|
On the other hand, not all examination papers contain practical
examples of real problems.
Some of my examination questions contain nothing but childhood fantasy.
Here is an example:
|
Question
1
The users advise us about the scenario of putting an elephant into the refrigerator as follows:
|
Open the refrigerator door.
If there is already a giraffe in the refrigerator, remove it.
Put the elephant into the refrigerator.
Then close the door.
On Children's Day on the 4th of April every year,
all the animals must attend the lion's party.
Open the door of the refrigerator automatically so that the elephant may attend the party.
|
|
Discuss any problems in the analysis use case diagram below ...
|
|
|
MY EXAMINATION PAPERS CAN REFLECT ADULT FANTACY
|
|
Some of my examination questions contain nothing but adult fantasy.
Here is an example:
|
Question
2
The latest car used by James Bond is a BMW Roadster with back-seat driving.
...
A remote control looks
like the standard control used in ordinary CD controls.
...
If the On/Off
button is pressed, a signal is sent from the remote control to the car.
When the car receives this signal, it will test whether weight of the driver
agrees with that of Bond.
...
If the weight of the driver is not the same
as Bond's, then back-seat driving will be activated.
...
When the Eject
button is pressed, the back seat is ejected.
(The air bag attached to the
back seat will be inflated in the shape of a parachute to allow Bond to
land safely.)
Draw state machine(s) ...
|
|
|
In spite of the fantacy, I am pleased to report that the external
examiner still commended us on the question.
I note also that the real James Bond owns a BMW 750iL with back-seat
driving subsequent to this examination paper.
|
MY EXAMINATION PAPERS CAN HAVE SERIOUS MISTAKES
|
|
Overwhelmed by the external examiners' positive comments on the
James Bond question above, I showed it to my young son after the examination.
My son pointed out a very serious mistake in the question, which was
overlooked by me the internal examiner, the three internal reviewers
and the external examiner.
Can you guess what it is?
There is no back seat in a BMW Roadster!
|
|
MY EXAMINATION PAPERS CAN HAVE WRONG PREDICTIONS
|
|
According to my examination paper in December 2003:
|
|
|
Question
3
Christian University (CU) and University of Spiritual Theology
(UST) will be merged together into one institute on 1 September 2004 ...
|
|
|
|
It was publically announced on 2 January 2004, however, that
the two universities will
not
be merged together.
Instead, CU, UST and Holy Kingdom University (HKU) will have a
"deep collaboration" with one another.
|
|
MY EXAMINATION PAPERS CAN BE SCARY
|
|
According to a forthcoming examination paper:
|
|
|
Question
4
According to legend, there are numerous ghosts hidden inside
the haunted house.
In order to see them, each visitor must put on a special pair of
spectacles before entering the house. ...
In this way, every visitor will be scared.
To avoid accidental heart attacks, ...
Unfortunately, ...
|
|
|
MY EXAMINATION PAPERS CAN REFLECT STUDENT CONCERN
|
|
My examination questions in software engineering may reflect
concerns expressed by students.
Here is an example:
|
Question
5
It is well known that most commonly used software engineering
methodologies are not supported by any formal foundation.
As a result, there is no theoretical framework enabling us to verify
the correctness of implementation.
On the other hand, when I teach formal methods to students, I receive
the following type of feedback:
|
From:
To:
The OBJ assignment is really so difficult.
I can tell you that OBJ is
the most difficult language in the world.
I really feel depressed and
helpless in the past two weeks when dealing with the assignment.
...
I really don't know what to do instead of just ignoring the assignment.
...
|
|
Discuss how attempts have been made to solve this problem by
integrating formal and practical methods.
|
|
|
During the examination, a few students actually laughed
(with agreement?) when reading this question.
|
|
MY EXAMINATION PAPERS CAN REFLECT SOCIAL CONCERN
|
|
My examination questions in software engineering may also reflect
social concern.
Here is a sample examination question during the SARS epidemic:
|
Question
6
There are two reasons why lifts are likely to transmit the SARS virus:
-
Lift buttons may be contaminated.
-
Lifts may be overcrowded.
The Medical Council proposes the following system to avoid these
problems.
Model the proposal using state machine(s).
-
There will be no button in lift lobbies or inside lifts.
-
On arriving at the lift lobby, passengers key in "168" to their
mobile telephone.
-
The telephone displays "please wait" on the screen, and sends a
signal to the lift controller, which includes a lift request and
the mobile telephone number.
-
The lift controller sends a signal to the mobile phone asking for
the floor number to go to.
-
The mobile phone displays "please enter floor number".
-
The passenger keys in the floor number followed by "#".
-
On receiving each digit, the telephone displays it on the screen,
and sends a signal to the lift controller, which includes that
digit and the mobile telephone number.
The treatment for the "#" key is similar.
-
After the "#" signal has been received, the lift controller
regards the entered floor number as complete.
Sometimes, however, a passenger may forget to enter "#".
If the lift controller does not receive any more digit for one
second, it will also regard the entered floor number as
complete.
For example, both "12#" and "12" followed by one second without
signal will be regarded as the 12th floor.
-
A floor number "0" is treated as the ground floor.
A "#" signal without any floor number is also treated as the
ground floor.
No signal at all for one second will similarly be treated as the
ground floor.
-
The lift controller then sends a signal to the mobile phone
asking the number of people travelling together.
-
The mobile phone displays a message "please enter number of
passengers".
-
The passenger keys in the number of passengers followed by "#",
or the number of passengers followed by one second without
signal, in a way similar to (g) and (h) above.
-
If the number of passengers is "0", it is treated as a
cancellation of request.
A "#" signal without any number is also treated as a
cancellation.
No signal at all for one second will similarly be treated as a
cancellation.
-
The lift controller selects a lift with sufficient room for the
specified number of passengers, and sends the lift number to the
mobile telephone.
-
The mobile telephone displays the lift number on the screen.
In this way, passengers do not touch any lift button.
Passengers will not squeeze into an overcrowded lift because the
capacity is carefully controlled.
The SARS transmission problem is therefore reduced, and people live
happily ever after.
|
|
|
|
|
|