I am quite excited about the upcoming Hackaton
event in Zurich, which I will attend. I've been learning a whole lot more about
functional programing, and this event is all about Haskell and hacking. While
I'm not really working on a huge project that I plan to present on the Hackaton
like others are (for example the Utrecht Haskell Compiler), I hope this to be a
great experience.
Currently I'm working in a team (of 2) on an interpreter for a toy language
very much resembling lambda calculus, and I hope to do some advances during the
Hackaton weekend. I am responsible for the evaluation strategies that will be used in this language
(ideally more will be supported, and the evaluation strategy will be a command
line parameter), and also for garbage collection.
Then, I will spend Monday and a part of Tuesday to go sight-seeing around
Zurich.
POST#0079 2010-MAR-2
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When a doctor prescribes a medicine, the patient has to take a number of
pills every so often. My grandmother is very old and must take 5 different type
of pills, each at a specific time of day. It's easy to forget and make
mix-ups – there should be a mechanism to help patients remember. Here are a
few ideas from the top of my head:
- Electronic: you have a watch or a pager-sized device that keeps beeping
until you confirm you've taken the pill. Disadvantage: I bet it would be a pain
in the ass to program it. Some healthy people can't handle electronic watches,
let alone ill people handling more complex technology.
- On paper: have the doctor print a table with check-boxes that you check each
time after taking the medicine. When prescribing drugs, instead of writing with
a pen (doctors have terrible writing anyway), they could just enter some
information (how often take the pill and for how long) and generate a timetable.
This way it's more fun and you can know for sure when you've forgotten to take
the medicine. Additionally, there is a feedback mechanism – you know if
you're improving or not when looking at the table.
This idea is based on the fact that checklists tend to reduce mistakes on
average. In hospitals, the number of accidental deaths in surgery has dropped
after nurses went through a checklist during the procedures. In what other areas
could this idea be applied? What are the downsides to checklists?
POST#0078 2009-AUG-10
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On August this year I'll be moving in Utrecht, Netherlands (for at least two
years) to study „Software Technology“ at Utrecht University. I'm really
excited about the things I'm going to learn there, and also about the fact that
I'll be surrounded with people having similar goals. I'm leaping into the
unknown here, in the sense that everything about Netherlands is unfamiliar, but
I am absolutely convinced it's going to create a lot of opportunities for self
improvement. The Dutch language is somewhere in the middle between English and
German, it's not easy to learn, but I can already say useful simple things
like „How much does that cost“ or „I am going to eat something“.
Anyway, all the courses will be in English. The Software Technology research at
UU is mostly related to functional programming and programming languages in
general from what I can tell, and I look forward to getting started!
POST#0077 2009-JUN-20
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Recently I remembered a puzzle I thought about a few years ago: „How do
rail car wheels manage to go round the curve?“. My friends and I, we were in a
train returning from a trip to the mountain. The train had a small incident,
something related to a short-circuit and electric failure: there was a bolt of
electricity which could be seen from under the train reaching a considerable
distance and touching a nearby house. The train came to a stop and there was
some smoke, but we were fine and we got back home safely. Oh yes, going back to
wheels, well, this event made us more conscious that we are actually traveling
in a train, on a set of wheels on a track, and someone posed the question.
Take a normal car, the one that can be driven on the road. Have you observed
that, while you're inside it, when the car steers, a part of the vehicle moves
more than the other? Consequently, when in a curve, some of the wheels have to
roll more than the others. To make this possible, cars are equipped with
differentials placed between them on the axis, allowing wheels to turn
independently one from another.
Rail vehicles, however, use no differentials: the axis and two wheels are all
connected in one piece. This shows that the problem of trains negotiating curves
is not as easy as one can initially think. My first guess was that tracks are
tilted in curve, allowing trains to bank when needed. It turns out that this is
true, this type of curves are called cants1. They allow trains to
change their direction while maintaining a greater speed. However, we're not
done yet, there's something more at work…
Another instance of curved tracks I observed is that which is used by
tram-ways. There is at least one place in Bucharest where the tracks lead trams
in a tight curve (it's actually a U-turn at the end of the line). They slowly
pass through it, making a lot of noise resulting from the friction of metal. In
this case, the wheels are spinning at the same speed, except superelevation (or
banking) and the centrifugal force cause more weight to be placed on the inside
wheels. Since there is less force placed on the outside wheels, they skid over
the rail (producing the friction noise).
But leaving the trams aside and going back to trains, the most interesting
fact, seems to be this one: the wheels and track have such a geometry that, as
the car enters a curve, the lateral displacement causes the rolling radius of
the left and right wheel to change. This means that the wheels start to behave
as a cone rather than a cylinder, allowing the car to steer freely through
the curve.
So yes, have you ever wondered why are railroad wheels shaped like that? it
seems that indeed there is a purpose to the geometry of the wheels and the rail
profiles as well.
1: „http://en.wikipedia.org/wiki/Cant_(road/rail)“
POST#0076 2009-JUN-2
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„Sir, the following paradigm shifts occurred while you were out“,
announces the secretary to its returning boss in a the now classic cartoon related to the Singularity, the moment when even the
most intelligent human will be surpassed by a machine in all ways.
If we are to trigger this event, then our own brain is a good starting point.
Just like that of humans, the artificial brain will probably have to learn
everything about reality and solve the problem of interacting with the
environment. In contrast with us, however, it will have to find other ways to
get experienced, since it will probably be difficult for it to pass through a
genuine childhood.
Arguably, the artificial intelligence could learn everything just like a
newborn, perhaps through special training. But will that be of much value? Would
it result in something more than an average human? In my opinion, it would be
necessary to supplement the processing power and hardware resources that support
the artificial brain with sensory experience required to write, say, a poem
about a tree. This way, it would be something along the lines of a supercomputer
with a character, possessing two types of knowledge: the first one, common
knowledge would include information about every subject, and perhaps every
existing taxonomy – and the second one would be subjective knowledge,
allowing for fuzzy connections and associations which can only be created
through personal experience.
But what is a brain, really? Is it just the sum of all its neurons, a
collection of automaton cells working together in a predictable way, or is it
something more? To attempt to answer this, we could start by looking at how the
brain is formed. It may be safe to consider it pretty much empty at birth, with
not much in it – other than perhaps some instincts.
In becoming sentient, however, the brain is dependent on its surroundings. It
is quite literally their reflection, since it considers true whatever it
observes and predicts about the environment. If you look at a tree, for example,
you recognize it's a tree but would a put-together simulation of neurons
understand that? The simulation didn't go to kindergarten, it doesn't know
stories with trees, it hasn't seen movies with trees, it hasn't seen a tree
before. In order for it to be effective, the association between the word
„tree“ and the experience of perceiving it through all the five senses would
have to become possible.
In a story I read (but unfortunately no longer find on the Web to credit the
original author), after the extinction of Man, two computers remain, created
with the purpose of serving mankind and solving problems such as building
cities. A newly created machine, however, is curious about the nature of
humans. It studies all the artifacts it finds and gathers all the possible
information about them, and after doing so it reaches the conclusion that the
way to become human is to transfer itself inside a human body (which it does,
then takes over all the other machines).
Ultimately what we would like to possess is an artifact having intelligence
and processing power superior to our own, combined with a relentless occupation
of this virtual mind on how to solve our problems and make new discoveries, and
to elaborate new scientific theories. Of course, we would ask it far more
significant questions than „Answer to the Ultimate Question of Life, the
Universe, and Everything“, to which everyone knows the answer is 42, as Douglas Adams tells us. In parallel to the Deep
Thought supercomputer imagined by the author, our Singularity intelligence will
have to allocate resources (energy, time, materials) to find answers to our
queries about reality.
POST#0075 2009-MAY-8
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Regarding the previous post about Why should marijuana be kept illegal, it would be interesting
to note that Portugal experimented with a policy of decriminalizing not only
marijuana, but other drugs as well. While this doesn't mean it's legal, it does
mean it put the focus on helping users overcome the problem. The result was:
„Compared to the European Union and the U.S., Portugal's drug use numbers are
impressive. Following decriminalization, Portugal had the lowest rate of
lifetime marijuana use in people over 15 in the E.U.: 10%.“ (Source).
POST#0074 2009-APR-27
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There's an interesting article about the illegal use of certain types of brain stimulants in order to boost brain activity. It's a
lot of text, but it's worth reading everything.
Often we are distracted and cannot concentrate on our work (whether is for
the job or for studying). On one hand, it is moral to use medicines and
chemicals to alter our body chemistry and improve our life. Coffee for example
is considered a performance booster for many. On the other hand, is it really
worth the risk to pump oneself up with this stuff just to be able to
work more?
POST#0073 2009-APR-23
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When creating a new database model, I always prefer to use the singular form
when naming entities. For example, instead of using „customers“, I like
using „customer“. It is in my opinion consistent with OOP programming.
When dealing with database tables, as beginners we think about them in the
first way it comes to mind: as a table drawn on paper, or maybe as a HTML table.
The table we first imagine is likely to have a header (the column names) and
rows (each one for every entry in the table). However, there is a different way
of looking at them. Each table could be seen as an Entity. An Entity
represents a template, such as a „customer“, just like a Class is a template
for an instance. It makes then sense to use the singular name when creating the
table in this case.
This is because, when creating classes, it's much more intuitive to create a
single customer with:
$object = new Customer();
rather than with
$object = new Customers();
Continuing this train of thought, the table columns are no longer columns,
but are properties of the object. A database table has columns just like a
class has properties. The semantics of NULL value for properties of a record:
the object doesn't have that property. So, when we declare a field as
Nullable, we are actually saying that a record for that entity can be
instanced even without a value for that property. We could retrieve a
nonexistent property from a record, and that will also return NULL. So, for a
certain record, a non existent field and a defined one (but NULL one) should be
identical from the API point of view. However, when we do in MySQL
something like:
SELECT `inexistentColumnName` FROM `customers`;
we get the following error:
#1054 - Unknown column 'inexistentColumnName' in 'field list'
and there is no setting to control whether we can accept those columns or
not. But because we still want to see the NULL values at work, we can create a
test database with a couple of tables, after which we will use the LEFT
JOIN query:
CREATE TABLE IF NOT EXISTS `a` (
`idA` int(11) NOT NULL,
`fieldA` int(11) NOT NULL
);
INSERT INTO `a` (`idA`, `fieldA`) VALUES (1, 111), (2, 222);
CREATE TABLE IF NOT EXISTS `b` (
`idB` int(11) NOT NULL,
`bField` int(11) NOT NULL
);
INSERT INTO `b` (`idB`, `bField`) VALUES (1, 555);
Having created these data structures, we now just query the a
table using a LEFT JOIN with the b table. What this translates into
is „Show me all the records from a that have an idA
value that is found in b.idB“. The „LEFT“
actually says „And also return the records from a that have no match in
b“:
SELECT * FROM `a`
LEFT JOIN `b` ON `a`.`idA` = `b`.`idB`;
The query returns:
| idA |
fieldA |
idB |
bField |
| 1 |
111 |
1 |
555 |
| 2 |
222 |
NULL |
NULL |
So, now we should have our results, observe the NULL values, which in this
context could be said to mean „This resulting record doesn't have the
properties idB, bField“. After seeing how database
tables and classes in OOP are analogous, it should be even more clear that we
should name our classes and database tables in the same way. As you work with
legacy applications and with other programmers, you learn to accept the plural
as a different naming convention, which is okay as long as there is consistency.
A few problems may arise only when having to deal with a mix of plural and
singular names.
POST#0072 2009-APR-22
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When starting a business, or any sort of enterprise, one can get into a great
state of mind and get excited from a variety of books that teach the rules,
presented as a sure way to guarantee success. This exists in programming too,
it's also known as the silver bullet, either in the form of books about
programming methodologies or in the form of software components and
frameworks.
But how much of the success is attributed to a specific method and set of
rules and how much to other factors, such as pure chance or something else, not
so glamorous? This is a question raised in Luck Inc.
It seems to me that the conclusion is that the best way to learn programming
or doing business is to just go out there and do stuff. The more you do, the
more you will learn.
POST#0071 2009-APR-20
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I was brought up in a religious country. Even now, in Romania, religion is
quite a big deal. Since now we're close to Easter holidays, you should know that
foreigners witnessing the orthodox tradition are surprised by the amplitude of
the events happening on Easter day. Basically everyone goes to church, listens
to the priest's hypnotic discourse, and lights up candles, making sure to
„take the light“, that is – to light their candle from the „official“
candlestick (or other candles as long as they are lit from there).
I have kept thinking and writing in the past about the arguments against
religion, but never why it's useful in the first place. It's sometimes
required to think from people's perspective, so here it is – cases where
I think religion could be a positive thing:
- Missionaries are the first to intervene in a third world country, wherever
there is a society needing this, even if it costs them their lives – they try
to educate people and get them to coexist peacefully.
- Sometimes (not so often today), people or groups of people are found in
situations where there is no visible way out. Religion helps them cooperate in
difficult settings and gives them hope to overcome hardships easier. It also
eases the psychological pain when sacrifice is needed (for instance, there are
40 virgins waiting for you in heaven if you die). This may explain the
emergence of religion through an evolutionary standpoint: the communities that
were supported by a religious belief may have acted in bolder ways, and
therefore had greater chances of survival.
- When someone dies, the priest giving the mess somehow provides comfort. This
is something I experienced. I guess it has to do with the superstitious nature
of humans. For example, think of a disgusting insect, but made of chocolate.
It's not a real insect, you know it's edible, but would you easily eat it? In
the same way, I guess priests provide some comfort for the loss of someone –
somehow they appeal to our superstitious self, telling us the deceased are in a
better place.
In conclusion, we are fortunate that today we are living a better life,
closer to the truth, and in chance there is a God, then it's most probably
something stretching a lot the definition that religions give of God.
POST#0070 2009-APR-15
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