The Psychology of Ontology Harmonization "My personal experience seems to suggest the exact opposite: higher the abstraction, lower the objectivity with which people can argue and, therefore, come to an agreement.
I've spoken to people that spent several years of their lives coming up with an ontology and their perception is that the complexity over time of these models to cover a particular domain saturates, does not continue to grow.
This is a basic, but vital assumption for this entire approach to work: if the ontologies grow linearely with the amount of information they can describe, the ontology creation/maintainance process simply won't scale globally."
Friday, April 30, 2004
Intellidimension's SWS
Semantic Web Search "Semantic Web Search is a search engine for the Semantic Web. Our site can be used by both people and computers to precisely locate and gather information published on the Semantic Web."
From the FAQ:
"...using our standard search engine interface you can just type a one or more of keywords describing the information you are trying to locate. This is no more complicated than a traditional Web search engine. However like a traditional Web search engine this can lead to a large number of irrelevant results. To narrow your search you can restrict it to the specific type of resource that you are trying to locate such as a person (FOAF Person) or news article (RSS Item). If your search is still producing a large number of irrelevant results than you can refine it further by specifying one or more specific property values that the resource must have."
From the FAQ:
"...using our standard search engine interface you can just type a one or more of keywords describing the information you are trying to locate. This is no more complicated than a traditional Web search engine. However like a traditional Web search engine this can lead to a large number of irrelevant results. To narrow your search you can restrict it to the specific type of resource that you are trying to locate such as a person (FOAF Person) or news article (RSS Item). If your search is still producing a large number of irrelevant results than you can refine it further by specifying one or more specific property values that the resource must have."
Browse the Semantic Web
How to Make a Semantic Web Browser "Two important architectural choices underlie the success of the Web: numerous, independently operated servers speak a common protocol, and a single type of client—the Web browser—provides point-and-click access to the content and services on these decentralized servers. However, because HTML marries content and presentation into a single representation, end users are often stuck with inappropriate choices made by the Web site designer of how to work with and view the content. RDF metadata on the Semantic Web does not have this limitation: users can access the underlying information and control how it is presented for themselves. This principle forms the basis for our Semantic Web browser—an end-user application that automatically locates metadata and assembles point-and-click interfaces from a combination of relevant information, ontological specifications, and presentation knowledge, all described in RDF and retrieved dynamically from the Semantic Web."
Some thoughts on RDF rendering had some ideas on visualizing the Semantic Web too.
Some thoughts on RDF rendering had some ideas on visualizing the Semantic Web too.
The Passion of RDF
"SemanticBible is ...an emerging exploration of new applications of markup and computational linguistic technology to the study of Scripture, with an emphasis on practical tools that encourage understanding and personal transformation."
See also: The Vision of a Semantic New Testament: "Just as important as avoiding commercial barriers to sharing is the requirement that SemANT support existing and emerging standards that enable use across the Internet. To this end, SemANT will build on the Semantic Web Activity of the World Wide Web Consortium (W3C), including XML as a syntactic standard for data interchange, and RDF for ontology-based representation, and DAML/OWL for additional semantic expressiveness.".
Another example of when your technology has matured like: PCs, CDROMs, Hypertext, the Web, etc.
See also: The Vision of a Semantic New Testament: "Just as important as avoiding commercial barriers to sharing is the requirement that SemANT support existing and emerging standards that enable use across the Internet. To this end, SemANT will build on the Semantic Web Activity of the World Wide Web Consortium (W3C), including XML as a syntactic standard for data interchange, and RDF for ontology-based representation, and DAML/OWL for additional semantic expressiveness.".
Another example of when your technology has matured like: PCs, CDROMs, Hypertext, the Web, etc.
XUL vs XAML
Mozilla, Gnome mull united front against Longhorn "So far, XUL has failed to catch on, and Microsoft questioned whether Mozilla's technology would do much to help Gnome ward off Longhorn's promised threat.
XAML, Microsoft warned, is more potent than XUL in its ability to reflect exactly what's in the operating system.
"XUL is not the multipurpose declarative language that Gnome probably wants," said Ed Kaim, product manager for the Windows developer platform. "People say that when all you've got is a hammer, everything looks like a nail. In the same way, people are trying to figure out how to crush XUL into an OS it really wasn't designed for. The browser is great for a lot of things, but when it comes to robust client side applications, it's not the best."
Another trick will be in reconciling XUL with Gnome's existing user interface technology.
"There are ways to marry them," said Bruce Perens, an open-source consultant who serves as executive director of the Desktop Linux Consortium, a marketing organization. "But it's very difficult to get the two teams working in the same direction. They both went on a several-year tour of technical creation where they sat down and created everything they needed to do GUI [graphical user interface] applications — and they didn't create the same thing. Now to get them together it would take some number of years to resolve the technical diversions.""
XAML, Microsoft warned, is more potent than XUL in its ability to reflect exactly what's in the operating system.
"XUL is not the multipurpose declarative language that Gnome probably wants," said Ed Kaim, product manager for the Windows developer platform. "People say that when all you've got is a hammer, everything looks like a nail. In the same way, people are trying to figure out how to crush XUL into an OS it really wasn't designed for. The browser is great for a lot of things, but when it comes to robust client side applications, it's not the best."
Another trick will be in reconciling XUL with Gnome's existing user interface technology.
"There are ways to marry them," said Bruce Perens, an open-source consultant who serves as executive director of the Desktop Linux Consortium, a marketing organization. "But it's very difficult to get the two teams working in the same direction. They both went on a several-year tour of technical creation where they sat down and created everything they needed to do GUI [graphical user interface] applications — and they didn't create the same thing. Now to get them together it would take some number of years to resolve the technical diversions.""
Query Use Cases
Query Languages Report "A report by AIFB and Sesame and Jeen Broekstra from the Sesame crew. The Authors know what they are talking about as they are SemWeb developers themselves.
Although a little self advertisement and some missing languages, its a good thing to read. If you need info about RDF Query languages, read it.
My previous demand about "optional joins in queries" is answered by SeRQL."
The report is an excellent example of the current features required from a query language. From what I can tell iTQL implements 11 of the 14. Some of the others are fairly trival to add support for (like the data type support).
Although a little self advertisement and some missing languages, its a good thing to read. If you need info about RDF Query languages, read it.
My previous demand about "optional joins in queries" is answered by SeRQL."
The report is an excellent example of the current features required from a query language. From what I can tell iTQL implements 11 of the 14. Some of the others are fairly trival to add support for (like the data type support).
Wednesday, April 28, 2004
Will the Semantic Web Scale?
Apparently, there's going to be a debate at WWW2004 about whether the Semantic Web will scale: "However, with only a few exceptions we noticed that current research and development is focusing on creating new technologies for facilitating the Semantic Web. Available technologies from other disciplines such as databases are rarely reused and adapted. Hence, most Semantic Web systems do not scale to Web-size problems.
Lately, several researchers doubted whether the Semantic Web idea will ever scale for numerous reasons technological [But03], theoretical [van02] and practical [MS03,Sow]. Dedicated workshops on that topic [CKDE03,VDC03] have been organized recently to promote research to improve scalability. We will pick up these three categories of doubt by organizing the panel in three parts discussing each aspect: theory, technology/implementation, and practise."
I'm not sure I agree, there are very few Semantic Web systems that don't reuse existing SQL databases - they just suck at storing triples. With Kowari, and I'm sure with other native stores, the data structures and techniques used are taken directly from databases. They mention "Is the semantic web hype?" (which I responded to) and a few others. Although, there's no links to syllogism, metacrap or gnomes. BTW, I'm still not sure why you'd want an XML version of OWL.
"Network round-trips are often considerably less costly than the time taken for a transactional database operation due to the need to forcibly log transactional operations which is very costly in terms of disk performance. i.e. network round-trips aren't always the performance bottleneck." From Martin Fowler's First Law of Distribution.
As long as you keep the Semantic Web like the Web there's no real reason why it shouldn't scale.
Lately, several researchers doubted whether the Semantic Web idea will ever scale for numerous reasons technological [But03], theoretical [van02] and practical [MS03,Sow]. Dedicated workshops on that topic [CKDE03,VDC03] have been organized recently to promote research to improve scalability. We will pick up these three categories of doubt by organizing the panel in three parts discussing each aspect: theory, technology/implementation, and practise."
I'm not sure I agree, there are very few Semantic Web systems that don't reuse existing SQL databases - they just suck at storing triples. With Kowari, and I'm sure with other native stores, the data structures and techniques used are taken directly from databases. They mention "Is the semantic web hype?" (which I responded to) and a few others. Although, there's no links to syllogism, metacrap or gnomes. BTW, I'm still not sure why you'd want an XML version of OWL.
"Network round-trips are often considerably less costly than the time taken for a transactional database operation due to the need to forcibly log transactional operations which is very costly in terms of disk performance. i.e. network round-trips aren't always the performance bottleneck." From Martin Fowler's First Law of Distribution.
As long as you keep the Semantic Web like the Web there's no real reason why it shouldn't scale.
Google Watching
What can't you find on Google? Vital statistics "Google is famous for being a confident, open company. Its clean, uncluttered search page is supposed to be a metaphor for the organisation behind it. But when you start asking questions about its technology, then the water rapidly becomes murky...One university presentation, for example, claimed that Google handled 150 million queries a day, and 1,000 per second at peak times...If the system is handling a peak load of 1,000 queries per second, he reasoned, that translates to a peak rate of 86.4 million queries per day - or perhaps 40 million queries per day...They also claim to have '4+ petabytes' of disk storage, and have let slip that each server is fitted with two 80 gigabyte hard drives. Now a petabyte is 10 to the power of 15 bytes, so if Google had only 10,000 servers, that would come to 400 Gb per server. So again the numbers don't add up."
Google Goes Public? The Rich Get Richer "People speculate. People dream. And if the numbers are to be believed, people will drool. The current prediction is that Google, if it decides to sell shares to investors this year, would probably end up with a market value of $20 billion to $25 billion by the end of its first day as a publicly traded company."
Google's Brin Talks on Gmail Future "It was interesting to me that you did finally hit on the word conversation. It seems to me that there's a synergy between the elements of the conversation in the RSS space and what you're doing in the e-mail space.
I think that's very true. Part of the things we've seen why blogs and RSS feeds are such a success is that you can actually read it—you don't have to stop, click back and forth, collect bits and pieces here and there—but it is all presented to you as one. "
Google Goes Public? The Rich Get Richer "People speculate. People dream. And if the numbers are to be believed, people will drool. The current prediction is that Google, if it decides to sell shares to investors this year, would probably end up with a market value of $20 billion to $25 billion by the end of its first day as a publicly traded company."
Google's Brin Talks on Gmail Future "It was interesting to me that you did finally hit on the word conversation. It seems to me that there's a synergy between the elements of the conversation in the RSS space and what you're doing in the e-mail space.
I think that's very true. Part of the things we've seen why blogs and RSS feeds are such a success is that you can actually read it—you don't have to stop, click back and forth, collect bits and pieces here and there—but it is all presented to you as one. "
Mozilla to Upgrade RDF
RDF module owner "With Benjamin Smedberg, Chase Tingley and Ben Goodger as peers, I took over the module ownership on RDF. We gonna push for both standards conformance (there are new specs out there since early 2004) and scriptability for remote web applications. This will include some serious whacking of the RDF API in Mozilla, as that is not ready for the web by a fair amount."
Tuesday, April 27, 2004
Ant is now more useful
ANT's finally a real build tool "And I can finaly call ANT a real build tool (and Maven can go play in its own cacca for all I care).
In a nutshell, the task lets you reference other build files. This means that you can create common centralized libraries of build files that other people can use on their own projects - all without copy and paste. And believe it or not, the semantics all make sense too. You can provide default tasks and properties, and the importer can override tasks and properties to customize behaviors on a case by case basis if it's required. The end result is that individual project build files are smaller and easier to understand, and common behavior can be achieved across an entire large system in a natural and non-cut-n-pasty manner (I don't know about you, but I always found pasties rather unnatural)."
Also new is macrodef: "Macrodef is a way to define a new Ant task in an Ant build itself. Macrodef allows you to define standard tasks that have attributes and elements given to them when they are called."
In a nutshell, the
Also new is macrodef: "Macrodef is a way to define a new Ant task in an Ant build itself. Macrodef allows you to define standard tasks that have attributes and elements given to them when they are called."
Paul's Blog
Paul is a guy that sits next to me at work and now is putting his development notes on a blog. So if you're interested in the inner-workings of Kowari take a look. I'll let people guess who DM, AM, and RMI are. :-)
Friday, April 23, 2004
Free Bits of Description Logic
DESCRIPTION LOGICS Includes a bunch of Postscript and PDF files (including the first couple of chapters of the DL Handbook).
Metaweb Graph Updated
New Version of My "Metaweb" Graph -- The Future of the Net "Many people have requested this graph and so I am posting my latest version of it. The Metaweb is the coming "intelligent Web" that is evolving from the convergence of the Web, Social Software and the Semantic Web. The Metaweb is starting to emerge as we shift from a Web focused on information to a Web focused on relationships between things --- what I call "The Relationship Web" or the "Relationship Revolution.""
Semaview Interview
What Is The Semantic Web? "The Semantic Web provides the foundation on which we can build more intelligent Internet applications. It will help everyone find, organize, collect, use and share information more easily."
"My company, Semaview has developed an application called eventSherpa. eventSherpa is making it simple to create and organize schedules and share them over the Internet. Our application automatically creates Semantic Web content transparently without the end user knowing it...Aside from reducing the complexity issue...I believe the largest challenge is convincing application developers to make their data available in semantic format. However it is "a chicken and egg problem" -- the more content available in a semantic format, the more applications that will be developed to take advantage of it; and vice versa."
"My company, Semaview has developed an application called eventSherpa. eventSherpa is making it simple to create and organize schedules and share them over the Internet. Our application automatically creates Semantic Web content transparently without the end user knowing it...Aside from reducing the complexity issue...I believe the largest challenge is convincing application developers to make their data available in semantic format. However it is "a chicken and egg problem" -- the more content available in a semantic format, the more applications that will be developed to take advantage of it; and vice versa."
Knobot
Reto was trying to get Kowari going. Hopefully it will get used for this project. Documentation gives download links and installation instructions.
From Danny Ayers: Knobot PlanetRDF Demo.
From Danny Ayers: Knobot PlanetRDF Demo.
XML 2004
The State of XML "As a software developer I feel increasingly unhappy with the development of a monolithic mass of technology building up, only reasonably accessible behind a Java or .NET API. In contrast, the REST model of composed, simple interactions seems more controllable and containable and you can still see the angle brackets in order to check that things are working. There is still plenty of work and experimentation to be done yet with the notion of more document-oriented web services."
"Consequently, even at the low level of operating systems vendors are seeing the need and advantages of implementing metadata storage and manipulation.
This is good. We have the tools to support this, whichever way you swing on the technology issues. RDF & OWL, Topic Maps, W3C XML Schema: all have the right machinery. Unfortunately that's not the biggest issue. The main problem is which terms, schemas, and ontologies to use. That's just not clear right now for most if not all metadata applications. At best, we'll get inconsistently classified information, which defeats the promise of interoperability. More typically, we'll end up with little tagged metadata and islands of de facto proprietary information."
"As an RDF fan, the realization of this truth causes me some pain. The way out is to stop thinking of RDF as an XML application, and look to easier syntaxes such as Turtle and N3."
"Consequently, even at the low level of operating systems vendors are seeing the need and advantages of implementing metadata storage and manipulation.
This is good. We have the tools to support this, whichever way you swing on the technology issues. RDF & OWL, Topic Maps, W3C XML Schema: all have the right machinery. Unfortunately that's not the biggest issue. The main problem is which terms, schemas, and ontologies to use. That's just not clear right now for most if not all metadata applications. At best, we'll get inconsistently classified information, which defeats the promise of interoperability. More typically, we'll end up with little tagged metadata and islands of de facto proprietary information."
"As an RDF fan, the realization of this truth causes me some pain. The way out is to stop thinking of RDF as an XML application, and look to easier syntaxes such as Turtle and N3."
Wednesday, April 21, 2004
Unix Job Ad
Unix Specialist "Ah, Unix. Its cheapass cousin, Linux, is what all Microsoft users turn to just as their sanity reaches a crossroads. Did you know that Microsoft Word stills spellchecks ‘Unix’ as ‘UNIX’? Man, how 80’s does that look? I can imagine something like that flickering on the screen of a computer you assembled yourself from a crystal radio kit."
"But the point of all that is, Unix is basically a sort of secret society where you either know it, or you don’t. And since most people just really can’t be bothered going through the agonies of learning it, it’s why we have jobs like this: “Unix Specialist”. Of course that means nothing, or at least it means about as much as “Car Specialist” or “Bread Specialist”. Bread Specialist? What the hell is that? What kind of bread? White, multigrain, mixed grain, wholemeal, sourdough? Sliced or unsliced? If sliced, sliced for sandwiches or for toast? Crusty or soft? No matter! Just eat your bread!"
"But the point of all that is, Unix is basically a sort of secret society where you either know it, or you don’t. And since most people just really can’t be bothered going through the agonies of learning it, it’s why we have jobs like this: “Unix Specialist”. Of course that means nothing, or at least it means about as much as “Car Specialist” or “Bread Specialist”. Bread Specialist? What the hell is that? What kind of bread? White, multigrain, mixed grain, wholemeal, sourdough? Sliced or unsliced? If sliced, sliced for sandwiches or for toast? Crusty or soft? No matter! Just eat your bread!"
RDF Engine
RDF Engine "The program RDFEngine was developed as a part of the master thesis of Guido Naudts. It was build on the example of Euler, the program of Jos De Roo. The original version was made with Haskell. It was then rewritten in Python. Purpose of the program was to implement a logic program for the Semantic Web initiative. Concerning compatibility the program is meant to be compatible with CWM in the sense that sources that work with CWM will also work with RDFEngine but not vice versa.(I like to do some experiments of my own (-: ). For input and output Notation 3 is used. See also the Notation 3 tutorial."
Tuesday, April 20, 2004
80/20 REST to SOAP
XMLEurope, Monday "The keynotes were by Jeff Barr of Amazon and Steven Pemberton from W3C. Interesting to hear some detail about the Amazon Web Services, including the 80/20 split between developer use of REST and SOAP interfaces to the Amazon catalogue, and the business case for making the catalogue available in machine-processible format: essentially the value is not in their catalogue per se, and they have a business model for third party sellers and affiliates, so WS access just makes this relationship easier. The output example he gave looked to me very close to RDF; with Amazon's XSLT service it could be transformed to it very easily I think."
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