removed stuff for anonymous double blind mumbo, and submitted

dp2041 [2004-04-25 17:24:36]
removed stuff for anonymous double blind mumbo, and submitted
Filename
paper/ai2tv-acm-mm-2004-submitted.pdf
paper/ai2tv.tex
diff --git a/paper/ai2tv-acm-mm-2004-submitted.pdf b/paper/ai2tv-acm-mm-2004-submitted.pdf
new file mode 100644
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diff --git a/paper/ai2tv.tex b/paper/ai2tv.tex
index 6a0954e..9e19ce9 100644
--- a/paper/ai2tv.tex
+++ b/paper/ai2tv.tex
@@ -3,64 +3,11 @@
 % $Date$
 % $Source$
 %
-%
 % ---------------------------------------------------------------------------
 % TODO:
 %
-% FINAL READ
-% - check for consistent tense
-% - query replace: ai2tv -> $\mathrm{AI}^2$TV
-% - spell check
-%
-%
-% ---------------------------------------------------------------------------
-% This is "sig-alternate.tex" V1.3 OCTOBER 2002
-% This file should be compiled with V1.6 of "sig-alternate.cls" OCTOBER 2002
-%
-% This example file demonstrates the use of the 'sig-alternate.cls'
-% V1.6 LaTeX2e document class file. It is for those submitting
-% articles to ACM Conference Proceedings WHO DO NOT WISH TO
-% STRICTLY ADHERE TO THE SIGS (PUBS-BOARD-ENDORSED) STYLE.
-% The 'sig-alternate.cls' file will produce a similar-looking,
-% albeit, 'tighter' paper resulting in, invariably, fewer pages.
-%
 % ---------------------------------------------------------------------------
-% This .tex file (and associated .cls V1.6) produces:
-%       1) The Permission Statement
-%       2) The Conference (location) Info information
-%       3) The Copyright Line with ACM data
-%       4) NO page numbers
-%
-% as against the acm_proc_article-sp.cls file which
-% DOES NOT produce 1) thru' 3) above.
-%
-% Using 'sig-alternate.cls' you have control, however, from within
-% the source .tex file, over both the CopyrightYear
-% (defaulted to 2002) and the ACM Copyright Data
-% (defaulted to X-XXXXX-XX-X/XX/XX).
-% e.g.
-% \CopyrightYear{2003} will cause 2002 to appear in the copyright line.
-% \crdata{0-12345-67-8/90/12} will cause 0-12345-67-8/90/12 to appear in the
-%  copyright line.
-%
-% ---------------------------------------------------------------------------
-% This .tex source is an example which *does* use
-% the .bib file (from which the .bbl file % is produced).
-% REMEMBER HOWEVER: After having produced the .bbl file,
-% and prior to final submission, you *NEED* to 'insert'
-% your .bbl file into your source .tex file so as to provide
-% ONE 'self-contained' source file.
-%
-% ================= IF YOU HAVE QUESTIONS =======================
-% Questions regarding the SIGS styles, SIGS policies and
-% procedures, Conferences etc. should be sent to
-% Adrienne Griscti (griscti@acm.org)
-%
-% Technical questions _only_ to
-% Gerald Murray (murray@acm.org)
-% ===============================================================
-%
-% For tracking purposes - this is V1.3 - OCTOBER 2002
+
 \documentclass{sig-alternate}
 \usepackage{url}

@@ -76,7 +23,6 @@
 % Allows default copyright data (0-89791-88-6/97/05) to be over-ridden - IF NEED BE.
 % --- End of Author Metadata ---

-% \title{Optimizing Quality for Video Sharing in Synchronous Collaboration}
 \title{Optimizing Quality for Collaborative Video Viewing}
 %
 % You need the command \numberofauthors to handle the "boxing"
@@ -90,45 +36,48 @@
 % these will be set for you without further effort on your
 % part as the last section in the body of your article BEFORE
 % References or any Appendices.
-
-\numberofauthors{4}
 %
 % You can go ahead and credit authors number 4+ here;
 % their names will appear in a section called
 % "Additional Authors" just before the Appendices
 % (if there are any) or Bibliography (if there
 % aren't)
+% \numberofauthors{4}

 % Put no more than the first THREE authors in the \author command
 \author{
+ \alignauthor Authors removed for double blind reviewing.
+}
+
 %
 % The command \alignauthor (no curly braces needed) should
 % precede each author name, affiliation/snail-mail address and
 % e-mail address. Additionally, tag each line of
 % affiliation/address with \affaddr, and tag the
-%% e-mail address with \email.
-\alignauthor Dan Phung\\
-       \affaddr{Computer Science}\\
-       \affaddr{Columbia University}\\
-       \affaddr{New York City, New York}\\
-       \email{phung@cs.columbia.edu}
-\alignauthor Giuseppe Valetto\\
-       \affaddr{Computer Science}\\
-       \affaddr{Columbia University}\\
-       \affaddr{New York City, New York}\\
-       \affaddr{and Telecom Italia Lab}\\
-       \affaddr{Turin, Italy}
-       \email{valetto@cs.columbia.edu}
-\alignauthor Gail Kaiser \\
-       \affaddr{Computer Science}\\
-       \affaddr{Columbia University}\\
-       \affaddr{New York City, New York}\\
-       \email{kaiser@cs.columbia.edu}
-}
-\additionalauthors{Additional authors: Suhit Gupta {\texttt{suhit@columbia.cs.edu}}}
+% e-mail address with \email.
+
+%% \alignauthor Dan Phung\\
+%%        \affaddr{Computer Science}\\
+%%        \affaddr{Columbia University}\\
+%%        \affaddr{New York City, New York}\\
+%%        \email{phung@cs.columbia.edu}
+%% \alignauthor Giuseppe Valetto\\
+%%        \affaddr{Computer Science}\\
+%%        \affaddr{Columbia University}\\
+%%        \affaddr{New York City, New York}\\
+%%        \affaddr{and Telecom Italia Lab}\\
+%%        \affaddr{Turin, Italy}
+%%        \email{valetto@cs.columbia.edu}
+%% \alignauthor Gail Kaiser \\
+%%        \affaddr{Computer Science}\\
+%%        \affaddr{Columbia University}\\
+%%        \affaddr{New York City, New York}\\
+%%        \email{kaiser@cs.columbia.edu}
+%% }
+%\additionalauthors{Additional authors: Suhit Gupta {\texttt{suhit@columbia.cs.edu}}}
+
 \date{\parbox[b][0ex]{0em}{\hspace*{-12.5em}\raisebox{37ex}{\fbox{For
-submission to \emph{ACM-MM 2004}, due 12:00 AM EDT: April 05, 2004.}}}}
-% \date{05 April 2004}
+submission to \emph{ACM-MM 2004}, due 5:00 PM EDT: April 25, 2004.}}}}
 \maketitle

 \begin{abstract}
@@ -166,15 +115,8 @@ the quality level for each participant.

 \keywords{Synchronized Collaborative Video, Autonomic Controller}

-% tech report number CUCS-009-04
 \section{Introduction}

-% The wording was awkward here, so I pretend that Stanford also
-% once fedexed, even tho we don't know that.
-
-% Dan - you didn't insert any of the original cites into the new
-% Introduction, weren't any of them relevant?
-
 Distance learning programs such as the Columbia Video Network and the
 Stanford Center for Professional Development have evolved from
 fedexing lecture video tapes to their off-campus students to instead
@@ -190,8 +132,6 @@ may be an advantage, since on-campus students are rarely afforded the
 opportunity to pause, rewind and fast-forward their instructors'
 lectures.

-% should it be JPG or JPEG?
-
 However, {\em collaborative video viewing} by multiple geographically
 dispersed users is not yet supported by conventional Internet-video
 technology.  It is particularly challenging to support WISIWYS (what I
@@ -266,9 +206,6 @@ contributions.

 \section{Motivation and Background} \label{background}

-% - discuss other projects on multiple client synchronization
-% shouldn't that go in the related work section?
-
 Correspondence courses have been available to working adult and/or
 geographically remote learners for over a century, e.g., the American
 School in Illinois has offered high school courses since 1897
@@ -278,8 +215,6 @@ learning program in 1906 \cite{UWyoming}.  Correspondence courses have
 traditionally been designed for individual students with a
 self-motivated learning style, studying primarily from text materials.

-% would be good if a cite could be found for last sentence above
-
 An NSF Report \cite{NSFReport} discusses how technology, from radio to
 television, to audio and video cassettes, to audio and video
 conferencing, has affected distance education. These technologies have
@@ -314,10 +249,6 @@ synchronous collaboration ``situated'' by collaborative lecture video
 viewing, approximating the experience of on-campus students physically
 attending the lecture and class discussion.

-% would be good to find a cite for the last sentence above
-
-% - ai2tv project goals
-
 Our $\mathrm{AI}^2$TV project aims to contribute to the area of
 synchronous collaboration support for distance education, specifically
 in the context of collaborative video viewing over the Internet.  Our
@@ -353,10 +284,6 @@ resources from a hierarchy of several different encodings for that
 video. Thus a client could receive an appropriate quality of video
 content while staying in sync with the other members of the group.

-% so why isn't the above approach good enough, do we do better?
-
-% - describe overview of semantic compression tool used
-
 We use {\em semantic compression} to produce a video with cumulative
 layering.  A semantic compression algorithm developed by Liu and
 Kender \cite{TIECHENG} reduces a video to a set of semantically
@@ -387,7 +314,7 @@ high frequency semantic change, which result in sections in the video
 that demand a higher frame rate.  The variable frame rate video adds
 substantial complexity to the bandwidth demands of the client.

-Also, in figure \ref{sem_video}, the bottom-left in-set shows the
+In figure \ref{sem_video}, the bottom-left in-set shows the
 juxtaposition of individual frames from two different quality levels.
 Each frame has a representative time interval \texttt{[start:end]}.
 For the higher level, Frame 1a represents the interval from 1:00 to
@@ -430,15 +357,10 @@ Workflakes monitors the video clients and consequently coordinates the
 dynamic adjustment of the compression (quality) level currently
 assigned to each client.

-% (FIGURE: semantic compression )
-% (FIGURE: key frames hierarchy )
-
 \section{Architecture and Adaptation\\ Model}

 \subsection{System Architecture}

-% Design of the system in general
-
 $\mathrm{AI}^2$TV involves several major components: a video server,
 video clients, an autonomic controller, and a common communications
 infrastructure, as shown in figure \ref{ai2tv_arch}.
@@ -450,8 +372,6 @@ infrastructure, as shown in figure \ref{ai2tv_arch}.
   \label{ai2tv_arch}
 \end{figure}

-%(FIGURE: ai2tv synchronization arch)
-% video server
 The video server provides the educational video content to the clients
 for viewing.  Each lecture video is stored in the form of a hierarchy
 of versions, produced by running the semantic compression tool
@@ -460,8 +380,6 @@ run produces a sequence of JPEG frames with a corresponding frame
 index file.  The task of the video server is simply to provide remote
 download access to the collection of index files and frames over HTTP.

-% video client
-
 The task of each video client is to acquire video frames, display them
 at the correct times, and provide a set of basic video functions.
 Taking a functional design perspective, the client is composed of four
@@ -505,7 +423,9 @@ The purpose of the autonomic controller is to ensure that, given the
 synchronization constraint, each client plays at its highest
 attainable quality level.  The controller is itself a distributed
 system, whose design derives from a conceptual reference architecture
-for autonomic computing platforms proposed by Kaiser {\it et al.}
+% for autonomic computing platforms proposed by Kaiser {\it et al.}
+for autonomic computing platforms proposed by
+Anonymous\footnote{Removed for double blind reviewing.} {\it et al.}
 \cite{REFARCH}, which is shown in figure \ref{refarch}. The
 architecture provides an end-to-end closed control loop, in which
 sensors attached to a generic (possibly legacy) target system
@@ -517,10 +437,6 @@ workflow needed to carry out the adaptation.  At the end of the loop,
 actuators attached to the target system effect the needed adjustments
 under the supervision of the controller.

-%
-%(figure of ref arch here).
-%
-
 \begin{figure}
  \centering
  \epsfig{file=refarch.eps, width=8cm}
@@ -543,8 +459,6 @@ coordination engine enacts an adaptation scheme, basically a workflow
 plan, which is executed on the end hosts by taking advantage of the
 hooks provided to the actuators by the clients.

-% communications
-
 Communication among the video clients, as well as between the sensors
 and actuators at the clients and the autonomic controller, is provided
 by a publish-subscribe event bus.  There are three kinds of events:
@@ -569,10 +483,6 @@ parallel steps is dynamically determined via the number of entries in
 the \texttt{clients} variable, which maps to a collection of
 $\mathrm{AI}^2$TV clients.

-%
-%add Figure with AI2TV workflow diagram here
-%
-
 \begin{figure}
   \centering
   \hspace*{-5mm}
@@ -650,21 +560,7 @@ differences resulting from the controller's adaptation of the clients'
 behavior {\it versus} the behavior of the baseline client, with
 respect to synchrony and frame rate.

-%% To evaluate our system, we produced an $\mathrm{AI}^2$TV video that had 5 quality
-%% levels.  For a 17 minute video and five different window lengths, the
-%% total number of frames are 165, 71, 39, 21, and 13.  Our choice of the
-%% relatively low frame rate quality levels was influenced by the goal of
-%% the system being used by clients with low bandwidth resources.
-
-% the pathetic average frame rates (per minute!!!):
-%% 3.399831413 - high
-%% 1.46295776
-%% 0.806289939
-%% 0.434237734
-%% 0.268763313 - low
-
 \subsection{Evaluating Synchronization}
-
 The primary goal of our system is to provide synchronous viewing of
 lecture videos to small groups of geographically dispersed students,
 some possibly with relatively meager resources.  Our initial
@@ -700,28 +596,16 @@ listening to Internet radio, where users must choose a desired frame
 rate to receive.  The user may have been informed that she is
 allocated a certain bandwidth level from her Internet service
 provider, but may actually be receiving a significantly lower rate.
-We ran this set of experiments first without the aid of the autonomic
-controller and then with it. In the former case, clients with
-insufficient bandwidth were stuck at the compression level originally
-selected, and thus missed an average of 63\% of the needed frames.  In
-the latter case, the same clients only missed 35\% of the needed
-frames.  Although both situations are abysmal, these results provide
-evidence of the benefits of the adaptive scheme implemented by the
-autonomic controller.
-
-%% selected, and thus only displayed an average of 37\% of the needed
-%% frames.  In the latter case, the same clients received 65\% of the
-%% needed frames.  These results provide evidence of the benefits of the
-%% adaptive scheme implemented by the autonomic controller.
-
-
-%% \begin{figure}
-%%   \centering
-%%   \hspace*{-5mm}
-%%   \epsfig{file=scores.eps, width=9cm}
-%%   \caption{Comparison of weighted scores}
-%%   \label{scores}
-%% \end{figure}
+The clients were assigned bandwidths one level lower than the preset
+quality level.  We ran this set of experiments first without the aid
+of the autonomic controller and then with it. In the former case,
+clients with insufficient bandwidth were stuck at the compression
+level originally selected, and thus missed an average of 63\% of the
+needed frames.  In the latter case, the same clients only missed 35\%
+of the needed frames.  Although both situations show a significant
+amount of missed frames, these results provide evidence of the
+benefits of the adaptive scheme implemented by the autonomic
+controller.

 \subsection{Evaluating Quality of Service}

@@ -745,8 +629,6 @@ quality, and are not constrained by the group synchronization
 requirement.  This restriction mandates a scoring system sensitive to
 the relative differences between quality hierarchies.

-% qos results
-
 Our experiments show that baseline clients scored a group score of 1
 (as expected) while the controller-assisted clients scored a group
 score of 1.25.  The one-tailed t-score of this difference is 3.01,
@@ -760,8 +642,6 @@ each client is able to enjoy.  We found that, overall, those clients
 received 20.4\% ($\pm$ 9.7, N=17) more frames than clients operating
 at a baseline rate.

-% risk assessment
-
 Running the client close to or at a level higher than the average
 bandwidth needed puts the client at risk for missing more frames,
 because the autonomic controller is trying to push the client to a
@@ -781,12 +661,6 @@ bandwidth available to that client was relatively low.  The client was
 able to consistently maintain a high video quality level after this
 epoch.

-% calculation used for the 20% number I got up there.
-% baselineFrames = number of frames base client gets
-% wfFrames = number of frames the wf client gets
-% (wfFrames - baselineFrames) / baselineFrames = proportion of frames higher
-%                                                then the baseline client
-
 Our $\mathrm{AI}^2$TV system can achieve collaborative video viewing
 using relatively naive NTP-based synchronization, without the
 autonomic controller. But in typical real-world scenarios, network
@@ -925,33 +799,24 @@ have demonstrated the advantages of this approach through experimental
 trials using bandwidth throttling to show that our system can provide
 synchronization of video together with optimized video quality.

-%ACKNOWLEDGMENTS are optional
-\section{Acknowledgments}
-
-We would like to thank John Kender, Tiecheng Liu, and other members of
-the High-Level Vision Lab for their assistance in using their
-lecture-video semantic compression software.  We would also like to
-thank the other members of the Programming Systems Lab, particularly
-Matias Pelenur who implemented PSL's Little-JIL interpreter on top of
-Workflakes/Cougaar.  Little-JIL was developed by Lee Osterweil's LASER
-lab at the University of Massachusetts, Amherst. Cougaar was developed
-by a DARPA-funded consortium; our main Cougaar contact was Nathan
-Combs of BBN.  Siena was developed by the University of Colorado,
-Boulder, in Alex Wolf's SERL lab. PSL is funded in part by National
-Science Foundation grants CCR-0203876, EIA-0202063 and EIA-0071954,
-and by Microsoft Research.
-
-% The following two commands are all you need in the
-% initial runs of your .tex file to
-% produce the bibliography for the citations in your paper.
-% \bibliographystyle{abbrv} \bibliography{ai2tv}
-% \subsection{References}
-%
-%% Generated by bibtex from your ~.bib file.  Run latex,
-%% then bibtex, then latex twice (to resolve references)
-%% to create the ~.bbl file.  Insert that ~.bbl file into
-%% the .tex source file and comment out
-%% the command \texttt{{\char'134}thebibliography}.
+
+% Removed to adhere to anonymity guidelines
+%% \section{Acknowledgments}
+%% We would like to thank John Kender, Tiecheng Liu, and other members of
+%% the High-Level Vision Lab for their assistance in using their
+%% lecture-video semantic compression software.  We would also like to
+%% thank the other members of the Programming Systems Lab, particularly
+%% Matias Pelenur who implemented PSL's Little-JIL interpreter on top of
+%% Workflakes/Cougaar.  Little-JIL was developed by Lee Osterweil's LASER
+%% lab at the University of Massachusetts, Amherst. Cougaar was developed
+%% by a DARPA-funded consortium; our main Cougaar contact was Nathan
+%% Combs of BBN.  Siena was developed by the University of Colorado,
+%% Boulder, in Alex Wolf's SERL lab. PSL is funded in part by National
+%% Science Foundation grants CCR-0203876, EIA-0202063 and EIA-0071954,
+%% and by Microsoft Research.
+
+%  ??? for spacing, to get references on the next column
+\vspace*{10mm}

 \begin{thebibliography}{10}
 \small
@@ -1044,12 +909,13 @@ A.~L. Corte, A.~Lombardo, S.~Palazzo, and G.~Schembra.
 \newblock {\em Multimedia Systems}, 6(2):102--112, 1998.

 \bibitem{CHIME}
-S.~E. Dossick and G.~E. Kaiser.
-\newblock {CHIME: A Metadata-Based Distributed Software Development
-  Environment}.
-\newblock In {\em Joint 7th European Software Engineering Conference and 7th
-  ACM SIGSOFT International Symposium on the Foundations of Software
-  Engineering}, pages 464--475, 1999.
+Reference removed for double blind reviewing.
+%% S.~E. Dossick and G.~E. Kaiser.
+%% \newblock {CHIME: A Metadata-Based Distributed Software Development
+%%   Environment}.
+%% \newblock In {\em Joint 7th European Software Engineering Conference and 7th
+%%   ACM SIGSOFT International Symposium on the Foundations of Software
+%%   Engineering}, pages 464--475, 1999.

 \bibitem{FSP}
 J.~Escobar, C.~Partridge, and D.~Deutsch.
@@ -1077,11 +943,13 @@ A.~J. Gonzalez and H.~Adbel-Wahab.
   2000.

 \bibitem{VECTORS}
-S.~Gupta and G.~Kaiser.
-\newblock {A Virtual Environment for Collaborative Distance Learning With Video
-  Synchronization}.
-\newblock In {\em 7th IASTED International Conference on Computers and Advanced
-  Technology in Education}, August 2004.
+Reference removed for double blind reviewing.
+
+%% S.~Gupta and G.~Kaiser.
+%% \newblock {A Virtual Environment for Collaborative Distance Learning With Video
+%%   Synchronization}.
+%% \newblock In {\em 7th IASTED International Conference on Computers and Advanced
+%%   Technology in Education}, August 2004.

 \bibitem{IBM}
 {IBM}.
@@ -1089,24 +957,27 @@ S.~Gupta and G.~Kaiser.
 \newblock \url{http://www.research.ibm.com/autonomic/}.

 \bibitem{REFARCH}
-G.~Kaiser, P.~Gross, G.~Kc, J.~Parekh, and G.~Valetto.
-\newblock {An Approach to Autonomizing Legacy Systems, in Workshop on
-  Self-Healing, Adaptive and Self-Managed Systems}.
-\newblock In {\em Workshop on Self-Healing, Adaptive and Self-Managed Systems},
-  June 2002.
+Reference removed for double blind reviewing.
+%% G.~Kaiser, P.~Gross, G.~Kc, J.~Parekh, and G.~Valetto.
+%% \newblock {An Approach to Autonomizing Legacy Systems, in Workshop on
+%%   Self-Healing, Adaptive and Self-Managed Systems}.
+%% \newblock In {\em Workshop on Self-Healing, Adaptive and Self-Managed Systems},
+%%   June 2002.

 \bibitem{AMS}
-G.~Kaiser, J.~Parekh, P.~Gross, and G.~Valetto.
-\newblock {Kinesthetics eXtreme: An External Infrastructure for Monitoring
-  Distributed Legacy Systems}.
-\newblock In {\em 5th Annual International Active Middleware Workshop}, June
-  2003.
+Reference removed for double blind reviewing.
+%% G.~Kaiser, J.~Parekh, P.~Gross, and G.~Valetto.
+%% \newblock {Kinesthetics eXtreme: An External Infrastructure for Monitoring
+%%   Distributed Legacy Systems}.
+%% \newblock In {\em 5th Annual International Active Middleware Workshop}, June
+%%   2003.

 \bibitem{AMSJournal}
-G.~Kaiser, J.~Parekh, P.~Gross, and G.~Valetto.
-\newblock {Retrofitting Autonomic Capabilities onto Legacy Systems}.
-\newblock Technical Report CUCS-026-03, Columbia University Department of
-  Computer Science, October 2003.
+Reference removed for double blind reviewing.
+%% G.~Kaiser, J.~Parekh, P.~Gross, and G.~Valetto.
+%% \newblock {Retrofitting Autonomic Capabilities onto Legacy Systems}.
+%% \newblock Technical Report CUCS-026-03, Columbia University Department of
+%%   Computer Science, October 2003.

 \bibitem{OSTERWEIL}
 B.~S. Lemer, E.~K. McCall, A.~Wise, A.~G. Cass, L.~J. Osterweil, and S.~M.~S.
@@ -1195,16 +1066,18 @@ G.~Sidler, A.~Scott, and H.~Wolf.
 \newblock In {\em 8th Joint European Networking Conference Proceedings}, 1997.

 \bibitem{ValettoThesis}
-G.~Valetto.
-\newblock {\em Orchestrating the Dynamic Adaptation of Distributed Software
-  with Process Technology}.
-\newblock PhD thesis, Columbia University, April 2004.
+Reference removed for double blind reviewing.
+%% G.~Valetto.
+%% \newblock {\em Orchestrating the Dynamic Adaptation of Distributed Software
+%%   with Process Technology}.
+%% \newblock PhD thesis, Columbia University, April 2004.

 \bibitem{ICSE}
-G.~Valetto and G.~Kaiser.
-\newblock {Using Process Technology to Control and Coordinate Software
-  Adaptation}.
-\newblock In {\em International Conference on Software Engineering}, May 2003.
+Reference removed for double blind reviewing.
+%% G.~Valetto and G.~Kaiser.
+%% \newblock {Using Process Technology to Control and Coordinate Software
+%%   Adaptation}.
+%% \newblock In {\em International Conference on Software Engineering}, May 2003.

 \bibitem{CEN}
 J.~Walpole, R.~Koster, S.~Cen, C.~Cowan, D.~Maier, D.~McNamee, C.~Pu,
@@ -1225,15 +1098,7 @@ J.~G. Wells.

 \end{thebibliography}

-% This next section command marks the start of
-% Appendix B, and does not continue the present hierarchy
-%% \section{More Help for the Hardy}
-%% The sig-alternate.cls file itself is chock-full of succinct
-%% and helpful comments.  If you consider yourself a moderately
-%% experienced to expert user of \LaTeX, you may find reading
-%% it useful but please remember not to change it.
-
-\balancecolumns % GM July 2000
+\balancecolumns
 % That's all folks!
 \end{document}
 % ---------------------------------------------------------------