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Bookshops
After church, Li-Xia and I
went into the city. We parked our bikes outside of
bookshop "De Slegte", but first went into bookshop Broekhuizen because "De Slegte" was
still closed. On the third floor we watched the
exhibition De dinsdagschilders van
Mia van
Jeveren (The Tuesday painters of Mia van
Jeveren). When it was after one o'clock, we
went back to bookshop
"De Slegte". First we went to the second floor
where I looked at the encyclopedia again, and made my final decision
not to buy it. When I was standing before the newly
acquired second hand books, Li-Xia noticed a Chinese
dictionary. (I had shown it to her yesterday, but appearently she had totally forgotten
about it, as happens more often.) It is a childrens
dictionary with a little drawing besides each word
explaining the meaning. The title of the dictionary is Tu wen shuang jie xiao xue sheng zi ci dian
and the ISBN is 7-5385-1786-3. It costed € 15.
(In the evening, I discovered that on the back of the
book it states that it costed 32 Yuan, about one fifth
of the price.) She was sure she wanted to buy it.
I also decided to buy a book, the book
Strip: 1,5 kilometer woningbouw in Den Haag
(Strip: One Mile of Urban Housing in The Hague),
for € 4,25. (KMZ file
of the location of the strip.)
Plane crash
With respect to the Turkish Airlines Boeing 737-800 crash
at Amsterdam last week, according to
this flightglobal.com article,
a press release from Boeing states:
Boeing will warn crews about fundamentals like flying
the aircraft, monitoring airspeed, monitoring altitude,
and will give advice about radar altimeter issues.
This almost sounds like:
General Motors (or any other car large manufacturer) will
warn drivers about fundamentals like driving a car,
monitoring speed, monitoring the road, and will
give advice about warning lights.
But of course, things are not as trivial as they sounds.
From the information I have heard, I guess that the following
sequence of events took place:
- As was the custom of the airline, the crew decided
to land with the auto-pilot and the autothrottle.
- At a height of 1750 feet, one of the radar altimeter
suddenly reported an incorrect value of minus 8 feet.
This signal was noticed by the pilots, but they
concluded it could be ignored, because the other
three altimeters were still working correctly.
But due to this the autothrottle went into "retard"
mode and the throttles then stayed at idle, causing
the airspeed getting lower and lower. One of the
reasons why the pilots did not notice this, was
that the aircraft was initially high and fast
on the approach, and it would be normal for the
engines to run (almost) idle in order to reduce
the speed as quickly as possible.
- About 100 seconds later, the stick shaker activated
because the aircraft was about 400 feet above ground
and getting dangerously low. The first officer, who
was having the controls, then probably realized that
airspeed was far to low and immediately increased power.
- However, it was a training flight for the first officer,
who although being a qualified pilot, had never flown
this type of plane. For this reason the captain
decided to take over the controls. Because of this
the throttle switched to idle again. The captain too
noticed that the aircraft was dangerously low, but
maybe did not realize that this was due to the low
airspeed. I decided to pull up the nose of the aircraft,
which in fact did only make things worse, because the
plane started to stall. Only then he realized what
was going on and increased power (6 seconds after it
went to idle). But sadly it was too late and the plan
fell to the ground.
As usual a chain of unexpected events was the result
of this crash. Both pilots (actually there where three
of them in the cockpit) made the wrong assumption about
what was going on. But looking at the behaviour of the
plane as a software engineer, I also notice some strange
things. First of all, I see a poor integration between
the various systems in the aircraft. I understand that
there is always a danger of a strong integration between
the systems in an aircraft, because a problem in one of
the systems could lead to an unexpected cascade of events
in all systems and led to a complete breakdown of the
system.
It looks like there where two separate systems for
controlling the plane, both of them having two altimeters,
one radar altimeter and one
pressure altimeter. The autothrottle maybe went into IDLE because the two
altimeters gave conflicting readings. Autothrottle is
almost always switched on during the flight. Appearantly
there was no clear signal that the autothrottle went into
"idle" mode. It is also strange that the auto-pilot,
responsible for controlling the height and the flight path
of the plane, was not switched off, because it is clear
that with an incorrect speed, the auto-pilot cannot
operate correctly. I am getting the impression that the
whole auto-pilot and autothrottle system was not tested
against all possible scenarios. I can understand that
the autothrottle was switched of because one of the altimeters
was giving an incorrect reading, but this makes it even
stranger why the auto-pilot, which also depends on the
altimeters was not switched off. It would not surprise
me if the auto-pilot and the autothrottle systems were
designed by separate design teams, and that due to this
the operations conditions where not exactly matched.
See also:
Autopilot and autothrottle
To me it seems that the design of the autopilot and
autothrottle system was even more flawed than I thought.
I now understand that there are to autopilots in the
plane and only a single autothrottle system. The
autothrottle depends on the left radar altimeter.
The two autopilots make use of their own radar altimeter.
The autopilots can either work together in dual channel
mode or one of the autopilots can be selected to fly the
aircraft. It seems that the aircraft was flying on the
right autopilot, which takes it height readings from
the right radar altimeter that was still operating
normal. This somehow explains why the autopilot was
not switched on while the autothrottle went in to
'retard' mode. Boeing strongly advices against flying
in this mode. (In this discussion it states that it is not even certified.)
The reason for it seems quite obvious now.
But I wonder if the designers did not feel that there was
something intrinsically flawed in the design of the
system? (If it not certified, it should not have been
possible without clear warning signs to the crew.)
But besides this discussion, this forum messages states: "The brutal truth of
the matter appears to be that no one was flying the
aircraft."
Freedom of speech
Today, the High Council (Supreme Court) of the Netherlands has ruled
(BF0655) that Article 173c cannot be interpreted in a broad sense such that
offending statements about a certain faith cannot be interpreted as
being offending to a group of the believers of this faith solemnly
on the fact that they feel offended by those statements.
It looks like that this is counteracting a court ruling on
January 21 which stated that
Geert Wilders should be prosecuted with
respect to his statements about Islam.
Playing Go
Yesterday, I found out that a new colleague can
play Go and that we are about the
same strength. Today, I brought my playing set with me,
and during the lunch break we played a game. All the other
colleagues, who where watching our game, where making
all kinds of remarks about what the game was about. Only
a few know the rules. I left my game set in the office,
because I think we will play more often. I hope that some
others get interested as well.
In the evening, I went to the university and found Rudi
and Taco deeply encaged in a game. I watched the game
and tried to understand what was going on, but as usuall
I found this quite difficult. It became clear to me that
at the level at which they are playing the game, completely
different considerations take place than at the level I
am playing the game. They also spend some time analyzing
the game and playing through various alternatives.
Week of the book
Once per year, there is a week of the book in the Netherlands.
This year it is from March 11 till 22. Every year there is
also a present, a small book, which you buy books for a certain
amount. Each year an aclaimed author is asked to write the gift
book. But not all bookshops join the organisation. One example is
De Slegte, because
they sell books that have been remaindered and second-hand
books. Today, the shop in Enschede
had many second-hand "week of the book gift" books for sale for
just one Euro. I bought the following four:
- De heilige Antonio by Arnon Grunberg. (1998)
- Het theater, de brief en de waarheid by Harry Mulisch. (2000)
- Gala by Ronald Giphart. (2003)
- De pianoman by Bernlef. (2008)
Playing Go
This evening, I went to the university to play Go.
When I arrived, I found Taco drinking some tea. We moved to a place
where we could play. I had brought my Chinese playing set, which
I received on July 27, 2006 as a gift
from Mrs. Guo, because my regular set is still in the office and
has an unfinished game sitting on it. Because Taco had brought a
wooden board, we decided to play with his set. I was given seven
stones ahead. I resigned when I lost a group in the corner. In the
mean time Huub had arrived as well, and we replayed the game, and
Taco showed me all my big mistakes. Sometimes, I wonder how long it
will take me to learn from my mistakes. At home I tried to reconstruct
the game record.
Possible link between Reminyl and epilepsy
The BBC-news article Protein 'behind Alzheimer's fits'
hints at a possible link between epilepsy (as seen with people
with Alzheimer's Disease)
and drugs like Reminyl, which Li-Xia is taking right now.
According to media release, Professor Tibor Harkany has discovered that beta-amyloid
is causing nerve cells in the brain to fire more
frequently, which could lead to epilepsy. Some
drugs, like Reminyl, could lower the seizure threshold
because they stimulate the signaling between nerve cells.
This evening around half past seven, while I was biking home,
I noticed a bright star in the sky, but when I saw that it was
moving, I concluded that it could not be a star. I realized I
might have accidently seen the International Space Station with
the Space Shuttle Discovery (on mission STS-119) attached to it, flying overhead. At
home I checked if it could be true, and found
this page affirming my observation.
This first time, I saw the International Space Station fly
overhead was on Sunday, June 18, 2006.
Going into the city
This afternoon, I went with Annabel
into the city. First when went to a clothes outlet shop to
look at some All Stars shoes. Next we biked into the city
and noticed someone biking before us with a big dog, and I suddenly
thought it was Christian Freeling.
I tried to take over and cried "hello", but it seems he did not
immediately recognize me. A little further, he turned around
and I told him who I was. Some months ago, I contacted him because
he created a link from one of his pages to my page about
Havannah, a game which he invented. We shaked hands and we
talked a little.
Annabel and I went into bookshop
De Slegte and looked around. I found the book Zoeken naar
de stier (a translation of The Search, talks on 'The Ten
Bulls', of Zen) by Bhagwan Sri Rajneesh. Annabel found some books by Carry Slee
Hot or Not, your choice and Pijnstillers. We decided
to buy all three books. I payed € 25.40 at 16:08:55.
Next we went to Dynabyte to
look for a small laptop (netbook) for Annabel to use in school.
We look at several models and concluded that the Samsung NC10
was our best choice. We went to three different shops, but did
not find another computer matching our requirements better. We
ran into Valeri Souchkov,
with whom I shared a room during working on the TransCoop project. Back at Dynabyte, we bought a
Samsung NC10 netbook.
Device capabilities
At my company we encountered some problems with certain
printers not showing gradient colours. At first we concluded
that there was a problem with some printer drivers not supporting
gradient colours. One such example of a printer driver is
PDFCreator,
a very handy printer driver for printing to PDF files.
Last Monday we discovered that PDFCreator was able to produce
gradient colours when printing from some other application.
Yesterday, at the end of the day, after I spend a long time
looking at EMF, I discovered that some routine in our software concluded
that the printer driver was a low (colour) resolution device.
It did so by retrieving the number of bits per pixel with
a call of GetDeviceCaps for BITSPIXEL. PDFCreator returns 1 for
this parameter, which gives the impression that is a black and white
printer.
When I studied GetDeviceCaps documentation, I found that there where is
a whole range of parameters related to colors. These are:
- BITSPIXEL: Number of adjacent color bits for each pixel.
- PLANES: Number of color planes.
- NUMCOLORS: Number of entries in the device's color table,
if the device has a color depth of no more than 8 bits per
pixel. For devices with greater color depths, 1 is returned.
- COLORRES: Actual color resolution of the device, in bits per
pixel. This index is valid only if the device driver sets the
RC_PALETTE bit in the RASTERCAPS index and is available only
if the driver is compatible with 16-bit Windows.
- COLORMGMTCAPS: Windows 2000/XP: Value that indicates
the color management capabilities of the device.
I really had to laugh when I saw this list, because it clearly
shows how the capabilities of output devices (printers and graphic
cards) evolved through the years, and how one method of specifying
the colour abilities has been replaced by another.
Today, I discovered that PDFCreator returns the flags CM_DEVICE_ICM
and CM_CMYK_COLOR for COLORMGMTCAPS, meaning that it does support
Integrated Color Management, which is clearly an indication
that it does support colours.
At noon, when I wanted to play some Go
with the colleague of mine, I discovered that another
colleague, who does not really know the rules, nor understood
the goal of the game, already had started playing. Nevertheless,
he did not play very bad. Of course he lost, but it was not
a complete defeat.
This evening, I went to the university. When I arrived, Rudi
and Taco had already started a game. I watched them until
Huub arrived and we started playing where he got two stones
ahead. Right at the beginning, he lost some stones. Somewhere
in the middle, I too made some stupid mistakes. When we
counted we both had 53 points. We replayed the first half
of the game. At home I reconstructed this game record.
Some hacking
This evening, I wanted to secure some data that still might
be on my computer ester.
For this reason, I brought it downstairs and connected the
keyboard, mouse and monitor now attached to my computer lixia. It started up as normal, but
I quickly discovered that I did not have a network connection
and that I could also not attach some USB-drives to it because
no drivers being available. Then I decided to simply take the
30 Gbyte Maxtor drive out of it. By accident, I first removed
the seagate ST51270A hard disk. I opened lixia and
put the Maxtor drive on the cables of the DVD drive, and when
I started, it booted from the Maxtor drive, starting with
Windows 95 and gave a message about a new device. I quickly
switched it off and changed the order of the boot-devices,
thereby noticing that the first boot-device was the card
reader. How wierd. When that worked, I attached the
Freecom USB drive to
lixia and copied all the data I might want to keep,
a total of 2,28 GByte in 25.398 files. When I was done, I
put everything back as before.
Sitting outside
It looks like spring has finally started. Today, it is the
first time that my colleagues went outside during lunch time,
with their coats on, that is. Last year it was February 11, at least six weeks earlier.
This evening, I finished reading
the Dutch translation Zwertocht tussen de sterren of
Citizen of the Galaxy
van Robert Heinlein
in which I started last Sunday after I bought it on Saturday
from bookshop Kruimeltje
for five euro. I read this book twice before (accoring to my
diary) on May 13,14, 1977 and March 13, 1982. Now I understand
again, why on those readings, I finished the book so quickly.
It is truely a very exciting story, but I am also surprised
by the depth of the story. The alternative societies that
Heinlein imagined in the book, look very realistic to me.
I wonder if it would every been turned into a movie.
This months interesting links
Movements
KMZ file of movements (incomplete).
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Sunday, March 1, 2009