Friday, March 23, 2007

Top 10 Reasons to Major in Computing

I am marketing my own field of studying ;) What to know what ACM has to say about the $subject? Go right ahead!

Wednesday, March 14, 2007

XML Schema or RELAX NG (RNG)

We all know that the following limitations in DTD pushed for a new schema standard.

  1. DTD is expressed in its own language. We need to master another set of notations to work with DTD.
  2. We have no way to specify data types and data formats.

To overcome these issues, XML Schema (W3C standard) and RELAX NG (OASIS standard) were introduced. Both of them are based on XML itself.

There’s been a schema war among industry experts for a quite some time. You won’t disagree with me that XML schema enjoys a wider acceptance in the current software market (at least in the areas I am working on). But, which one is better, XML Schema or RELAX NG? I being a novice in this area, went on to browse through old archives at IETF XML USE newsgroup.

James Clark's post to promote RELAX NG is quite lengthy but philosophical. The follow up post by Eric Sedlar’s (Oracle Corporation) to defend XML Schema also has some valid points.

I agree that RNG is easy to understand with this excellent tutorial. At the same time, I was able to grab the concept behind XML Schema (which I currently use) quite easily. On the surface, it seems to me that the major difference lies in the style: while XML Schema categorize patterns into distinct components such as elements, attributes, complex/simple types, etc., RNG introduces generic patterns. I need to dive deep into both schemas in order to provide an objective and practical comparison. Wait..what about Schematron? I like the fact that it (schematron) does not impose any ordering of sibling elements (in contrary to XML Schema and RNG), which is quite valid and sufficient for data centric applications.

Friday, March 9, 2007

The World's Billionaires

Wow, according to Forbe's special report, there are over 900 billionires in the world! It's about 20% more than the previous year. Bill Gates continues to top the list for the 13th time. Indians top the list in Asia, with 36 billionires.

Although we see a rise in billionires, the question we need to ask is 'has the condition of the poor improved over the year?' I think the opposite has happened. One thing these people can do is to translate their success to more jobs, striking a balance between the rich and the poor.

Wednesday, March 7, 2007

Where is XML going?

I found the post by Kurt Cagle about current trends in XML fascinating..

Here's a summery I jotted down.
- rise of XML technologies - XSLT (XQuery and XForms are still a couple of years out from wide adoption) (and of couse job listings)
- XHTML becoming "standard" at least at the corporate level
- rise in demand for ontologists and RDF specialists (harnessing the ability to create metadata structures)
- transitional shift towards the declarative web architecture
- rise of JSON, E4X, Linq (unlikely that these languages will replace XML)
- XML Binding languages will be the next arena of development (and contention) - the ability to assign a behavior to an XML tag is profoundly useful, and provides both the bones of the declarative structures and the muscles of the imperative one, while keeping the presentation layer safely off to one side (AJAX).
- more commercial level XSLT2 transformations
- the interesting things being done in XML are increasingly occurring in the application and vertical markets
- HL7 in the health care field
- GML in the mapping and geographical location space
- XBRL or UBL in the business space
- while RDFa may have a fairly major hill to climb in terms of adoption, it will likely end up becoming integral to the semantic web fairly soon

Link: where is xml going?

Isn't this a good example about 'history repeats'?
The idea of declarative programming has been around for about half a century. Until I started to learn ML last year, I thought I knew fairly well about programming languages, which turned out to be wrong. Why is declarative programming in the form of Lisp, Haskell, ML, etc not commercially successful these days? The main reason might be that compared to imperative languages such as C, C++, Java, etc. it's harder to come up with a solution, at least initially or it may be that I am so used to imperative languages that I couldn't do away with it initially. Is there a marketing glitch attached to it as well (for not succeeding)? Having said all this, now we see a rise in XML declarative behavior bindings..isn't it a good example of 'history repeats'!

Transferring Terabytes of data from point A to point B

Read an interesting BBC news post. Chris DiBona, open source program manager at Google, talks about Google’s open source effort towards overcoming the problem of sending huge amount of data across network. The idea has been inspired by the work (Microsoft TerraServer) done by Jim Gray et al., the father of satellite mapping on the web (I am not sure if they have found Jim who went missing at sea).

Here’s the abstract of Microsoft TerraServer: a spatial data warehouse, published in Proceedings of the 2000 ACM SIGMOD international conference on Management of data.

Microsoft® TerraServer stores aerial, satellite, and topographic images of the earth in a SQL database available via the Internet. It is the world's largest online atlas, combining eight terabytes of image data from the United States Geological Survey (USGS) and SPIN-2. Internet browsers provide intuitive spatial and text interfaces to the data. Users need no special hardware, software, or knowledge to locate and browse imagery. This paper describes how terabytes of “Internet unfriendly” geo-spatial images were scrubbed and edited into hundreds of millions of “Internet friendly” image tiles and loaded into a SQL data warehouse. All meta-data and imagery are stored in the SQL database.

TerraServer demonstrates that general-purpose relational database technology can manage large scale image repositories, and shows that web browsers can be a good geo-spatial image presentation system.

Monday, March 5, 2007

How the Open Source Movement Has Changed Education: 10 Success Stories

This is related to my previous post. An interesting article highlighting major open source projects that have changed the shape of conventional education.


It's been nealy six years since MIT made most of its course materials free under the initiative OpenCourseWare (aka OCW). The current repository has more than 1500 courses to choose from.