Showing posts with label java. Show all posts
Showing posts with label java. Show all posts

Wednesday, December 30, 2009

SOA, Web Services, BPEL, Human Workflow, User Interaction and Healthcare Systems


Lack of integration among legacy healthcare systems and applications means a continued reliance on manual processes that can introduce high risk errors into critical medical data. And isolated systems can compromise a provider's ability to follow an individual patient's care seamlessly from intake to treatment to aftercare.

While healthcare providers recognize that integration can help them achieve better service levels, many have been reluctant to proceed because of the critical nature of healthcare systems. But the approach to integration need not be a radical one of system rip and replace, nor does it have to precede through the development of system-by-system integration solutions.

Service Oriented Architecture (SOA) is a standards-based approach to integrating IT resources that can enable you to leverage existing assets, while at the same time building an infrastructure that can rapidly respond to new organizational challenges and deliver new dynamic applications. The SOA approach can help free application functionality from its underlying IT architecture and make existing and new services available for consumption over the network.

To derive a new value from existing services and go beyond simple point-to-point integration, you will need to combine and orchestrate these services in a business process. You will want to connect them in a coordinated manner, for example, have the result(s) from one service be the input to another service and have branching logic based on the outcome. Of course, you can use Java, C#, or another programming environment to call the services and manage the processes and data, but there is an easier, declarative way.

BPEL

An important standard in the SOA world is BPEL, or Business Process Execution Language, which serves as the glue to tie SOA-based services (Web services) together into business processes -- at least the portions that can be automated. The resulting BPEL process can itself be exposed as a Web service, and therefore, be included in other business processes.

The BPEL standard says nothing about how people interact with it, but BPEL in the Oracle Inc. BPEL Process Manager (to be discussed in my next post) includes a Human Workflow component (shown in the figure below) that provides support for human interaction with processes.



BPEL and User Interaction

I began an introduction to BPEL and human workflow towards the bottom of my December 14 post. Click here for a good deal more on this topic.

Humans can be involved in business processes as a special kind of implementation of an activity. To facilitate this, a new BPEL activity type called human task is required. From the point of view of the BPEL business process, a human task is a basic activity, which is not implemented by a piece of software, but realized by an action performed by a human being. In the drag-and-drop design pallet shown in the figure above, the actor of a human activity can be introduced into a BPEL process by using your mouse. A human activity can be associated with different groups of people, one for each generic human role.

People dealing with business processes do so by using a user interface. When human activities are used, the input data and output data must be rendered in a way that the user can interpret. More on this in upcoming posts.

Wednesday, November 25, 2009

Ontology-Based Software Application Development -- Java and .NET


Consider the following scenario: A programmer needs to read data from a database via the JDBC interface. The system administrator of the organization provides user name and password, which obviously need to be used in the process. Then, the programmer

1. Searches the entire API for a method call (or calls), which takes a database user name as an input parameter.

2. Has to understand how various API calls should be sequenced in order to go from the connection information all the way to actually receiving data from the database.

If the APIs are not semantically rich (i.e., they contain only syntactic information, which the programmers have to read and interpret), understanding, learning and using an API can be a very time consuming task.

For a discussion of how the application of ideas from the areas of "Knowledge Management" and "Knowledge Representation" -- The enrichment of purely syntactic information of APIs with semantic information -- will allow the computer to perform certain tasks that normally the human programmer has to perform, see

http://www.aifb.uni-karlsruhe.de/WBS/aeb/smartapi/smartapi.pdf


A similar semantification of Web services (Ontology-enabled Services) is being widely discussed and implemented today.




See, for example,

http://www.cs.vu.nl/~maksym/pap/Onto-SOA-WAI.pdf

and

http://www.computer.org/portal/web/csdl/doi/10.1109/AICT-ICIW.2006.141


A number of my earlier post have been about Protégé , the popular ontology development tool, and OWL, one of the main ontology languages. To continue that discussion, see

http://www.sandsoft.com/edoc2004/KnublauchMDSW2004.pdf


which discusses a realistic application scenario -- some initial thoughts on a software architecture and a development methodology for Web services and agents for the Semantic Web. Their architecture is driven by formal domain models (ontologies).

Central to their design is Jena, a Java framework for building Semantic Web applications. It provides a programmatic environment for RDF, RDFS and OWL, SPARQL and includes a rule-based inference engine.

Jena is open source and grown out of work with the HP Labs Semantic Web Programme.

For more on Jena, see

http://jena.sourceforge.net/documentation.html

Jena is a programming toolkit that uses the Java programming language. While there are a few command-line tools to help you perform some key tasks using Jena, mostly you use Jena by writing Java programs.

But, .NET developers have similar resources. See, for example

http://www.ic.uff.br/~esteban/files/sbgames09_Alex.pdf


for a development environment using Microsoft Visual Studio, the base language C#, and the graphical library XNA. Protégé has been used for designing the ontology, and the application uses the OwlDotNetApi library.

This 2009 work demonstrates a step-by-step implementation, from the definition of an ontological knowledge base to the implementation of the main classes of a strategy game. It aims at serving as a basic reference for developers interested in starting .NET development of ontology-based applications.