Transcript 平成18年度研究件名 - Metadata Standards

Comments on
WG2_N1421_5th_SP_of_CD2_19763-5
OKABE, Masao
Expert Contribution
2010.11.17
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1. Relation between Part5 Process model and Part7 Service model
2. How can the process models created with a specific modeling
language be registered in MFI Part5 ?
3. What should be the common semantics ( or essential subset) of
process models ?
Note
 Unfortunately, all the comments are
on WG2_N1421_5th_SP_of_CD2_19763-5,
and not on WG2_N1467_ 6th_SP_of_CD2_19763-5.
 But I guess most of the comments, and I believe at least some, can
be also applicable to WG2_N1467_ 6th_SP_of_CD2_19763-5.
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Issues that need be discussed on MFI-Part5
1. Relation between Part5 Process model and Part7 Service
model
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Relation between Part5 Process model and Part7 Service model
Process
4.1.1 Process at WG2_N1421_5th_SP_of_CD2_19763-5
 a set of activities and resources, organized by a dependency construct,
which all participate in fulfilling a given purpose.
SE VOCAB definition 7--- our preferred definition at Wuhan project
meeting in August
 system of activities, which use resources to transform inputs into outputs
(ISO/IEC 25000:2005 Guide to SQuaRE, 4.41)
Service
4.2.1 Service at WG2-N1201-WD_19763-7
 a kind of Web based application, which encapsulates certain computing
module and can be accessed by certain interface.
A question is whether a service is a kind of process or not?
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Original understanding of a process and a service
My original understanding of a process and a service is that
a process intends to represent capability (see WG2N1441aMFI 5 Proposed Standard Terms) or common semantics of a
service, independent of its implementation,
based on;
This part of ISO/IEC 19763 specifies the metamodel that provides
a facility to register administrative structural information
and meaningful semantics of process models, including
workflows, business processes, Web services, etc.
 at 1 Scope of 32N1819-text_for_ballot-CD_19763-5.pdf
The relationship between MFI PMR and MFI Service means that
a process can be realized by zero to many instances of Service
and a service can achieve only one Process.
 at 5.2 Relationship between MFI PMR and some parts in MFI
of 20100131 3rd_SP_19763-5.doc
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Original understanding of a process and a service
achieves
Process A
realized by
Service B
Service C
Service D
Service E
in SOP
in REST
in JAVA
in Rails
・・・
All of the services B, C, D, E have the same capability.
Since a service has only one capability(totally), ideally,
the multiplicities between Process and Service are as follows;
Unfortunately, this is almost impossible
because in MFI Part5 registry it is almost
impossible to ensure that one fact (capability)
is one place is almost impossible.
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Process
0..1
0..*
Service
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Changes from CD1
In WG2_N1421_5th_SP_of_CD2_19763-5.doc
“only one” was relaxed to “zero to many” at
“The relationship between MFI PMR and MFI Service means that a
process can be realized by zero to many instances of Service and a
service can also achieve zero to many Process.”
 at 5.2 Relationship between MFI PMR and other parts in MFI
of 20100131 3rd_SP_19763-5.doc
References hasPrecondition: Precondition[0..*]” and
hasPostcondition: Postcondition[0..*]“ of Process,
which exist in 20100131 3rd_SP_19763-5.doc,
are removed.
although, at Introduction, there still exists a sentence
“On the other hand, a process expresses the semantics
of a service to support semantic discovery of a service.”
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OKABE, Masao
Process
0..*
0..*
Service
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About Changes from CD1
 Now, I am confused on these changes;
1. In what senseis the multiplicity constraint is relaxed and
What many-to-many relations between processes and services mean?
 For example,
 in the case that a process can be realized by three instances of Service, this
means each instance can realize the process or all the three instances as a
whole can realize the process?
 in the case that a service can also achieve three instances of Process, it
means that this service achieves the three different Processes, or this service
achieves one of the three processes and the other two Processes must be
equivalent to the one?
2. How MFI Part5 represent semantics of a process without pre- and postconditins?
 What is the common semantics of processes which are necessary from the
point of RGPS?
 Do we really need a process (model) which dose not have a precondition nor
postcondition?
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2. How can the process models created with a specific
modeling language be registered in MFI Part5 ?
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MFI Part5 Process Model Example
Let us think about this very simple process model on the left,
A
yes
no
B
C
MFI Part 5 models this as follows;
process
conditional process A
event: yes
dependency
construct
process A
process
conditional process B&C
process B & C
event: no
process B
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process C
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MFI Part5 Process Model Example
It is unnecessarily complex and confusing.
A simpler and easy-to-understand model is desired.
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Table C.2 – Mapping table of Process_ Modeling_ Languages
If we look at Table C.2 – Mapping table of Process_
Modeling_Languages at Annex C of WG2_N1421_
5th_SP_of_CD2_19763-5, there are many problems to
register process models created with the languages.
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Treatment of Initial and Final
All of BPMN, UML activity diagram and UML state machine
have a initial and a final event (or node or state).
All of them have almost the same semantics.
But, MFI Part5 treats them differently.
In BPMN, they are mapped to Events, if we look at Table
C.2.
In UML activity diagram, they are ignored if we look at
Figure A.2.1.
In UML state machine, they are mapped to the attribute of
resource , if we look at Table C.2.
They should be treated uniformly in MFI Part5.
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About BPMN at Table C.2
In some cases, an Event of BPMN has to be mapped to a
Process of MFI Part5, instead of a Process of MFI Part5.
See an example below.
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Example from Business Process Model and Notation
(BPMN) Version 1.2 formal/2009-01-03
Let us focus on gateway “Conference Call in Discussion
Week?” and event “wait until Thursday,9 am”.
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Example from Business Process Model and Notation
(BPMN) Version 1.2 formal/2009-01-03
If we see Figure A.2.3 of an example of UML activity
diagram at WG2_N1421_ 5th_SP_of_CD2_19763-5,
Gateway “Conference Call in Discussion Week?” should be
mapped to a XOR_Split_Process and a
XOR_Split_Construct, which creates a conditional process
as a node set, which has event “Yes” as a guard condition
and has a process as a resultProcess.
But, in this case, this result process is not a a process but
an event, because event “wait until Thursday,9 am” is not a
process but an event.
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About IDEF0 at Table C.2
(1 of 2)
In IDEF0, a arrow has roles of Input, Output, Control,
Mechanism and Call.
Except a Call arrow, it does not necessarily a
Depebdency_Construct, which designates the order in
which processes (Boxes) are executed.
For example,
A Forking Arrow (from Output to Input) only represents that
Output of a Box becomes Inputs of different Boxes.
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About IDEF0 at Table C.2
(2 of 2)
Input and Output are roles of an arrow and are not
resources or objects themselves.
For example, in the case, Box A outputs some chemical,
which is an input of Box B, there are two roles, one is
chemical as an output and the other is chemical as input.
But, there is only one resource as chemical.
Input and Output of IDEF0 should be mapped to attribute:
consumes and creates of Process in MFI Part5,respectively
Control, Mechanism and Call may be mapped to attribute:
refersTo of Process in MFI Part5.
An important elements of IDEF0 cannot be mapped to MFI
Part5.
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About IDEF3 at Table C.2
In IDEF3, an object can have many states which translate
from one to others.
But, a Recourse in MFI Part5 can have at most one status.
An important element of IDEF3 cannot be mapped to MFI
Part5.
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About UML Activity Diagram at Table C.2
From UML 1.x to UML 2.x, Activity Diagram was changed
fundamentally in some sense.
That is, an activity in UML 1.x is an activity state and a kind of state, but
an activity in UML 2.x is not a kind of state.
But, practically, they are similar.
If we look at Table C.2, an activity (of UML 2.x) is mapped to a Process.
But an activity in UML 1.x is mapped to an Attribute of Resource:state
since it is a state.
This is not good.
So, MFI Part5 should map a state in UML state machine to a Process,
like UML 1.x.
And, MFI Part5 need to introduce a mechanism to handle an object (or
a resource) uniformly.
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About UML State Diagram at Table C.2
It should be UML State Machine.
There is no state diagram in UML. It is a state machine diagram.
State machine at least in UML 2.3 (current version) does not have any
of Action. Object, Event, Condition.
Where do they come from?
Bibliography refers to Martin Fowler, UML Distilled: A Brief Guide to the
Standard Object Modeling Language, Third Edition, 0-321-19368-7
 This is just a famous text book. MFI Part5 is based on the official UML
documents.
Table refers to ISO/IEC 19501 Information technology – Open Distributed
Processing – Unified Modeling Language (UML) Version 1.4.2.
Should MFI Part5 should uniformly refers to ISO/IEC DPAS 19505-2
Information technology -- OMG Unified Modeling Language (OMG UML)
Version 2.1.2 -- Part 2: Superstructure ?
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About PSL at Table C.2
(1 of 3)
In PSL, type (or class) and occurrence (or instance,
individual) are strictly distinguished.
For example, an Activity is (an instance of ) a type, and an
Activity occurrence is (an instance of ) an occurrence.
MFI Part5 does handles no occurrence (or instance,
individual) .
So, Activity occurrence in PSL should not be mapped to
Process in MFI Part5 and should be ignored in MFI Part5.
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About PSL at Table C.2
(2 of 3)
An object in PSL is almost anything in UoD, except an
activity or an activity occurrence.
This is not necessarily a resource in MFI Part5.
In MFI Part5, a resource is only a resource participating in a
process.
What is a meaning of “participating in a process”?
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About PSL at Table C.2
(3 of 3)
PSL Part13 has Subactivity occurrence ordering core
Theory.
This should be mapped to Dependency_Construct.
They need to be mapped properly to
Dependency_Constructs in MFI Part5.
Strictly speaking, they are not about Activities but Activity
occurrences, while Dependency_Constructs are about Activities.
But, when mapped to MFI Part5, this difference may be ignored.
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About UML Interaction (Sequence Diagram)
Could you add UML Interaction to Table C.2 and provide an
example?
Because to represent interactions (concurrency) of
processes is an important issue and a Sequence Diagram
can provide a simple and godd example.
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3. What should be the common semantics ( or essential
subset) of process models ?
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Clear Scope and Objectives are necessary
To resolve these problems and chose a common semantics
of process modeles, we need an agreement of the position
of MFI Part5 in RGPS and also in MFI family.
WG2_N1436_Scope_of_19763-5 says
Now we are thinking……
MFI‐5 is for RGPS
 Process is one kind of service‐related model
MFI‐5 should provide semantics of services,
rather than a general metamodel for various
process models
 Support semantic discover of a service
 Help orchestration of Web services
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Clear Scope and Objectives are necessary
The statement above “rather than a general metamodel for
various process models” is inconsistent with MFI basic
policy (or structure).
We do not need to develop new RM-ODP or IE.
In spite of the statement above “MFI‐5 should provide
semantics of services”, MFI Part5 seems drifting
from “representing semantics of services”
to “representing flow of processes”,
since Pre- and Post-conditions are removed.
What is it (Now we are now thinking……) now?
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Basic Structure of MFI
<MFI>
Part10 Core model
(and basic mapping)
Part3 Ontology
registration registry
entries of
ontology
A
MFI presupposes the existence of complete
repositories of models outside MFI.
All the parts (except Part1 and 6) inherit Part10.
Part10 is not necessarily abstract (meta)classes.
Part8 Role &Goal
registry
Part5 Process
model registry
entries of
ontology
B
・・・
entries of
process
model C
entries of
process
model E
entries of
process
model D ・・・
・・・
entries of
process
model D ・・・
Only common semantics (essential subsets) are registered in MFI registry with some additional information.
<Outside MFI>
ontology
A
OWL
ontology
repository
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ontology
B
・・・
Common Logic
ontology
repository
process
model D
process
model C
RM-ODP
process model
repository
・・・
PSL
process model
repository
OKABE, Masao
Role &
Goal E
KAOS
role & goal
repository
Role &
Goal F
・・・
i*
role & goal
repository
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Other comments 1
If we look at slide 21 nad 22 of WG2_N1433_RMODPRGPS_Registration_Example at Kunming, most of MFI
Part5 processes are human processes except “Validate
loan:Loan validation”.
But, if I remember correctly, at Kunming meeting, we
tentatively agreed that MFI Part5 only targets on
“computerized” processes.
So, what should they now?
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Other comments 2
From the point of RGPS, a more scenario-based approach
is necessary.
For example, who creates (or are responsible for creating)
links between Processes in Part5 and Services in Part7?
If this is out of the scope of MFI Part5 and Part 7 (that is,
some one can do that somehow), it is better that Part5 has
pre- and post- conditions in accordance with the principle
that one (unfortunately in this case, almost imposiible) fact
(capability) is one place.
If to support this (creating links between Processes and
Services) is within the scope of MFI Part5 and Part7, both
Part5 and Part7 need to have pre- and post- conditions.
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Other comments 3
I guess that the devision of MFI Part5 and Part7 are based
on OWL-S, which I do not know whether is appropriate or
not.
It would be a good idea to model “BravoAir reservation
service example” using both MFI Part5 and Part7.
“BravoAir reservation service” is an OWL-S example.
MFI Part5 already provides it but MFI Part7 does not yet(?).
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Other comments 4
I do not have any objection to forwarded WG2_N1467_
6th_SP_of_CD2_19763-5 to CD2 ballot.
In that case, most of (at least, some of) the comments here
will be Japanese comments and be discussed at BRM of
CD2.
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