E[FP] & P(err $|$ TP) & E[$\Delta x |$ TP] (m) \\ [0.5ex]
 \hline
 WD & 0.69 & 2.6 & 0.43 & 0.47 \\
 \hline
 IFE & 0.88 & 0.44 & 0.46 & 0.31 \\
 \hline
\end{tabular}
\caption{Placard discovery statistics}
\tablabel{stats}
\end{table}

\vspace{-1.2pc}
\section{Conclusion}
This paper proposes a method for semantically mapping an environment without relying on human guidance or relying on prior knowledge of the map, with a focus on identifying wall placards. This IFE procedure is an order of magnitude faster than the WD procedure, and identifies placards more consistently with fewer mistaken registrations.

\section*{Acknowledgements}
This work has taken place in the Learning Agents Research Group (LARG) at the Artificial Intelligence Laboratory, The University of Texas at Austin.  LARG research is supported in part by grants from the National Science Foundation (CPS-1739964, IIS-1724157, NRI-1925082), the Office of Naval Research (N00014-18-2243), Future of Life Institute (RFP2-000), Army Research Office (W911NF-19-2-0333), DARPA, Lockheed Martin, General Motors, and Bosch.  The views and conclusions contained in this document are those of the authors alone.

\bibliographystyle{aaai.bst}

redpajama_set_name: RedPajamaArXiv


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text:
Case Study Review
Ahmad Muhammad
Rosor participates in the first drone inspection of the London International Airport runway.
in an active, towered, and BUSY airport! 6300ft, 1.26 million square feet all captured at 2mm resolution! Through a partnership between Rosor and students of Fanshawe College Norton Wolf School of Aviation and Aerospace Technology, a runway drone inspection was performed at London International Airport.
On Tuesday, Sept. 20th, nearly two kilometers of the runway were closed for the morning while a team of students and faculty from Fanshawe and Rosor, collected real-time data for safety auditing such as cracks, buckling, or sloping in the pavement.
An aerial view of the runway at London International Airport from a drone. The data will be used for future maintenance. (Source: ROSOR)
"People are always concerned about integrating drones with airport operations," says Bruno Alvarenga, a former air traffic controller from Brazil and Fanshawe graduate.
"They always think it's a hazard, but we're here now today to prove that it does actually work," he adds. "We are in touch with the air traffic controllers during all the time and with the tower and all the pilots knows what we are doing at this spot and we are always spotting and seeing the planes operating."Prior to the COVID-19 pandemic, Alvarenga had the idea to use his skills to perform this task. The drone was brought in by ROSOR out of Toronto, and the inspection was underway.
"We are using the drone to take a look at the runway itself," says Adam Debevec, program coordinator of the Norton Wolf School of Aviation and Aerospace Technology at Fanshawe. "So is there is there any issues with cracks, slope of the runway or drainage off the sides of the runway?"
With the drone in hand of ROSOR's co-founder and Chief Technical Officer Robel Efram, they sent it up more than 30 metres above the ground.
"The camera is pointing directly at the runway," says Debevec. "There's a lot of overlap that needs to be accounted for between all those photos. It's thousands of photos, we stitch them together, and we create a 3D model that we can put into a database."
It creates a baseline, and after more frequent inspections are done, they can layer them on top of each other and look for changes.
It's the first time drone technology has been used at LIA. Officials believe the more precise data can help with future maintenance programs.
"So that we can look at the amount of crack sealing material we need to order or the amount of paint we need order for the runway markings," says Steve Faulkner, operations manager at LIA.
He adds, "Instead of doing it based on the traditional manner, which was sort of estimate year-to-year what we're going to need, now we're going to be able to quantify that."
With the Fanshawe program located at LIA, it's a perfect fit for them to continue to work together.
A Rosor drone flies above the runway at London International Airport on September 20, 2022. The data collected will be used for future maintenance at the airport. (Brent Lale/CTV News London)
"They not only tenants here at the airport, but a great school, a great organization," says Faulkner. "We're very excited about being able to work with administrations that strengthen that partnership and look at a long-term relationship between our two organizations."
The students, which included Will Su, a ten-year pilot from China, were also getting practical experience. He was helping the drone operation by monitoring tower and ground frequencies.
"It's critically important that we get them into the real world, so they can understand how these tools can be integrated into various commercial processes," says Debevec, referring to the work done by his students.
He adds, "Students worked on planning what we did here today. They're here observing and supporting and the data that gets pulled into the classroom, they're going to work on that at the end of the line. They have full involvement in the entire process, and that's critical to the school and the program."
Fanshawe College aviation students teamed up with ROSOR out of Toronto to survey the runway at London International Airport on September 20, 2022. The data will be used for future maintenance. (Brent Lale/CTV News London)
The London International Airport's first-ever drone runway safety inspection took place Tuesday morning spearheaded by a team from Fanshawe College in partnership with Rosor, a Toronto-based drone inspection company. (Michelle Both/CBC)
The source coverages;
from Brent Lale/ CTV News https://london.ctvnews.ca/drones-and-airports-can-mix-fanshawe-college-students-use-technology-to-monitor-airport-runway-1.6076316
From Michell Both / CBC London https://www.cbc.ca/news/canada/london/fanshawe-students-innovate-drone-runway-inspection-at-london-international-airport-1.6589160
Drone Photogrammetry
Drone Inspection
London International Airport
ROSOR's Specialized RPAS Technology for Geophysical Surveys; Comparison and Downstream Impact
Future of Mineral Exploration | ROSOR's Specialized Technology
Environmental Impact and Economic Drawbacks of traditional aircraft geophysical surveys

redpajama_set_name: RedPajamaCommonCrawl


Treating meth addictions in an inpatient rehab center may be the solution to sobriety. Incorporating natural remedies can provide successful outcomes. Such remedies include spiritual counseling and physical fitness, as well as nutritional counseling. Meth addiction can be complicated to overcome, but approaching the addiction by various modalities can prove to be worthwhile.
Each aspect of care provided while living in an inpatient rehab center provides its own unique qualities and benefits that can lead to sobriety. For example, physical fitness allows the resident to exert built up stress and emotions through physical exertion. Additionally, physical activity is known to produce endorphins, which induces euphoria and happy feelings. Once a resident witnesses the positive benefits of physical activity, they are likely to incorporate it into their daily routines.
Spiritual counseling can provide residents with the peace of mind that everyone needs. A sense of faith and spirituality often serves as a solid foundation when one faces several challenging life-altering decisions. Religion is not necessarily pushed onto residents, but religion is certainly respected for those residents who observe a particular religion.
Mental counseling helps residents overcome meth addictions by confronting issues that may be the root cause of addictive patterns. Embracing this is essential for full sobriety. One has to understand why they behave in a certain way in order to facilitate changes to those behaviors. Once a resident understands what the underlying issue has been in their lives, they typically feel relieved and can embrace treatment with an open mind. This multi-dimensional meth treatment model can help residents embrace treatment programs for meth addiction that lead to lifelong sobriety, as well as improved behavioral patterns.
For more information on meth addictions and how we can help overcome this, please contact one of our highly skilled professionals today.


The College for Creative Studies together with an advertising firm Team Detroit came up with an ingenious ad concept to attract students to their art courses. Instead of bragging how good the college is, they decided to use reverse psychology.
The ads supposedly discloses harmful and addictive side effects of art, and is also mocking popular anti-drug campaign from the 1980′s and 90′s, put together by the Public Service Announcements.
The idea was conceptualized by Marcus Popiolek, director of marketing at CCS, Kate Lees and Megan Mesack, both of the university. The first campaign was posted in 2011, and the witty irony instantly went viral on social networks. Below are the ads from the older campaign mixed with a couple of new ones which were released this year.


In 1915, flour production in Minneapolis peaked at about two million barrels. From there, the mills started a slow descent from world leadership to only a memory of their former glory. In 1880, Minneapolis was known as the "Flour Milling Capital of the World," or simply, "Mill City." In 1928, a number of mills formed together into one company, General Mills, and from then on the two names most associated with milling would be General Mills and Pillsbury. After World War I, flour milling in Minneapolis entered a period of significant decline. By 1930, the great Mill City had become a shadow of its former self.
The early advantages of Minneapolis mills - power provided by the falls and their innovative milling techniques - ceased to provide a competitive edge. The Red River Valley was experiencing declining crop fertility and the southeastern farms began adopting harder wheat varieties. While a few millers kept their headquarters in Minneapolis, such as General Mills and Pillsbury, most millers moved away from Minneapolis.
Although few true millers remain in Minneapolis, the city has found ways to honor its heritage. For nearly eighty years up until 1960, Minneapolis' baseball team was called the Millers. The city's Gold Medal Park, named after the Washburn-Crosby company's award-winning flour, was opened in 2007 and borders the old milling district and St. Anthony Falls. The Washburn A. Mill closed in 1965 and when it was destroyed by a fire in 1991, the Minnesota Historical Society converted it into the Mill City Museum. The museum hopes to lead visitors to discover how the milling industry of the city "transformed a region and influenced our world." Currently, the museum is in the process of preserving the Washburn-Crosby Elevator No. 1, one of the first and largest circular grain storage units. From the southeastern pioneer farms to the northwestern bonanza farms, from St. Anthony Falls to the city's milling district, the rich wheat farming and milling industries are heavily integrated into the city's legacy. These living memories, the museum and the park, show that Minneapolis strives to preserve more than a mill; the city is preserving its history and the legacy of wheat and flour in the city.
Takuya Amagai, Sahree Kasper, and the Minnesota Environments Team, "Legacy of Milling," Minnesota Environments, accessed April 26, 2019, http://mnenvironments.carleton.edu/items/show/29.
On flour production numbers and years, see David Danbom, Minnesota History Magazine (St. Paul, MN: 2003), 58, no. 5-6 (2003): 270-85, "Flour Power: The Significance of Flour Milling at the Falls."


text:
Q: Как изменить стили select в materialize Нужно изменить стили select, но он не реагирует. Materialize подключал через cdn.

$(document).ready(function () {
    $('select').formSelect();
});
option {
   color: red;
   background: #000;
}
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/materialize/1.0.0/css/materialize.min.css">

     <select class="">
       <option value="" disabled selected>Choose your option</option>
       <option value="1">Option 1</option>
       <option value="2">Option 2</option>
       <option value="3">Option 3</option>
     </select>

A: P.S.: Пользуйтесь браузерным инспектором

$(document).ready(function() {
  $('select').formSelect();
});
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/materialize/1.0.0/css/materialize.min.css">

  <select class="">
    <option value="" disabled selected>Choose your option</option>
    <option value="1">Option 1</option>
    <option value="2">Option 2</option>
    <option value="3">Option 3</option>
  </select>

redpajama_set_name: RedPajamaStackExchange


text:
using System;
using System.IO;
using System.Linq;
using Microsoft.VisualStudio.Modeling.Integration;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Microsoft.VisualStudio.TextTemplating.VSHost;
using Moq;
using NuPattern.Runtime.UriProviders;
using NuPattern.VisualStudio.Extensions;
using NuPattern.VisualStudio.Solution;

namespace NuPattern.Runtime.UnitTests.UriProviders
{
    public class TextTemplateUriProviderSpec
    {
        internal static readonly IAssertion Assert = new Assertion();

        [TestClass]
        public class GivenATemplateProvider
        {
            [TestInitialize]
            public void Initialize()
            {
                this.Templating = new Mock<ITextTemplating>();
                this.ModelBus = new Mock<IModelBus>();
                this.UriService = new Mock<IUriReferenceService>();
                this.UriProvider = new TextTemplateUriProvider(this.Templating.Object, this.ModelBus.Object, new Lazy<IUriReferenceService>(() => this.UriService.Object));
            }

            protected Mock<ITextTemplating> Templating { get; private set; }
            protected Mock<IModelBus> ModelBus { get; private set; }
            protected Mock<IUriReferenceService> UriService { get; private set; }
            protected IUriReferenceProvider<ITemplate> UriProvider { get; private set; }

            [TestMethod, TestCategory("Unit")]
            public void WhenExtensionRelativeUriCannotResolveExtension_ThenReturnsNull()
            {
                var template = this.UriProvider.ResolveUri(new Uri("t4://extension/bar/template.t4"));

                Assert.Null(template);
            }

            [TestMethod, TestCategory("Unit")]
            public void WhenExtensionRelativeUriCannotFindRelativePath_ThenReturnsNull()
            {
                this.UriService
                    .Setup(x => x.ResolveUri<IInstalledExtension>(It.IsAny<Uri>()))
                    .Returns(Mocks.Of<IInstalledExtension>().First(x => x.InstallPath == "C:\\Temp"));

                var template = this.UriProvider.ResolveUri(new Uri("t4://extension//bar/template.t4"));

                Assert.Null(template);
            }

            [DeploymentItem(@"Core\UriProviders\TemplateWithTemplatePath.t4", @"Core\TextTemplateUriProviderSpec\WhenExtensionRelativeFileExists_ThenReturnsValidTemplate")]
            [TestMethod, TestCategory("Unit")]
            public void WhenExtensionRelativeFileExists_ThenReturnsValidTemplate()
            {
                this.UriService
                    .Setup(x => x.ResolveUri<IInstalledExtension>(It.IsAny<Uri>()))
                    .Returns(Mocks.Of<IInstalledExtension>().First(x => x.InstallPath == new DirectoryInfo(@"Core\TextTemplateUriProviderSpec\WhenExtensionRelativeFileExists_ThenReturnsValidTemplate").FullName));

                var template = this.UriProvider.ResolveUri(new Uri("t4://extension/test/TemplateWithTemplatePath.t4"));

                Assert.NotNull(template);
            }
        }
    }
}

redpajama_set_name: RedPajamaGithub


text:
With the clock winding down, and the Lakers trailing by just one point, they put the ball in LeBron's hands, and let him go to work.
The Lakers signed James during the offseason with high hopes, but Los Angeles hasn't had the season it expected. To make matters worse, the 124-123 loss came after James was blocked in the closing seconds by Mario Hezonja, which not only sealed the loss but capped the worst shooting quarter of "The King's" career. Ir wash the Lakers' third consecutive and fell to 31-39 in the standings, nine games out of the playoffs picture in the Western Conference. It bothers me that I didn't even get a shot at the hoop. In public, you've got to be part of the team. Knicks TV analyst Walt Frazier criticized James for not publicly being more part of the team, saying James "doesn't really care" about the perception.
The drama-filled season may be on life support, with only a marginal mathematical chance of them playing post-season basketball, but that doesn't mean that these final two and a half weeks of the season are lost for Kuzma.
More news: Ernesto Valverde: Treble-seeking Catalans took important step with Real Betis win
James said after the loss that he saw "no difference" between the woeful Knicks and his own squad, calling them "two teams out of the postseason", and adding, "We could have a couple of more wins than them, but both teams right now are looking on the outside looking in".
Trying to turn a negative into a positive, the second-year star has turned his attention to using his remaining minutes of the 2018/19 Lakers season the season to develop his game further and get some reps up before another long summer. After missing 12 games with a leg injury.
Though rookie Kevin Knox has shot miserably in his first season, Fizdale thought games like Sunday and then Monday against Toronto were good for the first-round pick, no matter how he shot, because they were learning experiences. There's no rule that says if you have a bunch of younger teammates next to LeBron James. He's signed for three more seasons, but questions persist around head coach Luke Walton and nearly everyone else on the roster's future.
Death toll rises to 50 in New Zealand mosque shootings
She said this would be looked at as the Government moved to change gun laws but there were a "raft of issues" to look at. The camera attached to his head recording the massacre follows the barrel of his weapon, like some macabre video game.
Senate Demands Trump End US Support for War in Yemen
The US Senate approved SJ Res 7 on Wednesday that calls for the removal of US military from hostilities in the Republic of Yemen. But it is significant and important that Congress - both houses of Congress - will have voted to rebuke Trump's abuses of power.
GBPUSD: Sterling Slips After Latest Brexit Votes Approve Deadline Pushback
She didn't listen to that, and that's fine. "I think it could have been negotiated in a different manner, frankly", Trump said. Speaking in the Oval Office alongside Irish premier Leo Varadkar, Mr Trump said Brexit was "tearing a lot of countries apart".
Christchurch attack 'shows blind spot on white nationalism'
Dozens of graves were being dug in readiness for that release, which Police Deputy Commissioner Wally Haumaha said he hoped would happen soon.


"Being out of work for so long has really knocked my confidence and self-esteem. Getting this work placement with REPC has been brilliant! I've learned some very useful new skills and mixing with the REPC staff has really improved my social skills"
Matthew Lester joined the BRIDGES project in August 2017.
Matthew had been in skilled jobs and had run his own business in the past, but a very long period of unemployment had left him suffering from very low self-esteem, anxiety and diminished social skills. Matthew was very keen to get back into some form of routine to help himself re-build his self-confidence.
Matthew already had a big interest in IT. REPC Limited is an IT recycling, refurbishing and re-use social enterprise organisation and Matthew was offered a 10-day work placement at the company as an IT technician, providing him with the ideal opportunity to re-build his self-confidence and learn some new technical skills.
Matthew began attending REPC one day per week and over the course of the 10-week programme, with good mentoring and support from the BRIDGES staff, he has been able to re-build his self-confidence whilst developing a range of new IT skills, including computer recycling and refurbishing. His performance has been such that he was offered an extension to the original placement. Matthew is now really looking forward to the future and is keen to take the next steps towards finding paid employment.


text:
Mariano Rivera Always Entered to Metallica, but Doesn't "Listen to That Kind of Music"
The band congratulated the closer on his election into the Baseball Hall Of Fame
Michael Cerio
Al Bello / Staff | Ethan Miller / Staf
The sound of success might just be Metallica.
As Mariano Rivera entered the field, "Enter Sandman" would blare from the speakers of Yankees Stadium, announcing the arrival of the all-time career saves leader, the five-time World Series champion, and the first player ever elected unanimously to the Baseball Hall of Fame.
Related: Metallica Celebrates 30 Years of the "One" Video
The song from the Black Album band is synonymous with the thirteen-time All-Star, who made his first start with the New York Yankees four years after it had been released. The anthem took on a new meaning with Rivera, a siren to warn of the dominance about to be witnessed by fans and opposing hitters alike.
On Tuesday after his undisputed election into the Baseball Hall Of Fame, Metallica offered a congratulations to the closer. ""We Metallica, took a vote here, and it's unanimous. Congratulations from the entire Metallica family Mariano on your induction into the Baseball Hall of Fame" explained singer James Hetfield. "We look forward to watching you enter the Hall this summer" adds Lars Ulrich.
Hey Mo, we've got some old friends that wanted to say congrats. pic.twitter.com/enlwrVpaCc
— Cut4 (@Cut4) January 22, 2019
Rivera was very thankful and gracious, explaining to MLB Network, "I have so much respect for those guys. I met them and they are great people."
When pressed though about his Metallica fandom, Rivera revealed that he is not actually a fan of the band's music. As the hosts asked about how many shows he had been to, Rivera responded "with all due respect to the guys, I've never been to one of them."
"As a Christian, with all due respect to Metallica, I don't listen to that kind of music."
Fair enough. It's strictly mound music for the greatest closer in baseball history.
Mariano Rivera will be inducted into the Hall Of Fame at a ceremony on July 21st. Metallica will continue their WorldWired tour around the country into March, in case the Sandman has a change of heart.


text:
Dating/ /
New York escorts- Celebrate Life with Her
One out of thirty-eight people of the USA stays in the city of New York. The city boasts of a 520-mile coastline which is more than combined coastline of Miami, San Francisco, Los Angeles and Boston. The famous Time Square was known as Longacre Square till 1904. The name is derived from the New York Times. The Empire State Building has its own postal zip code: 10118. The city is really, amazing, lively and mesmerizing. It has so much more to offer. Your mornings and evenings can be colorful every day whenever you want.
A great City
New York is one of the greatest cities in the world, bubbling with activity. Be accompanied by a luscious, vibrant, gorgeous, intelligent, and sumptuous New York escorts to explore the city. It is a great place to shop and dine; there is excitement hidden in every nook and turn. There are many famous sites where you two can visit, talking and walking side by side. Statue of Liberty, Empire State Building, Brooklyn Bridge, Central Park, to name a few. Recent tourist attractions are One World Observatory and High Line.
Take a Boat Ride
The Statue of Liberty, the greatest American icon, was gifted by France to this great nation. This 450,000-pound sculpture 152 ft. Tall from base to the top was built in 1886. You two can have a fine view from Battery Park situated in the southern end of Manhattan. But you two can take a boat ride to Liberty Island to have a closer look to appreciate this world-renowned figure truly. You two can have a grand time with each other`s company walking around the base, entering the podium and with advance booking, you two can go up to the crown of the statue.
The lonely planet
This lonely planet can be truly lonely without a compassionate companionship. She bubbles out your isolation and embraces you to give the comfort, the warmth you carved for so long. Her upbeat, cheery yet loving personality cheers you to the core to celebrate life. You may have masked your emotions, grief, and insecurity from the world. In her companionship, you can be once more the true self, revealing your deepest fears and emotions without apprehension. Companionship, sharing and caring opens another dimension in your emotional world. It teaches you to understand yourself and others better, making the journey of life more evocative, more comfortable.
April Wilcox
How mobile apps and services have changed the world of New York Escorts?
What Makes A Good Dating Profile?
How to Wash Silicone Love Doll Vagina after Using?
Transsexuals for Working Men


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