2 BACKGROUND
2.1 Semantic Web Services and BPM
Web Ontology Language for Services (OWL-
S) (Coalition, 2004) is an initiative to facilitate auto-
matic discovery, invocation, composition, and mon-
itoring of Web services through their semantic de-
scription. It augments BPEL (Business Process Ex-
ecution Language) processes with preconditions and
results to encode the side effects. A process can
be represented as a set of composed Web services.
BPM systems provide process modeling tools, execu-
tion engine, and key performance indicators (KPIs) to
monitor and measure end-to-end processes (in BPEL)
against operational targets. BPM address business
needs and design flexible processes that are based on
services, which can be implemented later with SOA
infrastructure. New and changed processes modeled
in the BPM may be implemented in the SOA infras-
tructure more rapidly because the SOA decouples the
described service from the specific implementation of
particular service. (Laukkanen and Helin, 2003) and
(Mandell and McIlraith, 2003) present methodologies
for semantic Web service composition.
2.2 Ontology and Knowledge Base
An ontology is a schema composed of concepts and
relationships among these concepts. A knowledge
base may use ontology to specify its structure (entity
types and relationships) and its classification scheme.
Ontology, with its instances, constitutes a knowledge
base that includes: (1) a set of concepts, properties,
and relationships among them, (2) high-level rules in
the form of constraints, (3) low-level rules defined in
semantic rule markup language (Horrocks, 2004), (4)
semantic service descriptions and. It builds the meta-
data needed by a program to understand its environ-
ment and status, reason about them, and then automat-
ically compose services to create new tasks, which in
turn can be scheduled with optimized resource while
complying with business policies and compliances.
Siemens MED group (Dickmann, 2006) has used
a methodological approach to define hierarchical
medical processes. (Emanuele and Koetter, 2006)
surveyed BPM and workflow technologies applied
in current healthcare systems. (ST Liaw and Lewis,
2006) proposed a modeling methodology to define
prescribing process using BPEL. Healthcare systems
can adopt BPEL processes, semantic Web services,
and ontology when dealing with workflows applied in
a hospital. By doing this, these systems can deliver
personalized medical workflows to patients, monitor
workflow status and optimize the flow in real-time,
and further coordinate these workflows to improve
the service they deliver. This paper aims to present
a system that delivers these features. In the rest of
the paper, Section 3 introduces a motivating medical
workflow scenario. Section 4 discusses the ontolog-
ical knowledge base. Section 5 describes the system
architecture with an emphasis on dynamic process or-
chestration. Section 6 presents methodology for pro-
cess monitoring, and Section 7 concludes.
3 SYSTEM OVERVIEW
3.1 A Hospital Scenario
Here we introduce a simplified healthcare workflow
with five participant roles:
RegistrationOfficer
,
Dis-
chargeOfficer
,
Nurse
,
Physician
, and
SupportStuff
.
For each role, there might be more than one partic-
ipant (instance). For example, one physician reviews
patient’s medical record, while another physician pre-
pares for the operation. The ADMIT phase starts when
a patient comes into a hospital and register in a wait-
ing list. An administrative assistant can check the rel-
evant data including insurance information, medical
history, patient address, emergency contact, etc. Then
the patient will go through the DETECT phase when a
healthcare professional like physician might do some
tests, such as blood test or X-ray test. The TREAT
phase follows and treat the patient’s disease for in-
stance by applying a surgery and/or a plaster. The
last phase is DISCHARGE when the patient leaves the
hospital and all relevant data including executed pro-
cesses is gathered for record and future diagnosis.
Due to uncertainty, it is difficult to handle all
events and emergencies in a hospital. From a pa-
tient’s view, patient may have to have the treatment
plan updated from time to time. This uncertainty and
dynamics exist because of: (1) newly come findings
from test, unexpected outcome from treatment, (2)
lack of resource, and (3) emergency. From a hospi-
tal’s view, a hospital may want to dynamically route
tasks among physicians and resources to provide bet-
ter care, timely response with minimized cost.
3.2 System Interfaces
Our workflow system provides role-based online ac-
cess to patients and hospital staffs. As shown in Fig 1,
a user can log into the system with the corresponding
roles. On his/her welcome page, there is a worklist
that shows all the pending tasks for the user as well as
the in-progress tasks. Using the worklist, the user can
PERSONALIZED MEDICAL WORKFLOW THROUGH SEMANTIC BUSINESS PROCESS MANAGEMENT
123