=Paper= {{Paper |id=Vol-2969/paper25-FOMI |storemode=property |title=Flight Procedures Description Using Semantic Roles |pdfUrl=https://ceur-ws.org/Vol-2969/paper25-FOMI.pdf |volume=Vol-2969 |authors=Cédric Tarbouriech,Denys Bernard,Laure Vieu,Adrien Barton,Jean-François Éthier |dblpUrl=https://dblp.org/rec/conf/jowo/TarbouriechBVBE21 }} ==Flight Procedures Description Using Semantic Roles== https://ceur-ws.org/Vol-2969/paper25-FOMI.pdf
Flight Procedures Description Using Semantic Roles
Cédric Tarbouriech1 , Denys Bernard2 , Laure Vieu1,3 , Adrien Barton1,4 and
Jean-François Éthier4
1 Institut de Recherche en Informatique de Toulouse (IRIT), Université de Toulouse & CNRS, France
2 Airbus, Architecture & Integration IIVD, Blagnac, France
3 Laboratorio di Ontologia Applicata, ISTC-CNR, Italy
4 Groupe de Recherche Interdisciplinaire en Informatique de la Santé (GRIIS), Sherbrooke University, Québec, Canada



                                      Abstract
                                      This paper presents an ontological analysis of flight procedures. We aim at representing participants of
                                      processes described by such procedures and what roles they play. We re-use the Process Specification
                                      Language (PSL) by re-interpreting it as dealing with informational entities describing processes rather
                                      than process universals. The identification of roles is based on the analysis of flight manuals (FCOM).
                                      The instructions were analysed to find out patterns that supported the construction of an ontology of
                                      instructions.

                                      Keywords
                                      flight procedure, semantic roles, FCOM, PSL, procedure




1. Introduction
For a virtual assistant to be able to help a person execute some process, it is necessary to have
a representation of the sequence of steps involved and the participants (living beings, objects,
informational entities, etc.) involved, among other entities. To do so, the virtual assistant can be
based either on a representation of a particular of procedure (a procedure is an informational entity,
e.g. the text of a chocolate cake recipe) or on a representation of an universal of executions of this
procedure (an execution is a process, e.g. baking a chocolate cake following the recipe). Here, we
chose to use the procedure particular because of the challenges that would be raised by the other
solutions. Indeed, using universals would expose us to a common problem of structural universals
(see Section 3.1.1). Moreover, two particular executions of the same procedure are likely to differ
to some extent (they may even not follow appropriately some parts of the procedure): they are
typically realised at different times, involving different particular participants, and under different
conditions. For these reasons, the present work will focus on the representation of procedures.
   A procedure presents various features that need to be represented, and refer to: the temporal
structure of the directed actions (the order in which the actions must be done); the participants

FOMI 2021: 11th International Workshop on Formal Ontologies meet Industry, held at JOWO 2021: Episode VII The
Bolzano Summer of Knowledge, September 11–18, 2021, Bolzano, Italy
" cedric.tarbouriech@irit.fr (C. Tarbouriech); denys.bernard@airbus.com (D. Bernard); laure.vieu@irit.fr (L. Vieu)
~ https://www.irit.fr/~Cedric.Tarbouriech/ (C. Tarbouriech); https://www.irit.fr/~Laure.Vieu/ (L. Vieu)
 0000-0001-8119-7826 (C. Tarbouriech); 0000-0002-0131-4795 (D. Bernard); 0000-0003-0303-0531 (L. Vieu);
0000-0001-5500-6539 (A. Barton); 0000-0001-9408-0109 (J. Éthier)
                                    © 2021 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
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(the endurants involved in the action: human beings, objects, etc.); the conditional structure (some
actions must be done only under some circumstances); the mereological structure (some complex
actions may be decomposed into more basic ones), etc.
   This paper presents a work inspired by PSL (Process Specification Language) [1], a framework
to describe the structure of universals of executions. Even though the work on which it is based
targeted multiple features of procedures, this paper focuses on the integration of participants in the
representation. PSL uses universals of processes (called “activities”) and particulars of processes
(called “activity occurrences”). In this paper, the activities are reinterpreted as informational
entities describing such processes, and thus as endurants rather than universals of perdurants. We
also extend PSL to represent a variety of participants1 by introducing semantic roles, which are
relations between activities and participants.
   The proposed ontology2 is based on a corpus created for this work, that contains procedures
from flying procedure manuals named “FCOMs” (The acronym FCOM stands for Flight Crew
Operating Manual). The resulting representation framework is meant to be used in applications
such as in-flight virtual pilot assistants.


2. Methods
The first step of the integration of semantic roles into PSL was to get a good overview of what
kinds of roles are used in instructions, and under which modalities. Therefore, the first task was
the creation of a corpus of instructions, based on FCOMs. This corpus was then analysed with the
aim of identifying patterns of instructions, where a pattern is the combination of roles involved in
an instruction. Instructions sharing the same pattern were then clustered to make a taxonomy of
the piloting activities. In this section, we describe how the corpus was built and present PSL on
which our proposal builds.

2.1. Creation of the Corpus
2.1.1. Presentation of FCOMs
FCOMs are manuals of all the procedures that pilots may need, whether during regular situations
(e.g. take-off and landing procedures) or emergencies. There are various FCOMs, depending on
the airplane or the company. The work presented in this paper uses all the procedures of a generic
A350 FCOM [2]. The procedure partly presented in Figure 1 is a part of the Take-off procedure,
namely the Thrust Setting sub-procedure, and it will be used as an example in the paper.
   Each (elementary) instruction line has at least two parts, separated by a row of dots. A synthetic
representation of an instruction is presented in Figure 2. The challenge is an endurant involved
in the action, such as a tool (THRUST LEVER), a person or a group of people (CREW) or a
message (“TAKE-OFF”). The response part is an indication of what to do on the object. It may



    1 Since activities are reinterpreted as informational entities, the participants participate in the processes described

by those activities, and not in those activities.
    2 The ontology is available on the following Github repository: https://github.com/CedricTarbouriech/FPO.
Figure 1: Excerpt of the A350 Take-Off procedure (image lightly edited to remove irrelevant informa-
tion).


be an action (ANNOUNCE) or a state (HALF FORWARD). The agent3 gives an indication about
who is supposed to do the action. It may designate a single person (PF4 ) or a group (BOTH
PILOTS). Some instructions have a free-text paragraph, the comment, which indicates important
information about the instruction execution. The agent or the comment may be missing. The first
instruction in Figure 1 is therefore understandable as “Agent PF must announce the take-off”.




Figure 2: Representation of an instruction


   The temporal structure of the procedure is usually indicated by the order of the instructions.
However, some instructions can have annotations to indicate that they can be executed at any
time. The conditional structure is expressed using bullets.5 All the conditioned instructions are
indented under the condition label. A conditional block is visible in Figure 1: the bullet is the
condition, all the lines below it are conditioned by it. The mereological structure is based on
redirection to other common procedures (not illustrated in Figure 1). These common procedures
are written as appendices and may be referenced anywhere in the FCOM.

2.1.2. Instructions Extraction
FCOMs are XML-based documents, i.e. the manuals are generated from the procedures structured
in XML. Besides XML offering a certain level of structuration (as shown in Figure 3, the
     3 Note that “participant” and “agent” refer to two different things: the former refers to any entity that is involved

in the action, whereas the latter always refers to the entity performing the action. The agent is a kind of participant.
     4 “PF” means “Pilot Flying”. The other pilot is called “PM”, for “Pilot Monitoring”.
     5 Different bullet styles are used to indicate exclusive or non-exclusive conditions.
           < a c t i o n l i d = " P . 0 0 0 0 6 6 0 7 . 0 0 0 1 0 0 1 . 0 0 8 " crm− f c = " PF " >
               < cr − a c t i o n code = " 0 0 0 0 6 6 0 7 . 0 0 0 1 0 0 1 . 0 0 4 " >
                   < c h a l l e n g e >TAKEOFF< / c h a l l e n g e >
                   < response >ANNOUNCE< / response >
               < / cr − a c t i o n >
           < / action >

Figure 3: The first instruction of the Figure 1 encoded in the XML file (code lightly edited to remove
irrelevant information).


instruction parts are separated using different XML elements), the various parts of instructions
(challenge, response, etc.) are mainly written in plain text. Therefore, there are small variations
requiring a normalisation of the corpus.
   To have a usable corpus, the parts of the instructions have to be extracted. Among the four
parts presented in Figure 2, only the challenge and the response were extracted. The comment
was left apart because, in contrast to the other elements, it is not just constituted by a word or
two, but by one or more sentences. Thus, extracting information from it would require Natural
Language Processing techniques that were not in the scope of this work. However, in rare cases,
comments were used to better understand instructions. The agent was also left apart. Procedures
are executed by human beings, hence we consider that every instruction has at least one agent. If
the instruction involves multiple persons, the agent is considered to be the group of those persons.
So, there is at most one agent. Therefore, for each instruction, there is exactly one agent. As there
is such a role for every instruction, we did not extract the agent parts from the FCOM. The two
extracted elements were grouped and will be called a “pair”.
   The normalisation consisted mainly of typographic modifications. Indeed, there were some
typographic variations, such as upper or lower case being used in similar contexts, or the inclusion
of hyphens or spaces. Those normalisations were made semi-automatically. The data were
explored manually. Many instructions were rewritten under standardised forms, which were
chosen among the variations, mainly by selecting the most frequent one. 1485 unique pairs of
challenge and response were extracted.
   Once the normalisation process was performed, the corpus was reduced by selecting some
pairs. Two different sets of pairs were selected. The first selection set contains all the pairs that
appear five times or more in the document, i.e. 144 pairs (approximately 10% of the corpus). It
ensures that the remaining pairs were highly representative of what could be found in the FCOM.
The second set contains also 144 randomly selected pairs among the remaining pairs. It ensures
that the pairs considered are diverse enough. To ensure higher diversity, a condition was added:
to be selected in the second set, a pair must have a response part that is not in the first extracted
response set. Finally, once both sets are merged, the post-selection corpus contains 288 pairs,
which is approximately 20% of the 1485 pairs of the pre-selection corpus.
   The corpus was analysed to identify patterns and involved roles. Results are exposed in 3.1.
2.2. Presentation of PSL
The Process Specification Language ontology provides a description framework for manufacturing
processes. It is described by the ISO standard 18629 [3]. PSL has a semantics based on first-order
logic and an OWL and SWRL axiomatisation.6 The version of PSL used for this work is described
in Grüninger’s 2009 paper [1]. PSL proposes core theories and definitional extensions. The first
core theory, which is extended by other core theories, is PSL-Core. Even though the other core
theories are consistent with PSL-Core, they may be mutually inconsistent. The core theories used
in this work are Tpsl_core and Tsubactivity .
   The Tpsl_core theory defines the basic classes and relations used in all the PSL environment,
presented in Table 1. This theory defines four classes, all disjoint, two relations and two functions,
three of them being time-related. Within PSL, each activity is a reified universal that is an instance
of activity. Temporal relations only apply to occurrences.

Table 1
Vocabulary of Tpsl_core [1].

              activity(a)                  a is an activity
              activity_occurrence(o)       o is an activity occurrence
              timepoint(t)                 t is a timepoint
              ob ject(x)                   x is an object
              occurrence_o f (o, a)        o is an occurrence of a
              begino f (o)                 the beginning timepoint of o
              endo f (o)                   the ending timepoint of o
              be f ore(t1 ,t2 )            timepoint t1 precedes timepoint t2 on the timeline

   The Tsubactivity theory introduces the class Primitive, subclass of Activity, and the relation
subactivity (see Table 2). These two are used to define a mereological structure over activities, in
which Primitive instances are the atomic elements. The axioms of the theory make subactivity a
discrete partial ordering. Except for the discrete feature of the ordering, this is the most basic
mereology possible. This theory does not allow the characterisation of the relationship between
the occurrence of a complex activity and occurrences of its subactivities. To do so, the core theory
Tcomplex is needed.

Table 2
Vocabulary of Tsubactivity [1].

                 subactivity(a1 , a2 )   a1 is a subactivity of a2
                 primitive(a)            a is a minimal element of the subactivity ordering

   Another theory named Tactors was introduced by Katsumi and Grüninger in 2015 [4]. This core
theory introduced actors and relations between actors, activities and activity occurrences. The
relation performs between actors and activities is intended to correspond to the semantic role
agent (see below); no other semantic role is considered. However, as far as we know, this theory
is only cited in the 2015 paper and never exploited after that. Therefore, we ignored it for this
    6 CLIF and OWL files are accessible at https://github.com/gruninger/colore/tree/master/ontologies.
work. It is worth noting that this work is complementary to ours, as it creates relation between
activities and activity occurrences.


3. Results
3.1. Analysis of the Corpus
3.1.1. Instructions
We assume that for the same kind of instructions, the same roles are involved. Therefore, the pairs
were grouped by the response, which is generally a verb. A class of instructions was associated
to each cluster, and named using a verb, as shown in Table 3. This verb is not necessary the
response. Indeed, sometimes, it was relevant to group clusters using a more generic verb. When
such a clustering was done, the classes associated to the clusters were related by subclass relation.
For example, the clusters of pairs for which the response were “Alert” or “Announce” were
grouped under the label “Communicate”, and the classes Alert and Announce are subclasses of
Communicate.

Table 3
Description of classes based on clusters
      Identifier        Description                                          Examples
         Act7           Physically act on something. Various sub-            “Increase thrust.”, “Start chronome-
                        classes exist, such as: Push, Pull, Press.           ter.”
        Fetch           Fetch a parameter’s value from a sensor              “Check if oxygen masks are cor-
                        or another agent. Two subclasses exist:              rectly stowed.”, “Monitor fuel con-
                        Check and Monitor                                    sumption.”
   Communicate         Give information to a human or a group “Announce take-off to passengers.”,
                       of humans. Various subclasses exist, as: “Order brace for impact.”
                       Alert, Order, Announce.
         Set7           Make sure that an object is in a given               “Set the thrust levers to 25%.”, “Re-
                        state.                                               tract flaps.”


   By a first non-systematic exploration of the corpus, we identified two types of instructions:
elementary instructions and meta-instructions. An elementary instruction is an instruction stating
that an agent must do some action. A meta-instruction is an instruction that states something
about another instruction or group of instructions, such as modifying the deontic structure (e.g.,
allowing or recommending some action: “Consider landing”), or defining a specific protocol that
must be followed each time an action of a given type will be executed. Their range vary, from a
    7 Even though Act and Set look similar, Set is not a subclass of Act. Act is a class of instructions that aim at

directing physical actions (push, pull, etc.) on objects (button, lever, etc.), whatever the state of these objects is. Set
is a class of instructions that aim at directing actions on objects setting them in some specific states. If the object is
already in that state, then no action is performed (except checking the object’s state). We could consider Set to be the
sum of a Fetch-type action and an Act-type action, conditionally applied depending on the result of the Fetch-type
action. However, we used Set as it is considered a simple enough instruction in the FCOM.
single instruction to all subsequent instructions in the procedure. In this work, meta-instructions
were not analysed, and therefore various clusters that contain meta-instructions were left out of
the analysis, such as “Consider landing” or “For directional control, use rudder”. Representing
such meta-instructions requires a more complex representation of instructions. Indeed, most
instructions are implicitly considered to be orders, and therefore must be executed by the pilots;
but in “consider landing”, the verb “consider” shows that the pilot could, after deliberation,
choose to ignore it. “For directional control, use rudder” establishes a way to proceed for precise
directional control tasks. It is not an instruction executed once, but it applies to all following
instructions that concern directional control.
   Let’s take an example: consider the procedure “1) Press the button, 2) Flip the lever, 3) Press
the button”. This procedure has three instructions: 1) and 3) are two utterances of the very same
sentence (sequence of words), and 2) is an utterance of another sentence. In that case, PSL will
use two particulars, instances of Primitive: pressButton and flipLever. The repetition of “Press
the button” will be expressed with activity occurrences linked to pressButton with the relation
occurrence_of. What we want to do is to describe this repetition at the activity level instead of
the occurrence level. For example, we want to use activities in temporal relationship. However,
if we do this in PSL, the very same particular will be involved in multiple relations. Those
relations could be incompatible with each other: stating that pressButton is temporally before
and after flipLever makes no sense. This problem is one of the problems encountered while
using structural universals.8 To avoid it, we want each instance of Activity to represent a unique
instruction. In this work, each utterance is a particular, and each sentence is associated to one of
the subclasses of Primitive. In our example, a class Press, subclass of Primitive, would exist and
have both utterances 1) and 3) as instances. To summarize, in PSL, activities are reified universals
of processes, but in this paper, they are particulars of informational entities. This is a shift in the
interpretation of PSL.

3.1.2. Semantic Roles
In this work, patterns of semantic roles are important to create clusters of instructions. Grouping
instructions by role patterns enables to classify more precisely the instructions. The participants
(other than the agent) were mainly mentioned in the challenge part. It is worth noting that a
challenge could mention multiple participants (e.g. “Advise cabin crew and passengers.”) and
that some of the participants were not mentioned in the instruction, but in the comment.
   To represent the participation of an entity in an action, semantic roles were used. For example,
in the FCOM instruction “Agent PF must announce the take-off”, “PF” refers to the entity doing
(or which will do) the action, namely the agent, and “the take-off” refers to the message (that the
take-off is about to occur) to be communicated during this action, namely the theme. There has
been various proposals on roles descriptions. We based our work on the ISO norm 24617-4:2014
[10], which defines semantic roles, as presented in Table 4. Among the large variety of roles,
only few were chosen, based on their relevance for our problem.
   We completed those semantic roles with the EndLoc role from the work of Jezek et al. (2014)
on Senso Commune [11]. We then redefine the roles to make them better match our needs. This
    8 About structural universals, see Lewis (1986) [5], Armstrong (1986) [6], Bigelow (1986) [7], Fisher (2018) [8]

and Garbacz (2020) [9].
Table 4
Relevant semantic roles from ISO norm 24617-4:2014
               Role      Description
               Agent     Participant in an event who intentionally or consciously initi-
                         ates an event, and who exists independently of the event.
               Goal      Participant in an event that is the (non-locative, non-temporal)
                         end point of an action; the participant exists independently of
                         the event.
              Patient    Participant in an event that undergoes a change of state, loca-
                         tion, or condition, is causally involved or directly affected by
                         other participants, and exists independently of the event.
              Source     Non-locative, non-temporal starting point of an event. The
                         source exists independently of the event.
              Theme      Participant in a state or an event that (a) in the case of an event,
                         is essential to the event taking place, but does not have control
                         over the way the event occurs and is not structurally changed
                         by the event, and (b) in the case of a state, is characterized as
                         being in a certain position or condition throughout the state,
                         and is essential to the state being in effect but not as central to
                         the state as a participant in a pivot role. The theme of a state
                         or event exists independently of the state or event.


selection is presented in Table 5. Using these roles, we determined common parts of the clusters’
members. They are presented in Table 6.

Table 5
Definition on roles based on our needs
   Role    Description                                                            Example
  Agent    Participant who initiates the action.                                  Crew
 EndLoc    Final state in which the patient of the action (e.g. a tool) is set.   Full thrust
  Goal     Participant that is the recipient of the message communicated          Passengers
           by the action.
 Patient   Participant that undergoes a change of state due to the action.        Thrust levers
 Source    Entity from which an information is fetched.                           Speed sensor
 Theme     Message content transmitted in a communication.                        “Prepare for landing”, “Take-Off”



3.2. Ontology
The PSL ontology was extended by introducing subclasses of Primitive. Each of those subclasses
appears in axioms characterising their common pattern exposed in Table 6. This ontology was
implemented in OWL.
Table 6
Classes and their roles
                          Class       Participant 1    Participant 2     Participant 3
                        Act               Agent          Patient              —
                       Fetch              Agent          Source             Theme
                    Communicate           Agent           Goal              Theme
                        Set               Agent          EndLoc             Patient


3.2.1. Extending the Ontology
Each class representing elementary instructions is a subclass of Primitive. The hierarchy is
described in Figure 4-a. Each instruction written in the FCOM is an instance of a class. Semantic
roles were added in the ontology using properties (in OWL sense), under the format hasXXX
where XXX is a semantic role. All the properties, except for hasEndloc, are object properties and
have an inverse property, called isXXXOf. The hasEndLoc property is a data property, whose
values are either literals or strings. This is due to the fact that the EndLoc role handles tool
states. Subclasses were also added to the PSL class Object. They are the classes of the different
participants. The hierarchy is described in Figure 4-b. DisplayDevice is the class of tools that
display some value, such as a clock. Sensor is the class of tools that record values about the
airplane, such as an altimeter. Trigger is the class of tools that agents can manipulate, such as
levers or buttons. With these roles and classes, we can represent the instruction “PF must set the
thrust to 25%.” as an instance of the Set class. Its formalisation in DL is represented as follows:

             Set(instr)            Person(pf)                          Lever(thrust_lever)
             hasAgent(instr, pf)   hasPatient(instr, thrust_lever)     hasEndloc(instr, “25%”)

   Each class of instructions has several axioms about which roles its instances should have.
These axioms are based on Table 6, which presents the pattern of roles corresponding to each
class of instructions. Note that each instruction particular is in relation with only one participant
playing this role. For example, the class Set is characterised by DL axioms 1, 2 and 3.

Axiom 1 (Each Set has exactly one agent). Set ⊑ =1hasAgent.⊤

Axiom 2 (Each Set has exactly one patient). Set ⊑ =1hasPatient.⊤

Axiom 3 (Each Set has exactly one endloc). Set ⊑ =1hasEndloc.⊤

   A new relation isComposedOf, and its inverse belongsToGroup (defined by definition 1), are
added to represent how groups are composed by their members. Axioms 4 and 5 define the range
of the properties.

Axiom 4 (Domain of isComposedOf ). ∃isComposedOf.⊤ ⊑ PersonGroup

Axiom 5 (Range of isComposedOf ). ⊤ ⊑ ∀isComposedOf.Person

Definition 1 (Definition of belongsToGroup). belongsToGroup ≡ isComposedO f −
      Primitive                                             Object
            Act                                                   Tool
                 Click
                 Decrease                                                 DisplayDevice
                 Increase                                                 Sensor
                 Push
                                                                          Trigger
            Fetch
                 Check                                                        Button
                 Monitor                                                      Switch
            Communicate
                                                                              Lever
                 Alert
                 Announce                                         PersonGroup
                 Notify                                           Person
            Set
                                                                  Message


Figure 4: Primitive class hierarchy (a) and Object class hierarchy (b).


3.2.2. Evaluating the Ontology
The ontology was implemented using Protégé, which helps check the consistency of the ontology.
Two procedures from the FCOM, each containing twenty or so instructions, were described and
the expressivity of the ontology was tested using SPARQL requests. The SPARQL requests were
based on competency questions, such as “Who has to do this action?” or “In which state this tool
must be set?”.


4. Discussion
4.1. Reduce Instructions Ambiguity for a Virtual Assistant
The ambiguity of instructions at meaning extraction is partially due to the lack of preciseness of
the XML schema used. This problem is visible with the Challenge-Response pairs. The type of
entity the challenge part should contain is not clearly determined. For example, Set instructions
can contain either the name of an entity playing an EndLoc role or a Patient role. In some rare
cases, one of the role players is in the Response. It is also important to note that sometimes, one
of the role players can be mentioned in the comment, or not at all. Indeed, the executions of
some of those instructions rely on the background knowledge of the pilots. This kind of implicit
knowledge hinders automatic extraction of the procedures. Defining a clearer framework to write
the FCOMs could be a consequent enhancement to achieve automatic extraction. The present
work can help to define this framework.
4.2. Tools States Representation
We represented tool states by strings. However, this method is not ambiguity-free. As we already
saw, there may be typographic variations between strings. A more general method would be
to have an ontology of tools, including sensors, of a plane. This ontology could describe in
particular the possible states these tools can be set on.

4.3. Shallow and Deep Roles Representation
Even if the current framework admits various roles, the difference between them is not necessarly
clear. The current axiomatisation is shallow and does not differenciate roles other than using their
domain and range. For instance, nothing differenciates the roles agent and patient. A deeper and
more complex axiomatisation is needed to have a better grasp of those differences.

4.4. Aligning the Ontology with an Upper Ontology
The change of interpretation of the PSL activities may impede the reuse of the PSL top-level in
the current taxonomy. Indeed, in PSL, Activity and Object were disjoint classes, as the former is
a class of universals of perdurants whereas the latter is a class of endurant particulars. However,
by classifying activities as informational entities, they arguably are endurants. Therefore the
top-level of the taxonomy should be re-examined. This could be done in the light of other upper
ontologies, such as BFO [12], DOLCE [13], GFO [14] or UFO [15].


5. Conclusion
This work led to the definition of a framework able to describe roles in procedures, and compatible
with the PSL ontology. This framework is a part of a bigger framework developed for a virtual
assistant capable of seconding a human agent in the execution of flight procedures.
   The presented work allows the description of instructions, i.e. utterances describing actions
involving various participants which can be clearly labelled. A taxonomy of the identified actions
is also given. Another benefit of this work is the identification of some lack of expressivity in
the FCOMs, leading to ambiguity in the instructions and a more complex extraction process.
The method described in this paper was only applied to FCOMs. However, it is usable for other
procedures manuals (e.g. cookbooks or medical and surgery procedures). This could lead to the
need for new roles.
   This work can be continued in multiple ways. Concerning atomic instructions, a better
framework to handle meta-instructions is needed. Working on the representation of physical
contexts in which the actions are realised could be of great help. This can serve to better constrain
the hasEndLoc property, for example.
   Finally, to enhance this framework, extended studies of other corpuses, such as clinical
procedures or cooking recipes, could help to generalize the ontology. The method presented is
not dependent of the FCOM and could be applied on other documents.
Acknowledgments
This work was carried out as part of a second year master internship funded by Airbus - Service
Engineering Computing & Communication Info & Data Processing.


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