Now Presented as a Semantic Component; Grows to 900+ Tools

Sweet Tools, AI3‘s listing of semantic Web and -related tools, has just been released with its 17th update. The listing now contains more than 900 tools, about a 10% increase over the last version. Significantly the listing is also now presented via its own semantic tool, the structSearch sComponent, which is one of the growing parts to Structured Dynamics‘ open semantic framework (OSF).

So, we invite you to go ahead and try out this new Flex/Flash version with its improved search and filtering! We’re pretty sure you’ll like it.

Summary of Major Changes

Sweet Tools now lists 907 919 tools, an increase of 72 84 (or 8.6 10.1%) over the prior version of 835 tools. The most notable trend is the continued increase in capabilities and professionalism of (some of) the new tools.

This new release of Sweet Tools — available for direct play and shown in the screenshot to the right — is the first to be presented via Structured Dynamics’ Flex-based semantic component technology. The system has greatly improved search and filtering capabilities; it also shares the superior dataset management and import/export capabilities of its structWSF brethren.

As a result, moving forward, Sweet Tools updates will now be added on a more regular basis, reducing the big burps that past releases have tended to follow. We will also see much expanded functionality over time as other pieces of the structWSF and sComponents stack get integrated and showcased using this dataset.

This release is the first in WordPress, and shows the broad capabilities of the OSF stack to be embedded in a variety of CMS or standalone systems. We have provided some updates on Structured Dynamics’ OSF TechWiki for how to modify, embed and customize these components with various Flex development frameworks (see one, two or three), such as Flash Builder or FlashDevelop.

We should mention that the OSF code group is also seeing external parties exposing these capabilities via JavaScript deployments as well. This recent release expands on the conStruct version with its capabilities described in a post about a year ago.

Retiring the Exhibit Version

However, this release does mark the retirement of the very fine Exhibit version of Sweet Tools (an archive version will be kept available until it gets too long in the tooth). I was one of the first to install a commercial Exhibit system, and the first to do so on WordPress, as I described in an article more than four years ago.

Exhibit has worked great and without a hitch, and through a couple of upgrades. It still has (I think) a superior faceting system and sorting capabiities to what we presently offer with our own sComponent alternative. However, the Exhibit version is really a display technology alone, and offers no search, access control or underlying data management capabilities (such as CRUD), all of which are integral to our current system. It is also not grounded in RDF or semantic technologies, though it does have good structural genes. And, Sweet Tools has about reached the limits of the size of datasets Exhibit can handle efficiently.

Exhibit has set a high bar for usability and lightweight design. As we move in a different direction, I’d like again to publicly thank David Huynh, Exhibit’s developer, and the MIT Simile program for when he was there, for putting forward one of the seminal structured data tools of the past five years.

Updated Statistics

The updated Sweet Tools listing now includes nearly 50 different tools categories. The most prevalent categories are browser tools (RDF, OWL), information extraction, ontology tools, parsers or converters, and general RDF tools. The relative share by category is shown in this diagram (click to expand):

Since the last listing, the fastest growing categories have been utilities (general and RDF) and visualization. Linked data listings have also grown by 200%, but are still a relatively small percentage of the total.

These values should be taken with a couple of grains of salt. First, not all of these additions are organic or new releases. Some are the result of our own tools efforts and investigations, which can often surface prior overlooked tools. Also, even with this large number of application categories, many tools defy characterization, and can reside in multiple categories at once or are even pointing to new ones. So, the splits are illustrative, but not defining.

General language percentages have been keeping pretty constant over the past couple of years. Java remains the leading language with nearly half of all applications, a percentage it has kept steady for four years. PHP continues to grow in popularity, and actually increased the largest percentage amount of any language over this past census. The current language splits are shown in the next diagram (click to expand):

C/C++ and C# have really not grown at all over the past year. Again, however, for the reasons noted, these trends should be interpreted with care.

Dogfood Never Tasted So Good

Tools development is hard and the open source nature of today’s development tends to require a certain critical mass of developer interest and commitment. There are some notable tools that have much use and focus and are clearly professional and industrial grade. Yet, unfortunately, too many of the tools on the Sweet Tools listing are either proofs-of-concept, academic demos, or largely abandoned because of lack of interest by the original developer, the community or the market as a whole.

There is a common statement within the community about how important it is for developers to “eat their own dogfood.” On the face of it, this makes some sense since it conveys a commitment to use and test applications as they are developed.

But looked at more closely, this sentiment carries with it a troublesome reflection of the state of (many) tools within the semantic Web: too much kibble that is neither attractive nor tasty. It is probably time to keep the dogfood in the closet and focus on well-cooked and attractive fare.

We at Structured Dynamics are not trying to hold ourselves up as exemplars or the best chefs of tasty food. We do, however, have a commitment to produce fare that is well prepared and professional. Let’s stop with the dogfood and get on with serving nutritious and balanced fare to the marketplace.

Reasons for and Implications from Innovation Moving to Consumers

Today, the headlines and buzz for information technologies centers on smartphones, social networks, cloud computing, tablets and everything Internet. Very little is now discussed about IT in the enterprise. This declining trend began about 15 years ago, and has been accelerating over time. Letting the air out of the enterprise IT balloon has some profound reasons and implications. It also has some lessons and guidance related to semantic approaches and technologies and their adoption by enterprises.

A Brief Look at Sixty Years of Enterprise IT

One can probably clock the start of enterprise information technology (IT) to the first use of mainframe computers in the early 1950s [1], or sixty years ago. The earliest mainframes were huge and expensive machines that required their own specially air-conditioned rooms because of the heat they generated. The first use of “information technology” as a term occurred in a Harvard Business Review article from 1958 [2].

Until the late 1960s computers were usually supplied under lease, and were not purchased [3]. Service and all software were generally bundled into the lease amount without separate charge and with source code provided. Then, in 1969, IBM led an industry change by starting to charge separately for (mainframe) software and services, and ceasing to supply source code [3]. At about the same time integrated circuits enabled computer sizes to be reduced, with the minicomputers such as from DEC causing a marked expansion in number of potential customers. Enterprise apps became a huge business, with software licensing and maintenance fees achieving a peak of 70% of IT vendor total revenues by the mid-1990s [4]. However, since that peak, enterprise software as a portion of vendor revenues has been steadily eroding.

One of the earliest enterprise applications was in transaction systems and their underlying database management software. The relational database management system (RDBMS) was initially developed at IBM. Oracle, based on early work for the CIA in the late 1970s and its innovation to write in the C programming language, was able to port the RDBMS to multiple operating systems. These efforts, along with those of other notable vendors (most of which like Informix no longer exist), led to the RDBMS becoming more or less the de facto standard for data management within the enterprise by the 1980s. Today Oracle is the largest supplier of RDBMS software globally, and other earlier database system designs such as network databases or object databases fell out of favor [5].

In 1975, the Altair 8800 was introduced to electronics hobbyists as the first microcomputer, followed then by Apple II and the IBM PC in 1981, among others. Rapidly a slew of new applications became available to the individual, including spreadsheets, small databases, graphics programs and word processors. These apps were a boon to individual productivity and the IBM PC in particular brought credibility and acceptance within the enterprise (along with the growth of Microsoft). Novell and local area networks also pointed the way to a more distributed computing future. By the late 1980s virtually every knowledge worker within enterprises had some degree of computer literacy.

The apogee for enterprise software and apps occurred in the 1990s, with whole classes of new applications (most denoted by three-letter acronyms) such as enterprise resource planning (ERP), business intelligence (BI), customer relationship management (CRM), enterprise information systems (EIS) and the like coming to the fore. These systems also began as proprietary software, which resulted in the “stovepiping” or creating of information silos. In reaction and with great market acceptance, vendors such as SAP arose to provide comprehensive, enterprise-wide solutions, though often at high cost and with significant failure rates.

More significantly, the 1990s also saw the innovation of the World Wide Web with its basis in hypertext links on the Internet. Greatly facilitated by the Mosaic Web browser, the basis of the commercial Netscape browser, and the HTML markup language and HTTP transport protocol, millions began experiencing the benefit of creating Web pages and interconnecting. By the mid-1990s, enterprises were on the Web in force, bringing with them larger content volumes, dynamic databases and enterprise portals. The ability for anyone to become a publisher led to a focus and attention on the new medium that led to still further innovations in e-commerce and online advertising. New languages and uses of Web pages and applications emerged, creating a convergence of design, media, content and interactivity. Venture capital and new startups with valuations independent of revenues led to a frenzy of hype and eventually the dot com crash of 2000.

The growth companies of the past 15 years have not had the traditional focus on enterprises, but on the use and development of the Web. From search (Google) to social interactions (Facebook) to media and video (Flickr, YouTube) and to information (Wikipedia), the engines of growth have shifted away from the enterprise.

Meanwhile, the challenges of data integration and interoperability that were such a keen focus going back to initial enterprise computerization remain. Now, however, these challenges are even greater, as we see images, documents (unstructured data) and Web pages, markup and metadata (semi-structured data) become first-class information citizens. What was a challenge in integrating structured data in the 1980s and 1990s via data warehousing, has now become positively daunting for the enterprise with respect to scale and scope.

The paradox is that as these enterprise needs increased, the attractiveness of the enterprise from an IT perspective has greatly decreased. It is these factors we discuss below, with an eye to how Web architecture, design and opportunities may offer a new path through the maze of enterprise information interoperability.

The Current Landscape

Since 1995 the Gartner Group has been producing its annual Hype Cycle [6]. The clientele for this research is the enterprise, so Gartner’s presentation of what’s hot and what’s hype and what is being adopted is a good proxy for the IT state of affairs in enterprises. These graphs are reproduced below since 2006 (click to expand). Note how many of the items shown are not very specific to the enterprise:

References to architectures and content processing and related topics were somewhat prevalent in 2006, but have disappeared most recently. In comparison to the innovations noted under the History discussion, it appears that the items on Gartner’s radar are more related to consumer applications and uses. We no longer see whole new categories of enterprise-related apps or enterprise architectures.

The kinds of innovations that are being discussed as important to enterprises in the coming year [7,8] tend to mostly leverage existing innovations in other areas or to wrinkle existing approaches. One report from Constellation Research, for example, lists the five core disruptive technologies of social, mobile, cloud, analytics and unified communications [7]. Only analytics could be described as enterprise focused or driven.

And, even in analytics, the kinds of things being promoted are self-service reporting or analysis [8]. In essence, these opportunities represent the application of Web 2.0 techniques to bring reporting or analysis directly to the analyst. Though important and long overdue, such innovations are more derivative than fundamental.

Master data management (MDM) is another touted area. But, to read analyst’s predictions in these areas, it feels like one has stepped into a time warp of technologies and options from a decade ago. When has XML felt like an innovation?

Of course, there is a whole industry of analysts that makes their living prognosticating to enterprises about what to expect from information technologies and how to adopt and embrace them. The general observations — across the board — seem to center on items such as smartphones and mobile, moving to the cloud for software or platforms (SaaS, PaaS), and collaboration and social networks. As I note below, there is nothing inherently wrong or unexciting per se about these trends. But, what does appear true is that the locus of innovation has shifted from the enterprise to consumers or the Internet.

Seven Reasons for a Shift in Innovation

The shift in innovation away from the enterprise has been structural, not cyclical. That means that very fundamental forces are at work to cause this change in innovation focus. It does not mean that innovation has permanently shifted away from the enterprise (organizations), but that some form of countervailing structural changes would need to occur to see a return to the IT focus on the enterprise from prior decades.

I think we can point to seven structural reasons for this shift, many of which interact with one another. While all of them are bringing benefits (some yet to be foreseen) to the enterprise, and therefore are to be lauded, they are not strictly geared to address specific enterprise challenges.

#1: The Internet

As pundits say, “The Internet changes everything” [9]. For the reasons noted under the history above, the most important cause for the shift in innovation away from the enterprise has been the Internet.

One aspect that is quite interesting is the use of Internet-based technologies to provide “outsourced” enterprise applications hosted on Web servers. Such “cloud computing” leverages the technologies and protocols inherent to the Internet. It shifts hosting, maintenance and upgrade responsibilities for conventional apps to remote providers. Initially, of course, this simply shifts locus and responsibility from in-house to a virtual party. But, it is also the case that such changes will also promote more subtle shifts in collaboration and interaction possibilities. There is also the fact that quick upgrades of underlying infrastructure and application software can also occur.

The implications for existing enterprise IT staff, traditional providers, and licensing and maintenance approaches are profound. The Internet and cloud computing will perhaps have a greater effect on governance, staffing and management than application functionality per se.

#2: Consumer Innovations

The captivating IT-related innovations at present are mobile (smartphones) and their apps, tablets and e-book readers, Internet TV and video, and social networks of a variety of stripes. Somewhat like the phenomenon of when personal computers first appeared, many of these consumer innovations have applicability to the enterprise, though only as a side effect.

It is perhaps instructive to look back at the adoption of PCs in the enterprise to understand the possible effect of these new consumer innovations. Central IT was never able to control and manage the proliferation of personal computers, and only began to understand years later what benefits and new governance challenges they brought. Enterprise leaders will understand how to embrace and extend today’s new consumer technologies for the enterprise’s benefits; laggards will resist to no avail.

The ubiquity of computing will be enormously impactful on the enterprise. The understanding of what makes sense to do on a mobile basis with a small screen and what belongs on the desk or in the office is merely a glimmer in the current conversation. However, in the end, like most of the other innovations noted in this analysis, the enterprise will largely be a reactive player to these innovations. Yes, the implications will be profound, but their inherent basis are not grounded in unique enterprise challenges. Nonetheless, adapting to them and changing business practice will be critical to asserting enterprise leadership.

#3: Open Source

Ten years ago open source was largely dismissed in the enterprise. About five years ago VCs and others began funding new commercial open source ventures, even while there were still rear guard arguments from enterprises resisting open source. Meanwhile, as the figure to the right shows, open source projects were growing exponentially [10].

The shift to open source in the enterprise, still ongoing, has been rapid. Within 5 years, more than 50% of enterprise software will be open source [11] . According to an article in Fortune magazine last year [12], a Forrester Research survey found that 48% of enterprise respondents were using open source operating systems, and 57% were using open source code. A similar Accenture survey of 300 large public and private companies found that half are committed to open source software, with 38% saying they would begin using open-source software for “mission-critical” applications over the next 12 months.

There are likely many reasons for this shift, including the Internet itself and its basis in open source. Many of the most successful companies of the past 15 years including Amazon, Google, Facebook, and virtually any large Web site has shown excellent performance and scalability building their IT infrastructure around open source foundations. Most of the large, existing enterprise IT vendors, notably including IBM, Oracle, Nokia, Intel, Sun (prior to Oracle), Citrix, Novell (just acquired by Attachmate) and SAP have bought open source providers or have visible support for open source initiatives. Even two of the most vocal proprietary source proponents of the past — HP and Microsoft — have begun to make moves toward open source.

The age of proprietary software based on proprietary standards is dead. The monopoly rents formerly associated with unique, proprietary platforms and large-scale enterprise apps are over. Even where software remains proprietary, it is embracing open standards for data interchange and APIs. Traditional enterprise apps such as content management, business intelligence and ETL, among all others, are being penetrated by commercial open source offerings (as examples, Alfresco, Pentaho and Talend, respectively). The shift to services and new business models appears to be an inexorable force.

Declining profit margins, matched with the relatively high cost of marketing and sales to enterprises, means attention and focus have been shifting away from the enterprise. And with these shifts in focus has come a reduction in enterprise-focused innovation.

#4: Slow Development Cycles in Enterprise

It is not unusual to find deployed systems within enterprises as old as thirty years [13]. So long as they work reasonably well, systems once installed — along with their data — tend to remain in operation until their platforms or functionality become totally obsolete. This leads to rather lengthy turnover cycles, and slow development cycles.

Slow cycles in themselves slow innovation. But slow development cycles are also a disincentive to attract the most capable developers. When development tends to focus on maintenance and scripts and more routines of the same nature, the best developers tend to migrate elsewhere (see next).

Another aspect of slow development cycles is the imperative for new enterprise IT to relate to and accommodate legacy systems — again, including legacy data. This consideration is the source of one of the negative implications of a shift away from innovation in the enterprise: the orphaning of existing information assets.

#5: What’s Hot: Developers

Arguably the emphasis on consumer and Internet technologies means that is where the best developers gravitate. Developing apps for smartphones or working at one of the cool Internet companies or joining a passionate community of open source developers is now attracting the best developers. Open source and Web-based systems also lead to faster development cycles. The very best developers are often the founders of the next generation startups and Web and software companies [14].

While, of course, huge numbers of computer programmers and IT specialists are hired by enterprises each year, the motivations tend to be higher pay, better benefits and more job security. The nature of the work and the bureaucracy and routine of many IT functions require such compensation. And, because of the other shifts noted elsewhere, even the software startups that are able to attract the most innovative developers no longer tend to develop for enterprise purposes.

Computer science students have been declining in industrialized countries for some time and that is the category of slowest growth in IT [14]. Meanwhile, existing IT personnel often have expertise in older legacy systems or have been focused on bug fixes and more prosaic tasks like report writing. Narrow job descriptions and work activities also keep many existing IT personnel from getting exposed to or learning about new trends or innovations, such as the semantic Web.

Declining numbers of new talent, plus declining interest by that talent, combined with (often) narrow and legacy expertise of existing talent, creates a disappointing storm of energy and innovation to address enterprise IT challenges. Enterprises have it within their power to create more exciting career opportunities to overcome these limitations, but unfortunately IT management often also appears challenged to get on top of these structural forces.

#6: What’s Hot: Startups

Open source and Internet-based systems have reduced the capital necessary for a new startup by an order of magnitude or so over the past decade. It is now quite possible to get a new startup up and running for tens to hundreds of thousands of dollars, as opposed to the millions of years past. This is leading to more startups, more startups per innovator, and quicker startup and abandonment cycles. Ideas can be tried quickly and more easily thrown away [15].

These dynamics are acting to accelerate overall development cycles and to cause a shift in funding structures and funding amounts by VCs and angels. The kind of market and sales development typical for many enterprise sales does not fit well within these dynamics and is a countervailing force for more capital when all trends point the other way.

In short, all of this is saying that money goes to where the returns are, and returns are not of the same basis as decades past in the enterprise sector. Again, this means a hollowing out of innovation for enterprises.

#7: Declining Software Rents and Consolidation

As an earlier reference noted [4], software revenues as a percent of IT vendor revenues peaked in about the mid-1990s. As profitability for these entities began to decline, so did the overall attractiveness of the sector.

As the next chart shows, coincident with the peak in profitability was the onset of a consolidation trend in the enterprise IT vendor sector [16]. The chart below shows that three of the largest IT vendors today — Oracle, IBM and HP — began an acquisition spree in the mid-1990s that has continued until just recently, as many of the existing major players have already been acquired:

Notable acquisitions over this period include: Oracle — PeopleSoft, Siebel Systems, MySQL, Hyperion, BEA and Sun; HP — EDS, 3Com, VeriFone, Compaq, Palm and Mercury Interactive; IBM — Lotus, Rational, Informix, Ascential, FileNet, Cognos and SPSS. Published acquisition costs exceeded $130 billion, mostly for the larger deals. But terms for 75% of the 262 transactions were not disclosed [16]. The total value of these consolidations likely approaches $200 billion to $300 billion.

Clearly, the market is now favoring large players with large service components. This consolidation trend does belie one early criticism of open source v proprietary software: proprietary software is likely to be better supported. In theory this might be true, but vanishing suppliers does not bode well for support either. Over time, we may likely see successful open source projects showing greater longevity than many IT vendors.

Positive Implications from the Decline

This discussion is not a boo-hoo because the heyday of enterprise IT innovation is past. Much of that innovation was expensive, often failed to achieve successful adoption, and promoted walled gardens and silos. As someone who ran companies directly involved in enterprise software sales, I personally do not miss the meetings, the travel, the suits and the 18-month sales cycles.

The enterprise has gained much from outside innovation in the past, from the personal computer to LANs and browsers and the Internet. To be sure, what we are now seeing with mobile phones has more computing power than the original Space Shuttle [17], and continued mashup and social engagement innovations will have unforeseen and manifest benefits for enterprises. I think this is unalloyed goodness.

We can also see innovations based on the Internet such as the semantic Web and its languages and standards to promote interoperability. Breaking these barriers is critically needed by enterprises of the future. Data models such as RDF [18] and open world mindsets that better accommodate uncertainty and breadth of information [19] can only be seen as positive. The leverage that will come from these non-enterprise innovations may in the end prove to be as important as the enterprise-specific innovations of the past.

Negative Implications from the Decline

Yet a shift to Internet and consumer IT innovation leaves some implications. These concerns have to do with the unique demands and needs of enterprises. One negative implication is that a diminishing supplier base may not lead to actual deployments that are enterprise-ready or -responsive.

The first concern relates to quality and operational integrity. There is an immense gulf between ISO 9000 or Six Sigma and, for example, the “good enough” of standard search results on the Web. Consumer apps do not impose the same thresholds for quality as demanded by paying bosses or paying customers. This is not a value judgment; simply a reality. I see it reflected in the quality of tools and code for many new innovations today on the Web.

Proofs-of-concept and “cool” demos work well for academic theses or basic intros to new concepts. The 20% that gets you 80% goes a long way to point the way to new innovation; but the 80% to get to the last 20% is where enterprises bet their money. Unfortunately, in too many instances, that gap is not being filled. The last 20% is hard work, often boring, and certainly not as exciting as the next Big Thing. And, as the trends above try to explicate, there are also diminishing rewards for living in that territory.

A similar and second concern pervades data interoperability. Data interoperability has been the central challenge of enterprise IT for at least three decades. As soon as we were able to interconnect systems and bridge differences in operating systems and data schema, the Holy Grail has been breaking information barriers and silos. The initial attempts with proprietary data warehouses or enterprise-wide ERP systems were wrongly trying to apply closed solutions to inherently open problems. But, now, finally when we have the open approaches and standards in hand for bridging these gaps, the attractiveness of doing so for the enterprise seems to have vanished.

For example, we see demos, tools and algorithms being published all over the place that show promising advances or improvements in the semantic Web or linked data (among other areas; see [20]). Some of these automated techniques sound wonderful, but real systems require the hard slog of review and manual approval. Quality matters. If Technique A, say, shows an improvement over Technique B of 5%, that is worth touting. But even at 98% percent accuracy, we will still find 20,000 errors in a population of 1 million items. Such errors will simply not work in having trains run on time, seats be available on airplanes, or inventory get to their required destinations.

What can work from the standpoint of linkage or interoperability on the Web according to consumer standards will simply not fly for many enterprises. But, where are the rewards for tackling that hard slog?

Another concern is security and differential access. Open Web systems, bless their hearts, do not impose the same access and need to know restrictions as information systems within enterprises. If we are to adopt Web-based approaches to the next-generation enterprise — a position we strongly advocate — then we are also going to need to figure out how to marry these two world views. Again, there appears to be an effort-reward mismatch here.

What Lessons Might be Drawn?

These observations are not meant to be a polemic, but a statement of more-or-less current circumstances. Since its widescale adoption, the major challenge — and opportunity — of enterprise IT has been how to leverage the value within the enterprise’s existing digital information assets. That challenge is augmented today with the availability of literally a whole world of external digital knowledge. Yet, the energy and emphasis for innovation to address these challenges has seemingly shifted to consumers and away from the enterprise.

Economics abhors a vacuum. I think two responses may be likely to this circumstance. The first is that new vendors will emerge to address these gaps, but with different cost structures and business models. I’d like to think my own firm, Structured Dynamics, is one of these entities. How we are addressing this opportunity and differences in our business model we will discuss at a later time. In any case, any such new player will need to take account of some of the structural changes noted above.

Another response can come from enterprises themselves, using and working the same forces of change noted earlier. Via collaboration and open source, enterprises can band together to contribute resources, expertise and people to develop open source infrastructures and standards to address the challenges of interoperability. We already see exemplars of such responses in somewhat related areas via initiatives such as Eclipse, Apache, W3C, OASIS and others. By leveraging the same tools of collaboration and open data and systems and the Internet, enterprises can band together and ensure their own self-interests are being addressed.

One advantage of this open, collaborative approach is that it is consistent with the current innovation trends in IT. But the real advantage is that it works and is needed. Without it, it is unclear how the enterprise IT challenge — especially in data interoperability — will be met.

Objective is to Tackle the ‘Semantics’ Gap in the Semantic Web

I’m pleased to announce that our company, Structured Dynamics, has formed a strategic partnership with Ontotext, a leading semantic technology company for the past 10 years.

Ontotext is the developer of OWLIM, a highly scalable semantic database engine, and KIM, a popular semantic annotation and search platform. Its FactForge and LinkedLifeData services provide the largest curated and interoperable linked data platforms over which inferencing and reasoning may be applied. Some of Ontotext’s major clients include AstraZeneca, BBC and Korea Telecom. Major professional services include its own technologies, plus text mining and semantic annotation. Ontotext has notable and longstanding technical partnerships, such as with the GATE team and many of the other leading technologies and companies in the semantic Web space. We are very pleased to join forces with them.

Semantic ‘Gap’ is Basis of Partnership

Our partnership was formed to address some of the key semantic ‘gaps’ in the semantic Web. The partnership will focus on development of the next generation of the UMBEL and PROTON ontologies, as well as tools and applications based on them.

Volumes of linked data on the Web are growing. This growth is exposing three key weaknesses:

1. inadequate semantics for how to link disparate information together that recognizes inherently different contexts and viewpoints and (often) approximate mappings
2. misapplication of many linking predicates, such as owl:sameAs, and
3. a lack of coherent reference concepts by which to aggregate and organize this linkable content.

Thanks to the efforts of the W3C (World Wide Web Consortium), we now have the techniques, languages and standards to deliver the “web” portion of the semantic Web. But, the practical “semantics” for actually effecting the semantic Web have heretofore been lacking. Early experience with linked data has exposed many poor practices. The lack of approximate linking predicates and reference concepts undercuts our ability to achieve meaningful semantic interoperability.

In forming our partnership, Ontotext and SD will shine attention on this semantics “gap”. We will also be aggressively seeking additional partners and players to join with us on this challenge. My recent outreach to DCMI (the Dublin Core Metadata Initiative) is one example of this commitment; we will be talking with others in the coming weeks.

Linked data and the prospects of the semantic Web are at a critical juncture. While we have seen much growth in the release of linked data, we are still not seeing much uptake (other than some curated pockets). Linkages between datasets are still disappointingly low, and quality of linkages is an issue. The time has come to stop simply shoveling more triples over the fence.

Building Blocks

The combination of UMBEL and PROTON offers a powerful blend to address these weaknesses. Our partnership will first provide a logical mapping and consolidated framework based on the two core ontologies. These will be made available as standard ontologies and via open source semantic annotation tools.

UMBEL (Upper Mapping and Binding Exchange Layer) is both a vocabulary for building domain ontologies and a framework of more than 20,000 reference concepts. The UMBEL reference ontology is used to tag information and map existing schema in order to help link content and promote interoperability. UMBEL’s reference concepts and structure are a direct subset extraction of the Cyc knowledge base.

The PROTON ontology (PROTo ONtology) is a basic upper-level ontology that contains about 300 classes and 100 properties, providing coverage of the general concepts necessary for a wide range of tasks, including semantic annotation, indexing, and retrieval of documents. It is domain independent with coverage suitable to encompass any domain or named entity.

This consolidated framework will then be applied to organize and provide a coherent categorization of the Wikipedia online encyclopedia. One expression of this result will be a new version of Ontotext’s FactForge, already the largest and best performing reasoning engine leveraging linked data. This new version will allow easy access to the most central Linking Open Data (LOD) datasets such as DBpedia, Freebase, and Geonames, through the vocabularies of UMBEL and PROTON. Additional applications in linked data mining and general tagging of standard Web content are also contemplated by the partnership.

Ontotext’s proven reasoning technologies and ability to host extremely large knowledge bases with great performance are tremendous boons to the next iteration of UMBEL. We have been seeking large-scale coherency testing of UMBEL for some time and Ontotext is the perfect answer.

Ontotext’s CEO, Atanas Kiryakov, indicated their interest in UMBEL stemmed from what they saw as some stumbling blocks with linked data while developing FactForge. “The growth and maturation of linked data will require credible ways to orient and annotate the data,” said Kiryakov. “UMBEL is the right scope of comprehensiveness and size to use as one foundation for this,” he said. Ontotext is also the original developer and current maintainer of PROTON, which will also contribute in this role.

What is to Come?

The efforts of the partnership will first be seen with release of UMBEL v. 0.80 in the next couple of weeks. This update revises many aspects of the ontology based on two years of applied experience and updates it to OWL 2. Then, this basis will be used for broader mappings and linkages to Wikipedia. Those next mappings are earmarked for UMBEL version 1.00, slated for release by the end of the year. All of these planned efforts will be released as open source.

Among other intended uses, PROTON, UMBEL and FactForge form a layered reference data structure that will be used for data integration within the European Union research project RENDER. The large-scale RENDER project aims to integrate diverse methods in the ways Web information is selected, ranked, aggregated, presented and used.

Beyond that, further relationships and partnerships are being actively sought with players serious about interoperable, high-quality data on the semantic Web. We welcome inquiries or outreach.

Shifting the Center of Gravity to the OWL API, Web Services

Previous installments in this series have listed existing ontology tools, overviewed development methodologies, and proposed a new approach to building lightweight, domain ontologies [1]. For the latter to be successful, a new generation in ontology development tools is needed. This post provides an explication of the landscape under which this new generation of tools is occurring.

Ontologies supply the structure for relating information to other information in the semantic Web or the linked data realm. Because of this structural role, ontologies are pivotal to the coherence and interoperability of interconnected data.

We are now concluding the first decade of ontology development tools, especially those geared to the semantic Web and its associated languages of RDFS and OWL. Last year we also saw the release of the major update to the OWL 2 language, with its shift to more expressiveness and a variety of profiles. The upcoming next generation of ontology tools now must also shift.

The current imperative is to shift away from ontology engineering by a priesthood to pragmatic daily use and maintenance by domain practitioners. Market growth demands simpler, task-focused tools with intuitive interfaces. For this change to occur, the general tools architecture needs to shift its center of gravity from IDEs and comprehensive toolkits to APIs and Web services. Not surprisingly, this same shift is what has been occurring across all areas of software.

Methodology Reprise: The Nature of the Landscape

In the previous installment of this series, we presented a new methodological approach to ontology development, geared to lightweight, domain ontologies. One aspect of that design was to separate the operational workflow into two pathways:

• Instances, and their descriptive characteristics, and
• Conceptual relationships, or ontologies.

The ontology build methodology concentrated on the upper half of this diagram (blue, with yellow lead-ins and outcomes) with the various steps overviewed in that installment [2]:

Figure 1. Flowchart of Ontology Development Methodology (click to expand)

The methodology captured in this diagram embraces many different emphases from current practice:  re-use of existing structure and information assets; conscious split between instance data (ABox) and the conceptual structure (TBox) [3]; incremental design; coherency and other integrity testing; and explicit feedback for scope extension and growth. The methodology also embraces some complementary utility ontologies that also reflect the design of ontology-driven apps [4].

These are notable changes in emphasis. But they are not the most important one. The most important change is the tools landscape to implement this methodology. This landscape needs to shift to pragmatic daily use and maintenance by domain practitioners. That requires simpler and more task-oriented tools. And that change in tooling needs a still more fundamental shift in tools architecture and design.

A Legacy of Excellent First Generation Tools

In many places throughout this series I use the term “inadequate” to describe the current state of ontology development tools. This characterization is not a criticism of first-generation tools per se. Rather, it is a reflection of their inadequacy to fulfill the realities of the new tooling landscape argued in this series. The fact remains, as initial generation tools, that many of the existing tools are quite remarkable and will play central roles (mostly for the professional ontologist or developer) moving forward.

At the risk of overlooking some important players, let’s trace the (partial) legacy of some of the more pivotal tools in today’s environment.

As early as a decade ago the ontology standards languages were still in flux and the tools basis was similarly immature. Frame logic, description logics, common logic and many others were competing at that time for primacy and visibility. Most ontology tools at that time such as Protégé [5], OntoEdit [6], or OilEd [7] were based on F-logic or the predecessor to OWL, DAML+Oil. But the OWL language was under development by the W3C and in anticipation of its formal release the tools environment was also evolving to meet it. Swoop [8], for example, was one of the first dedicated OWL browsers. A Protégé plug-in for OWL was also developed by Holger Knublauch [9]. In parallel, the OWL group at the University of Manchester also introduced the OWL API [10].

With the formal release of OWL 1.0 in 2004, ontology tools continued to migrate to the language. Protégé, up through the version 3x series, became a popular open source system with many visualization and OWL-related plug-ins. Knublauch joined TopQuadrant and brought his OWL experience to TopBraid Composer, which shifted to the Eclipse IDE platform and leveraged the Jena API [9,11]. In Europe, the NeON (Networked Ontologies) project started in 2006 and by 2008 had an Eclipse-based OWL platform using the OWL API with key language processing capabilities through GATE [12].

Most recently, Protégé and NeON in open source, and TopBraid Composer on the commercial side, have likely had the largest market share of the comprehensive ontology toolkits. So far, with the release of OWL 2 in late 2009, only Protégé in version 4 and the TwoUse Toolkit have yet fully embraced all aspects of the new specification, doing so by intimately linking with the new OWL API (version 3x has full OWL 2 support) [13]. However, most leading reasoners now support OWL 2 and products such as TopBraid Composer and Ontotext’s OWLIM support OWL 2 RL as well [14].

The evolution of Protégé to version 4 (OWL 2) was led by the University of Manchester via its CO-ODE project [15], now ended, which has also been a source for most existing Protégé 4 plug-ins. (Because of the switch to OWL 2 and the OWL API most earlier plug-ins are incompatible with Protégé 4.) Manchester has also been a leading force in the development of OWL 2 and the alternative Manchester syntax.

Though only recently stable because of the formalization of OWL 2, Protégé 4 and its linkage to the new OWL API provides for a very powerful combination. With Protégé, the system has a familiar ontology editing framework and a mechanism for plug-in migration and growth. With the OWL API, there is now a common API for leading reasoners (Pellet, HermiT, FaCT++, RacerPro, etc.), a solid ontology management and annotation framework, and validators for various OWL 2 profiles (RL, EL and QL). The system is widely embraced by the biology community, probably the most active scientific field in ontologies. However, plug-in support lags the diversity of prior versions of Protégé and there does not appear to be the energy and community standing behind it as in prior years.

A Normative Tools Landscape

These leading frameworks and toolkits have opted to be “ontology engineering” environments. Via plug-ins and complicated interfaces (tabs or Eclipse-style panes) the intent has apparently been to provide “all capabilities in one box.” The tools have been IDE-centric.

Unfortunately, one must be a combination of ontologist, developer, programmer and IDE expert in order use the tools effectively. And, as incremental capabilities get added to the systems, these also inherit the same complexity and style of the host environment. It is simply not possible to make complex environments and conventions simple.

Curiously, the existence or use of APIs have also not been adequately leveraged. The usefulness of an API means that subsets of information can be extracted and worked on in very clear and simple ways. This information can then be roundtripped without loss. An API allows a tailored subset abstraction of the underlying data model. In contrast, IDEs, such as Protégé or Eclipse, when they play a similar role, force all interfaces to share their built-in complexity.

With these thoughts in mind, then, we set out to architect a tools suite and work flow that could truly take advantage of a central API. We further wanted to isolate the pieces into distributable Web services in keeping with our standard structWSF Web services framework design.

This approach also allows us to split out simpler, focused tools that domain users and practitioners can use. And, we can do all of this while also enabling the existing professional toolsets and IDEs to also interoperate in the environment.

The resulting tools landscape is shown in the diagram below. This diagram takes the same methodology flow from Figure 1 (blue and yellow boxes) and stretches them out in a more linear fashion. Then, we embed the various tools (brown) and APIs (orange) in relation to that methodology:

Figure 2. The Normative Ontology Tools Landscape (click to expand)

This diagram is worth expanding to full size and studying in some detail. Aspects of this diagram that deserve more discussion are presented in the sections below.

OWL API as Center of Gravity

As noted in the preceding methodology installment, the working ontology is the central object being managed and extended for a given deployment. Because that ontology will evolve and grow over time, it is important the complete ontology specification itself be managed by some form of version control system (green) [16]. This is the one independent tool in the landscape.

Access to and from the working ontology is mediated by the OWL API [13]. The API allows all or portions of the ontology specification to be manipulated separately, with a variety of serializations. Changes made to the ontology can also be tested for validity. Most leading reasoners can interact directly with the API. Protégé 4 also interacts directly with the API, as can various rules engines [17]. Additionally, other existing APIs, notably the Alignment API with its own mapping tools and links to other tools such as S-Match can interact with the OWL API. It is reasonable to expect more APIs to emerge over time that also interoperate [18].

The OWL API is the best current choice because of its native capabilities and because Jena does not yet support OWL 2 [11]. However, because of the basic design with structWSF (see next), it is also possible to swap out with different APIs at a later time should developments warrant.

In short, having the API play the central management role in the system means that any and all tools can be designed to interact effectively with the working ontology(ies) without any loss in information due to roundtripping.

Web Services (structWSF) as Canonical Access Layer

The same rationale that governed our development of structWSF [19] applies here: to abstract basic services and functionality through a platform-independent Web services layer. This Web services layer has canonical (standard) ways to interact with other services and is generally RESTful in design to support distributed deployments. The design conforms to proper separation of view from logic and structure. Moreover, because of the design, changes can be made on either side of the layer in terms of user interface or functionality.

Use of the structWSF layer also means that tools and functionality can be distributed anywhere on the Web. Specialized server-side functions can be supported as well as dedicated specialty hardware. Text indexing or disambiguation services can fit within this design.

The ultimate value of piggybacking on the structWSF framework is that all other extant services also become available. Thus, a wealth of converters, data managers, and semantic components (or display widgets) can be invoked depending on the needs of the specific tool.

Simpler, Task-specific Tools

The objective, of course, of this design is to promote more and simpler tools useful to domain users. Some of these are shown under the Use & Maintain box in the diagram above; others are listed by category in the table below.

The RESTful interface and parameter calls of the structWSF layer further simplify the ontology management and annotation abstractions arising from the OWL API. The number of simple tools available to users under this design is virtually limitless. These tools are also fast to develop and test.

Combining These New Thrusts and Moving Forward

This landscape is not yet a full reality. It is a vision of adaptive and simpler tools, working with a common API, and accessible via platform-independent Web services. It also preserves many of the existing tools and IDEs familiar to present ontology engineers.

However, pieces of this landscape do presently exist and more are on the way. The next section briefly overviews some of the major application areas where these tools might contribute.

Individual Tools within the Landscape

If one inspects the earlier listing of 185 ontology tools it is clear that there is a diversity of tools both in terms of scope and function across the entire ontology development stack. It is also clear that nearly all of those 185 tools listed do not communicate with one another. That is a tremendous waste.

Via shared APIs and some degree of consistent design it should be possible to migrate these capabilities into a more-or-less interoperating whole. We have thus tried to categorize some important tool types and exemplar tools from that listing to show the potential that exists. (Please note that the Example Tools are links to the tools and categories from the earlier 185 tools listing.)

This correlation of types and example tools is not meant to be exhaustive nor a recommendation of specific tools. But, this tabulation is illustrative of the potential that exists to both simplify and extend tool support across the entire ontology development workflow:

The beauty of this approach is that most of the tools listed are open source and potentially amenable to the minor modifications necessary to conform with this proposed landscape.

Key Gaps in the Landscape

Contrasting the normative tools landscape above with the existing listing of ontology tools points out some key gaps or areas deserving more development attention. Some of these are:

• Vocabulary managers — easy inspection and editing environments for concepts and predicates are lacking. Though standard editors allow direct ontology language edits (OWL or RDFS), these are not presently navigable or editable by non-ontologists. Intuitive browsing structures with more “infobox”-like editing environments could be helpful here
• Graph API — it would be wonderful to have a graph API (including analysis options) that could communicate with the OWL API. Failing that, it would be helpful to have a graph API that communicated well with RDF and ontology structures; extant options are few
• Large-graph visualizer — while we have earlier reviewed large-scale graph visualization software, the alternatives are neither easy to set up nor use. Being able to readily select layout options with quick zooms and scaling options are important
• Graphical editor — some browsers or editors (e.g, FlexViz) provide nice graph-based displays of ontologies and their properties and annotations. However, there appear to be few environments where the ontology graph can be directly edited or visually used for design or expansion.

Finally, it does appear that the effort and focus behind Protégé seems to be slowing somewhat. The future has clearly shifted to OWL 2 with Protégé 4. Yet, besides the admirable CO-ODE project (now ended), tools and plug-in support seems to have slowed. Many of the admirable plug-ins for Protégé 3x do not appear to be under active development as upgrades to Protégé 4. While Protégé’s future (and similar IDEs) seems assured, its prominence possibly will (and should) be replaced by a simpler kit of tools useful to users and practitioners.

Funding and Pending Project Priorities

For the past few months we at Structured Dynamics have seen ontology design and management as the pending technical priorities within the semantic technology space. Now that the market no longer looks at “ontology” as a four-letter word, it is imperative to simplify the development and use of ontologies. The first generation of tools leading up to this point have been helpful to understand the semantic space; changes are now necessary to expand it.

In our first generation we have begun to understand the types and nature of needed tools. But our focus on IDEs and comprehensive toolsets belies a developer’s or technologist’s perspective. We need to now shift focus and look at tool needs from the standpoint of users and actual use of ontologies. Many players and many toolmakers and innovators will need to contribute to build this market for semantic technologies and approaches.

Fortunately, replacing an IDE focus with one based around APIs and Web services should be a fairly smooth and natural transition. If we truly desire to be market makers, we need to stand back and place ourselves into the shoes of the domain practitioners, the subject matter experts. We need to shield actual users from all of the silly technical details and complexity. And, then, let’s focus — task-by-task — on discrete items of management and use of ontologies. Growth of the semantic technology space depends on expanding our practitioner base.

For its part, Structured Dynamics is presently seeking new projects and sponsors with a commitment to these aims. Like our prior development of structWSF and semantic components, we will be looking to make simpler ontology tools a priority in the coming months. Please let me know if you want to partner with us toward this commitment.

Earlier Listing is Expanded by More than 30%

At the beginning of this year Structured Dynamics assembled a listing of ontology building tools at the request of a client. That listing was presented as The Sweet Compendium of Ontology Building Tools. Now, again because of some client and internal work, we have researched the space again and updated the listing [1].

All new tools are marked with <New> (new only means newly discovered; some had yet to be discovered in the prior listing). There are now a total of 185 tools in the listing, 31 of which are recently new, and 45 added at various times since the first release. <Newest> reflects updates — most from the developers themselves — since the original publication of this post.

Comprehensive Ontology Tools

• Altova SemanticWorks is a visual RDF and OWL editor that auto-generates RDF/XML or nTriples based on visual ontology design. No open source version available
• Amine is a rather comprehensive, open source platform for the development of intelligent and multi-agent systems written in Java. As one of its components, it has an ontology GUI with text- and tree-based editing modes, with some graph visualization
• The Apelon DTS (Distributed Terminology System) is an integrated set of open source components that provides comprehensive terminology services in distributed application environments. DTS supports national and international data standards, which are a necessary foundation for comparable and interoperable health information, as well as local vocabularies. Typical applications for DTS include clinical data entry, administrative review, problem-list and code-set management, guideline creation, decision support and information retrieval.. Though not strictly an ontology management system, Apelon DTS has plug-ins that provide visualization of concept graphs and related functionality that make it close to a complete solution
• DOME is a programmable XML editor which is being used in a knowledge extraction role to transform Web pages into RDF, and available as Eclipse plug-ins. DOME stands for DERI Ontology Management Environment
• FlexViz is a Flex-based, Protégé-like client-side ontology creation, management and viewing tool; very impressive. The code is distributed from Sourceforge; there is a nice online demo available; there is a nice explanatory paper on the system, and the developer, Chris Callendar, has a useful blog with Flex development tips
• <Newest> ITM supports the management of complex knowledge structures (metadata repositories, terminologies, thesauri, taxonomies, ontologies, and knowledge bases) throughout their lifecycle, from authoring to delivery. ITM can also manage alignments between multiple knowledge structures, such as thesauri or ontologies, via the integration of INRIA’s Alignment API. Commercial; from Mondeca
• Knoodl facilitates community-oriented development of OWL based ontologies and RDF knowledge bases. It also serves as a semantic technology platform, offering a Java service-based interface or a SPARQL-based interface so that communities can build their own semantic applications using their ontologies and knowledgebases. It is hosted in the Amazon EC2 cloud and is available for free; private versions may also be obtained. See especially the screencast for a quick introduction
• The NeOn toolkit is a state-of-the-art, open source multi-platform ontology engineering environment, which provides comprehensive support for the ontology engineering life-cycle. The v2.3.0 toolkit is based on the Eclipse platform, a leading development environment, and provides an extensive set of plug-ins covering a variety of ontology engineering activities. You can add these plug-ins or get a current listing from the built-in updating mechanism
• ontopia is a relative complete suite of tools for building, maintaining, and deploying Topic Maps-based applications; open source, and written in Java. Could not find online demos, but there are screenshots and there is visualization of topic relationships
• Protégé is a free, open source visual ontology editor and knowledge-base framework. The Protégé platform supports two main ways of modeling ontologies via the Protégé-Frames and Protégé-OWL editors. Protégé ontologies can be exported into a variety of formats including RDF(S), OWL, and XML Schema. There are a large number of third-party plugins that extends the platform’s functionality
  • Protégé Plugin Library – frequently consult this page to review new additions to the Protégé editor; presently there are dozens of specific plugins, most related to the semantic Web and most open source
  • Collaborative Protégé is a plug-in extension of the existing Protégé system that supports collaborative ontology editing as well as annotation of both ontology components and ontology changes. In addition to the common ontology editing operations, it enables annotation of both ontology components and ontology changes. It supports the searching and filtering of user annotations, also known as notes, based on different criteria. There is also an online demo
  • <New>Web Protégé is an online version of Protégé attempting to capture all of the native functionality; still under development
• <New>Sigma is open source knowledge engineering environment that includes ontology mapping, theorem proving, language generation in multiple languages, browsing, OWL read/write, and analysis. It includes the Suggested Upper Merged Ontology (SUMO), a comprehensive formal ontology. It’s under active development and use
• TopBraid Composer is an enterprise-class modeling environment for developing Semantic Web ontologies and building semantic applications. Fully compliant with W3C standards, Composer offers comprehensive support for developing, managing and testing configurations of knowledge models and their instance knowledge bases. It is based on the Eclipse IDE. There is a free version (after registration) for small ontologies
• <New>TwoUse Toolkit is an implementation of current OMG and W3C standards for developing ontology-based software models and model-based OWL2 ontologies, largely based around UML. There are a variety of tools, including graphics editors, with more to come
• <New>Wandora is a topic maps engine written in Java with support for both in-memory topic maps and persisting topic maps in MySQL and SQL Server. It also contains an editor and a publishing system, and has support for automatic classification. It can read OBO, RDF(S), and many other formats, and can export topic maps to various graph formats. There is also a web-based topic maps browser, and graphical visualization.

Not Apparently in Active Use

• Adaptiva is a user-centred ontology building environment, based on using multiple strategies to construct an ontology, minimising user input by using adaptive information extraction
• Exteca is an ontology-based technology written in Java for high-quality knowledge management and document categorisation, including entity extraction. Though code is still available, no updates have been provided since 2006. It can be used in conjunction with search engines
• IODT is IBM’s toolkit for ontology-driven development. The toolkit includes EMF Ontolgy Definition Metamodel (EODM), EODM workbench, and an OWL Ontology Repository (named Minerva)
• KAON is an open-source ontology management infrastructure targeted for business applications. It includes a comprehensive tool suite allowing easy ontology creation and management and provides a framework for building ontology-based applications. An important focus of KAON is scalable and efficient reasoning with ontologies
• Ontolingua provides a distributed collaborative environment to browse, create, edit, modify, and use ontologies. The server supports over 150 active users, some of whom have provided us with descriptions of their projects. Provided as an online service; software availability not known.

Vocabulary Prompting Tools

• AlchemyAPI from Orchestr8 provides an API based application that uses statistical and natural language processing methods. Applicable to webpages, text files and any input text in several languages
• BooWa is a set expander for any language (formerly known as SEALS); developed by RC Wang of Carnegie Mellon
• Google Keywords allows you to enter a few descriptive words or phrases or a site URL to generate keyword ideas
• Google Sets for automatically creating sets of items from a few examples
• Open Calais is free limited API web service to automatically attach semantic metadata to content, based on either entities (people, places, organizations, etc.), facts (person ‘x’ works for company ‘y’), or events (person ‘z’ was appointed chairman of company ‘y’ on date ‘x’). The metadata results are stored centrally and returned to you as industry-standard RDF constructs accompanied by a Globally Unique Identifier (GUID)
• Query-by-document from BlogScope has a nice phrase extraction service, with a choice of ranking methods. Can also be used in a Firefox plug-in (not texted with 3.5+)
• SemanticHacker (from Textwise) is an API that does a number of different things, including categorization, search, etc. By using ‘concept tags’, the API can be leveraged to generate metadata or tags for content
• TagFinder is a Web service that automatically extracts tags from a piece of text. The tags are chosen based on both statistical and linguistic analysis of the original text
• Tagthe.net has a demo and an API for automatic tagging of web documents and texts. Tags can be single words only. The tool also recognizes named entities such as people names and locations
• TermExtractor extracts terminology consensually referred in a specific application domain. The software takes as input a corpus of domain documents, parses the documents, and extracts a list of “syntactically plausible” terms (e.g. compounds, adjective-nouns, etc.)
• TermFinder uses Poisson statistics, the Maximum Likelihood Estimation and Inverse Document Frequency between the frequency of words in a given document and a generic corpus of 100 million words per language; available for English, French and Italian
• TerMine is an online and batch term extractor that emphasizes part of speech (POS) and n-gram (phrase extraction). TerMine is the terminological management system with the C-Value term extraction and AcroMine acronym recognition integrated
• Topia term extractor is a part-of-speech and frequency based term extraction tool implemented in python. Here is a term extraction demo based on this tool
• Topicalizer is a service which automatically analyses a document specified by a URL or a plain text regarding its word, phrase and text structure. It provides a variety of useful information on a given text including the following: Word, sentence and paragraph count, collocations, syllable structure, lexical density, keywords, readability and a short abstract on what the given text is about

• TrMExtractor does glossary extraction on pure text files for either English or Hungarian

• Wikify! is a system to automatically “wikify” a text by adding Wikipedia-like tags throughout the document. The system extracts keywords and then disambiguates and matches them to their corresponding Wikipedia definition
• Yahoo! Placemaker is a freely available geoparsing Web service. It helps developers make their applications location-aware by identifying places in unstructured and atomic content – feeds, web pages, news, status updates – and returning geographic metadata for geographic indexing and markup
• Yahoo! Term Extraction Service is an API to Yahoo’s term extraction service, as well as many other APIs and services in a variety of languages and for a variety of tasks; good general resource. The service has been reported to be shut down numerous times, but apparently is kept alive due to popular demand.

Initial Ontology Development

• COE COE (CmapTools Ontology Editor) is a specialized version of the CmapTools from IMHC. COE — and its CmapTools parent — is based on the idea of concept maps. A concept map is a graph diagram that shows the relationships among concepts. Concepts are connected with labeled arrows, with the relations manifesting in a downward-branching hierarchical structure. COE is an integrated suite of software tools for constructing, sharing and viewing OWL encoded ontologies based on these constructs
• Conzilla2 is a second generation concept browser and knowledge management tool with many purposes. It can be used as a visual designer and manager of RDF classes and ontologies, since its native storage is in RDF. It also has an online collaboration server [apparently last updated in 2008]
• http://diagramic.com/ has an online Flex network graph demo, which also has a neat facility for quick entry and visualization of relationships; mostly small scale; pretty cool. Does not appear to be code available anywhere
• <New>DL-Learner is a tool for learning OWL class expressions from examples and background knowledge. It extends Inductive Logic Programming (ILP) to Description Logics and the Semantic Web. DL-Learner now has a flexible component based design, which allows to extend it easily with new learning algorithms, learning problems, reasoners, and supported background knowledge sources. A new type of supported knowledge sources are SPARQL endpoints, where DL-Learner can extract knowledge fragments, which enables learning classes even on large knowledge sources like DBpedia, and includes an OWL API reasoner interface and Web service interface.
• DogmaModeler is a free and open source, ontology modeling tool based on ORM. The philosophy of DogmaModeler is to enable non-IT experts to model ontologies with a little or no involvement of an ontology engineer; project is quite old, but the software is still available and it may provide some insight into naive ontology development
• Erca is a framework that eases the use of Formal and Relational Concept Analysis, a neat clustering technique. Though not strictly an ontology tool, Erca could be implemented in a work flow that allows easy import of formal contexts from CSV files, then algorithms that computes the concept lattice of the formal contexts that can be exported as dot graphs (or in JPG, PNG, EPS and SVG formats). Erca is provided as an Eclipse plug-in
• GraphMind is a mindmap editor for Drupal. It has the basic mindmap features and some Drupal specific enhancements. There is a quick screencast about how GraphMind looks like and what is does. The Flex source is also available from Github
• <New>H-Maps is a commercial suite of tools for building topic maps applications, consisting of a topic maps engine and server, a mapping framework for converting from legacy data, and a navigator for visualizing data. It is typically used in bioinformatics (drug discovery and research, toxicological studies, etc), engineering (support and expert systems), and for integration of hetereogeneous data. It supports the XTM 1.0 and TMAPI 1.0 specifications
• irON using spreadsheets, via its notation and specification. Spreadsheets can be used for initial authoring, esp if the irON guidelines are followed. See further this case study of Sweet Tools in a spreadsheet using irON (commON)
• <New>JXML2OWL API is a library for mapping XML schemas to OWL Ontologies on the JAVA platform. It creates an XSLT which transforms instances of the XML schema into instances of the OWL ontology. JXML2OWL Mapper is GUI application using the JXML2OWL API
• MindRaider is Semantic Web outliner. It aims to connect the tradition of outline editors with emerging technologies. MindRaider mission is to organize not only the content of your hard drive but also your cognitive base and social relationships in a way that enables quick navigation, concise representation and inferencing
• <New>Neologism is a simple web-based RDF Schema vocabulary editor and publishing system. Use it to create RDF classes and properties, which are needed to publish data on the Semantic Web. Its main goal is to dramatically reduce the time required to create, publish and modify vocabularies for the Semantic Web. It is written in PHP and built on the Drupal platform. Neologism is currently in alpha
• <New>OCS – Ontology Creation System is software to develop ontologies in cooperative way with a graphical interface
• RDF123 is an application and web service for converting data in simple spreadsheets to an RDF graph. Users control how the spreadsheet’s data is converted to RDF by constructing a graphical RDF123 template that specifies how each row in the spreadsheet is converted as well as metadata for the spreadsheet and its RDF translation
• <New>ROC (Rapid Ontology Construction) is a tool that allows domain experts to quickly build a basic vocabulary for their domain, re-using existing terminology whenever possible. How this works is that the ROC tool asks the domain expert for a set of keywords that are ‘core’ terms of the domain, and then queries remote sources for concepts matching those terms. These are then presented to the user, who can select terms from the list, find relations to other terms, and expand the set of terms and relations, iteratively. The resulting vocabulary (or ‘proto-ontology’, basically a SKOS-like thesaurus) can be used as is, or can be used as input for a knowledge engineer to base a more comprehensive domain ontology on. Interface “triples-oriented,” not graphical.
• Topincs is a Topic Map authoring software that allows groups to share their knowledge over the web. It makes use of a variety of modern technologies. The most important are Topic Maps, REST and Ajax. It consists of three components: the Wiki, the Editor, and the Server. The servier requires AMP; the Editor and Wiki are based on browser plug-ins.

Ontology Editing

• First, see all of the Comprehensive Tools and Ontology Development listings above
• Anzo for Excel includes an (RDFS and OWL-based) ontology editor that can be used directly within Excel. In addition to that, Anzo for Excel includes the capability to automatically generate an ontology from existing spreadsheet data, which is very useful for quick bootstrapping of an ontology
• <New>ATop is a topic map browser and editor written in Java and supports the XTM 1.0 specification; project has not been updated since 2008
• Hozo is an ontology visualization and development tool that brings version control constructs to group ontology development; limited to a prototype, with no online demo
• Lexaurus Editor is for off-line creation and editing of vocabularies, taxonomies and thesauri. It supports import and export in Zthes and SKOS XML formats, and allows hierarchical / poly-hierarchical structures to be loaded for editing, or even multiple vocabularies to be loaded simultaneously, so that terms from one taxonomy can be re-used in another, using drag and drop. Not available in open source
• Model Futures OWL Editor combines simple OWL tools, featuring UML (XMI), ErWin, thesaurus and imports. The editor is tree-based and has a “navigator” tool for traversing property and class-instance relationships. It can import XMI (the interchange format for UML) and Thesaurus Descriptor (BT-NT XML), and EXPRESS XML files. It can export to MS Word.
• <New>OBO-Edit is an open source ontology editor written in Java. OBO-Edit is optimized for the OBO biological ontology file format. It features an easy to use editing interface, a simple but fast reasoner, and powerful search capabilities
• <New>Onotoa is an Eclipse-based ontology editor for topic maps. It has a graphical UML-like interface, an export function for the current TMCL-draft and a XTM export
• OntoTrack is a browsing and editing ontology authoring tool for OWL Lite. It combines a sophisticated graphical layout with mouse enabled editing features optimized for efficient navigation and manipulation of large ontologies
• OWLViz is an attractive visual editor for OWL and is available as a Protégé plug-in
• PoolParty is a triple store-based thesaurus management environment which uses SKOS and text extraction for tag recommendations. See further this manual, which describes more fully the system’s functionality. Also, there is a PoolParty Web service that enables a Zthes thesaurus in XML format to be uploaded and converted to SKOS (via skos:Concepts)
• SKOSEd is a plugin for Protege 4 that allows you to create and edit thesauri (or similar artefacts) represented in the Simple Knowledge Organisation System (SKOS).
• TemaTres is a Web application to manage controlled vocabularies, taxonomies and thesaurus. The vocabularies may be exported in Zthes, Skos, TopicMap, etc.
• ThManager is a tool for creating and visualizing SKOS RDF vocabularies. ThManager facilitates the management of thesauri and other types of controlled vocabularies, such as taxonomies or classification schemes
• Vitro is a general-purpose web-based ontology and instance editor with customizable public browsing. Vitro is a Java web application that runs in a Tomcat servlet container. With Vitro, you can: 1) create or load ontologies in OWL format; 2) edit instances and relationships; 3) build a public web site to display your data; and 4) search your data with Lucene. Still in somewhat early phases, with no online demos and with minimal interfaces.
• <New>Vocab Editor is an RDF/OWL/SKOS vocabulary-diagram editor. It has both client- (Javascript) and server-side (Python) implmentations. It is open source with a demo. There is a blog (Spanish) and online sample vocabulary app editor.

Not Apparently in Active Use

• Omnigator The Omnigator is a form-based manipulaton tool centered on Topic Maps, though it enables the loading and navigation of any conforming topic map in XTM, HyTM, LTM or RDF formats. There is a free evaluation version.
• OntoGen is a semi-automatic and data-driven ontology editor focusing on editing of topic ontologies (a set of topics connected with different types of relations). The system combines text-mining techniques with an efficient user interface. It requires .Net.
• OntoLight is a set of software modules for: transforming raw ontology data for several ontologies from their specific formats into a unifying light-weight ontology format, grounding the ontology and storing it into grounded ontology format, populating grounded ontologies with new instance data, and creating mappings between grounded ontologies; includes Cyc. Download no longer available. See http://analytics.ijs.si/~blazf/papers/Context_SiKDD07.pdf and http://www.neon-project.org/web-content/index.php?option=com_weblinks&task=view&catid=17&id=52 or http://www.neon-project.org/web-content/index.php?option=com_weblinks&catid=21&Itemid=73
• OWL-S-editor is an editor for the development of services in OWL-S, with graphical, WSDL and import/export support
• ReTAX+ is an aide to help a taxonomist create a consistent taxonomy and in particular provides suggestions as to where a new entity could be placed in the taxonomy whilst retaining the integrity of the revised taxonomy (c.f., problems in ontology modelling)
• SWOOP is a lightweight ontology editor. (Swoop is no longer under active development at mindswap. Continuing development can be found on SWOOP’s Google Code homepage at http://code.google.com/p/swoop/)
• WebOnto supports the browsing, creation and editing of ontologies through coarse grained and fine grained visualizations and direct manipulation.

Ontology Mapping

• <New>The Alignment API is an API and implementation for expressing and sharing ontology alignments. The correspondences between entities (e.g., classes, objects, properties) in ontologies is called an alignment. The API provides a format for expressing alignments in a uniform way. The goal of this format is to be able to share on the web the available alignments. The format is expressed in RDF, so it is freely extensible. The Alignment API itself is a Java description of tools for accessing the common format. It defines four main interfaces (Alignment, Cell, Relation and Evaluator).
• COMA++ is a schema and ontology matching tool with a comprehensive infrastructure. Its graphical interface supports a variety of interaction
• ConcepTool is a system to model, analyse, verify, validate, share, combine, and reuse domain knowledge bases and ontologies, reasoning about their implication
• <New>MapOnto is a research project aiming at discovering semantic mappings between different data models, e.g, database schemas, conceptual schemas, and ontologies. So far, it has developed tools for discovering semantic mappings between database schemas and ontologies as well as between different database schemas. The Protege plug-in is still available, but appears to be for older versions
• MatchIT automates and facilitates schema matching and semantic mapping between different Web vocabularies. MatchIT runs as a stand-alone or plug-in Eclipse application and can be integrated with popular third party applications. MatchIT’s uses Adaptive Lexicon™ as an ontology-driven dictionary and thesaurus of English language terminology to quantify and ank the semantic similarity of concepts. It apparently is not available in open source
• myOntology is used to produce the theoretical foundations, and deployable technology for the Wiki-based, collaborative and community-driven development and maintenance of ontologies instance data and mappings
• OLA/OLA2 (OWL-Lite Alignment) matches ontologies written in OWL. It relies on a similarity combining all the knowledge used in entity descriptions. It also deal with one-to-many relationships and circularity in entity descriptions through a fixpoint algorithm
• Potluck is a Web-based user interface that lets casual users—those without programming skills and data modeling expertise—mash up data themselves. Potluck is novel in its use of drag and drop for merging fields, its integration and extension of the faceted browsing paradigm for focusing on subsets of data to align, and its application of simultaneous editing for cleaning up data syntactically. Potluck also lets the user construct rich visualizations of data in-place as the user aligns and cleans up the data.
• PRIOR+ is a generic and automatic ontology mapping tool, based on propagation theory, information retrieval technique and artificial intelligence model. The approach utilizes both linguistic and structural information of ontologies, and measures the profile similarity and structure similarity of different elements of ontologies in a vector space model (VSM).
• <New>S-Match takes any two tree like structures (such as database schemas, classifications, lightweight ontologies) and returns a set of correspondences between those tree nodes which semantically correspond to one another.
• Vine is a tool that allows users to perform fast mappings of terms across ontologies. It performs smart searches, can search using regular expressions, requires a minimum number of clicks to perform mappings, can be plugged into arbitrary mapping framework, is non-intrusive with mappings stored in an external file, has export to text files, and adds metadata to any mapping. See also http://sourceforge.net/projects/vine/.

Not Apparently in Active Use

• ASMOV (Automated Semantic Mapping of Ontologies with Validation) is an automatic ontology matching tool which has been designed in order to facilitate the integration of heterogeneous systems, using their data source ontologies
• Chimaera is a software system that supports users in creating and maintaining distributed ontologies on the web. Two major functions it supports are merging multiple ontologies together and diagnosing individual or multiple ontologies
• CMS (CROSI Mapping System) is a structure matching system that capitalizes on the rich semantics of the OWL constructs found in source ontologies and on its modular architecture that allows the system to consult external linguistic resources
• ConRef is a service discovery system which uses ontology mapping techniques to support different user vocabularies
• DRAGO reasons across multiple distributed ontologies interrelated by pairwise semantic mappings, with a vision of peer-to-peer mapping of many distributed ontologies on the Web. It is implemented as an extension to an open source Pellet OWL Reasoner
• Falcon-AO (Finding, aligning and learning ontologies) is an automatic ontology matching tool that includes the three elementary matchers of String, V-Doc and GMO. In addition, it integrates a partitioner PBM to cope with large-scale ontologies
• FOAM is the Framework for ontology alignment and mapping. It is based on heuristics (similarity) of the individual entities (concepts, relations, and instances)
• hMAFRA (Harmonize Mapping Framework) is a set of tools supporting semantic mapping definition and data reconciliation between ontologies. The targeted formats are XSD, RDFS and KAON
• IF-Map is an Information Flow based ontology mapping method. It is based on the theoretical grounds of logic of distributed systems and provides an automated streamlined process for generating mappings between ontologies of the same domain
• LILY is a system matching heterogeneous ontologies. LILY extracts a semantic subgraph for each entity, then it uses both linguistic and structural information in semantic subgraphs to generate initial alignments. The system is presently in a demo version only
• MAFRA Toolkit – the Ontology MApping FRAmework Toolkit allows users to create semantic relations between two (source and target) ontologies, and apply such relations in translating source ontology instances into target ontology instances
• OntoEngine is a step toward allowing agents to communicate even though they use different formal languages (i.e., different ontologies). It translates data from a “source” ontology to a “target”
• OWLS-MX is a hybrid semantic Web service matchmaker. OWLS-MX 1.0 utilizes both description logic reasoning, and token based IR similarity measures. It applies different filters to retrieve OWL-S services that are most relevant to a given query
• RiMOM (Risk Minimization based Ontology Mapping) integrates different alignment strategies: edit-distance based strategy, vector-similarity based strategy, path-similarity based strategy, background-knowledge based strategy, and three similarity-propagation based strategies
• semMF is a flexible framework for calculating semantic similarity between objects that are represented as arbitrary RDF graphs. The framework allows taxonomic and non-taxonomic concept matching techniques to be applied to selected object properties
• Snoggle is a graphical, SWRL-based ontology mapper. Snoggle attempts to solve the ontology mapping problem by providing a graphical user interface (similar to which of the Microsoft Visio) to guide the process of ontology vocabulary alignment. In Snoggle, user-defined mappings can be serialized into rules, which is expressed using SWRL
• Terminator is a tool for creating term to ontology resource mappings (documentation in Finnish).

Ontology Visualization/Analysis

Though all are not relevant, see my post from a couple of years back on large-scale RDF graph software.

• Social network graphing tools (many covered elsewhere)
• Cytoscape is a bioinformatics software platform for visualizing molecular interaction networks and integrating these interactions with gene expression profiles and other state data; I have also written specifically about Cytoscape’s use in UMBEL
  • RDFScape is a project that brings Semantic Web “features” to the popular Systems Biology software Cytoscape
  • NetworkAnalyzer performs analysis of biological networks and calculates network topology parameters including the diameter of a network, the average number of neighbors, and the number of connected pairs of nodes. It also computes the distributions of more complex network parameters such as node degrees, average clustering coefficients, topological coefficients, and shortest path lengths. It displays the results in diagrams, which can be saved as images or text files; used by SD
• Graphl is a tool for collaborative editing and visualisation of graphs, representing relationships between resources or concepts of the real world. Graphl may be thought of as a visual wiki, a place where everybody can contribute to a shared repository of knowledge
• <New>Graphviz is open source graph visualization software. It has several main graph layout programs. It also has web and interactive graphical interfaces, and auxiliary tools, libraries, and language bindings.
• <New>GrOWL is an ontology visualizer and editor. The layout of the GrOWL graph can be defined automatically or loaded from a separate style sheet. GrOWL implements configurable filters that can transform the display by simplifying it, hiding concepts and relationships that have no descriptions associated, or perform more complex translations. Concepts can be stored in ontologies with extensive annotations to provide documentation. GrOWL shows these annotation as tooltips, and supports complex HTML and links within them. The GrOWL browser can be used inside a web browser or as a stand-alone application. When used inside a browser, it supports Javascript interaction so that it can be used as a concept chooser with implementation-defined operations.
• igraph is a free software package for creating and manipulating undirected and directed graphs
• Network Workbench is a very complex, comprehensive; Swiss Army Knife
• NetworkX – Python; very clean
• <New>OntoGraf, a Protege 4 plug-in, gives support for interactively navigating the relationships of your OWL ontologies. Various layouts are supported for automatically organizing the structure of your ontology. Different relationships are supported: subclass, individual, domain/range object properties, and equivalence. Relationships and node types can be filtered.
• <New>OWL2Prefuse is a Java package which creats Prefuse graphs and trees from OWL files (and Jena OntModels). It takes care of converting the OWL data structure to the Prefuse datastructure. This makes it is easy for developers, to use the Prefuse graphs and trees into their Semantic Web applications.
• <New>RDF Gravity is a tool for visualising RDF/OWL Graphs/ ontologies. RDF Gravity is implemented by using the JUNG Graph API and Jena semantic web toolkit. Its main features are:
  • Graph Visualization
  • Global and Local Filters (enabling specific views on a graph)
  • Full text Search
  • Generating views from RDQL Queries
  • Visualising multiple RDF files
• <Newest> SKOS Reader is a SKOS browser and an HTML renderer of SKOS thesauri and terminologies that can display a SKOS file hierarchically, alphabetically, or permuted. Commercial; from Mondeca
• Stanford Network Analysis Package (SNAP) is a general purpose network analysis and graph mining library. It is written in C++ and easily scales to massive networks with hundreds of millions of nodes
• Social Networks Visualizer (SocNetV) is a flexible and user-friendly tool for the analysis and visualization of Social Networks. It lets you construct networks (mathematical graphs) with a few clicks on a virtual canvas or load networks of various formats (GraphViz, GraphML, Adjacency, Pajek, UCINET, etc) and modify them to suit your needs. SocNetV also offers a built-in web crawler, allowing you to automatically create networks from all links found in a given initial URL
• Tulip may be incredibly strong
  • quite active (but not much online stuff): http://sourceforge.net/projects/auber/files/
• Springgraph component for Flex
• VizierFX is a Flex library for drawing network graphs. The graphs are laid out using GraphViz on the server side, then passed to VizierFX to perform the rendering. The library also provides the ability to run ActionScript code in response to events on the graph, such as mousing over a node or clicking on it.
• <New>VUE (Visual Understanding Environment) is an open source project focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information.
• <New>yEd is a diagram editor that can be used to quickly and effectively generate high-quality drawings of diagrams. It can support OWL imports.
• <New>ZGRViewer is a graph visualizer implemented in Java and based upon the Zoomable Visual Transformation Machine. It is specifically aimed at displaying graphs expressed using the DOT language from AT&T GraphViz and processed by programs dot, neato or others such as twopi. ZGRViewer is designed to handle large graphs, and offers a zoomable user interface (ZUI), which enables smooth zooming and easy navigation in the visualized structure.

Miscellaneous Ontology Tools

• Apolda (Automated Processing of Ontologies with Lexical Denotations for Annotation) is a plugin (processing resource) for GATE (http://gate.ac.uk/). The Apolda processing resource (PR) annotates a document like a gazetteer, but takes the terms from an (OWL) ontology rather than from a list
• <Newest>CA Manager supports customized workflows for semantic annotation of content. Commercial; from Mondeca
• <New>Gloze is a XML to RDF, RDF to XML, and XSD to OWL mapping tool based on Jena; see also http://jena.hpl.hp.com/juc2006/proceedings/battle/paper.pdf . See also http://jena.sourceforge.net/contrib/contributions.html
• <New>Hoolet is an implementation of an OWL-DL reasoner that uses a first order prover. The ontology is translated to collection of axioms (in an obvious way based on the OWL semantics) and this collection of axioms is then given to a first order prover for consistency checking.
• LexiLink is a tool for building, curating and managing multiple lexicons and ontologies in one enterprise-wide Web-based application. The core of the technology is based on RDF and OWL
• mopy is the Music Ontology Python library, designed to provide easy to use python bindings for ontology terms for the creation and manipulation of music ontology data. mopy can handle information from several ontologies, including the Music Ontology, full FOAF vocab, and the timeline and chord ontologies
• OBDA (Ontology Based Data Access) is a plugin for Protégé aimed to be a full-fledged OBDA ontology and component editor. It provides data source and mapping editors, as well as querying facilities that, in sum, allow you to design and test every aspect of an OBDA system. It supports relational data sources (RDBMS) and GLAV-like mappings. In its current beta form, it requires Protege 3.3.1, a reasoner implementing the OBDA extensions to DIG 1.1 (e.g., the DIG server for QuOnto) and Jena 2.5.5
• <New>oBrowse is a web based ontology browser developed in java. oBrowse parses OWL files of an ontology and displays ontology in a tree view. Protege-API, JSF are used in development
• OntoComP is a Protégé 4 plugin for completing OWL ontologies. It enables the user to check whether an OWL ontology contains “all relevant information” about the application domain, and extend the ontology appropriately if this is not the case
• Ontology Browser is a browser created as part of the CO-ODE (http://www.co-ode.org/) project; rather simple interface and use
• Ontology Metrics is a web-based tool that displays statistics about a given ontology, including the expressivity of the language it is written in
• <New>OntoLT aims at a more direct connection between ontology engineering and linguistic analysis. OntoLT is a Protégé plug-in, with which concepts (Protégé classes) and relations (Protégé slots) can be extracted automatically from linguistically annotated text collections. It provides mapping rules, defined by use of a precondition language that allow for a mapping between linguistic entities in text and class/slot candidates in Protégé. Only available for older Protégé versions
• OntoSpec is a SWI-Prolog module, aiming at automatically generating XHTML specification from RDF-Schema or OWL ontologies
• OWL API is a Java interface and implementation for the W3C Web Ontology Language (OWL), used to represent Semantic Web ontologies. The API is focused towards OWL Lite and OWL DL and offers an interface to inference engines and validation functionality
• OWL Module Extractor is a Web service that extracts a module for a given set of terms from an ontology. It is based on an implementation of locality-based modules that is part of the OWL API.
• OWL Syntax Converter is an online tool for converting ontologies between different formats, including several OWL syntaxes, RDF/XML, KRSS
• OWL Verbalizer is an on-line tool that verbalizes OWL ontologies in (controlled) English
• OwlSight is an OWL ontology browser that runs in any modern web browser; it’s developed with Google Web Toolkit and uses Gwt-Ext, as well as OWL-API. OwlSight is the client component and uses Pellet as its OWL reasoner
• Pellint is an open source lint tool for Pellet which flags and (optionally) repairs modeling constructs that are known to cause performance problems. Pellint recognizes several patterns at both the axiom and ontology level.
• PROMPT is a tab plug-in for Protégé is for managing multiple ontologies by comparing versions of the same ontology, moving frames between included and including project, merging two ontologies into one, or extracting a part of an ontology
• <New>ReDeFer is a compendium of RDF-aware utilities organised in a set of packages: RDF2HTML+RDFa: render a piece of RDF/XML as HTML+RDFa; XSD2OWL: transform an XML Schema into an OWL Ontology; CS2OWL: transform a MPEG-7 Classification Scheme into an OWL Ontology; XML2RDF: transform a piece of XML into RDF; and RDF2SVG: render a piece of RDF/XML as a SVG showing the corresponding graph
• SegmentationApp is a Java application that segments a given ontology according to the approach described in “Web Ontology Segmentation: Analysis, Classification and Use” (http://www.co-ode.org/resources/papers/seidenberg-www2006.pdf)
• SETH is a software effort to deeply integrate Python with Web Ontology Language (OWL-DL dialect). The idea is to import ontologies directly into the programming context so that its classes are usable alongside standard Python classes
• SKOS2GenTax is an online tool that converts hierarchical classifications available in the W3C SKOS (Simple Knowledge Organization Systems) format into RDF-S or OWL ontologies
• SpecGen (v5) is an ontology specification generator tool. It’s written in Python using Redland RDF library and licensed under the MIT license
• Text2Onto is a framework for ontology learning from textual resources that extends and re-engineers an earlier framework developed by the same group (TextToOnto). Text2Onto offers three main features: it represents the learned knowledge at a metalevel by instantiating the modelling primitives of a Probabilistic Ontology Model (POM), thus remaining independent from a specific target language while allowing the translation of the instantiated primitives
• Thea is a Prolog library for generating and manipulating OWL (Web Ontology Language) content. Thea OWL parser uses SWI-Prolog’s Semantic Web library for parsing RDF/XML serialisations of OWL documents into RDF triples and then it builds a representation of the OWL ontology
• TONES Ontology Repository is primarily designed to be a central location for ontologies that might be of use to tools developers for testing purposes; it is part of the TONES project
• Visual Ontology Manager (VOM) is a family of tools enables UML-based visual construction of component-based ontologies for use in collaborative applications and interoperability solutions.
• Web Ontology Manager is a lightweight, Web-based tool using J2EE for managing ontologies expressed in Web Ontology Language (OWL). It enables developers to browse or search the ontologies registered with the system by class or property names. In addition, they can submit a new ontology file
• RDF evoc (external vocabulary importer) is an RDF external vocabulary importer module (evoc) for Drupal caches any external RDF vocabulary and provides properties to be mapped to CCK fields, node title and body. This module requires the RDF and the SPARQL modules.

Not Apparently in Active Use

• ActiveOntology is a library, written in Ruby, for easy manipulation of RDF and RDF-Schema models, thru a dynamic DSL based on Ruby idiom
• Almo is an ontology-based workflow engine in Java supporting the ARTEMIS project; part of the OntoWare initiative
• ClassAKT is a text classification web service for classifying documents according to the ACM Computing Classification System
• Elmo provides a simple API to access ontology oriented data inside a Sesame RDF repository. The domain model is simplified into independent concerns that are composed together for multi-dimensional, inter-operating, or integrated applications
• ExtrAKT is a tool for extracting ontologies from Prolog knowledge bases.
• F-Life is a tool for analysing and maintaining life-cycle patterns in ontology development.
• Foxtrot is a recommender system which represents user profiles in ontological terms, allowing inference, bootstrapping and profile visualization.
• HyperDAML creates an HTML representation of OWL content to enable hyperlinking to specific objects, properties, etc.
• LinKFactory is an ontology management tool, it provides an effective and user-friendly way to create, maintain and extend extensive multilingual terminology systems and ontologies (English, Spanish, French, etc.). It is designed to build, manage and maintain large, complex, language independent ontologies.
• LSW – the Lisp semantic Web toolkit enables OWL ontologies to be visualized. It was written by Alan Ruttenberg
• OntoClassify is a system for scalable classification of text into large topic ontologies currently including DMoz and Inspec. The system is available as Web service. The software runs under Windows platform.

• Ontodella is a Prolog HTTP server for category projection and semantic linking
• OntoWeaver is an ontology-based approach to Web sites, which provides high level support for web site design and development
• OWLLib is a PHP library for accessing OWL files. OWL is w3.org standard for storing semantic information
• pOWL is a Semantic Web development platform for ontologies in PHP. pOWL consists of a number of components, including RAP
• ROWL is the Rule Extension of OWL; it is from the Mobile Commerce Lab in the School of Computer Science at Carnegie Mellon University
• Semantic Net Generator is a utlity for generating Topic Maps automatically from different data sources by using rules definitions specified with Jelly XML syntax. This Java library provides Jelly tags to access and modify data sources (also RDF) to create a semantic network
• SMORE is OWL markup for HTML pages. SMORE integrates the SWOOP ontology browser, providing a clear and consistent way to find and view Classes and Properties, complete with search functionality
• SOBOLEO is a system for Web-based collaboration to create SKOS taxonomies and ontologies and to annotate various Web resources using them
• SOFA is a Java API for modeling ontologies and Knowledge Bases in ontology and Semantic Web applications. It provides a simple, abstract and language neutral ontology object model, inferencing mechanism and representation of the model with OWL, DAML+OIL and RDFS languages; from java.dev
• WebScripter is a tool that enables ordinary users to easily and quickly assemble reports extracting and fusing information from multiple, heterogeneous DAMLized Web sources.