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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Enterprise Attention Management System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Darko Anicic</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nenad Stojanovic</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dimitris Apostolou</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>FDepartment of Informatics Decision Support Systems Lab, University of Piraeus</institution>
          ,
          <country country="GR">Greece</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>FZI Forschungszentrum Informatik</institution>
          ,
          <addr-line>Haid-und-Neu-Straße 10-14, 76131 Karlsruhe</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>We present a novel approach for proactive support of user in knowledge intensive organisations. Whilst once information was a scarce resource, nowadays all kinds and qualities of information are available. However human attention has become a scarce resource which is difficult to manage and support. Our attention management system proactively supports the user in dealing with processes, activities and tasks defined by a semantically-enhanced business workflow. Moreover the user is supported in reacting on changes respecting the users' context and preferences. The approach is based on an expressive attention model, which is realized by combining context-aware ECA rules with ontologies and an appropriate preference model. We present the system's architecture, describe its main components and present early evaluation results. Our system is particularly deployed in a use case related to eGoverment. Nevertheless the architecture we present is general, and may be used in all kind of information and knowledge systems where handling the user attention is of an important interest.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>Success factors in knowledge-intensive and highly dynamic business
environments include the ability to rapidly adapt to complex and changing situations
and the capacity to deal with large quantities of information of all sorts. For
knowledge workers, these new conditions have translated in acceleration of
working performance, multiplication of projects in which they are involved and
increased collaboration with colleagues, clients and partners. Knowledge workers
are overloaded with potentially useful and continuously changing information
originating from a multitude of sources and tools. A significant part of a
knowledge worker’s day can be occupied with searching and looking for information.</p>
      <p>In order to cope with changes of the business environment, the attention
of knowledge workers must be always paid on the most relevant information
sources. Indeed, a basic requirement of knowledge workers is to be up to date
with information while facing an information overload situation. In other words,
the issue is how to select those information resources whose reading will give
most benefits to the reader. Moreover, agility and proactive computer can be
useful in an environment of knowledge workers with overburdened memories:
The computer should know what a knowledge worker works with and show
him/her relevant information before they need them, in a kind of pre-search
function.</p>
      <p>
        According to [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], attention is defined as a ”focused mental engagement on
a particular item of information”. According to [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], attention is a process of
selection and selective processing, required because the brain has a limited
information processing capacity. In an enterprise context, attention management
refers to supporting knowledge workers focus their cognitive ability on a
particular organizational task and on the information resources required to accomplish
it. In particular support is required for searching, finding, selecting and
presenting the most relevant and up-to-date information without distracting workers
from their activities. Information retrieval systems have provided means for
delivering the right information at the right place and in right time. The main issue
with existing systems is that they do not cope explicitly with the information
overload, i.e. it might happen that a knowledge worker ”overlooks” important
information.
      </p>
      <p>
        The goal of attention management systems (AMS) is to avoid information
overload and to provide notifications about new and changed, relevant
information [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Moreover, the frequently changing environment requires not only very
effective systems for alerting knowledge workers that some relevant piece of
information has appeared or has been changed, but also effective recommendation
how to deal with these changes.
      </p>
      <p>Our approach for managing attention in a business environment is not just
to support receiving new relevant information proactively, but also to enable
relevant reaction on this information (i.e. on a change in general). Such an action
can be an already predefined workflow, but also ad-hock generated procedures
according to the currently available knowledge/experience. In that sense, our
approach of an enterprise Attention Management System (AMS) goes beyond
informing a user proactively that something relevant has been changed, toward
proactive preparing and supporting the user to react on that change. Our
approach puts forward a comprehensive reasoning framework that can trigger a
knowledge base in order to find out the best way to react on a change. We base
such a framework on a combination of reactive, deductive, and preference rules
and ontologies.</p>
      <p>The paper is organized as follows: in the second section we analyze
requirements and outline a framework for an enterprise attention management system,
in the third section we present the SAKE attention management model, in the
fourth section we present the architecture of the SAKE attention management
system encompassing various new functionalities to address relevant
attentionrelated issues. We conclude by suggesting outlets for future research and
development in information technology for the purpose of managing users’ attention
in knowledge-intensive environments.</p>
    </sec>
    <sec id="sec-2">
      <title>Requirements for AMS</title>
      <p>This section summarises the basic requirements for an Enterprise Attention
Management system:
1. Flexible modeling of information in order to enable focusing of attention on
different abstraction levels. For example, a user interested in information
about pets should be alerted for new information about domestic animals.
Another issue is modeling the usage of information by a community of users
in order to stimulate sharing of implicit knowledge. For example, users
looking for front tyre pressure must be proactively fed with the rear wheels’
pressure as most technicians are interested in both in most maintenance
situations.
2. Context-awareness in order to support a particular decision making process.</p>
      <p>
        For example, new law about animals triggers different alerts in different
regulation and business process areas.
3. Management of preferences for enabling efficient extraction of interesting
information. In particular, there is a need for an expressive formalism for
the description of preferences, including when to alert a user, but also how
to react on an alert.
1. Information represents all relevant chunks of knowledge that can be found
in the available information repositories and sources. In the business
environment of an organization, sources of information can be both internal and
external to the organization. Moreover, information can be represented
either formally (e.g. using information structuring languages such as XML) or
informally. Finally, information may be stored in structured repositories such
as databases that can be queried using formal languages or in unstructured
repositories such as discussion forums.
2. Context defines the relevance of information for a knowledge worker.
Detection of context is related to the detection of the user’s attentional state
which involves collecting information about users’ current focus of attention,
their current goals, and some relevant aspects of users’ current environment.
The mechanisms for detection of user attention that have been most often
employed are based on the observation of sensory cues of users’ current
activity and of the environment; however others, non-sensory based, mechanisms
also need to be employed to form a complete picture of the user’s attentional
state [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
3. Preferences enable filtering of relevant information according to its
importance/relevance to the given user’s context. In other words, the changeability
of resources is proactively broadcasted to the users who can be interested in
them, in order to keep them up to date with new information. Users may
have different preferences about both the means they want to be notified
and also about the relevance about certain types of information in certain
contexts. User preferences can be defined with formal rules or more
informally by means e.g. of adding keywords to user profiles. Moreover, even
when employing mechanisms capable of formalizing the users’ preferences,
a certain level of uncertainty about users’ preferences will always remain.
For this reason, dealing with uncertainty is an important aspect of
attention management systems. Equally important is the way preferences can be
derived: by explicitly specifying them or be learning techniques.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>The SAKE Attention Model</title>
      <p>This section presents an attention model which we have developed in SAKE3
project. Unlike other similar models, our attention model proactively supports
the user in reacting on changes respecting the user’s context and preferences. The
approach is realized by combining context-aware reactive rules, with ontologies,
and an appropriate preference model. Such an expressive attention model is the
basis of the SAKE Event-and-Context driven Attention Management System
(ECAMS).</p>
      <p>Figure 2 presents the conceptual attention model behind SAKE. The model
assumes that the interactions between users and internal information sources are
logged including the business context (e.g., business process) in which the
interactions happened. Some log entries can be defined as events that cause alerts,
which are related to a user, a problem domain and associated to a priority level.
3 SAKE - Semantic-enabled Agile Knowledge-based eGovernment is an EU funded
project (IST 027128): http://www.sake-project.org
Every alert invokes actions, that can be purely informative (i.e. an information
push) or executable (i.e. to execute a business process).</p>
      <p>Justification for using this new form of reactive rules in our attention
management system is elaborated in Section 4.2.</p>
      <p>Relevant events and actions are usually triggered by interactions taking place
in organisational systems, such as the SAKE workflow, Content Management
System (CMS) and the GroupWare System (GWS) or by external change
detectors. The later are implemented with the Change Notification System (CNS), a
component that can be configured to monitor web pages, RSS feeds and files
stored in file servers for any change or specific changes specified by regular
expressions (e.g. new web content containing the keyword ”sanitary” but not
”pets”).
4</p>
    </sec>
    <sec id="sec-4">
      <title>The SAKE Event-and-Context driven Attention</title>
    </sec>
    <sec id="sec-5">
      <title>Management System</title>
      <p>SAKE components which do not belong to SAKE ECAMS, while a more detailed
description of ECAMS is given through next subsections.</p>
      <p>Relevant events and actions are usually triggered by interactions taking place
in organisational systems, such as the SAKE WfM, CMS and GWS or by external
change detectors. The later are implemented with the CNS, a component that
can be configured to monitor web pages, RSS feeds and files stored in file servers.
The SAKE content management system (CMS) enables storage and provision of
content by:
– supporting the annotation of content with metadata as well as relations
between different content items;
– semi-automatic population of metadata using text mining methods; and
– realizing semantics-based search that retrieves content based on both
fulltext and metadata.</p>
      <p>The SAKE GroupWare system (GWS) supports information sharing and
creation by:
– supporting the annotation of the interactions between users;
– enabling identification of communities of practice from mining their
interactions and their specific vocabularies by social tagging; and
– searching for experts based on their profiles as these are created explicitly
and implicitly during their interaction with the system.</p>
      <p>The SAKE workflow management system (WfM) coordinates execution of users
tasks in SAKE system by:
– integrating GWS, CMS and ECAMS itself;
– strongly supporting business context management and sharing of the actual
user’s context.</p>
      <p>The SAKE Change Notification System (CNS) is a server based change
detection and notification system that monitors changes in the environment which
is external to SAKE. It can be configured to monitor web pages, RSS feeds and
contents of file servers. Users and the administrator can create new notification
queries for finding and displaying interesting changes. When creating a query,
users can define if they want to monitor a web page for any change or specific
changes in links, words or a selected section specified by a regular expression.
Moreover, users can select a topic of interest from a list. If new web page content
is added that is related to the topic or an RSS feed update contains
information related to the topic, then the user is notified. CNS relies on the services of
Nutch (http://lucene.apache.org/nutch/), an open source crawler, which is used
for fetching and parsing HTML documents, RSS feeds as well as resources in
other supported formats.</p>
      <p>In the remaining part of this section we describe the core components of the
SAKE Event-and-Context driven Attention Management System.
4.1</p>
      <sec id="sec-5-1">
        <title>SAKE Ontologies</title>
        <p>Conceptual information model in SAKE is realised via ontologies. For
example, ontologies are used to model change events, describe various information
resources, express user’s contexts and preference rules etc. In the following, we
further discuss roles of SAKE ontologies and outline their content.
Preference Ontology SAKE proactively delivers information resources (e.g.,
different documents and files) to a user. The resource delivery is realised in a
process of matching the business context on one side, and user’s preference rules
on the other side (preference rules are described in Section 4.3). Relationship
between the business context and user defined preferences is handled via the
validIn relation in the preference ontology, Figure 4(b) (e.g., particular preference
rule is validIn a certain context). The preference ontology 4(a) is typically
imported by another ontology which maps its own concepts to this ontology. More
specifically, by subclassing PreferredResource the importing ontology defines for
which type of resources (i.e., individuals) the user can define preferences.
Similarly, subclasses of ContextObject should be defined in order to indicate which
type of individuals the Context consists of (i.e., the business process, activity,
task, and the user).</p>
        <p>Furthermore, we differentiate between a RuntimeContext and a
PersistedContext. The RuntimeContext reflects the user’s current context and changes
dynamically with the user’s interactions within the system. This context may
be used to track user’s behaviour in the system. However, if a user’s interaction
is logged in the system as a persistent activity (e.g., the creation of a new
document) the user’s current context will be persisted (using the PersistedContext).</p>
        <p>The RuntimeContext and PersistedContex are utilised by the Context
Observer to extract the current business context, and hence, enable resource delivery
based on that business context.</p>
        <p>(a) Class hierarchy
(b) Class diagram</p>
        <p>Information Ontology The Information ontology (Figures 5 and 9(a))
contains the concepts and relations about information resources for which we want
to express preferences, such as documents and forum messages. On the top level
we have separated the domain concepts from value types. The FiletypeValue
class defines the different file types a file in the SAKE system can have.</p>
        <p>In the InformationSource sub-tree we differentiate between information sources
which are of an abstract nature (such as persons), external information sources
such as Web pages and RSS feeds, and information sources which physically
exists in the SAKE system, such as documents, forums or e-mails. We further
divided the physical information sources into CMS-specific and GWS-specific
entities. This FiletypeValue class represents the file type (indicated by the file
extension) of a document, for example PPT, PDF, DOC, etc. Note that one
subclass of filetype can describe multiple file extensions, such as JPG can be a
.jpg or .jpeg file.</p>
        <p>Log Ontology There are many sources of changes that can affect an information
resource, like adding, removing, deleting a new document or starting a new
discussion. The Log ontology (Figures 6(a) and 6(b)) is used for representing
these changes in a suitable format. There are four subclasses of Event: AddEvent,
RemoveEvent, ChangeEvent and AccessEvent. AddEvent is responsible for the
creation of new events, e.g. a new document has been added to the SAKE CMS.
It contains two subclasses: AddToCMSEvent, meaning the addition of a resource
to the CMS and AddToParentEvent, meaning the addition of an existing child
to a parent element, e.g. posting a new message to a discussion thread (Figure
7).</p>
        <p>RemoveEvent is dedicated to the deletion of the existing elements from the
system, like the deletion of a document from CMS. It consists of
RemoveFromCMSEvent, meaning the removal of a resource from the CMS and
RemoveFromParentEvent, meaning the removal of a child from a parent element, but
the child is still existent.</p>
        <p>ChangeEvent is responsible for the modification of an existing individual,
e.g., the change in the name of the author of a document. It consists of:
PropertyChangeEvent, meaning that some properties of an individual have changed
and IndirectChangeEvent, meaning a change caused by some other event.</p>
        <p>AccessEvent is dedicated to the access of an existing individual. It represents
a very broad class of events like reading a document, for which is very
complicated to define the semantics clearly. For example, did someone who opened the
document and closed it after five minutes, read the document or just opened,
considered it as not interesting, but forgot to close it immediately?</p>
        <p>We differentiate subclasses AddEvent and RemoveEvent by addition/removal
of resources to/from the CMS and by addition/removal of a resource to/from a
parent/child relationship using the isPartOf property. AddToCMSEvent is
fur(a) Class hierarchy
ther differentiated by either creating a resource within the SAKE system or
uploading an existing resource. For ChangeEvents, we distinguish between changes
of the resource’s properties (e.g. metadata) and changes which are caused by
some other event.</p>
        <p>Properties of an event are the resources the event relates to, the user who
originated the event, a timestamp when the event occurred, an optional
description of the event and a copy of the current runtime context. In the case
of ChangeEvents we add the names of the resource’s changed properties, and
optionally link to another event which caused this ChangeEvent.</p>
        <p>We do not hard-code the propagation of events from child to parent, instead
we define them in SWRL (Semantic Web Rule Language) rules4, such as:</p>
        <p>Default rules state that the addition/removal of a child object triggers a
ChangeEvent for the parent object. However, in order to be more flexible, we
could also state that the modification of a specific child object also causes the
modification of its parent. Note that in this way, we may use events to
specify more complex events (e.g., indirectChangeEvent). Those complex events are
created using SWRL rules and a number of built-in predicates supported by
KAON2 . Although realised in a declarative way, Complex Event Processing
(CEP) in SAKE is still limited, and it is subject of our future work.
Particularly, we will continue developing declarative CEP. The advantage of such an
approach is that definition of a complex event may easily be altered by changing
only a logical rule.Further on, inconsistencies in CEP are handled by means of
logic.</p>
        <p>Process Ontology While the other SAKE ontologies are rather general, the
process ontology (Figure 9(b)) is specific w.r.t the SAKE use case scenario. The
use case describes a knowledge intensive eGovernment organisation and
necessities help for knowledge workers in their daily business. The process ontology
describes main concepts related to various legal procedures in a municipality
administration and their relationship.
4.2</p>
      </sec>
      <sec id="sec-5-2">
        <title>Contextual Event Processing</title>
        <p>
          Reactive rules (such ECA and production rules [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]) are usually used for
programming rule-based, reactive systems, which have the ability to detect events
and respond to them automatically. However in many cases there is a gap
between current reactive rules that enable reaction to an event (change), and the
reality, in which reaction is relevant only in a certain context [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. As event-driven
reactive systems act autonomously, a central issue is the ability to identify
context during which active behaviour is relevant and the situation in which it is
required.
4 SWRL: http://www.w3.org/Submission/SWRL/
(a) Information Ontology
(b) Process Ontology
        </p>
        <p>Fig. 9. Ontologies (Class Hierarchies) for the SAKE Use Case.</p>
        <p>In SAKE, the business context is derived using a context observer. This
component links to enterprise systems (such as workflows) and extracts the current
business process, activity, and task the user is working on. The context describes
the situation which a user is currently present in, and is utilized for derivation
of information resources based on context-sensitive preferences.</p>
        <p>
          The business context in SAKE is formally described (see Section 4.1), which
in turn allows contextual reasoning with reactive rules. In classical reactive
systems [
          <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
          ] based on Event-Condition-Action (ECA) rules, reaction (i.e., action)
is triggered by an event, provided that the condition holds. Typically the
condition part provides the contextual background information. However this way of
expressing the context is rather limited. In our opinion, an automated reactive
system needs to be capable to deal with more complex business contexts and
situations, and hence needs to reason before undertaking any action [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]. This
is why we introduce ECCA rules where the context is explicitly represented5.
Moreover the context is formally realized by means of ontologies, and hence
allows for automated reasoning techniques to be applied.
        </p>
        <p>Depending on a user’s current working context (i.e., business process, activity
and task), the reasoner in SAKE ECAMS automatically searches for relevant
knowledge artifacts. In a nutshell of the process, the inference engine takes the
user’s business context (from the workflow), and gives back relevant information
resources. What is relevant to a user does not depend only on a particular
business context, but also on the user defined preference rules (described in
the following Section 4.3).
4.3</p>
      </sec>
      <sec id="sec-5-3">
        <title>Preference Rules</title>
        <p>A preference is an n-ary relation between a user, multiple resources, and a
preference value. Figure 10 shows how such a preference relation is formally modeled
using the preference ontology.</p>
        <p>
          Each preference (i.e., n-ary relation) is expressed as a deductive rule [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ],
represented in SWRL. Figure 11 illustrates an example of a preference rule: if
userA is in the processZ, then userA has preference of value 1.0 for documents
created in 2006. Among the preferred values, preferences include the business
context of the user, in order to support context-awareness of the whole system
(e.g., userA and processZ are related to each other by the same runtime context:
ctx.
        </p>
        <p>Utilising logical rules, for expressing context-sensitive user preferences, SAKE
features a very flexible preference model. One rule is used to assign different
5 the condition part in an ECCA rule is used for representing simple condition - one
that requires no reasoning (as complex computation) in order to be evaluated.</p>
        <p>Fig. 11. A Sample Preference Rule Expressed in SWRL
preference values to different information resources based on relevant criteria of
a particular user. Therefore every information resource may be assigned with
different preference values by different preference rules (i.e., by different users
and/or business contexts). Another flexibility of the SAKE preference model
comes from an implicit representation of preferences. Since preference values are
not pre-computed and persisted in the system, just adding one preference rule
may significantly influence the whole preference model. Also adding a common
preference to the SAKE preference model (i.e., a preference valid for all users)
may be as easy as adding only one preference rule. Moreover updating existing
resources, or adding new ones, does not mess up all previously created preference
values. In this way, a user is given a great freedom to create particular
preferences for particular processes, activities, tasks, and even to aggregate multiple
preference values for one resource into a final score.</p>
        <p>The Preference Editor supports creation of preference rules by providing a
GUI for step-wise, interactive rule development, as presented in Figure 12. The
user starts with selecting what kind of resources (i.e., file, forum, workspace,
email etc. that is a subclass of pref:PreferredResource) s/he wants to define a
preference for. This information is specified in the information ontology (Figure
9(a)), and is represented as a variable ?res in Figure 11. The preference rule, is
than, further extended narrowing down the preference criteria in several
subsequent steps (possible introducing new variables). For each of these steps, SAKE
reasoner is used to find out the list of possible properties or property values that
are available. Further on, values entered by a user are syntactically checked out
(e.g., for the data type). In this way, the Preference Editor eases the process of
creating valid and consistent preferences.
Preference rules, created by the editor, are serialised to its SWRL
representation and stored in the preference ontology. Finally, preference rules may also
be removed (or updated) using the Preference Editor.
5</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Conclusion and Future Work</title>
      <p>In this paper we presented a novel approach for managing user’s attention. The
approach is realised through a reactive system that manages not only alerts to
a user when something has been changed, but also supports the user to react
properly on that change. In a nutshell, the corresponding system is an
ontologybased platform that logs changes in internal and external information sources,
observes user context and evaluates user attentional preferences represented
reactive rules.</p>
      <p>The presented system is currently under deployment in a real-environment.
We have developed the first prototype, however results from the formal
evaluation are still missing.</p>
      <p>
        Future work of the attention management framework, presented here, will go
toward a logic based event-driven reactive system (see [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]). Such a system will
be fully automated and controlled by a state-changing logic. Furthermore the
system will allow new reasoning services, e.g. reasoning about conflicting business
contexts and situations, as well as, causal relationships between complex events,
conditions, and actions.
      </p>
    </sec>
  </body>
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