=Paper= {{Paper |id=Vol-34/paper-6 |storemode=property |title=A Scenarios Mediated Approach for Tacit Knowledge Acquisition and Crystallisation: Towards Higher Return-On-Knowledge and Experience |pdfUrl=https://ceur-ws.org/Vol-34/cheah_abidi.pdf |volume=Vol-34 |dblpUrl=https://dblp.org/rec/conf/pakm/Yu-NA00 }} ==A Scenarios Mediated Approach for Tacit Knowledge Acquisition and Crystallisation: Towards Higher Return-On-Knowledge and Experience== https://ceur-ws.org/Vol-34/cheah_abidi.pdf
 A Scenarios Mediated Approach for Tacit Knowledge Acquisition and
     Crystallisation: Towards Higher Return-On-Knowledge and
                             Experience

                                  Cheah Yu-N                                                   Syed Sibte Raza Abidi
                          School of Computer Sciences                                       School of Computer Sciences
                           Universiti Sains Malaysia                                         Universiti Sains Malaysia
                            11800 Penang, Malaysia                                            11800 Penang, Malaysia
                             yncheah@cs.usm.my                                                   sraza@cs.usm.my

                                                                                       Capital of an organisation. Put simply, Human Capital is
                                                                                       the knowledge, skills, experiences and intuitions possessed
                                                                                       by individuals in an organisation; Structural Capital refers
                                  Abstract                                             to knowledge that is embedded within an organisation
      The ‘Knowledge Age’ has fuelled the need to                                      operational system, i.e. an organisation’s processes, work-
      capitalise on organisation-wide Intellectual                                     flows, systems, policies and procedures; and finally Social
      Capital with the aim of gaining competitive                                      Capital refers to the organisation’s relationships with its
      advantage vis-à-vis a higher return-on-knowledge                                 network of customers as well as its network of strategic
      and experience. In this paper, we propose a novel                                partners and stakeholders. Of the three facets of
      tacit knowledge acquisition and representation                                   Intellectual Capital, in this paper we will focus on Human
      strategy using Scenarios based on the assumption                                 Capital.
      that tacit knowledge can best be explicated                                           Vis-à-vis Human Capital, the knowledge possessed by
      through controlled challenge situations. We also                                 an individual can be broadly differentiated between
      describe in detail, a knowledge crystallisation                                  Explicit Knowledge and Tacit Knowledge. Explicit
      algorithm that is used to refine the acquired tacit                              Knowledge can best be described as canonical knowledge,
      knowledge by modelling the natural mechanics of                                  i.e. knowledge formalised within databases, business rules,
      crystallisation and annealing. We conclude by                                    manuals, protocols and procedures and so on. Tacit
      asserting that our approach would further                                        Knowledge is non-articulated or non-canonical
      enhance organisation-wide performance through                                    knowledge, i.e. knowledge that does not manifest as rules.
      its superior quality and value-added delivery of                                 Rather it exists as the domain experts’ skills, common
      organisational services.                                                         sense and intuitive judgement whilst solving problems
                                                                                       [Che00]. The problem in many organisations today, we
                                                                                       believe, is that explicit knowledge has been given more
1 Introduction                                                                         prominence and that experience- and skill-rich tacit
                                                                                       knowledge is ineffectively or even hardly captured and
In today’s ‘Knowledge Age’, there is an ever increasing
                                                                                       utilised. This reliance on explicit knowledge may also
demand for more sophisticated Knowledge Management                                     result in rigid policies and thinking patterns that would
(KM) methodologies and techniques to provide the so-
                                                                                       hinder an organisation’s ability to gain competitive
called ‘next-generation business solutions’—solutions that
                                                                                       advantage and, thus, resulting in low return-on-knowledge
endeavour to provide a higher return-on-knowledge to the
                                                                                       and experience.
parent enterprise [Lan99]. It is widely acknowledged that
                                                                                            In this paper, we will focus on knowledge creation
an organisation’s competitive advantage and its capacity to
                                                                                       strategies [Non94], in particular the acquisition,
achieve higher return-on-knowledge is derived from the                                 representation and crystallisation of tacit knowledge with
effective operationalisation and management of its
                                                                                       the aim of allowing tacit knowledge to be utilised
Intellectual Capital. With definitions abound, Intellectual
                                                                                       effectively to gain competitive advantage with higher
Capital is generally described as comprising the Human
                                                                                       return-on-knowledge and experience. By using healthcare
Capital, Structural Capital, and Relational (or Social)
                                                                                       as an exemplar domain, we present a novel tacit
                                                                                       knowledge explication approach that purports the
The copyright of this paper belongs to the paper’s authors. Permission to copy
                                                                                       presentation of Scenarios pertaining to hypothetical
without fee all or part of this material is granted provided that the copies are not
made or distributed for direct commercial advantage.
                                                                                       problem situations to healthcare experts and in turn to
Proc. of the Third Int. Conf. on Practical Aspects of                                  record their ‘tacit’ problem-solving methodology and
Knowledge Management (PAKM2000)                                                        knowledge in solving the given problems. The specialised
                                                                                       knowledge extracting ‘scenarios’ are custom designed to
Basel, Switzerland, 30-31 Oct. 2000, (U. Reimer, ed.)
                                                                                       reflect atypical problems – i.e. not the kind of problems
http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-34/                  that can be solved by routine procedures. Rather, these are




Y.-N. Cheah, S.S.R. Abidi                                                                                                                      5-1
problems whose solutions may demand an interplay of             provoking domain experts to act and apply their
informal and ad hoc intuitive (or based on experience)          knowledge and skills to solve novel or atypical problems.
judgements with formal problem-solving strategy.                Such a provocation is to be achieved by repetitively
     The forthcoming discussion spans across the lifecycle      presenting domain experts ‘hypothetical’ Scenarios
of knowledge creation; initiating with a discussion on the      [Che00] pertaining to novel or atypical problems and then
proposed specialised knowledge extracting Scenarios vis-        observe and analyse the domain expert’s tacit knowledge-
à-vis mental models (as suggested in cognitive science          based problem-solving methodology and procedures. In
literature). We will discuss in detail, a scenario structure    this context, the proposed problem-specific scenario
and representation scheme that makes reference to the           presents domain experts the implicit opportunity to
notion of Meta-Scenario and its components. Next, we            introspect their expertise and knowledge in order to
will proceed to discuss scenario acquisition mechanisms.        address the given problem, to explore their ‘mental
Finally, we will present the latest extension of our work,      models’ pertaining to the problem situation and solution,
i.e. a technique for incremental knowledge refinement and       and finally to apply their skills and intuitive decision
categorisation through knowledge crystallisation which is       making capabilities. This sequence, allows tacit
based on the novel notion of Knowledge Nucleation and           knowledge to be ‘challenged’, explicated, captured and
Growth [Che00] – the formation of knowledge crystals by         finally to be stored. This strategy is in line with the notion
the amalgamation of multiple contextually/structurally          of ‘contrived’ knowledge acquisition techniques [Spe99,
similar scenario items. The work reported here purports a       Sha90].
synergy between artificial intelligence techniques (for              The novelty of our approach draws from the way
representation, reasoning and learning purposes) with           ‘hypothetical’ atypical problem situation (a problem-rich
existing concepts and practices in knowledge                    scenario that characterises the various elements and
management. In conclusion, we assert that our approach          peculiarities of a possible real-life situation) is derived.
would further enhance organisation-wide performance             Another novelty stems from the goal of the our strategy –
through its superior quality and value-added delivery of        i.e. to explicate tacit knowledge vis-à-vis charting out the
organisational services.                                        domain expert’s thought processes, or more appropriately,
                                                                mental models (as in cognitive science) for a set of well-
                                                                defined problems. Having introduced and discussed the
2 Tacit Knowledge Acquisition and                               rational behind the use of scenarios, we will now provide a
  Representation Using Scenarios                                description of scenarios.
Generally, traditional approaches, such as the interviewing
of domain experts, and subsequently observing and               2.1 Description of Scenarios
analysing their problem solving methodologies [Mor91],          A scenario, by itself, is a customised, goal-oriented
obtaining knowledge from reference materials and                narration or description of a situation, with a mention of
databases, and other techniques such as role playing,           actors, events, outputs and environmental parameters. Put
talkback, 20 questions, repertory grid, etc. only work well     simply, a scenario (a) depicts a sequence of distinct
to procure explicit knowledge. With this in mind, it is         actions that might be taken to accomplish a particular task;
widely contended that traditional strategies are ineffective    and (b) details the sequence of interactions – comprising
when it comes to acquiring an expert’s tacit knowledge.         exchange of messages and responses to intermediate
This is because traditional knowledge acquisition               outcomes – performed or experienced by entities to fulfil
techniques do not take into account the intrinsic origin and    the goal [Bee98]. In essence, a scenario is a collection or
composition of tacit knowledge during its acquisition.          sequence of hypothetical (but mimicking real) situations
    In view that tacit knowledge is highly intangible,          encountered by a domain expert, together with the
abstract and hidden, one can attribute its origin to be         intermediate responses/actions by the domain expert and
seemingly incorporated, embedded or interleaved with            henceforth describes one or more episodes or events of the
certain innate and essential skills – problem-solving skills,   scenario.
analytical skills and generalisation or abstraction skills.         From a cognitive science perspective, a scenario can be
We argue that it is the selective and systematic                deemed as a means to explicate the domain expert’s
manipulation of these innate skills, subject to the nature      mental model of the problem and its solution. Mental
and specification of the problem to be solved, that brings      models are not explicit and need to be inferred from by
into relief the so-called tacit knowledge that we seek to       putting them into action. This description of mental
capture. Furthermore, with regards to representation            models therefore relates closely to the qualities of tacit
schemes, the mention of schemata and mental models vis-         knowledge and its acquisition through the use of scenarios
à-vis tacit knowledge representation is of relevance here as    [Far88].
it posits that mental models are perceptions of the world.          From an artificial intelligence perspective, a scenario is
Thereby, an insight into tacit knowledge representation         very similar to a Case. However, the major distinction
(within our minds) can be achieved by understanding the         between the two is that a case is a real-life situation-action
cognitive make-up of such mental models.                        structure, whereas a scenario represents a sequence of
    In order to acquire tacit knowledge from domain             hypothetical situations carefully designed to draw out tacit
experts, we propose a strategy that is grounded in the          knowledge. Furthermore, cases are merely ‘frozen’
assumption that tacit knowledge can best be explicated by       snapshots of an episode with no apparent attempt to



Y.-N. Cheah, S.S.R. Abidi                                                                                                 5-2
capture significant temporal or sequential elements. On the      situational descriptions. Since tacit knowledge is both rich
contrary, as per our specifications, scenarios can manifest      in content and is also ‘deep rooted’, such contextual
a temporal nature whereby they can capture the sequence          information is imperative for the successful illustration of
of events as they may have occurred during a particular          the bigger picture, i.e. the sequence of episodes and
episode. In summary, we posit that a scenario is seemingly       events. To support our claim pertaining to the efficacy of a
a more apt representation of an episode or situation, as         scenario-based representation, we will now discuss in
compared to the traditional case-based representation.           detail the proposed generic structure of a scenario.
    Functionally, the proposed scenarios is akin to the
Scripts knowledge representation construct [Sch77],
However, we would like to point out that scripts are             3 Generic Scenario Structure and
somewhat limited in representing the context of the                Representation: An Overview
situation in its entirety. On the contrary, our proposed         Scenarios may be composed of four main components
scenarios cater for the clear representation of context vis-     [Sch97, Pot94]: Meta-Scenario, Scenario-Construct,
à-vis the provision for the linking of contextual documents      Episode and Event. For pragmatic reasons, scenarios are
to the sequence of events (described within the scenario).       represented by a four-tier scheme where Meta-Scenarios
We believe that the explicit characterisation of the full        are placed at the top level followed by Scenario-
context – i.e. a description of the social settings, resources   Constructs, Episodes and Events at the bottom level (see
and goals of the users [Nar92] – in describing a particular      Figure 1).
situation is an important consideration with regards to

                                META-SCENARIO
                                   Class ID        Class Name      Sub-Class List (1 to n)
      SCENARIO-
      CONSTRUCT
           ID / Description /    Trigger Event        Episode List (1 to n)       Concluding Event       Crystallisation
         Context / Timestamps                                                                               Factor


                                 EPISODE
                                    Episode ID       Episode Descr.       Event List (1 to n)

              EVENT
                  Event ID        Event Type         Actor       Object       Parameter-Value List (1 to n)

                                          Figure 1: The Scenario Structure outline.

     SCENARIO-CONSTRUCT
       Scenario ID: 990713.1520
       Scenario Description: First-aid CPR on adult male, 57 years of age. Bystander present.
       Location: Roadside
       Contextual Link: CPR, Elderly adult, First-aid
       Start Timestamp: 1520
       End Timestamp: 1538
       Trigger Event: EV0001
       Episode List Elements: EP0001, EP0002, EP0003, EP0004, EP0005
       Concluding Event: EV0016
       Crystallisation Factor: 24


                                                                                       PARAMETER-VALUE
     EPISODE                                     EVENT                                 LIST ELEMENT
       Episode ID: EP0001                         Event ID: EV0002                       Parameter-Value ID: PV0002
       Episode Description: Assessment            Event Type: Action                     Parameter: Shake
       Event List: EV0002, EV0003,                Actor: First-aider                     Value: Shoulder of Patient
       EV0004, EV0005                             Object: Patient
                                                  Parameter-Value List: PV0002



                Figure 2: Sample Scenario-Construct, Episode, Event and Parameter-Value List Element.




Y.-N. Cheah, S.S.R. Abidi                                                                                                  5-3
   The scenario storage medium – i.e. a Scenario Base –          A unique feature of the Scenario-Construct is the
adheres to the same scheme such that the various             Contextual Link field, which stores keywords to help
components of a scenario are stored in distinct              locate (through a search on specific document bases)
repositories. An exemplar Scenario-Construct with a          formal or informal documents containing contextual
sample Episode, Event and Parameter-Value List Element       information pertaining to the episodes and events of a
from a cardiopulmonary resuscitation scenario base are       particular scenario.
shown in Figure 2. We discuss, below, the four scenario          The Scenario-Construct also has a Crystallisation
components.                                                  Factor field that indicates how often the scenario was
                                                             accessed and judge as useful. The role of this field will be
3.1 The Meta-Scenario Component                              further discussed in Section 5.2.
The Meta-Scenario component serves to implement a two-       3.3 The Episode Component
level (class and sub-class) categorisation of scenarios.
Each category is called a class of scenarios and would       The Episode component stores details of individual
have a series of Sub-Class List Element (one for each sub-   episodes of a scenario (see Figure 5). Each Episode
class). Each meta-scenario could have the representation     comprises an Event List that stores the sequence of events
shown in Figure 3.                                           that make up an episode in a scenario.

                               Example                                                          Example
    Class ID                   CL0001                             Episode ID                    EP0001
    Class Name                 CPR                                Episode Description           Assessment
    Scenario Sub-Class         CPR for Adult                      Event List                    EV0002,
    Scenario List              990713.1520,                                                     EV0003,
                               990726.2053                                                      EV0004,
                                                                                                EV0005
                .
                .
                .                                                     Figure 5: Representation of an Episode.
    Scenario Sub-Class         CPR for Infant
    Scenario List              990804.1037                   3.4 The Event Component
                                                             The Event component stores details about individual
 Figure 3: Representation of a Class in a Meta-Scenario.     events. The representation for an Event is shown in Figure
    Shaded rows indicate a Sub-Class List Element.           6. There are three Event Types: Normative – events that
                                                             are expected to occur on a normal basis, Obstacle – events
3.2 The Scenario-Construct Component                         that hinder the progress of the task, and Action – events
The Scenario-Construct – a constituent of a scenario –       that define the course of action undertaken by an actor.
stores the description of individual scenarios. The
                                                                                                Example
representation for the Scenario-Construct is shown in             Event ID                      EV0002
Figure 4. Scenario-Constructs comprise a sequence of              Event Type                    Action
episodes that are arranged in chronological order to mimic        (Actor)                       First-aider
the temporal characteristics of the scenario. Such a              (Object)                      Patient
representation scheme ensures tractability in terms of the        Parameter-Value List          PV0002
sequencing (or chaining) of multiple episodes within a
scenario.                                                              Figure 6: Representation of an Event.

                       Example                                   The IDs of parameters and values of an event (in the
 Scenario ID           990713.1520                           form of Parameter-Value List Elements) are stored in the
 Scenario              First-aid CPR on adult male,          Parameter-Value List.
 Description           57 years of age. Bystander
                       present. Location: Roadside.
                                                                 In our scenario structure, episodes and events are
 Contextual Link       CPR, Elderly adult, First-            generic in nature until they are bound at the Scenario-
                       aid.                                  Construct (scenario base) level through the order in which
 Start Timestamp       1520                                  they are arranged and also through the effect of the Start
 End Timestamp         1538                                  and End Timestamps. Having formalised the scenario
 Trigger Event         EV0001                                representation, we would now discuss the scenario-based
 Episode List          EP0001, EP0002, EP0003,
                       EP0004, EP0005
                                                             (tacit) knowledge acquisition methodology.
 Concluding Event      EV0016
 Crystallisation       24
 Factor                                                      4 Tacit Knowledge Acquisition
                                                               Methodology: The Use of Scenarios
    Figure 4: Representation of a Scenario-Construct.        To facilitate organisational knowledge acquisition
                                                             activities, we have developed a tool called the Scenario
                                                             Composer [Che00] that facilitates domain experts to



Y.-N. Cheah, S.S.R. Abidi                                                                                            5-4
respond to a given scenario through the use of a series of          derived from existing solved scenarios by way of
electronic forms whose attributes correspond to a                   selecting a Point of Interrogation (POI) – a distinct
particular component of a scenario, i.e. Meta-Scenarios,            point in the scenario between two events of type
Scenario-Constructs, Episodes and Events. They prompt               Obstacle or Normative and an event of type Action.
domain experts to provide information or suggest values to          The result is a challenge scenario that is then
the various scenario-defining attributes presented in the           presented to the domain expert for the explication of
electronic form. Figures 7 and 8 are screenshots of the             his/her tacit knowledge (see Figure 9). The construct
Scenario Composer                                                   following the Challenge and POI captures the domain
                                                                    expert’s response, i.e. the explicated tacit knowledge.
                                                                   For practical purposes, once a scenario base is
                                                               sufficiently populated with knowledge – derived from both
                                                               solved and challenge scenarios – it can then be used for an
                                                               assortment of knowledge-driven activities. In the
                                                               healthcare domain, for instance, it can be used for
                                                               Healthcare Enterprise Modelling [CA99, Che99b].
                                                                   As it turns out, there is no restriction on the terms used
                                                               by the experts. Therefore, there is a need to integrate
                                                               domain ontologies with the Scenario Composer to enforce
                                                               a certain degree of standardisation. Without doubt, domain
                                                               ontologies hold an important place in our scenario-based
                                                               tacit knowledge acquisition mechanism. This is because
                                                               experts tend to use different, though similar, terms in
                                                               expressing themselves. The inconsistent use of terms
                                                               could cause serious problems especially when scenarios
                                                               are eventually used for inferencing purposes.
         Figure 7: Scenario-Construct screenshot.                  Ontologies, in our scenario context, could be integrated
                                                               or implemented in a pre- or post-input fashion. We can
                                                               also view it as being proactive or reactive. This means that
                                                               we could perform standardisation either before or after a
                                                               scenario is accepted into the scenario base. Ideally, this
                                                               should be done before a scenario is accepted to avoid
                                                               ambiguity in the event the expert is no longer unavailable
                                                               to provide clarification. Upon detecting a potentially
                                                               ambiguous terminology (such as those that are applicable
                                                               in more than one context, or those that have more than one
                                                               meaning), this pre-input mechanism would suggest
                                                               standardised terms for the expert to choose. In the post-
                                                               input version, the expert has little or even no control of
                                                               how this mechanism would standardise the terms used.
                                                                   The process of acquiring tacit knowledge and making
                                                               it explicit is only a small step in the ongoing efforts to
                                                               ‘create’ knowledge [Non94]. Moreover, the scenario base
                                                               in its ‘natural’ state is deemed inefficient in view that the
    Figure 8: Episode, Event and Parameter-Value List          scenario items are not categorised in such a way that
                   Element screenshot.                         would guide potential inferences by limiting an inference
                                                               engine’s search scope. Therefore, in the following
   Our novel scenario acquisition exercise distinguishes       sections, we would explore further on the modes and
between two types of scenarios:                                phases of knowledge creation leading to the refinement
1. Solved Scenarios: Scenarios that define actual              and categorisation of the scenario base through the
    situations/problems that have already been                 crystallisation of the explicated tacit knowledge.
    encountered and solved/addressed by domain experts.
    They are akin to traditional form-based cases that are
    acquired through traditional knowledge acquisition         5 Knowledge Crystallisation
    techniques. Scenario bases start out as having only
    solved scenarios.                                          Nonaka proposes four processes or modes that effectuate
2. Challenge Scenarios: Scenarios that represent atypical      the transformation between tacit knowledge and explicit
    situations and are posed to domain experts as a            knowledge [Non94]. These transformations span across
    challenge to their expertise. Challenge scenarios are in   five distinct phases, as shown in Figure 10. In a KM
    line with our contention that tacit knowledge is best      parlance, crystallisation is an integral process in the
    explicated when experts are required to solve atypical     creating concepts phase—it refers to the process where
    problems. In most instances, challenge scenarios are



Y.-N. Cheah, S.S.R. Abidi                                                                                                5-5
                                       Event ID     Event Type          Event Description
     Scenario          Trigger         EV0001       Obstacle            Patient has pain at centre
                       Event                                            of chest, lasting more than
     First-aid                                                          a few minutes, radiating to
     CPR on adult                                                       shoulders, neck and arms.
     male,             Episode         EV0002       Action              First-aider shakes shoulder
     57 years of                                                        of patient gently and shout           Challenge
     age.                                                               to ask if patient is
     Bystander                                                          alright.
     Present                           EV0003       Obstacle            Patient’s state of
                                                                        consciousness is
                                                                        unresponsive.                          POI
                                                    Action              First-aider calls for help.
                                                    Action              First-aider requests
                                                                        bystander to telephone
                                                                        Emergency Medical Services.
                                                    Action              Place patient in a
                                                                        comfortable position.              Expert’s
                       .               .            .                   .                                  Response
                       .               .            .                   .
                       .               .            .                   .                                     +
                       Concluding                   Normative           Patient’s pulse is 83 beats        ‘Tacit
                       Event                                            per minute and breathing at        Knowledge’
                                                                        15 breaths per minutes.
                                                                        Emergency Medical Service
                                                                        arrives 23 minutes after
                                                                        call made by bystander.

    Figure 9: A portion of a Challenge Scenario showing the Challenge, Point of Interrogation (POI) and the Domain
                                                  Expert’s Response.

               Socialisation      Externalisation     Internalisation         Combination



                  Sharing                                                                          Cross-
                   Tacit             Creating            Justifying            Building an        levelling
                 Knowledge           Concepts            Concepts              Archetype         Knowledge




                                           KNOWLEDGE BASE


                   Tacit       Conceptualisation     Explicit
                Knowledge/                          Knowledge/             Crystallisation
                Perspectives   & Externalisation     Concepts



             Figure 10: The Five Phase Model of the Organisational Knowledge Creation Process [Non95].

the various departments in an organisation, test the reality    the satisfaction of mutual constraints and unification
and applicability of the created concepts. As a                 amongst an ensemble of knowledge items, akin to the
consequence, knowledge that is proven effective, useful         process of arrangement of ions, as per chemical rules, to
and objective is maintained and perpetuated. Now, from a        form a crystal. We call the knowledge unit created by our
chemical parlance, crystallisation is interpreted to mean to    crystallisation process as a Knowledge Crystal.
‘solidify and internally arrange’.                                  A knowledge crystal can be viewed as a structure with
    In our work we intend to map the notion of chemical         a repetitive arrangement of scenario items in various
crystallisation to a knowledge creation context, whereby:       perspectives, with the objective refine the scenario base at
(a) knowledge items (scenario items in our case) mimic          the Scenario-Construct level. Basically, there can be two
molecules, ions or atoms in a supersaturated chemical           stages in knowledge crystal formation:
solution; and (b) the creation of concepts is achieved by




Y.-N. Cheah, S.S.R. Abidi                                                                                                 5-6
1.  Nucleation: The formation of a new child knowledge              Nucleation could be initiated when needed by the
    base in a heterogeneous (complex) knowledge base.           scenario base administrator or through an automated
2. Growth: The repetitive addition of free scenario items.      seeding process. This automated process follows an
    A prerequisite for both processes is supersaturation of     analysis of the knowledge base’s content and nucleation
scenario items. This means that crystallisation could only      occurs as often as needed depending on the requirements
occur when the knowledge density of a knowledge base            in creating child knowledge bases.
exceeds a predefined level [Bun96].
                                                                5.2 Growth
5.1 Nucleation
                                                                Growth occurs after nucleation is established. It is a
Nucleation begins with the presence of Knowledge Seeds          repetitive addition of scenario items to the nuclei
in the knowledge base and they are analogous to                 (knowledge seed) through the formation of links to the
impurities in a chemical solution. In the state of              nuclei. Depending on the knowledge seed, these scenario
supersaturation, these knowledge seeds form the nuclei for      items can be of the same structure and/or the same context.
the growth of knowledge crystals. Conceptually,                      Ideally, these links should be established between
knowledge seeds serve as a platform on which scenario           scenario items of similar structure and context, i.e.
items grow on.                                                  originating from a combination knowledge seed. Not only
    There are three types of knowledge seeds:                   would this fit closely to the original definition of chemical
1. Structural: The structural knowledge seed ensures that       crystallisation but it would also facilitate the
     only scenario items of the same structure may              implementation and operationalisation of emergent child
     interlink to it. The scenario base could potentially       knowledge bases. Child knowledge bases, comprising
     contain Scenarios, Episodes and Events that have           scenario items of similar structure and context, can
     different structural composition.                          therefore be envisaged as being more subject-focused in
2. Contextual: The contextual knowledge seed ensures            terms of their application domain and are also easier to
     that only scenario items of the same context may           manipulate in terms of query construction.
     interlink to it. It forms a knowledge crystal that is           Besides the knowledge seeds’ structural and contextual
     contextually uniform.                                      properties, we posit that the scenario items’ ‘temperature’
3. Combination (Structural and Contextual): This                or energy level (akin to that in simulated annealing
     knowledge seed ensures that only scenario items of         [Tay99, Kir83]) is an important factor in the growth stage.
     the same structure and context may interlink to it.        The notion of the energy of a scenario item could be
    The structure of a knowledge seed may consist of the        translated into the amount of activity surrounding a
following items (see Figure 11):                                particular scenario item, i.e. the number of times it was
1. Seed ID: States the identification number of the             referred or used by the system. We propose that when a
     knowledge seed.                                            scenario item is referred to and is frequently judged as
2. Seed Type: Determines if the seed is a Contextual or         useful, its accessibility is said to increase. Thus, its level of
     Structural knowledge seed or a Combination.                energy (or activity) decreases, i.e. for a scenario item to be
3. Context: States the context of the knowledge seed.           easily accessed, it should not ‘move’ too much. When the
     This will be used as the basis to attract scenario items   energy level of the scenario item decreases, its ability to
     and ensures that the knowledge crystal is contextually     crystallise or link to other scenario item increases (in line
     uniform.                                                   with thermodynamic principles). Conversely, when a
4. Scenario Structure: This field lists down the attributes     scenario item is referred to and is frequently judge as not
     (fields) of scenario items that can be bound to the        useful, its accessibility decreases and energy increases.
     Knowledge Seed. This ensures that only scenario            When this occur, it is less likely to bind with other
     items that are structurally the same can link to the       scenario items. These relations are summarised in Table 1.
     seed (as per Structural Knowledge Seeds).                       It should also be noted that a scenario item can only
5. Scenario Item List: This field lists down the Scenario       crystallise when its energy level drops below a certain
     IDs of all Scenario-Constructs that is linked to the       level, i.e. it is accessed and judged as useful frequently
     seed, i.e. crystallised.                                   enough. Therefore, a scenario item’s frequency of ‘useful’
                                                                access would need to exceed a predefined threshold before
                Example                                         it can crystallise.
Seed ID         KS0001                                               In order to facilitate the crystallisation process, a
Seed Type       Contextual
                                                                Crystallisation Factor (CF) field is added to the Scenario-
Context         First-aid
Scenario        [“Scenario ID”, “Scenario                       Construct representation (as mentioned in Section 3.2) to
Structure       Description”, “Contextual Link”,                store the number of times the scenario item was accessed
                “Start Timestamp”, “End Timestamp”,             and judged as useful. The CF would be decremented when
                “Trigger Event”, “Episode List”,                it is not judged as useful after a specified period of time. It
                “Concluding Event”]                             is possible for the CF to have a negative value in the event
Scenario        [“s.19990713.1520”, ...]
Item List                                                       that it is not useful for a long time.
                                                                     Upon completing the crystallisation process, the
        Figure 11: Structure of a Knowledge Seed.               resultant scenario base may contain (free) scenario items
                                                                as well as knowledge crystals. Free scenario items are the



Y.-N. Cheah, S.S.R. Abidi                                                                                                    5-7
                  Frequency of Access                Accessibility                        Energy Level                   Crystallisation
                          ↑                               ↑                                    ↓                               ↑
                          ↓                               ↓                                    ↑                               ↓

 Table 1: The Relation between Frequency of Access, Accessibility and Energy Level in the process of Crystallisation.

items of the original scenario base that did not bind to any
of the formed crystals. In fact, the resultant scenario base                     5.3 The Crystallisation Algorithm
changes from time to time depending on whether new
scenario items are added to the scenario base. Figure 12                         In an attempt to crystallise the scenario base, we have
illustrates the states before and after (or during)                              incorporated into the Scenario Composer, a knowledge
crystallisation.                                                                 crystallisation component. The steps executed by this
    In the Figure 12, two crystals are formed with two                           component in the crystallisation process are as follows (A
different types of knowledge seeds. Scenario Item ‘E’ is                         flowchart of the algorithm is shown in Figure 13):
shown linking with the crystal on the left as they are of                        Step 1: Create Knowledge Seed: A knowledge seed is
similar context and/or structure. Scenario Item X (a free                                 created by the domain expert or scenario base
scenario item) is on its own, as there are no crystals with a                             administrator using the representation detailed in
structure or context similar to its own.                                                  Section 5.1. For a newly created knowledge seed,
    With reference to Figure 12, crystallisation is shown as                              the Scenario Item List is an empty list.
an on-going repetitive process, executed in parallel even                        Step 2: Embed Knowledge Seed: The knowledge seed is
while more knowledge is accessed, shared and added into                                   ‘placed’ into a scenario base to initiate the
the scenario base. Functionally, crystallisation is                                       crystallisation process.
terminated momentarily when the density of scenario                              Step 3: Attract Similar Knowledge Units: Search the
items falls below the predetermined threshold.                                            scenario base for scenario items that have a similar
                                                                                          context and/or structure as the seed (depending on
                                                                                          the Seed Type field).

                             BEFORE
                                                                  SCENARIO BASE
                                          Scenario Item 1
                                                                        Scenario Item E
                                                                                                              Scenario Item 3


                                                                                    Scenario Item X
                                   Scenario Item A



                                                      Scenario Item 4                             Scenario Item D


                                                                                                      Scenario Item 2
                                         Scenario Item C
                                                                              Scenario Item B




                                                                CRYSTALLISATION
                             AFTER / DURING
                                                                  SCENARIO BASE

                                                            Scenario Item E                           Scenario Item 3


                                                                                                Scenario Item 1

                                   Scenario Item A          Scenario Item B



                                                                                                Scenario Item 2

                                   Scenario Item C          Scenario Item D
                                                                                                      Scenario Item 4


                                                                        Scenario Item X




                                          Knowledge Crystal/
                                        = Sub- or Child Scenario Base                                         = Knowledge Seed




                       Figure 12: The Scenario Base Before and After (or During) Crystallisation.




Y.-N. Cheah, S.S.R. Abidi                                                                                                                  5-8
Step 4: Select Most Similar Knowledge Unit: Among the             then added en bloc to the seed’s Scenario Item List.
         matched items, select the scenario item that has         However, we choose not to do this (at least for the time
         been frequently accessed and judged as being the         being) to mimic more closely the crystallisation process in
         most useful, i.e. having the highest CF.                 chemistry (which is incremental in nature). The
Step 5: Associate Knowledge Unit to Knowledge Seed:               incremental approach is also more time consuming.
         Link the selected scenario item to the knowledge         Nevertheless, from a chemistry point of view, the slower
         seed by way of adding the scenario item’s                the crystallisation process, the better the quality of the
         Scenario ID to the seed’s Scenario Item List.            crystals formed. However, at the moment we are not able
Step 6: Prioritise Selected Knowledge Units: Rearrange            to demonstrate any clear advantage for our choice.
         the Scenario Item List (of the seed) so that the CF          Step 6 allows the Scenario-Construct with the highest
         of the scenario items is in descending order.            CF to be at the head of the Scenario Item List. This
    Note that crystallisation begins after Step 2, provided       increases the efficiency of potential inferencing strategies
the scenario base is sufficiently populated by free scenario      as the most reliable or useful scenarios are considered
item. A user-defined threshold determines the number of           first. In the previous section, we proposed that the CF of
free scenario items that are needed to initiate the               the Scenario-Construct will be decremented, after a
crystallisation process.                                          predetermined period of time, if it is deemed not useful.
    In Step 4, as mentioned before, the selected scenario         This strategy ensures that outdated or less useful scenario
item must have a CF that exceeds a predefined threshold           items would eventually be among the last to be considered
before it can be linked to the knowledge seed in Step 5.          during inferencing.
    In Steps 4 and 5, the matched items could have simply
been sorted according to their CF in descending order and

                                                                      Start



                                           Step 1          Create Knowledge Seed



                                           Step 2              Select Scenario Base




                                                    No              Free Item
                                    Wait                          count exceeds
                                                                    threshold

                                                                          Yes

                                                    Search Scenario Base for Scenario items
                                           Step 3       with same context and/or same
                                                         structure as Knowledge Seed.



                                                    Among matched items, select Scenario
                                           Step 4      item that has the highest CF.




                                                    No           Crystallisation
                                                                 Factor exceeds
                                                                   threshold

                                                                          Yes

                                                    Link Scenario item to Knowledge Seed
                                           Step 5   by adding the Scenario item’s Scenario
                                                      ID to the seed’s Scenario Item List.



                                                    Rearrange Scenario Item List with the
                                           Step 6    CF of Scenario items in descending
                                                                   order.


                                  Figure 13: The Knowledge Crystallisation Flowchart.




Y.-N. Cheah, S.S.R. Abidi                                                                                                 5-9
After Step 6, if the number of free scenario items still      not useful. Garbage collecting can potentially be executed
exceeds the threshold, the process continues from Step 3.     in parallel with the existing crystallisation algorithm after
The crystallisation process stops momentarily when the        Step 3 where instead of selecting the most popular and
number of free scenario items drops below the threshold       useful scenario item for crystallisation, we select the one
only to resume when the threshold is exceeded.                that is least accessed and hence is removed from the
    We argue that the manner in which crystallisation is      scenario base. A detailed discussion of scenario-based
taking place by modelling chemical crystallisation does in    garbage collecting is beyond the scope of this paper.
fact conform to Nonaka’s original view where the              Nevertheless, we take this opportunity to highlight its
explicated tacit concepts are tested for reliability and      practicality and possibility.
applicability [Non94]. When a user accesses and evaluates         In general, we will like to point out that our approach
a particular scenario item, he/she is actually testing and    for knowledge crystallisation renders a more physical and
affirming its applicability and usefulness. Therefore, we     autonomous connotation such that the knowledge itself
argue that the more a scenario item is accessed and judged    undergoes a proactive automatic categorisation as
as useful, the more applicable the scenario item is deemed    compared to the original, more social and reactive
to be and more crystallised the concepts or scenarios.        approach. Note that our approach to crystallisation aims to
    The crystallisation algorithm can be adapted to           link scenario items to a knowledge seed in a crystal-
perform garbage collecting functions, i.e. the removal of     forming paradigm that ranks the scenario items in terms of
scenario items that prove to be very isolated cases and are   their applicability and usefulness.



        CONTEXTUAL_LINK+, START_TIMESTAMP,                           
        END_TIMESTAMP, TRIGGER, EPISODES+,                           
        CONCLUDING, CRYS_FAC)>                                       
                                   
                             ]>
    
                                                                                                                    OBJECT?, PARAMS_VALUES+)>
                                          
                                        
    
        #REQUIRED>                                                   
                          
                                                           (normative|obstacle|action) #REQUIRED>
                                                           IDREF #REQUIRED>
]>                                                               ]>


                                     Figure 14: Exemplar Scenario-Construct DTD.

                   
    First-aid CPR on adult male,                      Assessment
        57 years of age. Bystander present.                          
        Location: Roadside.                          
    CPR                           
    Elderly                                         
        adult                                  
    First-aid
    1520                      
    1538                              
                                         First-aider
                                      Patient
                                      
                                  
    
    
    
    24



                               Figure 15: Exemplar Scenario-Construct instance in XML.



Y.-N. Cheah, S.S.R. Abidi                                                                                             5-10
5.4 The Final Representation of Scenarios
Ideally, the explicated and crystallised tacit knowledge        References
would be stored in a representation language that is
portable, flexible and expressive. Currently, a likely          [Bee98]  G.W. Beeler, W. Rishel, A.M. Shakir and M.
choice of representation language is the Extensible Mark-                Walker. Message Development Framework
up Language (XML). The choice of XML is justified                        Version 3.1. Health Level Seven, Inc., 1998.
further by the fact that it is easily parsed and thus,          [Bun96] H.R.        Bungay       III.    Crystallization.
facilitates the translation of the XML document into other               http://www.esb.ucp.pt/~bungah/coag/ crys.htm,
representational language. Exemplar Document Type                        1996.
Definition (DTD) fragments for the Scenario-Construct,          [Che00] Y.-N. Cheah and S.S.R. Abidi. A Strategy for
Episode and Event representations and their XML                          Knowledge Acquisition and Representation: A
instances are shown in Figures 14 and 15 respectively.                   Case for Scenarios. 3rd Int. Conf. on The
                                                                         Practical     Application    of      Knowledge
                                                                         Management (PAKeM 2000), Manchester,
6 Concluding Remarks                                                     2000.
                                                                [Che99a] Y.-N. Cheah and S.S.R. Abidi. Healthcare
We believe that we have initiated a novel scenario-                      Knowledge Management Through Building
mediated approach to facilitate the capture and utilisation              and Operationalising Healthcare Enterprise
of the domain experts’ tacit knowledge, thereby leading to               Memory. In P. Kokol, B. Zupan, J. Stare, M.
the crystallisation of the acquired knowledge. Here we will              Premik and R. Engelbrecht (Eds.), Medical
like to point out that we do understand that the basis of our            Informatics Europe (MIE ’99), Ljubljana,
tacit knowledge acquisition approach is to some extent                   Slovenia, Amsterdam: IOS Press, 1999.
akin to traditional knowledge acquisition strategies, such      [Che99b] Y.-N. Cheah and S.S.R. Abidi. Evaluating the
as critiquing, role playing and simulation. However, we                  Efficacy of Knowledge Management and
believe that the novelty of our approach derives from the                Organisational Memory Toward Healthcare
following facts: (1) tacit knowledge is ‘invoked’ by not                 Enterprise Modelling. Workshop on Knowledge
mere interviewing the domain expert or document                          Management and Organizational Memories,
analysis, rather by subjecting the domain expert to solve                16th Int. Joint Conf. on Artificial Intelligence
‘controlled’ challenges (hypothetical’ atypical problem                  (IJCAI ’99), Stockholm, 1999.
situation) that itself are derived from existing solved real-   [Far88] M.U. Farooq and W.D. Dominick. A Survey of
life scenarios; (2) the scenario knowledge construct                     Formal Tools and Models for Developing User
represents the hierarchical make-up of tacit knowledge in                Interfaces. Int. Journal of Man-Machine
terms of an ensemble of distinct knowledge units; (3) the                Studies, 29:479-496, 1988.
acquisition of tacit knowledge follows the formal               [Kir83] S. Kirkpatrick, C.D. Gerlatt Jr. and M.P.
structural specification of the scenario, thereby ensuring a             Vecchi. Optimization by Simulated Annealing.
mapping of user-mediated knowledge items (with varying                   Science, 220:671-680, 1983.
degrees of specificity and context) to a scenario structure;    [Lan99] A. Lancini and E. Mercier-Laurent. Traffic
and (4) the crystallisation of acquired tacit knowledge in               Road Accidents Return on Experience.
terms of the chemical crystallisation process.                           Discovering,     Organizing     and     Sharing
                                                                         Knowledge to Minimize Risks and Costs in a
In this paper, we have discussed the said tacit knowledge                Mutual Insurance Company. 6th Int. Symp. on
acquisition and representation approach that attempts to                 the Management of Industrial and Corporate
capture the essence of expert-quality problem-solving                    Knowledge (ISMICK ’99), The Netherlands,
using scenarios. We have also seen how natural                           1999.
phenomena, such as crystallisation and annealing, can be        [Mor91] I. Morrison, B.A. Schaefer and B. Smith.
effectively adapted into Knowledge Management efforts                    Knowledge Acquisition: The Acquire®
to refine and categorise knowledge and to allow it to                    Approach. 1st Semi-Annual Conf. in Policy
dynamically evolve into scenario or knowledge bases that                 Making and Knowledge Systems, 1991.
are capable of providing relevant and up-to-date                [Nar92] B.A. Nardi. The Use of Scenarios in Design.
knowledge on-demand. The definition and development of                   SIGCHI Bulletin, October, 1992.
scenarios, the crystallisation algorithm and the Scenario       [Non94] I. Nonaka. A Dynamic Theory of
Composer are ongoing. Nevertheless, it is hoped that our                 Organizational       Knowledge         Creation.
methodology would lead to the improvement of                             Organization Science, 5(1):14-37, 1994.
organisation-wide return-on-knowledge and experience            [Non95] I. Nonaka and H. Takeuchi. The Knowledge-
resulting in the superior quality and value-added delivery               Creating Company. New York: Oxford
of organisational services.                                              University Press, 1995.
                                                                [Pot94] C. Potts, K. Takahashi and A. Anton. Inquiry-
                                                                         Based Scenario Analysis of System
                                                                         Requirements. Int. Conf. on Requirements



Y.-N. Cheah, S.S.R. Abidi                                                                                           5-11
           Engineering (ICRE ’94), Colorado Springs,
           1994.
[Sch77]    R.C. Schank and R.P. Abelson. Scripts, Plans,
           and Knowledge. In P.N. Johnson-Laird and
           P.C. Wason (Eds.), Thinking: Readings in
           Cognitive Science. Cambridge: Cambridge
           University Press, 1977.
[Sch97]    A.C. Schultz, J.J. Grefenstette and G.A. De
           Jong. Learning to Break Things: Adaptive
           Testing of Intelligent Controllers. In T. Baeck,
           D.B. Fogel and Z. Michalewicz (Eds.),
           Handbook of Evolutionary Computation,
           Bristol: IOP Publishing Ltd., 1997.
[Sha90]    N.R. Shadbolt and A.M. Burton. Knowledge
           Elicitaion. In J.R. Wilson and E.N. Corlett
           (Eds.), Evaluation of Human Work: A Practical
           Ergonomics Methodology, 321-345, London:
           Taylor and Francis, 1990.
[Spe99]    P.-H. Speel, N. Shadbolt, W. de Vries, P. H.
           van Dam and K. O’Hara. Knowledge Mapping
           for Industrial Purposes. 12th Workshop on
           Knowledge Acquisition, Modeling and
           Management (KAW ’99), Banff, 1999.
[Tay99]    T.      Tay.     Groping       the     Elephant.
           http://www.comp.nus.edu.sg/~tayhanbo/
           cs1305/index.html, 1999.




Y.-N. Cheah, S.S.R. Abidi                                     5-12