Government: Underwriter & Referee Only, Please!

I used to think government ought to provide as much as infrastructure and assistance to its citizens. Such things like smooth paved roads, free highways, comprehensive health coverage, caring unemployment insurance, generous child benefit, free primary and secondary education, cheap – or free – university education, work training, generous pension, and so on. I thought this was to be expected from government; after all, government is supposed to be staffed by well-intentioned, intelligent people, right? Moreover, government is a representation of its citizens and as such is supposed to deliver what each citizen cannot individually get. Government in short should create a welfare state to ensure the welfare of its people.

This grand idea is nice and noble. I believed in it when I was a university student. One perspective I didn't have then was the perspective of a taxpayer. A welfare state requires a lot of money and it comes from taxpayers. It was easy for me to demand all the infrastructure and assistance from a government when I didn't have to pay it.

When I got a job, I found out quickly enough that a big chunk taken from my paycheque was tax. Something like 30%! My initial reaction was 'Well, it was time for me to participate in building our economy and welfare'. It went on for several years, and I learned that along with paycheque expenses also went up. Things like mortgage, car payment, clothing, entertainment, vacation, eating out, cell phone bills, and the rest. These expenses got me thinking: 'Wait a minute, am I not already participating in building our economy and welfare by making these expenses?' I started feeling the squeeze of a middle-class lifestyle where paycheque begets expense and things go around in a circle. Around and around ... you know what I mean.

Why then do I still have to pay a lot of income tax? Shouldn't it be more fair if my expenses were taxed instead of taking a big chunk directly from my paycheque? The pendulum swung to the other end as I thought about my situation. I started to wonder why there was no tax credit for healthy citizens who did not get sick for a year; wouldn't it motivate people to exercise and eat right? I started to wonder why the bank's interest rate were not high enough so that people were motivated to save? Government takes money, but seldom returns it. Apparently, government doesn't apply economics as the art and science of incentives to motivate its citizens.

This is when I started realizing that government may not be staffed by people who really understand that money does not grow from the trees. Moreover, political parties that vie for the position of government can promise all kinds of things during election campaigns. But who are going to pay for all these? You guessed it, taxpayers.

So now I have both perspectives: as a non taxpayer and as a taxpayer. On balance, I believe a welfare state will not create innovative, risk-taking yet prudent citizens.

An impoverished government will not also be able to do its main functions: underwriter and referee. I see government as an insurance company to protect its citizens against unpredictable, life-threatening forces such as traffic accidents, floods, tsunami and alikes. Even then, citizens should be able to exercise freedom to choose private insurance companies if their prices and coverages are better. As an underwriter, government should provide protection against invasion risk (defense role) and trade & manufacturing liabilities (if it wants to develop strong industry). Government should protect wealth and beauty of land and water. As a referee, government should settle disputes among its citizens and enforce any laws passed. Even then, citizens should be allowed to settle their disputes out of court if they so wish.

Mandi

Aku mandi jika aku capek kotor
Gemericik air buat aku tenang
Otak bisa berpikir lagi habis
Seharian angkat angkat

Aku makan lodeh jika lapar
Masakan istri tidak terkalahkan
Santan kelapa kuning kemerahan
Sayur segar ditemani tahu tempe

Aku baca jika aku butuh ide baru
Ratusan buku aku kurangi karena
Ikuti orang semakin tidak enak
Aku mau jalanku sendiri

Aku lari jika badanku ingin segar
Naik sepeda sampai kulit hitam
Sudah lama tidak naik gunung
Hidup singkat terasa terbuang

Aku sapa anak jika rindu peluk
Yang besar yang kecil asaku juga
Senang lihat mereka dekat
Satu saat pergi jauh bersama

Impermanence

Q: Does everything change?

A: Yes, around us. Within us. When I was a student, my political orientation was left-wing. As my children grew, my living costs grew too and I realized the costs have gotten more expensive: clothing, books, entertainment, food. I want lower tax and my political orientation is more right-wing now.

Q: I am not sure if left-wing and right-wing dichotomy is relevant now, given there are not many socialist countries that thrive. That by the way is a change and it will keep changing.

A: You're right. I haven't run for a month and yesterday I ran. My right knee now feels sore. If I don't keep exercising regularly, my knee changes to a weaker state. Nothing is permanent.

Q: Why is nothing is permanent?

A: Because at least this world moves in cycle. We were born, grew up, and will die. We often think of this cycle as something that moves in time. But cycle moves in space as well. Countries that were dominant - Iraq, Egypt, more recently Portugal and Spain - now are no longer. History can teach us a lot of things, if only we were willing to read and listen.

Q: Isn't it obvious?

A: It is, as a knowledge, but it is so difficult to practice it. We cling so much to what we have. Everything. As if things would not change. The other day as I pack my books for my new adventure, I found out I clung so much to my books. I had a hard time picking ones that are truly important.

Q: Ha ha ha, that's funny. And you certainly thought other people clung more to their stuff - be they jewelry, clothing, or food.

A: Precisely, I had previously believed I didn't have a lot of attachment. But I did. It is always easier to criticize other people than recognizing my own weaknesses.

Q: Do you suggest that to have no attachment is the sure-fire way to deal with impermanence?

A: Yes, I feel that way. Having no attachment to anything is like anticipating the impermanence that surrounds us. It is the most natural response to impermanence.

Why Mission Needed?

A: That's a good question. Let me try to answer that. I wouldn't dream any mission in life - I am certain - if I didn't have education. I would be happy doing the 9-to-5 thing, watching games and shows on teve, going shopping, going to sleep, waking up, and going on like that for the next 20 years. My world would be a happier place without education ... A funny thing to say, come to think of it.

Q: Education sucks then, it ruins the party, eh?

A: When people say 'ignorance is bliss', they don't bullshit. Educated society demands a lot of things, which makes me wonder why Canadian political election has always been about health care ...

Q: But isn't it trite to say your life needs a mission? I mean, everyone has a mission in his life.

A: Well, there are obligations, you know ... duties, then there are life missions. The fact that my wife and I are raising my kids and making sure they grow up well is not my life mission. It is my duty since no one else is willing to do it.

Q: And how about mission?

A: Mission is what I elect to do. I can choose not to do it, but I decided to do it. It becomes a mission. Thing I have to do because I want to do it. It starts with a desire and ends with a decision to do something.

Q: Wait a minute, ... so having kids can be a mission then? Right?

A: Yes, you can decide to have 20 kids as your life mission, for example. Let's see whether you'll like it, huh!

Q: But why do you need a mission?

A: The short answer is that I can't stand routine stuff. It's supremely boring and could define what a hell is for me. The long answer goes back to the idea of education. That once it opens me to the world of ideas, it is hard to go back and pretend life is only about what to eat and buy for today or tomorrow.

Q: Not only you're melancholic, but incurably romantic as well.

A: I am. I accept it as who I am.

Q: So, what's your mission?

A: I want to travel the world, to be alone at the mountain peak and to meet people everywhere. I want to have my own business. Be my own boss and take care of people who work for me. Take care of people I love. That would be great! That's my mission.

Q: I do too. I feel what you say. I like the people I meet at work, but I hate my job. It becomes stale and too routine. I agree having my own business will give constant challenges.

A: I don't think it would get easier with owning a business - being an employee is actually easier - but I need challenges.

Q: What kind of business?

A: It has to be something I am really good at. Not just any business, opening a restaurant or a bar. It is not about money only. It is about meshing things I want to do with things I am good at.

Interesting Word, Freedom ...

A: Yeah, I know, 'cause we never have one. One - or worse, thing - enslaves another. I still want to be in a better spot though?

Q: Whatdayameaan?

A: Since I know I can never have freedom, at least I want a noble master ...

Q: You're bullshitting, right?!?

A: No, I am serious. I purposefully pick my master so that I feel at ease when I am enslaved.

Q: Ha ha ha, that's deep shit, man!

A: No kidding ... I figure if I am at ease when I am enslaved, I gain my freedom. You see I think I am on to something here. That's what I mean by finding a noble master.

Q: Hah, you're not a stupid thinker after all; I've seen worse. I guess this is what you mean by 'living a life with a mission' in our last conversation ...

A: Yeah, you are absolutely right. My mission is my noble master. I think about this a lot, as you know, and I come to a conclusion that my life is worth-living if it has a mission.

Q: Different people, different missions, or none at all for some people, eh?!

A: Hell, yeah ... it's a free market, bro! It's what gives color to this world.

Q: So, you don't wanna be a preacher?

A: Well, I'd like to share about my mission, but why should I waste my time too much? I got my mission to fulfill, right?

Q: Aahh, this starts to click now. You're just a lazy person, then?

A: Whatdayameaan?

Q: Well, you won't lift a finger if you don't see a benefit.

A: Most definitely, but it's not because my mission is to maximize the benefit. It's a by product, you see ...

Q: Whatever, but I see more clearly now.

What Are You Looking For?

A: Happiness, but mostly freedom.

Q: But don't you find one already?

A: Yes, but it feels flat - kind of meaningless.

Q: What do you mean?

A: Well, I feel happy, but happy as in 'absence of sadness', not happy in a meaningful way.

Q: You are just melancholic, you should live a little. Go out and buy things. You will feel happy.

A: I could but it is predictable. You know, those stuff are boring. You go in cycle and you feel trapped.

Q: Then you are not looking for happiness?

A: I suppose, but you know I keep searching ....

Q: So, you want to find a meaning in your life?

A: Yes, I think that's it. I want my life to mean something. A life with a mission.

Q: You are asking too much. You live in an advanced country. All things that need to be done were done already. Why can't you just enjoy the party?

A: What party? I am struggling as it is, along with my millions of countrymen. I think what you said about 'all things that need to be done were done' kinda explain what happens with our election campaign. So far it's been quite civil, er ... quiet ...

Q: What you said was interesting though ... You wanted a life with a mission. Do you know already what?

A: Yes, vaguely, but mostly I think because I am just a shy person.

Q: You're kidding, right? If any, you probably talk too much. You need to think about it more, but don't think too long ... The train will not wait for you!

A: I know.

Area & Volume

My previous blog was on two lines intersecting and the intersection gives us a notion of inner product, a peculiar way to multiply two vectors. When we consider area of a two-dimensional plane, we need to define an outer product, which is another way to multiply two vectors.

An area of a section in a flat two-dimensional plane is shown in the diagram below.

When you work out the algebra for sinγ using the identity sin²γ + cos²γ = 1, where cosγ is obtained from the inner product expression, you will find the following result when a and b are two-dimensional vectors.

So, for sinγ we obtain an interesting expression: a₁b₂ − a₂b₁. I said interesting because the indices 1 and 2 corresponding to the first and second components of the vectors a and b are interchanged and for some reason a minus sign is produced. If we stay in 2D, we won't be able to see the beauty of this interesting expression.

To move into a three-dimensional space means we are concerned with volume. If we consider a parallelepiped volume below, we can define three vectors: a = (a₁,a₂,a₃); b = (b₁,b₂,b₃); c = (c₁,c₂,c₃), which form a frame for the parallelepiped as shown below.

Things get truly interesting now. We must extend by analogy the notion of inner product in 2D space to a 3D space:

a⋅b = a_j b_j = a₁b₁ + a₂b₂ + a₃b₃

The index j is repeated, and this implies that j runs from 1 to 3 and the terms are added. Using this definition, it can be shown, after some algebra, that

Area = [(a₂b₃ - a₂b₃)² + (a₃b₁ - a₁b₃)² + (a₁b₂ - a₂b₁)²]^1/2.

The area spanned by the two vectors a and b is a length of a vector - let's call it g - given by

g = (a₂b₃ - a₂b₃, a₃b₁ - a₁b₃, a₁b₂ - a₂b₁).

g is the most natural (simple) choice for this vector, whose length corresponds to the area, since g is perpendicular to a and b. There are other 5 possibilities but they are not perpendicular to a and b. Another interesting result is that the vector -g (i.e., opposite to g but equal length) is also a solution, that is its length also yields the area spanned by vectors a and b.

The common choice in applied math is to pick g (not -g) as the vector perpendicular to a and b by imposing an 'index permutation' condition. This condition basically says that a term 'a₂b₃' in g will have a positive sign, while a term 'a₃b₂' will instead have a negative sign, and so on. In the former, the positive sign comes up because the index 2 appears before 3, while in the latter 3 appears before 2. To regulate this sign assignment we define an index-permutation coefficient (its fancy name is Levi-Civita symbol).

An outer product of a and b (in that order) is equal to g,

g = a × b,

and the length of g is equal to the area spanned by vectors a and b. If we flip the order of a and b, we get

-g = b × a,

where the negative sign appears because of the reverse index permutation.

Once we understand that an area in 3D space is equal to the length of vector g, the volume of a parallelepiped spanned by vectors a, b, and c can be obtained simply, as shown by the diagram below.

The volume is equal to the inner product of g and c, and since g = a × b, we get the desired result,

Volume = c⋅(a × b).

Why does inner product of 2 vectors look like that?

The inner product of two vectors a and b is defined by

a⋅b = a₁b₁ + a₂b₂

where a = (a₁,a₂) and b = (b₁,b₂) are defined on a two-dimensional space.

Why does the inner product of these two vectors look like that? Is there any purpose at all to define the inner product like that?

The answer to this question shows the connection between vectors and geometry. More precisely, the inner product helps us obtain the angle between two vectors.

But there are two angles between these two vectors. The first angle is defined when we stack the two vectors one after the other. The symbols |a| and |b| mean the lengths of vectors a and b.

The second angle is defined when we coincide the starting points of the two vectors.

The two angles, α and γ, are actually connected when we look at the diagram below.

That is, their sum is equal to 180°. From the definition of the inner product, we can conclude right away that a⋅b = 0 if the two vectors are perpendicular to each other.

Kakek

Langkah diammu ingatkan aku

Bapakku yang sudah tak sabar

Cucu tinggal di tanah jauh.

Heh, itu saja yang kamu ucapkan

Waktu aku sapa kamu walau

Kita bertetangga bersebelahan.

Topi dan lagakmu persis bapakku

Diam tapi tak ragu tengkar teriak

Aku pun yakin kamu seperti itu.

Aku jadi terlena ingat bapakku

Kakek anakku punya banyak cerita

Sudah tua tapi tak mau diam.

Senyum dan mata membasah

Ingat saat kita siap berhunus

Anak bapak sama saja gila.

Aku pelan sadar kita tidak beda

Bapakku pasti senang bertemu

Cucunya: cermin hidup masih muda.

Jauh

Aku sudah berjalan jauh

Tak takut lagi bicara mati

Menghitung hari dan tahun

Pastikan anak istri terjamin.

Kerap aku jadi tak sabar

Karena aku ada di depan

Aku masih harus belajar

Mendengar raba merasa.

Aku sudah berjalan jauh

Tak takut lagi jatuh miskin

Pasrah hukum alam saja

Masih banyak harus kuraih.

Dulu kupikir ini yang kucari

Jadi pertapa menara gading

Sepi bukan sahabatku lagi

Aku mau jalanku sendiri.

Aku sudah berjalan jauh

Satu besar, satu beranjak

Mungkin aku kembali lagi

Tapi sudah, terserah mereka.

Lepas nanti kamu berdua

Kita teman dekat terbaik

Bukan aku letih dan penat

Tapi kamu harus berani.

Aku sudah berjalan jauh

Semakin tahu mauku apa

Tak mempan bujuk rayumu

Makin cinta dirimu saja.

Apa Yang Berharga Dariku

Anakku,
umurmu sudah enam tahun sekarang
    masih muda dan panjang jalanmu
aku sendiri baru melangkah tiga puluh

saat ini, sendiri
ibumu dan kamu jauh dariku

Kemarin aku duduk lama di taman
    dekat apartemen kita
menyisir pikiran dan rasa.
Teriakan riang remaja main baseball
   sepasang muda-mudi berlarian menangkap frisbee
      tiga anak kecil hitam dan kakeknya
duduk di bawah pohon rindang

Aku teringat saatku sendiri
empat tahun pertamaku.
    Tapi kali ini dahsyat rasa sunyi
menghantam dada.
    Rindu mendekap ibumu dan tawa dan tangismu

Sudah banyak aku dengar dan baca
apa itu hidup dan waktu.
Tetap tak bisa ganti
pengalaman sendiri.
Dengarkan apa yang aku ungkapkan
sebelum kamu baca dan alami sendiri.

Hargai kemerdekaan
    menyamai hidupmu
Karena dialah pembuka irama hari
dan nyanyi syahdu menjelang tidur.
Jangan bungkam dia sebelum semua indramu
mereguk penuh.

Hidup ini terlalu singkat buat
penakut dan pengecut.
Tajamkan niat
asah nalar untuk maju
memimpin mereka yang akan berbaris
di belakangmu.
Dengan menjadi nahkoda kapalmu sendiri
kamu akan mengenal lautan hidup.

Tirulah gandum, menatap sang mentari
badan tegak dan mata lurus
menyongsong, tangan terbuka lebar.
Biarkan mentari membakar rantingmu
karena hanya itu kamu bisa tumbuh.
Bulir jiwamu menjadi terisi energi
mengalir di tata surya.
Tapi jangan pongah dan lengah,
karena sungai di dekat rumah nenek buyutmu
tak mengalir jauh. Walau berderas lantang.
Sedang kali Brantas dan Bengawan Solo
membawa hanyut debu subur kawah berapi
sampai jauh ke laut. Hampir tanpa gemuruh.

Lalui keseharian dengan gairah dan semangat
sambut sapa selamat pagi, dengan dendang lagu kesukaan.
Tak usah malu dan enggan menari bersama hidup
karena kita toh akan dijemput sang maut.
Peluk dan cium dia
hirup semerbak aromanya dan berlarilah riang
di hari cerah atau penuh badai.

Cari kebenaran
nalar dan rasa menuntunmu.
Jangan ragu tanya atau malas pikir
karena orang lain akan menyita jiwamu
    gadaikan di altar jadi-jadian,
jika kamu tidak melangkah sendiri.
Bicara seadanya dan jujur
biar orang mengenalmu
seperti kamu kenal dirimu.
Tidak ada rahasia hidup yang tidak kamu tahu.
Dan tak usah ciptakan mitos dan misteri
karena hanya asingkan kamu
dari orang-orang yang mencintaimu.

Tidak ada yang lebih terhormat
dari kerja sehari penuh
cukupi dirimu sendiri.
Pelajari semua yang kamu temui
selagi masih punya waktu.
Jangan pernah bilang tidak bisa
sebelum kamu jatuh terseok berulang kali.

Tidak ada pekerjaan lebih mulia dari yang lain.
Karena kita hidup bersama, menghirup udara
meminum air, dan menanak nasi
hasil keringat orang lain
ramuan alam warisan nenek moyang.
Kalau kamu jadi pembesar atau orang pintar
Jangan buang muka dari orang-orang
menatapmu hormat kagum.
Kalau kamu jadi pegawai atau pekerja
jangan tundukkan kepala berdiam diri
ragu takut akan pikiran orang lain.
Karena hakikat manusia bukan pangkat dan gelar.

Hanya memberi, bukan mengemis
kamu menjadi kaya raya.
Hanya kegairahan, bukan keengganan,
kamu memetik kebahagiaan.
Hanya mencari, bukan pasrah,
kamu menggenggam kemerdekaan.

Anakku,
waktunya aku bekerja kembali
sudah duduk tiga jam menulis buatmu.
Kalau aku tidak bisa memberimu apa-apa
biarlah puisi ini menjadi
semua yang berharga dariku.

28 August 2000

Nuclear Reactor Basics

I had a conversation this morning with my two good friends. We're discussing Japan nuclear crisis following the 9.0 earthquake and tsunami. Radioactive materials are released into ocean and atmosphere, and I was left wondering how many kilograms of uranium material needed to power a typical nuclear reactor. Below are my estimates.

A nuclear power plant is powered by the nuclear splitting process (fission) of either natural or enriched uranium. Natural uranium has largely U-238, about 0.7% U-235 isotope, and a tiny amount of U-234. Enriched uranium has 3-5% U-235. Either natural or enriched uranium can act as nuclear fuel. The amount of heat liberated by one fissile U-235 atom is 202.5 MeV. Since 1 eV = 1.602 × 10^-19 J, 202.5 MeV = 3.2 × 10^-11 J. The atomic weight of uranium is 238 amu = 238 g/mol due to the overwhelming fractional amount of U-238. Since 1 mole = 6.02 × 10²³, the amount of energy liberated per kg of natural uranium due to U-235 fission is 134 is 566.6 GJ/kg.

A large power plant typically produces about 1 GW electrical power. Per year, this means an energy production of 31,536 TJ. Hence, the natural uranium needed to produce this much energy is 55.7 metric ton. But, this much uranium is for a 100% heat-to-electricity energy conversion efficiency. A more realistic efficiency number is 40% – as I expect the nuclear power plant will use high temperature steam to drive turbine blades – so that a more realistic estimate of natural uranium required per year for the 1 GW power is 139.3 metric ton.

The estimate amount for the enriched uranium will be 4-7 times less due to its higher U-235 composition, but the numbers of U-235 atoms required in either fuel types are the same.

Neutrons produced by the U-235 fission are also captured by the more abundant U-238 leading to the production of fissile Pu-239 (plutonium). The amount of heat released by fission of one Pu-239 atom is 207.1 MeV, which is comparable to the heat produced by fissile U-235, and is used as well for power generation. The Economist (31 March 2011) reported that Pu-239 was detected in soil samples taken from the surrounding area of Fukushima Daiichi nuclear power plant.

The Fukushima Daiichi nuclear power plant has 6 units with a combined electrical power output of 4.6 GW. They are boiling water reactor (BWR) type, where cooling water passes through the hot fuel and the steam is directly produced from the water.

Solar Thermal Heater: Molten Salt & Synthetic Oil

I came across a useful article on solar thermal power plants by MIT's Technology Review. It summarizes efforts of large energy companies to harness solar energy by capturing the energy through evaporation of a suitable working fluid in a Rankine cycle. The resulting steam from the evaporation is used to drive turbine blades, which then converts the steam's energy into electricity.

Siemens wants to use a mixture of molten potassium & sodium nitrate (molten salt) for the solar thermal power plant it designs and manufactures. The problem is that this molten salt freezes at around 220 °C. Kilometer long pipes used for this large scale power plant can be clogged by solid chunks since it is also difficult to control the pipe temperature to be always above the freezing point 24/7. Heat loss - radiative and convective - can be significant and freezing risk is real. A large scale power plant would require a heat storage to regulate the molten salt temperature.

This limitation also means that molten salt is not a good material for small scale power plant. The daily fluctuations of solar intensity makes molten salt unattractive as a result.

Solar thermal energy conversion method is more promising than solar photovoltaic since photovoltaic researchers still muse about 14 cents/kWh price, while solar thermal technology already has 13-20 cents/kWh pricing.

Another material used for solar thermal power plant is synthetic oil. The problem here is the temperature cannot exceed 390 °C since the oil will break down.

If I Won't Quit I Can't Win

My friend gave me $40 to gamble in a casino after his win from a jackpot terminal. I spent the first $20 and won. I have never played at casino before and have to say it can get addictive. There are those bright lights. There is also my feeling that maybe the next turn will make me win more.

The bright lights symbolize a lure any casino lays on anyone to visit and spend money. The lights never go off and daylight seems to go on forever. The buffet restaurant inside it offers cheap, good food. People - I think - figure why not go to casino and have a meal there. The money saved from the meal can be spent for gambling. Who knows maybe the saving can turn to a jackpot. I bet the reasoning is like that, pun intended.

The feeling that a win is just a game away is what keeps people coming back. I tasted my first ever win and wanted to get more. I know how easy it is, and it is exciting. The taste of winning makes me want play more. I get to know the odds, so I think.

I figure the odds are about 50-50 on a mechanical terminal game. Putting a $20 on a $5 game allows me to play 4 times. And the odds of winning once from the four games are very slim to even break even. I therefore decided to spread the risk by having at least 10 games. You see I thought I knew the odds could be tilted in my favor, if I was just smart enough. This feeling can become a reason to come back.

My friend, who gave me $40, has won a lot more several times before. It is possible to win more than once. He said he knew people who made a living from gambling, especially in Las Vegas. These guys are professional and they learn how to assess risks without emotion even when they play. They bet a lot and know when to quit by accepting losses. Some people can do this, but I suspect a lot more people cannot.

The question is thus whether I can control the urge to win a lot more than what I have. When I played the second $20, I lost. I concluded I had to quit if I wanted to win. Even with this knowledge, I kept playing until I lost $100. I still came out on top by a slim margin because I finally told myself to quit.

Harga Tak Berbanding

Aku kaget diberitahu kalau harga beras di Indonesia sekitar Rp. 8000/kg, atau sekitar US 90 sen/kg. Pendapatan rata-rata per orang di Indonesia US$4380 per tahun, atau sekitar Rp. 39 juta/tahun, yang bisa dipakai untuk beli 4870 kg beras.

Pendapatan rata-rata per orang di Canada US$39033, sementara tadi aku beli beras 9 kg seharga US$25. Jadi pendapatan rata-rata per orang di Canada bisa dipakai untuk beli 15613 kg beras.

Kekuatan beli orang Canada rata-rata 4 kali lipat lebih kuat dari orang Indonesia. Atau dengan kata lain, semestinya harga beras di Indonesia Rp. 2000/kg agar daya beli rakyat Indonesia setara dengan daya beli rakyat Canada.

Ketimpangan harga Indonesia-Canada seperti ini aku temui sehari-hari sewaktu di Indonesia tahun lalu. Harga secangkir kopi di Starbucks di Jakarta sekitar Rp. 20000, dan ini sama persis dengan harga secangkir kopi di Canada, yang sekitar CD$2. Herannya, kok banyak di Jakarta yang beli kopi di Starbucks?

Aku gak menyalahkan perilaku konsumen yang keliru karena aku melihat ada keuntungan ngopi di Starbucks. Duduk lebih enak dan tenang, ruangan lebih asri dan dingin, mau baca buku dan cangkruk gak diusir.

Harga-harga di Canada menurutku lebih mendekati ekuilibrium karena laju inflasi sangat rendah (1-2% per tahun). Masuk akal jadinya berpendapat masih ada banyak peluang bisnis di Indonesia untuk mengisi celah beda harga agar sampai ke titik ekuilibrium harga.

Making Sense of Heating Cost

Body heat is retained when using sleeping bag: A self-heating technology.

Living in Canada means surviving in very cold winter, unless you live in Vancouver or surrounding areas abutting Pacific Ocean. Canadian winter is harsh; temperature can dip to below -20°C regularly and it's been said to make Canadians strong quiet type. In the province of Ontario, it is slightly milder, about -10°C but the wind is fiercer. In Alberta, we get chinook ("snow eater") wind every 2-3 weeks, so the temperature can change from -20° to 5°C in a day and a week later it will drop to -20°C again.

At a household level, the winter means Canadian families need to spend money to heat their houses. Typically, a house is kept at about 21°C to make everyone feel comfortable (i.e., not wearing sweater at home), so there could be a 50°C temperature difference between inside and outside the house. The monthly heating cost can range from $90 in summer to $200 in winter. What is interesting is that most of this heating cost comes from administrative (30%) and delivery (30%) charges.

It is also interesting to notice that the retail natural gas price in Canada remains low, at about $4/GJ. (GJ = Gigajoule = 10⁹ Joule; Joule is a unit of energy, named after James Prescott Joule). How can I say $4/GJ price cheap? An old, energy-hungry fridge typically needs 639 kWh per year = 2.3 GJ per year. This means natural gas priced at $4/GJ could power this fridge for one month for less than $1. Another benchmark I can compare to is the electricity price in Canada, which is 8 ¢/kWh. The natural gas price of $4/GJ is equal to 1.4 ¢/kWh. It is not surprising Canadians are not that interested in energy-saving measures. It's the economy, stupid.

Note: A more familiar unit of energy is Watt (named after James Watt). 1 Watt = 1 Joule per second, so that 1 kWh = 10³ W × 3600 seconds = 3.6 × 10⁶ J = 3.6 MJ. (MJ = Megajoule.)

When the administrative and delivery charges are included, the natural gas price becomes roughly $8/GJ. The energy needed to heat an average-sized house per month is roughly 24 GJ in winter; thus the cost is about $200/month in the winter. Okay, so the numbers add up and we now understand our monthly natural gas bill.

The household 24 GJ/month heating budget is to compensate mostly for thermal radiation and convection heat loss from the house to outside. Thermal radiation loss from a house is proportional to the surface area of the house in contact with the outside. The larger the house, the larger the area becomes. A typical house in Canada has a surface area of 300 m². Using the Stefan-Boltzmann law,

ΔP = 4 ε σ A T³ ΔT,

we can figure out the amount of thermal radiation loss ΔP which depends on emissivity ε and outside temperature T (say, -23°C = 250 K). ΔT is the temperature difference which is about 7°C (roughly the difference between the exterior wall's and the outside's), while σ is the Stefan-Boltzmann constant. (Emissivity ε of the house exterior wall can be assumed to be 1, so we don't need to worry about it.) The numbers work out to be ΔP = 7.0 kW, or 18.1 GJ/month.

In addition to heating the house, we need to heat water for shower as well. The heat capacity of water is 4200 J/kg per degree Celcius. A person can use water up to 160 litre = 160 kg per shower. Considering a more environmentally committed family, a family of four might use about 450 litre for shower, cooking, and washing dishes. Canadians shower once a day, so the amount of energy needed to heat the water from 10°C to 60°C is about 95 MJ. In a month, it will be 4 GJ when factoring furnace efficiency. The water heating energy budget is about 17% of the total 24 GJ/month

The remaining 1.9 GJ/month could be attributed to convection loss and thermal contact loss with the ground.

The 7 kW heat emitted by a typical house is a waste heat. Your house is a light bulb, LOL. Your carbon footprint. This heat can be tapped and converted into electricity, but thermoelectric technology is not cheap.

Budaya Cangkruk

Aku anak kampung Surabaya. Waktu SD aku sering main di jalan: main petak umpet, gundu, baca komik. Bapak-bapak duduk merokok di emper jalan sambil cerita ini-itu. Tidak jarang ibu-ibu ikut nimbrung. Aku masih ingat karakter tetangga kiri-kanan rumah. Aku ingat pernah main sepatu roda jam 8 malam dengan teman-teman sekampung. Saking ramainya, kita diteriaki satu ibu tetangga yang memang tukang labrak dan disiram air got. Untung saja pakai sepatu roda jadi bisa kabur cepat.

Budaya cangkruk (nongkrong pinggir jalan) ini oleh sebagian orang dianggap kampungan. Kalau maksudnya: hanya orang kampung yang melakukan ini, ya benar juga.

Orang Canada berarti juga orang kampung. Orang Canada - terutama yang muda - suka sekali cangkruk. Mereka cangkruk di pub untuk minum bir, makan sayap ayam atau nachos, sambil ngomong ngalor ngidul. O ya, jangan lupa pub ini juga dipakai untuk memprospek cewek/cowok yang ingin mereka dekati. 

Jadi jangan disangka cangkruk gak ada di Canada. Cangkruk terpaksa dilakukan di pub karena cuaca Canada dinginnya minta ampun. Di Calgary musim dingin dari November sampai Mei (6 bulan cak!) dan suhu udara bisa turun sampai -30°C. Lha siapa yang mau ngobrol ngalor ngidul di emper jalan?! Bisa mati kedinginan dalam 5 menit.

Jadi tolong deh, jangan dihubungkan budaya cangkruk dengan sebagian orang yang bilang kurang produktifnya orang Indonesia. This is bullshit.

Satu budaya lain yang berhubungan dengan cangkruk adalah kenduri. Saat 17 Agustusan, gang di depan rumah ditutup dan tikar digelar berlembar-lembar. Kita duduk bersama dan menikmati makanan yang disiapkan ibu-ibu yang tinggal di gang. Satu kenangan manis yang tidak ada gantinya.

Di Canada, suasana kampung masih bisa dirasakan kalau tinggal di apartemen. Kita masih kenal tetangga karena lorong lantai menggantikan gang dan kita saling sapa. Suara anak kecil terdengar dari balik dinding. Kita masih ketemu waktu cuci pakaian. Apalagi di apartemen mahasiswa: ada tetangga yang bisa dititipin anak kecil, ada yang jualan makanan. Seperti kampung di Indonesia.

Saat aku pindah ke kompleks perumahan waktu SMP di Surabaya, aku tidak pernah lagi temui budaya cangkruk. Yang cangkruk cuma satpam dan tukang becak di pos ronda. Rasanya kurang hidup dan tiap-tiap keluarga sepertinya hidup sendiri-sendiri. Ini yang terjadi di hampir semua perumahan di Canada. Kita hidup sendiri-sendiri. Ada sih seperti balai RW - namanya community association centre - tapi kurang akrab karena tidak ada spontanitas. Semua pakai format rapat, jadi kalau ngomong harus hati-hati.

Hiburan cerita tetangga yang sering segar lucu jadi hilang karena spontanitas hilang. Cangkruk hilang dan diganti acara melototin teve. Payahnya banyak acara teve yang membosankan. Ada sih yang asyik; waktu di Indonesia aku suka lihat Take A Celebrity Out-nya Choky Sihotang atau Bukan Empat Mata-nya Tukul Arwana. Selebihnya bikin angop (ngantuk). Di Canada juga ada acara teve yang bagus: Seinfeld (rerun euy), House, Criminal Minds. Budaya cangkruk diganti budaya melototin teve.

Aku sih lebih senang cangkruk. Cerita lebih nyata dan aku mengenal karakter orang yang beragam.

What to Study at University?

My teenage son and I regularly discuss what he'll study at university. He plans to apply next year and I remember when I was his age I didn't know what to study. I knew what I liked but I never asked harder than that.

I tried to not repeat my mistake. I suggest him to apply to a program that suits his natural talent. We also discuss job paths. To ask how and why people become professors, businessmen, designers, engineers, and others. He gets bored sometimes when I want to discuss this issue, but he knows it's important.

I learn that parents - me included - are very invested in their children's higher education. It is difficult to separate what I want for him from what he wants for himself. If I am not willing to admit this, I am likely to repeat my mistake since my son and I share similar personal traits.

Undergraduate programs we consider in our discussion are

1. Engineering. He'll learn to memorize and use math equations, but he won't know how to get them. He'll have to study with his friends to survive grueling homework & exam schedule. Going into a program means specializing in a specific area of engineering. Mechanical engineering is the broadest and safest. Working as an engineer in the first 5-10 years means doing routine maintenance, design, or sales. Above average math and physics skills are needed, but it is not necessary to be creative. Experience matters since engineers learn by induction.

2. Mathematics. He'll learn abstract problem solving by pure reasoning and without specific area of specialization. He'll have to study alone most of the time. There is no team effort; if he doesn't get it, he will not understand it. Studying math often means also taking a minor in business or something else to make job prospect better. Above average math skills are a must and creativity is required. Experience does not matter since mathematicians learn by deduction. Engineer makes money by specialization and experience, while mathematician by generalization and quick mind.

3. Physics. He'll learn how to use math to solve science and engineering problems. Unlike engineering though, physics offers little specialization. But most what we know in engineering come from physics. He can think independently and analyze all sorts of real-world problems. Experience matters but deduction matters more. In the long run, knowing physics is more useful than engineering even in engineering companies. Taking math, however, is more general than physics since business problems do not follow mechanics axioms.

4. Business. He'll learn how to draw up a business plan when starting a company, to raise capital, to read financial statements, to understand tax and business laws. He'll learn how to run a business, the ins and outs of money. He and I agree that these skills are best studied by practice. I personally see little point of taking business courses if I am not going to use them now. He does not want to specialize in tourism, accounting, or others; they seem too narrow for him.

5. Design. I don't know any undergraduate program on design. I took a design course when in undergrad and I have to say it was not that useful unless I know physics well so that my design can be functional. Design is also part arts. If he does not draw and sketch, then he has no talent in design.

6. Economics. If the study route is mathematical economics, then studying math seems to give a better foundation for economics study. If the route is economics and one of social sciences - political, history, geography - then he'll have to read a lot. He seems more a thinker than a reader. He would waste his math talent as well.

Rakyat Jalan Sendiri

Density

Water crystal (ice).

A basic formula for density of a solid is to weigh its mass m for a given reference volume V and then to divide the mass with the reference volume to yield density ρ. Because a crystal is constructible from many unit cells due to periodic arrangements of atoms, we can use the volume of a unit cell as the reference volume.

There are different unit cells for different crystals, depending on how the crystal's atoms organize themselves spatially. The number of atoms per unit cell, thus the mass of the unit cell, and the unit cell volume are difficult to predict. Experimentally, they are determined mainly from x-ray diffraction, which is also not straightforward.

Let us consider a simpler situation. Suppose a solid has two atoms, A and B, i.e., an alloy AB, then the density can be thought of as equal to

ρ = (m_A + m_B) ⁄(V_A + V_B).

It assumes that we know the unit cell volume V_i for atom i and the number of atoms i within each unit cell volume. It further assumes that the alloy AB adds the individual volumes from atoms A and atoms B to produce the alloy. This is not always the case, which is often surprising for many students. If atom A is much smaller than atom B, then atom A can occupy a tiny space–interstitial site–available between nearest neighboring atoms B. In this case, the density of alloy AB is better approximated by

ρ = (m_A + m_B) ⁄V_B

since atoms A only increases the unit cell's mass. Unfortunately, the formula

ρ = (m_A + m_B) ⁄(V_A + V_B)

and its equivalent expression

ρ = (C_A ⁄ρ_A + C_B ⁄ρ_B)^-1,

where C_A = m_A ⁄(m_A + m_B) and C_B = m_B ⁄(m_A + m_B), are often used indiscriminately. The unit cell volume additive property should work well only for atoms A and B that have the same crystal structures.

The formula

 ρ = (m_A + m_B) ⁄(V_A + V_B),

however, can work well when A and B refer not to atoms, but to phases. Two phases can coexist and each contributes its mass and volume. Both mass and volume are thus additive. The equivalent expression

ρ = (C_A ⁄ρ_A + C_B ⁄ρ_B)^-1

then requires us to determine the density of each phase separately. C_A and C_B are now determined by the lever rule.