[Blindmath] Accessible Physics Concepts for Blind Students

Richard Baldwin baldwin at dickbaldwin.com
Wed Jun 15 13:15:41 CDT 2011

Good comments everyone. I will reply to each comment individually.

John, you wrote

"Any reason we cannot use the link directly to the beginning of your
collection?  Ie

Because I'm not blind and don't use a screen reader or a Braille display to
read online material, I don't have a good answer to that question. Someone
earlier suggested that the landing spot should be the Table of Contents for
the collection instead of the main page for the collection. Apparently that
individual was having difficulty getting to the Table of Contents for the
collection. I am unable to assess the degree of difficulty involved. I am
thinking of modifying my material and providing two links whenever I provide
links, one to the main page for the collection and the other to the Table of
Contents. I will let you be the judge as to which you should use on

Ken, you wrote

"Hmm then could you not just put that stuff in the meta tags rather than the

If this were a typical web site that stores volumes of html files, the
answer would probably be Yes. However, this web site is different, and what
I am getting ready to tell you also applies to Christine's comment later.

This web site doesn't store html files. Instead, it stores CNXML files,
which are a flavor of XML. Thus, the concept of meta tags may not have the
same meaning here as in a web site that stores html files.

The html files that you see when you land on the page don't exist in any
permanent sense. Instead, they are generated on the fly by a program that
converts one or more CNXML files into a very temporary html file for
transmission to the client.

This is a type of website organization for which I have no prior experience,
and I'm not sure what a search engine sees when it visits the site. However,
I am sure that I don't have an opportunity to insert meta tags into the
CNXML file that I create and submit to the site. When i publish a module, I
am given an opportunity to specify a set of keywords, but it is my
impression that they are used strictly for local searching on the site.

I am pretty certain that there is not what you might think of as a permanent
collection of a set of CNXML modules. Instead, there is a document somewhere
on the website that defines the contents of a collection in the form of
pointers of some kind, and that document is used to organize a collection
when the time comes to generate an html file on the fly and send it to the

Here is the meta data for the html file that you receive when you land on
one of the modules.

    <meta http-equiv="Content-Type" content="application/xhtml+xml;
    <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7"/>
    <meta property="og:title" content="Units and Dimensional Analysis
for Blind Students"/>
    <meta property="og:type" content="article"/>
    <meta property="og:image" content="http://cnx.org/book_icon_cnx.png"/>
    <meta property="og:url"

    <meta property="og:site_name" content="Connexions"/>
    <meta property="fb:admins" content="100002202416123"/>
    <meta property="fb:page_id" content="81379287964"/>
    <meta property="og:description" content="The purpose of this
module is to explain units and dimensional analysis in a format that
is accessible to blind students."/>

As you can see, one of those items is the title of the collection, so in
effect, my title is being converted into metadata. The last item is a
sentence that I provide as a summary when I submit the module for

Christine, you wrote:

"1)  Regarding the Google and other similar search tools, if you type in
those same keywords, because of the fact that blind students is on the title
of the book, which appears at the beginning of each module, you will still
get the hits on Google regardless of whether the chapter titles contain it.
Thus, if they type something like trig and blindness and students they
should hit your trig page..."

As I mentioned to Ken earlier, there is no concept of a book in any
permanent sense. Instead, there is simply a document somewhere containing
pointers to CNXML files, that become a collection when someone is interested
in viewing the collection. The "title of the book" only exists at the
beginning of the html file for a given module when you ask to see that
module and the html file is generated on the fly for your benefit. Once that
html file is transmitted to you, it ceases to exist. In fact, it probably
never exists on the website in complete form. My guess is that each html
element is probably generated, transmitted to you, and then it ceases to
exist. Once again, however, I don't know what a search engine sees when it
visits the site and you may be entirely correct in your assessment of the

You also wrote:

"2)  I am not quite sure I get why the blindness comment is necessary for
your second argument. Although these are stand alone, the title of the book
and again the fact that the page states the book title should provide the
distinction you seek."

My earlier comments about the lack of a book apply here also.

Finally, you also wrote:

"As a speech software user, it gets a bit irritating having to hear blind
students at the end of every title."

And I do appreciate that and will honor your concern. I expect to be
updating many of the modules as time goes on to improve on the availability
of graphics. As I do that, I will delete the term "for Blind Students" from
each module when I need to revise it for some other purpose, and I will omit
that term from new modules as I publish them. Along the way, I will monitor
the position of the modules on the search engines to see if the position
suffers. If so, I will go back and reinstate the term where it has been
omitted or deleted.

Thanks to all of you for your comments.

Dick Baldwin

Richard G. Baldwin (Dick Baldwin)
Home of Baldwin's on-line Java Tutorials

Professor of Computer Information Technology
Austin Community College
(512) 223-4758
mailto:Baldwin at DickBaldwin.com

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