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Process Enactment
L18
Topics
• Faculty processes
• Modelling the process
• Enactable process models
• An example process-based system
• Issues in Process modification
• Issues in system acceptance
Faculty Processes
• Staff are involved in many ‘long-running’ processes:– Coursework preparation and moderator– Examination preparation and moderation
• Students are too:– Computing project: from briefing, inception, tutor
meetings, poster session, submission, possible late work, double marking by supervisor and second marker, referral to project module leader in case of dispute, agreed marks to admin, Field board approval or adjustment.
Coursework setting:An idealised Scenario
• Ian is the module leader for a number of modules, including Information Design, a MScIT module. On his own page on the CEMS portal is a list of the modules he leads, the modules he teaches on as a tutor and the modules for which he has other responsibilities, such as mentoring the module leader or internal moderation. Information Design has small list of pending tasks. One coursework is coloured red -, an indication of the priority derived from comparison of today’s date with the hand-in date – required period of student work minus estimated time for setting and moderation (an estimate which currently is the same for all staff, but over time will alter to reflect actual time taken)…..
Exam moderation process
• Current process is mostly defined by the moderation sheet, initiated by the module leader, completed by the moderator
• Problems– Leader: What is the exam length? Who is the moderator, whats
her email address, what’s the code? Are there any standards to follow?
– Moderator: What papers am I moderating? When can I expect them? Is the ball in my court or the module leaders? Where is the module specification?
– Field Leader: Whats the state of play across the board? What papers are being disputed?
– Programme Administrator: when can I send the papers to the external examiner?
Design principles
• Provide a single point for information about the moderation process– Guidance in the process – Relevant documents
• Make the process specific– People associated with their roles– Pre-completed forms– Current state of process– Allowable future actions – whos got the ball?
• Make the process visible– To field leader, programme assistant
Design issues
• How far should the information system participate?– Just advising on possible actions– Logging actions– Holding exam moderation comments and responsed– Holding the exam paper and solutions
• Access control– Who can see the state of a process - only the actors,
actors + manager, all staff in the field, everyone– Who can initiate actions – only the agent?
Process Models
• Use case
• Entity Life History
• Sequence Diagram
• UML State chart
Use Case Diagram
Set and moderate exam paper
Module leaderInternal moderator
Field leader
Programme Assistant
ELH
Request paper
Set paper
Sent for review
approve Send to admin
Request changes
review
Modify Send back for review
*
Paper life
Field leader Module leader Internal moderator Programme assistant
Set paper
review
modify
review
request
paper
changes
Revised paper
approve
Approved paper
Statechart
Boxes are states
Ellipses are transitions between states
Enactable Processes
• Processes are long-running, so can just write a program since programs are restarted when loaded.
• Important to distinguish between – ‘process class’ – the general case – the ‘schema’ – a description
• E.g. the CEMS exam moderation process 2004
– ‘process instance’ – a specific, running process, in a specific state at a given time
• E.g. setting and moderating the ISD3 exam paper according to the CEMS exam moderation process 2004
• XML-based descriptions are emerging • State-based models are easier to implement
Process
Role State
Transitionagent
from
to
Processinstance
event
timestamp
Current state
Process model in MySQL• create table processes (• pid integer not null primary key,• name char(255)• );
• create table roles (• rid char(30) not null primary key,• name char(30)• );
• create table states (• pid integer not null references processes(pid),• sid integer not null,• sdesc char(255),• scolor char(12),• primary key (pid, sid)• );• create table transitions (• pid integer not null references processes(pid),• tid integer auto_increment not null,• fromsid integer not null,• tosid integer,• name char(30),• agent char(30) references role(rid),• tdesc char(255),• primary key (pid, tid),• foreign key (pid, fromsid) references states(pid, sid),• foreign key (pid, tosid) references states(pid, sid)• );
Creating the exam moderation process• insert into processes values (100, 'Exam moderation process');
• insert into roles values ('internal', 'Internal Moderator');• insert into roles values ('external', 'External Examiner');• insert into roles values ('mleader', 'Module Leader');• insert into roles values ('fleader', 'Field Leader');• insert into roles values ('pa', 'Programme Assistant');
• insert into states values(100,0,'To be requested','red');• insert into states values(100,1,'Paper Requested','red');• insert into states values(100,2,'Paper Set','red');• insert into states values(100,3,'With Internal Moderator 1','orange');• insert into states values(100,4,'With Internal Moderator 2','orange');• insert into states values(100,5,'Module leader revising','orange');• insert into states values(100,6,'With Internal Moderator 3','orange');• insert into states values(100,7,'Approved', 'lightgreen');• insert into states values(100,8,'Sent to admin','green');• insert into states values(100,9,'Received','green');
• insert into transitions values(100,null,0,1,'Requested','fleader','requests %mleader to set paper.');• insert into transitions values(100,null,1,2,'Set','mleader',
'sets the examination paper, solutions and marking scheme.');• insert into transitions values(100,null,2,3,'Sent to Internal Moderator','mleader',• 'sends the examination paper to the %internal with the moderation form.');• insert into transitions values(100,null,3,4,'Reviewed','internal',• ' reviews the examination, recording brief comments on the form and more extensive ones on the question paper
or solutions. '); • insert into transitions values(100,null,4,5,'Changes requested', 'internal', • ' either returns the review to %mleader for changes');• insert into transitions values(100,null,4,7,'Approved','internal',• ' or approves the paper.');• insert into transitions values(100,null,5,6,'Modified','mleader',• 'modifies or defends the paper and returns to %internal');• insert into transitions values(100,null,6,4,'Changes reviewed','internal', • ' reviews the changes made and /or the defence.');• insert into transitions values(100,null,7,8,'Sent to Admin','mleader',• 'sends the paper to the %pa when finally agreed.');• insert into transitions values(100,null,8,9,'Received','pa','Receives the completed paper and solutions.');
Examinations are Process instances
• create table examinations(• eid integer not null primary key,• mcode char(20) references modules (mcode),• length int,• dateheld date,• pid integer,• sid integer,• foreign key (pid,sid) references states (pid,sid)• );
• create table events (• evdate timestamp,• eid integer not null,• pid integer not null,• tid integer not null,• );
• insert into examinations values (1,'IFI8KE-15-M', 180, '04/5/1', 100, 0);• insert into examinations values (2,'IFIE8U-20-2', 120, '04/5/1', 100, 0);
Also need a Faculty Model
Field
Module staff
examination
Field leader
Programmeassistant
leader
moderator
processmodel
external
Faculty model• create table ffields (• fcode char(8) primary key,• name char(30),• leader char(8) references staff(username),• pa char(8) references staff(username)• );
• create table modules(• mcode char(20) not null primary key,• fcode char(8) references ffields(fcode),• title char(80),• leader char(8) references staff(username),• internal char(8) references staff(username),• external char(8) references staff(username)• );
• create table staff (• username char(8) not null primary key,• fullname char(30),• email char(40),• ext char(6),• homephone char(20)• );
• insert into staff values ('iabeeson', 'Ian Beeson', '[email protected]',83156, '0117 555555');• insert into staff values ('cjwallac', 'Chris Wallace', '[email protected]',83156, '0117 888885');• insert into staff values ('amoggrid', 'Anne Moggridge', '[email protected]',83333, '0117 66666');• insert into staff values ('twakefie','Tony Wakefield','[email protected]',86666, '0117 54344');• insert into staff values ('kcurtis', 'Kate Curtis', '[email protected]',83254,null);• insert into staff values ('sp','Steve Probert','[email protected]',null, '0207 77777');
• insert into ffields values ('IS', 'Information Systems', 'amoggrid', 'kcurtis');
• insert into modules values ('IFI8KE-15-M', 'IS', 'Information Design', 'iabeeson','cjwallac','sp');• insert into modules values ('IFIE8U-20-2', 'IS', 'Information Systems Development 2', 'twakefie','cjwallac','sp');
Process Architecture
HTML + CSSPresentation layer:
Data layer: MySQL
Business Layer: PHP, GraphViz
Interaction Architecture
Index.html
Showmod.php
Showexam.php
eid
Showform.php Module spec Showprocess.php
eid eid
(update) eid, sid, tid
Showstatechart.php
Showexam.php pseudo code
• If required, update the state of the exam process and log the event.
• Get the exam, module and field• Get the roles• Associate staff with roles• Get the list of events and store the last time stamp• Read through the transitions for this process:
– Adding in the timestamp if transition has already occurred– Adding button to execute the transition if its fromstate = current
state (i.e. it’s a possible transition)• List all the roles and the staff• List links to useful resources – the moderation cover
sheet, specification …
Extensions to the basic Process (1)
• Actions on transitions– In the current demo, executing a transition just
changes state, and logs event.– In general, we want to add an action to the transition
• e.g. send an email to a role to notify them of required role • can add this to the process model (in what language?)
• Timed transitions– If the paper is not set by a given date, an alert is sent
to the field leader and the module leader:• Transition defines a date• Background process run every night would enact transitions
for process instances waiting on a timed event.
Extensions to the basic Process (2)• Compound processes
– Our model is ‘flat’ – no composition– Sub-processes will be common to several processes (‘uses’
relation in use cases)
• Inheritance– The process of exam moderation and coursework moderation
are very similar – there may be a common superclass which defines a common structure, of which exam and coursework are sub classes
• Concurrent processes– In the bank loan process, each loan request proceeds as a
separate process, and merge when both are done
• Process to process communication – What if an action in one process caused a transition in another – e.g. the field leader has a process in which papers are batched
for sending to the external – in batches of 10 – Completion of moderation causes batch to increment
Extensions to the basic Process (3)
• Schema modification– Suppose we need to modify the process class when
we discover some additional behaviour:• If the leader and the moderator cant agree, the problem is
referred to the field leader, who either approves or sends the paper for revision, which must be agreed with the field leader before sending to the programme assistant
– How do we change the process – can we just update the process model?
– Problem with existing process instances – these are in states defined by the old process model, which may not be or may be different in the new model
• This a critical problem with long-running processes.
System acceptance
• What functions are missing from the system?
• Can we anticipate how well this system will fit– In the context of the Information Systems
school? – With different stakeholders?
• How could we measure fitness?
