It can only be female crime fighting goats swinging through the city, as they'll be shooting web from their udders. And then the comic books will get hold of this idea and..... oh god...... need brain bleach badly!...
OK, so possibly it takes fewer R/C aircraft than geese to take out an engine. Then you wave a magic wand and say maybe the other engine will stop too. Losing one engine does not cause the other to fail, despite your appeal to 'additional stress'. Twin jets are able to fly with one engine. To be certified, they must demonstrate they can safely fly on one engine during the most stressful period of flight (a single engine failure late in the take-off roll.) They can also fly safely for a long time on a single engine. With appropriate safeguards, they are certified to do so for up to three hours (ETOPS-180) and coming soon, for over five hours.
Thanks. Is this why there is so much emphasis on 137Cs in the Fukashima aftermath? Lots of nucleotides must have been released, but media reports only talked about two, and I've been wondering why that was.
For the purpose of this post, I'll accept that they can convert protons to neutrons as described, although I'm very dubious about this.
Here is a table of nickel isotopes. Here is the first source I found for neutron cross sections of nickel isotopes (pdf). (See figure 12, look at the left hand side of each 'destruction channels for ??Ni' plot for what low energy (thermal) neutrons will do.)
Cross sections are in barns, and are approximate as I'm eyeballing them off a logarithmic scale. 58Ni [stable, 68% abundant] (0.006 barn) -> 59Ni [-> 59Co, 76000 yr half life] 59Ni [unstable but long lived] (0.02b) -> 59Co [stable] or (0.005b) ->56 Fe [stable] or (0.004b) -> 60Ni [stable] 60Ni [stable, 26%] (0.006b) -> 61Ni [stable] 61Ni [stable, 1%] (0.002b) -> 62Ni [stable] 62Ni [stable, 4%] (0.006b) -> 63Ni [->63Cu, 100yr] 63Ni [unstable] (0.001b)-> 64Ni [stable] 64Ni [stable, 1%] (0.004b) -> 65Ni [->65Cu, 2.5 hr]
None of the cross sections are hugely larger than the others, so all these reactions will occur with reasonable frequency. So irradiating nickel with thermal neutrons, you are going to produce radioactive 59Co (76000yr), 63Ni (100yr) and 65Ni (2.5hr). The 65Ni isn't a problem - turn off the reactor, wait a couple of days, and it will all be gone. The 59Co is only a bit of a problem - with such a long half life, it isn't very radioactive. The 63Ni however is nasty. Like 137Cs (30yr) from the Fukashima reactors, the half life is short enough to be quite radioactive but long enough that you can't just wait it out. Finally, the nickel won't be 100% pure, so you have to worry about what neutron irradiation will do to the impurities.
The 65Ni means when you turn off your reactor, it will continue to produce residual heat for hours.
The article gives the impression that weak nuclear reactions aren't dangerous, but this is not so. If it were, nuclear reactor waste wouldn't be dangerous.
This reactor will be producing ionizing radiation when running (mostly gamma rays, some beta rays mostly from 65Ni decay, and a tiny amount of alpha particles from 59Co(n,a)56Fe.) This will require some pretty heavy shielding to stop it. (A good sized water bath should work, every 7cm of water halves the radiation and you want hot water anyhow. But concrete is less prone to leak away.) You'd also need to worry about stray neutrons, although I expect that can be fixed with a thin layer of something that has very high thermal neutron cross section and no dangerous daughter products.
In short, I don't think I want this in my basement.
You're right about the tail cone, and your hemisphere plan sounds like it would work. I doubt it would be economically viable. I expect they'd be better off using the older less combustible battery technology than doing all this.
You need to sequester the CO2, else this technology has no point. Possibly the need for suitable geology or the cost of drilling a pipe to the suitable geology might dictate large scale facilities - I don't know. Transportation of coal to the plant might also mean only a few locations with the correct geology are suitable.
Remember that an airliner is a pressure vessel. The maximum pressure differential is on the order of 60 kPa, which is about the pressure of a water column 6m deep. So you want a panel which will absolutely not ever blow out at 60 kPa pressure, but will reliably blow out at (60 kPa + excess pressure caused by fire.) Given that the battery is not in a gas-tight compartment, I can't imagine that excess is very large, even for a significant fire. And all this is without even considering the fact that 60 kPa is the maximum pressure differential, but during significant periods of the flight the difference will be less.
I believe that blow-out panels are already used in the cabin floor so that should one (but not the other) of the hold and cabin suddenly depressurize, the floor will not fail. Such a failure of the floor was part of the chain of causation that caused a near crash and a crash in the DC-10. Wikipedia refers to 'vents' without specifying the type, but I remember reading elsewhere they were blow-out panels. (Although present, they proved inadequate, and improving them was part of the engineering fix made in response to these incidents.)
I download some books as text files from Project Gutenberg, and had a program which would randomly select a ~10 line section from a random file. It would then encode this file as a simple substitution cypher. Finally I had a little program to aid with decoding - it would display the cypher text, and let me try various cypher-letter to plaintext-letter assignments.
I left word spacing and punctuation intact, which makes the problem pretty easy and entertaining. For example, a cypher word 'ABCA" is very likely to be "that" (or otherwise "else" or "says".) If you see words "ABC" and "DBC" they are probably "the" and "she".
Here is the encyphering program. (I couldn't find my original of this, so I've just rewritten it now. I remember the original was a one-liner using all sorts of trickery, but my Perl is too rusty to reproduce that now.) It acts as a pipe - it takes the text to be encyphered on standard input and writes the cypher text to standard output.
#!/usr/bin/perl use strict;
my $plain = join "", map{lc}<STDIN>; my %translate = (); my $nextCodeChar = 'a'; my $cypher = ""; for my $plainChar (split "", $plain) {
if ($plainChar =~/[a-z]/) {
if (!defined($translate{$plainChar})) {
$translate{$plainChar}=$nextCodeChar++;
}
print $translate{$plainChar};
} else {
print $plainChar;
} }
I've managed to find the decoding program, reproduced below. This program is designed to run from a text terminal, and takes the filename of the cyphertext as a command line argument. Automatically extracting the random plain text, encyphering it, and then running the decypherment program on the result is left as an exercise to the programmer.
The EM drive doesn't hypothesize any new science, it claims that our existing science can give this reactionless drive. That is provably wrong, as they've combined a bunch of physics which all conserves momentum and claimed a result which does not conserve momentum.
Just possibly their device might work, due to new physics. But as their explanation is provably wrong, if it did work, it would be a complete fluke. In other words, constructing an EM drive is no more or less likely to demonstrate new physics than any other randomly assembled bit of apparatus.
Nope, GP is right. They accounted for radiation pressure with the paragraph "You CAN make a reaction drive using photons...". But the EM drive doesn't emit photons, so it can't work like this. The comment you criticize is at a much higher level of understanding than yours.
By the logic of the EM drive, a champagne bottle would also accelerate, as it is also a pressurized (approximately) conical volume.
The EM drive claims to mix a bunch of standard physics (Newtonian mechanics, electromagnetism, special relativity) to produce a violation of conservation of momentum. But all of that standard physics conserves momentum. We can immediately know that the claimed result is in error, just as if someone adds a list of even numbers and comes up with an odd total. The error is easy to spot, but we don't even need to spot it to prove that it is wrong.
(The error is pretending that by diluting something you can ignore it - in this case, the radiation pressure component in the direction of the pointy end of the cone.)
I'm going to compare the USA 1,5,10,25,100 system against the very common 1,2,5,10,20,50,100 system (125 system, for short.)
By my calculation (done by hand, so may be a little out) to make all the quantities of change from 0 to 99, the USA system needs 470 coins, the 125 system needs 340 coins. The only quantities for which the USA system needs fewer coins are 25, 26, 35 and 36, for which it is one coin more efficient in each case.
If you took away the 2c coin to have 1,5,10,20,50 (i.e. a 20 and 50 instead of a 25 compared to the USA system) you'd still need only 420 coins (vs 470) for all change from 0 to 99c.
The 125 system works so well because the denominations are nearly equally spaced logarithmically. Starting with 1, you get the next denominations by multiplying by 2, 2.5, 2, 2, 2.5, 2. In the USA system, the multipliers are 5, 2, 2.5, 4. It is those large multipliers (5 and 4) which make the system so inefficient.
If you wanted to span the 1-100 range with just four coins, I believe 1, 3, 10, 30 would be optimal, as it is closest to logarithmic spacing. (Actually, 1,3,10,32 might be better, but that would be a real pain to make change with.) (Even more efficient would be a true logarithmic system: 1,2,4,8,16... or 1,3,9,27,81,... or 1,4,16,64,256... but none of these mesh well with our decimal system.)
On what evidence do you know "THE AMOUNTS MOST COMMONLY NEEDED"? Even accepting your unsupported claim "the very large majority of "change" needed is less than 50 cents", for each amount of change 0 to 49 cents, USA system needs 185 coins vs 145 for the 125 system, so you fail on this count too. If you remove the 2c from 125 and consider only change less than 50c (effectively removing the 50c from the 125 system as we'll never use it, so denominations are 1,5,10,20) then you *finally* get marginally ahead: 185 vs 190. Against this, the 125 system is about one coin better for every number from 50c to 99c, so your 'very large majority' will have to be greater than 90% to even get marginally ahead. (And remember, this is without the 2c, which the 125 system would normally have.)
Are you conflating RTGs and reactors? I associate thermocouples with RTGs, not reactors, and a cursory wikipedia search didn't find any reactors using thermocouples.
RTGs rely on the natural decay of the radioactive fuel, whereas reactors use a chain reaction to accelerate the decay of the fuel. Voyager etc. use RTGs with thermocouples. The device here is an actual reactor, with a control rod and neutron reflector. I'm aware that the U.S.S.R. built reactors for space. Wikipedia lists a few NASA reactor projects, but I'm not sure any of them actually flew. I'm not aware of a reactor being used in an interplanetary probe.
None of us know whether WB have the rights to make the slot machines, whether for casinos or Toys-R-Us, as we haven't read the contracts.
We also don't know that money will soothe the estate's hurt feelings. If the parties settle and the slot machines remain, then it was about the money. If they settle and the machines go, or it goes to trial and the estate insists all along that the machines must go, then it isn't (at least entirely) about the money. It is too soon to rush to judgement on this.
Ngaruahoe, which played Mt Doom for the distant shots, is not erupting. Ruapehu, an adjacent larger vulcano which played Mt Doom in some of the close ups, has recently had its warning levels upgraded. It also is not erupting, but is considered more likely than normal to erupt in the near future. Nearby Tongariro (opposite side of Ngaruahoe from Ruapehu) had a brief minor eruption in August.
I agree - I've often suggested such a game in the past. Part of the reason relativity and quantum mechanics are so hard to learn is they are so counter intuitive. Games like these could train our intuitions.
So each tray gets its time in the sun while going up the tower, and in the shade going down (or vice versa). It seems this would work well only if the plants you are growing are happy getting half the sunlight available at your location. I'm sure you could get a similar effect in horizontal format with little difficulty.
If you can get friction low enough, you might be able to make the whole thing run simply by watering the plants at the top of the down part of the cycle, so the weight differential makes it go.
Scientific American had an article on vertical farms some time back (paywalled here.) As I recall, they had a much more energy intensive design (growing lights etc.) My objection was that for anything like that you could make work in a sky scraper, you could much more cheaply put the same technology out in rural areas.
The Singapore plan only works if there are areas you're happy to cast into shade (and block views from) with these towers. They can't be close together, or they'll be in each other's shade.
Incidentally, Singapore's climate has remarkably little annual variation. The hottest month has average high temperature of 31.7C, the coldest month has average high temperature of 30.0C. Rain is more variable, but still by less than a factor of two through the year. (This is not from personal experience.) If anyone knows of somewhere with less weather variability, I'd be interested to hear of it.
John Banks isn't really necessary for the government. There are 121 seats, National (the main governing party) holds 59, ACT (John Banks) 1. Parties with which National could reasonably do deals to pass legislation (or even negotiate a coalition with) are New Zealand First (8 seats), Maori Party (3 seats), United Future (1 seat.) So they could distance themselves from John Banks and still continue to govern as an effective minority government. The opposition Labour Party effectively lead a minority coalition government in this way for years.
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It can only be female crime fighting goats swinging through the city, as they'll be shooting web from their udders. And then the comic books will get hold of this idea and... .. oh god... ... need brain bleach badly!...
AAAARRGHHH!!
I notice that this did not prevent an uncontained failure of an A380 engine.
OK, so possibly it takes fewer R/C aircraft than geese to take out an engine. Then you wave a magic wand and say maybe the other engine will stop too. Losing one engine does not cause the other to fail, despite your appeal to 'additional stress'. Twin jets are able to fly with one engine. To be certified, they must demonstrate they can safely fly on one engine during the most stressful period of flight (a single engine failure late in the take-off roll.) They can also fly safely for a long time on a single engine. With appropriate safeguards, they are certified to do so for up to three hours (ETOPS-180) and coming soon, for over five hours.
Thanks. Is this why there is so much emphasis on 137Cs in the Fukashima aftermath? Lots of nucleotides must have been released, but media reports only talked about two, and I've been wondering why that was.
Oops, spotted an error. In the paragraph "None of the cross sections are hugely larger than the others..." read 59Ni for 59Co.
For the purpose of this post, I'll accept that they can convert protons to neutrons as described, although I'm very dubious about this.
Here is a table of nickel isotopes.
Here is the first source I found for neutron cross sections of nickel isotopes (pdf). (See figure 12, look at the left hand side of each 'destruction channels for ??Ni' plot for what low energy (thermal) neutrons will do.)
Cross sections are in barns, and are approximate as I'm eyeballing them off a logarithmic scale.
58Ni [stable, 68% abundant] (0.006 barn) -> 59Ni [-> 59Co, 76000 yr half life]
59Ni [unstable but long lived] (0.02b) -> 59Co [stable] or (0.005b) ->56 Fe [stable] or (0.004b) -> 60Ni [stable]
60Ni [stable, 26%] (0.006b) -> 61Ni [stable]
61Ni [stable, 1%] (0.002b) -> 62Ni [stable]
62Ni [stable, 4%] (0.006b) -> 63Ni [->63Cu, 100yr]
63Ni [unstable] (0.001b)-> 64Ni [stable]
64Ni [stable, 1%] (0.004b) -> 65Ni [->65Cu, 2.5 hr]
None of the cross sections are hugely larger than the others, so all these reactions will occur with reasonable frequency. So irradiating nickel with thermal neutrons, you are going to produce radioactive 59Co (76000yr), 63Ni (100yr) and 65Ni (2.5hr). The 65Ni isn't a problem - turn off the reactor, wait a couple of days, and it will all be gone. The 59Co is only a bit of a problem - with such a long half life, it isn't very radioactive. The 63Ni however is nasty. Like 137Cs (30yr) from the Fukashima reactors, the half life is short enough to be quite radioactive but long enough that you can't just wait it out. Finally, the nickel won't be 100% pure, so you have to worry about what neutron irradiation will do to the impurities.
The 65Ni means when you turn off your reactor, it will continue to produce residual heat for hours.
The article gives the impression that weak nuclear reactions aren't dangerous, but this is not so. If it were, nuclear reactor waste wouldn't be dangerous.
This reactor will be producing ionizing radiation when running (mostly gamma rays, some beta rays mostly from 65Ni decay, and a tiny amount of alpha particles from 59Co(n,a)56Fe.) This will require some pretty heavy shielding to stop it. (A good sized water bath should work, every 7cm of water halves the radiation and you want hot water anyhow. But concrete is less prone to leak away.) You'd also need to worry about stray neutrons, although I expect that can be fixed with a thin layer of something that has very high thermal neutron cross section and no dangerous daughter products.
In short, I don't think I want this in my basement.
You're right about the tail cone, and your hemisphere plan sounds like it would work. I doubt it would be economically viable. I expect they'd be better off using the older less combustible battery technology than doing all this.
You need to sequester the CO2, else this technology has no point. Possibly the need for suitable geology or the cost of drilling a pipe to the suitable geology might dictate large scale facilities - I don't know. Transportation of coal to the plant might also mean only a few locations with the correct geology are suitable.
Remember that an airliner is a pressure vessel. The maximum pressure differential is on the order of 60 kPa, which is about the pressure of a water column 6m deep. So you want a panel which will absolutely not ever blow out at 60 kPa pressure, but will reliably blow out at (60 kPa + excess pressure caused by fire.) Given that the battery is not in a gas-tight compartment, I can't imagine that excess is very large, even for a significant fire. And all this is without even considering the fact that 60 kPa is the maximum pressure differential, but during significant periods of the flight the difference will be less.
I believe that blow-out panels are already used in the cabin floor so that should one (but not the other) of the hold and cabin suddenly depressurize, the floor will not fail. Such a failure of the floor was part of the chain of causation that caused a near crash and a crash in the DC-10. Wikipedia refers to 'vents' without specifying the type, but I remember reading elsewhere they were blow-out panels. (Although present, they proved inadequate, and improving them was part of the engineering fix made in response to these incidents.)
Why ask us this? Why not ask them?
Bruce Schneier has pointed out another similar device: http://www.schneier.com/blog/archives/2012/08/200_for_a_fake.html
Here's something I used in that way years ago.
I download some books as text files from Project Gutenberg, and had a program which would randomly select a ~10 line section from a random file. It would then encode this file as a simple substitution cypher. Finally I had a little program to aid with decoding - it would display the cypher text, and let me try various cypher-letter to plaintext-letter assignments.
I left word spacing and punctuation intact, which makes the problem pretty easy and entertaining. For example, a cypher word 'ABCA" is very likely to be "that" (or otherwise "else" or "says".) If you see words "ABC" and "DBC" they are probably "the" and "she".
Here is the encyphering program. (I couldn't find my original of this, so I've just rewritten it now. I remember the original was a one-liner using all sorts of trickery, but my Perl is too rusty to reproduce that now.) It acts as a pipe - it takes the text to be encyphered on standard input and writes the cypher text to standard output.
#!/usr/bin/perl
use strict;
my $plain = join "", map{lc}<STDIN>; /[a-z]/) {
my %translate = ();
my $nextCodeChar = 'a';
my $cypher = "";
for my $plainChar (split "", $plain) {
if ($plainChar =~
if (!defined($translate{$plainChar})) {
$translate{$plainChar}=$nextCodeChar++;
}
print $translate{$plainChar};
} else {
print $plainChar;
}
}
I've managed to find the decoding program, reproduced below. This program is designed to run from a text terminal, and takes the filename of the cyphertext as a command line argument. Automatically extracting the random plain text, encyphering it, and then running the decypherment program on the result is left as an exercise to the programmer.
#!/usr/bin/perl
use strict;
# decypher: aids solving simple substitution cyphers.
# usage: decypher filename
my (%freq, %cypher, %decypher);
# Read the cyphertext
my @cyphertext = map{lc}<>;
# Count the characters
my @copy = @cyphertext;
map{s/[a-z]/$freq{$&}++/ge} @copy;
# To do:
# Print cypher and frequency ordered by plaintext
# one, two, three letter words and frequencies.
# digraph frequencies?
# Loop getting commands /^([a-z])=([a-z ])/i) { guess($1,$2); } /^([a-z])=$/i) { guess($1," "); }
while (defined(chomp(my $command=<STDIN>))) {
if ($command eq "f") { freq_table(); }
elsif ($command eq "p") { plain_text(); }
elsif ($command eq "q") { last; }
elsif ($command eq "c") { clear(); }
elsif ($command =~
elsif ($command =~
else { print
"Unknown command '$command'
Commands are:
'f': print frequency table
'p': print cypher and partial plain text
'q': quit
'c': clear letter associations
<letter1>=<letter2>: associate cypher letter1 with plaintext letter2
<letter>=: remove plaintext association to plaintext letter\n"; }
}
sub freq_table {
my $count = 0;
for (sort keys %freq) {
printf "%s%s %3d %s", $_, $cypher{$_} ? "=$cypher{$_}" : " ", $freq{$_}, (++$count%5 ? "" : "\n");
}
print $count%6 ? "\n\n" : "\n";
}
sub plain_text {
my $tr = "";
foreach ("a".."z") {
The EM drive doesn't hypothesize any new science, it claims that our existing science can give this reactionless drive. That is provably wrong, as they've combined a bunch of physics which all conserves momentum and claimed a result which does not conserve momentum.
Just possibly their device might work, due to new physics. But as their explanation is provably wrong, if it did work, it would be a complete fluke. In other words, constructing an EM drive is no more or less likely to demonstrate new physics than any other randomly assembled bit of apparatus.
Yeah, you should stick to reputable magazines like "New Scientist" instead.
Nope, GP is right. They accounted for radiation pressure with the paragraph "You CAN make a reaction drive using photons...". But the EM drive doesn't emit photons, so it can't work like this. The comment you criticize is at a much higher level of understanding than yours.
By the logic of the EM drive, a champagne bottle would also accelerate, as it is also a pressurized (approximately) conical volume.
The EM drive claims to mix a bunch of standard physics (Newtonian mechanics, electromagnetism, special relativity) to produce a violation of conservation of momentum. But all of that standard physics conserves momentum. We can immediately know that the claimed result is in error, just as if someone adds a list of even numbers and comes up with an odd total. The error is easy to spot, but we don't even need to spot it to prove that it is wrong.
(The error is pretending that by diluting something you can ignore it - in this case, the radiation pressure component in the direction of the pointy end of the cone.)
Sorry, this is complete crap.
I'm going to compare the USA 1,5,10,25,100 system against the very common 1,2,5,10,20,50,100 system (125 system, for short.)
By my calculation (done by hand, so may be a little out) to make all the quantities of change from 0 to 99, the USA system needs 470 coins, the 125 system needs 340 coins. The only quantities for which the USA system needs fewer coins are 25, 26, 35 and 36, for which it is one coin more efficient in each case.
If you took away the 2c coin to have 1,5,10,20,50 (i.e. a 20 and 50 instead of a 25 compared to the USA system) you'd still need only 420 coins (vs 470) for all change from 0 to 99c.
The 125 system works so well because the denominations are nearly equally spaced logarithmically. Starting with 1, you get the next denominations by multiplying by 2, 2.5, 2, 2, 2.5, 2. In the USA system, the multipliers are 5, 2, 2.5, 4. It is those large multipliers (5 and 4) which make the system so inefficient.
If you wanted to span the 1-100 range with just four coins, I believe 1, 3, 10, 30 would be optimal, as it is closest to logarithmic spacing. (Actually, 1,3,10,32 might be better, but that would be a real pain to make change with.) (Even more efficient would be a true logarithmic system: 1,2,4,8,16... or 1,3,9,27,81,... or 1,4,16,64,256... but none of these mesh well with our decimal system.)
On what evidence do you know "THE AMOUNTS MOST COMMONLY NEEDED"? Even accepting your unsupported claim "the very large majority of "change" needed is less than 50 cents", for each amount of change 0 to 49 cents, USA system needs 185 coins vs 145 for the 125 system, so you fail on this count too. If you remove the 2c from 125 and consider only change less than 50c (effectively removing the 50c from the 125 system as we'll never use it, so denominations are 1,5,10,20) then you *finally* get marginally ahead: 185 vs 190. Against this, the 125 system is about one coin better for every number from 50c to 99c, so your 'very large majority' will have to be greater than 90% to even get marginally ahead. (And remember, this is without the 2c, which the 125 system would normally have.)
Are you conflating RTGs and reactors? I associate thermocouples with RTGs, not reactors, and a cursory wikipedia search didn't find any reactors using thermocouples.
RTGs rely on the natural decay of the radioactive fuel, whereas reactors use a chain reaction to accelerate the decay of the fuel. Voyager etc. use RTGs with thermocouples. The device here is an actual reactor, with a control rod and neutron reflector. I'm aware that the U.S.S.R. built reactors for space. Wikipedia lists a few NASA reactor projects, but I'm not sure any of them actually flew. I'm not aware of a reactor being used in an interplanetary probe.
None of us know whether WB have the rights to make the slot machines, whether for casinos or Toys-R-Us, as we haven't read the contracts.
We also don't know that money will soothe the estate's hurt feelings. If the parties settle and the slot machines remain, then it was about the money. If they settle and the machines go, or it goes to trial and the estate insists all along that the machines must go, then it isn't (at least entirely) about the money. It is too soon to rush to judgement on this.
Taking a flippant comment seriously:
Ngaruahoe, which played Mt Doom for the distant shots, is not erupting. Ruapehu, an adjacent larger vulcano which played Mt Doom in some of the close ups, has recently had its warning levels upgraded. It also is not erupting, but is considered more likely than normal to erupt in the near future. Nearby Tongariro (opposite side of Ngaruahoe from Ruapehu) had a brief minor eruption in August.
Don't Warner Brothers have enough money yet without making LotR slot machines?
I agree - I've often suggested such a game in the past. Part of the reason relativity and quantum mechanics are so hard to learn is they are so counter intuitive. Games like these could train our intuitions.
So each tray gets its time in the sun while going up the tower, and in the shade going down (or vice versa). It seems this would work well only if the plants you are growing are happy getting half the sunlight available at your location. I'm sure you could get a similar effect in horizontal format with little difficulty.
If you can get friction low enough, you might be able to make the whole thing run simply by watering the plants at the top of the down part of the cycle, so the weight differential makes it go.
Scientific American had an article on vertical farms some time back (paywalled here.) As I recall, they had a much more energy intensive design (growing lights etc.) My objection was that for anything like that you could make work in a sky scraper, you could much more cheaply put the same technology out in rural areas.
The Singapore plan only works if there are areas you're happy to cast into shade (and block views from) with these towers. They can't be close together, or they'll be in each other's shade.
Incidentally, Singapore's climate has remarkably little annual variation. The hottest month has average high temperature of 31.7C, the coldest month has average high temperature of 30.0C. Rain is more variable, but still by less than a factor of two through the year. (This is not from personal experience.) If anyone knows of somewhere with less weather variability, I'd be interested to hear of it.
They are aware of this. See the footnote to the poster on this page.
John Banks isn't really necessary for the government. There are 121 seats, National (the main governing party) holds 59, ACT (John Banks) 1. Parties with which National could reasonably do deals to pass legislation (or even negotiate a coalition with) are New Zealand First (8 seats), Maori Party (3 seats), United Future (1 seat.) So they could distance themselves from John Banks and still continue to govern as an effective minority government. The opposition Labour Party effectively lead a minority coalition government in this way for years.
OK, it looks like you're correct on that.