Tuesday, July 24, 2012

Honolulu Rail

Another thing that we really liked about Europe and are missing in the US is rail transportation.  It is nice to be able to travel across the country and read a book, take a nap, or get up and walk around at the same time without having to worry about driving.  In fact, this is what allowed us to live for over a year without owning a car.  Also, in general rail is much, much more fuel efficient than driving personal cars (especially when it is one person per hummer on a crowded highway).  When my grandmother was a girl she used railroads to travel, but they have almost completely disappeared now in the US.  We use words like train station so infrequently in American English that these became some of the first words we adopted and used regularly in Germany.  We would say Bahnhof (train station) and Hauptbahnhof (main train station) in the middle of an English sentence.  As fuel becomes more expensive it seems inevitable that we will have to return to--at least some--rail travel.

There is a plan to put in the beginning of a public transportation rail line from Kapolei to Honolulu here in Oahu.  Here is a link to the project's website



Rail has been the hot topic on the radio every since arriving in Hawai'i.  Eventually, some day, it would be wonderful to have a rail system around the island, and it would be nice to use to commute to work, and probably save us a lot of money, instead of driving our van back and forth every day.  However, almost everything I have heard on the radio has been largely negative about the rail project.  In 2008 53% of the island voted in favor of rail (link) but, every since I arrived, people have been trying to get decisions changed and preparations stopped to prevent the rail system.  Now ground has been broken and work has started constructing the line, but the fight goes on and more than one of the people running in the next elections has made stopping rail a major part of their platforms.  Sure, there are things I would change about the rail line, like stops near our house and my job so that we can use it, but a new rail system has to start somewhere.  And, it would be great if it was half the price with no cost overruns, but public transportation is something useful that the government can provide with tax money.  What alternative is there?  This would also give an alternative to people that do not have cars.  Even if the rail doesn't come near our houses we can potentially use buses to connect to it.  Finally, the rail system would benefit all of us whether we used it or not, because of lower traffic congestion and less pollution. 

We were able to sign a house-to-house petition in support of the rail project.  Here are some example links of the discussion in the news: (one) (two) (three) (four)

The Monty Hall Problem

The Monty Hall paradox is a fun problem to think about.  It is named after the "Let's Make a Deal" TV show. 

With a lot of fanfare about prizes, what you do for a living, etc., you are presented with three colorful doors, behind one is a prize, there are no prizes behind the other two (except maybe something like a skunk...).  You pick a door, then the host opens one of the two remaining doors to show you what is behind it--it, of course, is a non-winning door.  There are only two closed doors remaining now, and one of them is a winner.  You are asked if you want to stay with the door you chose or switch to the other door.  You make your decision and the remaining doors are opened to see if you won the prize.  ...cut to commercial...

Ignoring all the stagecraft, in the end you are faced with two doors, one winning and one loosing, so it seems like you have a 50/50 chance of picking the right door.  So either strategy, switching or staying, should be equivalent...

I was playing with Small Basic some more to try to illustrate this.  In the first example the "stay" strategy is illustrated.
The chosen door is colored in yellow, another, non-winning door is opened, then the prize containing door is revealed.

And here is the second, switch, strategy. After you choose a door and the other door is opened you always switch to the remaining unopened door.

After a while you may see that the stay strategy only wins about 1/3 of the time and the switch strategy wins 2/3 of the time.  So you should always switch and the probabilities are not 50/50. 

How can one of three doors have a 2/3 chance of winning...?  It seems like it should be 1/2, or maybe 1/3...?  This puzzle conflicts with our intuitive way of thinking about the problem.  When I first learned about it I told several people that I worked with (at a print shop) about it and they said I was absolutely wrong, that the chances were 50/50 and that I didn't understand statistics... 

This is also an excellent example of a situation where history (data) and prior information matters, which is a cornerstone of modern Bayesian statistics (and here).  If there were only two doors to start with the probability would indeed be 50/50, but the history of arriving at the two doors changes the probabilities.

To make it more intuitive imagine a more extreme situation.  You win an opportunity to participate in a contest at a newly built US Post Office.  There are 1,000 mailboxes along a wall in the building.  In one of them is a check for $1,000,000 and you have to pick which one.  You pick box number 207.  Then all the other boxes are opened to show that they are empty except for box 207, that you chose, and box 853.  Would you stick with box 207, that you chose as one out of 1,000 boxes, or switch to the only remaining box that could possibly contain the check?  In other words, there is probably nothing special about box 207 that you chose haphazardly, but there seems to be something special about box 853 because it was the only other box not opened.

Saturday, July 21, 2012

A rainstorm out at sea


The cycle of seasons in Hawai'i is much more subtle than we are used to.  Still it is there.  For example, there are some trees blooming now that I remember blooming back when I first arrived almost a year ago. We are in a very dry part of the island and in a drought so the grass is light brown and when I water some of the plants the ground is hydrophobic; it is so dry the water beads up on the surface and rolls away instead of soaking in.  Also, there are lots of cactus that grow wild around here.  There are other parts of the island however that get a lot of rain and are the green tropical forests that we associate with Hawai'i and the tropics.  It hasn't rained in a while; from what I am told by the neighbors the summer here is the dry season.  In the fall the rain should return.  Yesterday evening I snapped this photo of sheets of rain pouring from the clouds.  It is out over the ocean and not falling on the island, but it is a harbinger of what should come. 

Plasma Adjustments

The arc of plasma was bending to the wire loop around the base of the neck of our bottle, so I drilled a pair of holes near the base of our vacuum bottle and epoxied a bare copper wire through them to draw the plasma down the full length of the bottle.  I hooked the + end of our rectifier to the base of the bottle and hooked the - to the cap and, via a set of resistors, also to the ring midway.


My hope was the - charge on the ring would help focus the arc toward the center axis of the bottle (of course there are also a lot of + charged ions here so this thinking may be flawed from the get go.  Anyway, in practice it was very finicky.  If the resistance was too low, the arc would just connect from the ring to the base.  If it was too high there would be two arcs, one from the cap to the ring and another from the ring to the base.  In between there was an area where it seemed to work a bit.  However, in this process I kept frying resistors (especially if I made the mistake of shutting off the vacuum before the high voltage transformer to make adjustments). 


Above are some 1/4 watt rated resistors that have been fried by the setup. 


This configuration worked for a while six 1-watt 1,000 ohm resistors coneccted thru two 1/2 watt 1 mega-ohm resistors in parallel.  Until, that is, I forgot and shut down the pump before the transformer, then there was a flash and we lost one of the megaohm resistors. 


Above is the best view to illustrate what is happening.  There is a long arc from the - cap to the + base, but it is deflected to the side near the ring, but under the optimal condition I could find with a - charge also on the ring, it doesn't exactly reach the ring but continues down the bottle.  A secondary smaller arc begins nearby on the ring and joins up with the main current toward the base.


Here is another view where the origin of the secondary arc is more diffuse and spread out along the ring.  All in all, it is kind of doing what I wanted but not really. 

Things to follow up on are placing the mid-ring outside the glass so it can not arc through the vacuum.  Also, a ring of magnets might do the trick.

Friday, July 20, 2012

Small Basic

I was looking around for a C compiler for Microsoft Windows and stumbled across Small Basic (not what I was looking for, but...). In a few minutes I had this « hello world » program running, that can be published online and run from the web.



Try typing into the console above and hitting return.  (The color change doesn't seem to work in the online version.)

Here is the code: 


Microsoft said they made small basic as an easy introduction to programming and to make programming fun.  It is a free download; here is a link if you are curious. 

BASIC was the first programming language I started learning and using, back in the 80s from a book that came with a commodore 64.  In fact I learned to type by programming BASIC.  Typing commands like goto seem automatic, even today.

And, it even has graphics!



And here is a program to calculate prime numbers.  One of the first programs I ever came up with was one like this.




Prime numbers never end in 2, 5 or 0, because we have a base 10 counting system. Once I tired writing a prime number generating program that used base 12, which has many more factors (2, 3, 4, 6) than 10 (2, 5) and could rule out primes based on the final digit rather than trying factors, but it was very inefficient to convert to base 12 and turned out to be slower.

Movie Challenge

The response to my question about an old obscure movie was so fast and accurate, I decided to try a challenge.  What movie is the image from below?  (Someone is firing a flaming arrow.)


Thursday, July 19, 2012

We're not in Germany anymore... Auto mechanics.

My last post about Germany and German culture was quite negative.  So now I am going to post something topical that is an unexpected positive in Germany.  In our experience, auto repair and car mechanics are priced very reasonably, especially in comparison to the US.  You might be paying the equivalent of $9/gallon for fuel, but you don't have to auction off an arm and a leg on ebay to pay to fix the car.

Maybe I am unlucky, who knows, but I have rarely had a good experience with auto mechanics in the US.  In the end I often have to take the matter into my own hands, which costs me time, but usually I do not have the money to spend to pay what auto mechanics demand.  For example, once when we were living in NY we had to replace the windshield wiper motor, I was busy with my job so V took it to a shop.  They took out the motor and then wanted to charge an unbelievable amount of money for the labor.  I absolutely refused.  (Replacing the windshield wiper motor is a very easy, almost trivial, thing to do.)   I went to the shop but they had taken the old motor out, put it somewhere in their shop, and refused to give it back to me to try to force me to pay them to do it.  Instead, I took the car, went to an auto parts store and bought a new wiper motor, then to a junkyard and got an "arm" to connect the motor (for $5) to replace the one they took out.  However, the junkyard lost the acorn nut that fastened to the end just before giving it to me, then couldn't find it, so I had to go to a hardware store to get that...  Then put it in and hooked it up in something like 10 minutes.  I even remember T « helping » turn the socket wrench to attach it (he was very little then).  I could not get the core charge refunded on the old motor because the mechanics refused to give it to me (and I was not comfortable calling the police to get them to return my property because I had not paid them for the initial "labor"), but taking the core charge was still far cheaper than paying them to turn a wrench for a few minutes.  If however, and this is a repeating theme, they had charged a reasonable rate (worthwhile, or possible, for me to pay them versus doing it myself); I would have paid it just to save time and fuss. 

These and other experiences made me very apprehensive about going to a car repair shop in Germany.  However, our car developed a funny oil leak from near the end of a tube next to the engine and we needed to fix it.  We were living in an apartment without any tools, and I have yet to see an auto parts store in Germany like we have in the US.  So we took it in, the guy there was very nice, took a look, replaced a part that cost 8 euros, and that was it.  We asked to make sure, did we need to pay more for labor, etc., and he said it was nothing...!  A total of 8 euros for the ring.  We were both very pleasantly surprised.  Later we took the car back to the same place and each time the repair was very reasonable and hassle free. 

In contrast, we are currently attempting to get a safety inspection to renew the registration on our van here in Hawai'i.  I made the mistake of assuming the auto dealer that I bought the van from had updated the safety inspection, but they had not.  Then a letter from the DMV came in the mail and I was surprised that it cost $340+ for registration renewal.  (Perhaps this is normal in the US; it has been so long I can't remember how much it was each year in NY).  V took it to a shop for inspection and they wanted $1,000+ to approve it!  I do not have this much money available to spend.  They demanded new front tires that had a $500 price tag alone, and wanted to replace the two headlight units (the entire thing because the individual parts are not sold individually) for $100s of dollars, claiming that they were broken and out of spec, plus a few bulbs needed replacing... 

So naturally we refused to pay them for the repairs (we couldn't even if we wanted to).  They gave V a blue form and the woman at the counter clearly said that we give that to the DMV for a 30 day extension to get the repairs made and finish the safety inspection.  If we returned to them the followup inspection was free.  The front two tires were indeed worn.  We replaced the back ones since buying the van and I planned to replace the front ones sometime in the next few months anyway, so we went to Costco and got them replaced for less than $300.  Then we picked up some replacement bulbs for a few dollars and changed out one of the license plate bulbs (that I didn't know existed) and another anonymous bulb on a back light.  That part was ridiculously easy. 

Replacing a bulb on one of the rear light units.

The headlights were claimed to be « broken » because back when I replaced the bulbs there were these funny wire clips that didn't want to go back in, and as far as I could tell didn't do anything important so I left them out.  V's hands are smaller so she popped them back in.  Obviously the entire headlight unit did not need to be replaced. 

So, we made all the repairs for ~$310 instead of the $1,000+ they wanted, and went back in to get the safety approval.  They asked where the receipt was, so we gave them the white piece of paper that had the info from our first safety inspection, but what they actually wanted was the blue form for a receipt.  We told them we sent it to the DMV (I mailed it along with a form from the DMV, asking for a safety form, and a check for the renewal) as we were told.  They said they needed it for the followup inspection and denied saying we should send it to the DMV.  The woman behind the counter, the same one as before, said, oh no, we should have "walked" it into the DMV and showed it to them for the extension, not mailed it to them.  It had the things that needed to be checked on it...(i.e. the "cheat sheet") and they absolutely had to have it for the free followup inspection.  Whatever, we paid another $20 to do the inspection without the blue form they told us to send to the DMV and walked to get something to eat while waiting.  Then, when they were done they had found all these new things that were wrong that they didn't see before.  Two more (tiny front parking) bulbs needed replacing.  I asked why they didn't see it the first time and they said that we must have knocked them loose when we worked on the headlights (implying we should have had them--the professionals--do it, but it was pure nonsense, the bases are not even in contact to be knocked loose..) and, surprise surprise, the headlight units again needed to be replaced.  This time it was because the plastic was too foggy to properly aim the lights for alignment.  But they could do a special "headlight restoration" procedure for us, that was cheaper than replacing the units.  Still this was 100's of dollars.  I asked why the headlights became so foggy between our visits and they didn't have a snappy, lay the blame on us, answer for that one.  I was irritated and let V to finish talking to them while I walked out to the the garage and had the guy show me exactly which bulbs needed replacing now.  Then we took our van and went home.

I picked up a sandpaper adapter for my drill and some fine sandpaper disks and grinding compound, all for just under $20, and using my drill sanded down the headlight covers then polished them to get rid of the foggy plastic layer.  (Why it fogs over so bad I have no idea, the plastic over the bulb next to it stays crystal clear; it makes me suspect this is engineered obsolescence to sell more units over time.)

Before.

Part way thru grinding.  I'm starting to get worried at this point.

Finished product.  Crystal clear!

Then I pick up replacement front parking bulbs, but they don't fit.  I used the computer key at the store for the make, model and year of our van to pick them out, and went back and double checked to make sure, but it gives completely the wrong bulb.  (Later I checked online and other people have reported this as well--for years now.  How hard is it to fix this on a computer system?)  You have to buy these bulbs in pairs (as another way to sell more) so we had an extra bulb from the rear plate light that we replaced.  We popped the plate light right in the socket for the front parking light and it worked.  So we bought another pair (for the one more we needed) and put them in the front parking lights.  (They were burnt out and, by the way, after seeing them on we realized they had never worked since we had the van; not "knocked loose" as the mechanics blamed.)  The right one was easy and took V 5 minutes.  The left one required the intake hose, battery, battery pan, fuse box, and half the air filter be removed to pop it in.  Again, why can't cars be designed better⸮  If there were just a few more inches of room all the extra steps, that are not particularity hard but are irritating (now the clock has to be reset...), would be unnecessary. 

Stuff removed and pushed out of the way to replace a light bulb.

Stuffed back in...

So finally everything is fixed again, except for the headlight alignment, and we take it back, for the third time, for the alignment and safety inspection form.  There are a lot of comments like, we don't know where you took it to get this done...  Implying we should have paid them more to do what we did.  Anyway, it is in the shop and we are waiting nearby when V gets a phone call that the inspection is done.  When we walk back we see that they parked our van in the lane out front, not even in a parking space, ready to drive away, rather than leaving it in the garage or in a parking space as before.  They say we need to get the headlights aligned; we already knew that from the last inspection.  I thought that was what they were doing while we were waiting.  I ask them to please go ahead and do that, align the headlights.  She acts surprised so I try to be polite and ask them to please go ahead and align the lights.  We need to hurry and get the safety inspection done because we are running out of our 30 day extension for registration renewal.  Then the woman says there is no extension for registration, saying "if you're late, you're late" flippantly.  I say that is not what we were told here before.  And she says we are wrong...  So I say, we are new here to Hawai'; can you please explain how this is supposed to work.  (And I am trying my best to be patient and polite.)  She said we do the inspection, you have 30 days to get it fixed, it comes back from the DMV,  we put the stickers on the car, ...  I asked, what comes back from the DMV?  She says, I never said that.  I say, those were your words, you just said it comes back from the DMV.  I just want to be clear so I know what I am supposed to do (is "it" transmitted electronically by them, by mail, do we have to take a form...?).  (This is beginning to feel like the everlasting "missing forms" mystery in Germany.  I wish I carried a tape recorder for these situations.)  She acts flustered, stares at my shirt for a moment, then starts over at the beginning in painful detail, talking to us like we're children.  We check your car, you have fixed what is wrong, then take the yellow form to the DMV, there is no 30 day extension, .... on and on.  Finally we get to the headlight alignment and that it will cost ~$40.  I sign the work order and she takes a copy.  There is another copy still laying on the desk so I ask if it is my copy.  (Not having the right copy cost us $20 at the beginning of this.)  She and the other woman at the desk ignore me entirely; I'm right there in front of them.  Instead they start talking to V about F, is she heavy to carry; blah blah blah, and are making sounds and faces at F.  I ask again if this is my copy pointing at the paper.  Then V picks it up and asks, "is this our copy" and the other woman finally says yes.  ?   There is some weird passive aggression going on.  I ask, can you please tell me how long it might take.  She reluctantly says 40 minutes while looking away from me and the other woman calls out loudly for us to wait there in the waiting room because it is nice and cool with air conditioning (I'm suspecting this is an indirect way for them to say we are not from Hawai'i and work out some passive aggression).  We go out the door to walk around for a while during the wait and are about 20 feet down the sidewalk when a guy comes running out holding, what else, one of the clips from the front headlight.  He says to V (not me) "this just fell out" when they opened it up and it will need to be put back in.  V said, it's easy, you just pop the two ends in beside the bulb and tighten down the screw next to it with the stubby phillips head.  He pauses for a second staring at the clip, because this response from V was not what he planned, then says without eye contact, it will cost an extra $50.  V looks at me and I say that's it; we're going somewhere else.  We take the clip from him, go back in take our keys, and drive off to look for the DMV to get some answers from their side. 

What gets me in this last part is that we tried to pay them to align the lights.  We already paid them $40 for three safety inspections, when it was supposed to cost $20, and were about to pay $40 more for the alignment, but they tried at the last minute to jack that up to $90 so we walked out.  If they had just done what we had agreed on they would have made more money.  ?

We don't know where the DMV is so I drive to the library next to ask the security guard.  The difference between talking to the people at the auto shop and the security guard are like night and day.  He is friendly and polite and gives me the directions.  I thank him and am on my way.  No fuss, no drama. 

At the DMV I try to explain what is going on and show the woman behind the desk the form from the inspection.  (Later, V describes her as unengaged and dreamy.)  At first she is confused and thinks we are shipping a car here from another state.  I tell her no, that I bought it here in Hawai'i, ...  Later, she says all we need to do is get the headlights aligned for the safety check.  We explain that we are trying to get the safety check, with three attempts already, but that each time we go they are finding new things wrong to fix.  She seems to ignore us pointing at the latest safety check form and saying no, it says here you just need to get the lights aligned.  She does not directly answer our question about the non-existent 30 day extension.  She just says that we need to pay an amount for registration that is higher than before (with the late fine added).  I say I already sent them a check and can I have it back first before paying again.  She asks if the check was cashed yet; I say no.  She asks if I have had it returned (hmm...); I say no.  She says, well it was probably just lost in the mail (as if this is a perfectly acceptable excuse).  Anyway, while she was polite, it is clear that not much more clarity will come from the DMV office, so we return home and V puts the headlight clip in, again, and tightens the screw holding it down securely. 

I look up reviews from other people on Yelp for the auto mechanic shop we went to--a national chain.  They are given the lowest possible score and many people described the same problems we had.  So I look up a mechanic in the area with a high review score--not a national chain.  We drive to his shop and I make an appointment for a safety inspection for Friday afternoon.  My fault, I should have done this to begin with. 

To be continued.

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Update:  We went to the new shop this afternoon; locally owned, not the national chain.  Everything was much more professional.  He said it would be ready by 4pm; it was ready at 3:45.  Cost $15 for the inspection, period.  They were very clear and courteous and told us exactly what we have to do next; 1) take the blue form to the DMV to renew the registration, 2) bring it back to them and they put on the new stickers.  Simple, clear.  I know exactly where I am bringing the van next time.  We then drove straight to the DMV but were 5 minutes late.  They closed at 4pm and are not open again until 8am Monday.

-----
Update: Monday morning, we went to the DMV office, showed them the blue form and wrote a check.  They gave me a new registration and a sticker to take back to the inspection station.  (Why can't we just put the stickers on ourselves?)  We drove to the station and they put the stickers on the van and gave us a yellow and pink form.  I asked what they were for and they said the pink one was to keep in the van as proof of inspection and the yellow one was to give back to them when I get it inspected again.  (Who says Germany has more paperwork than the US?) 

Wednesday, July 18, 2012

Trying to find a movie...

I remember a movie that I saw on TV as a kid.  It was possibly made in the 70's.  It wasn't that good of a movie but recently I tired searching for it online and couldn't find anything related, as if it never existed.  So this has piqued my interest as a kind of challenge.

Here is what I remember.  An aeriel photographer takes pictures from a small private plane in a dry scrub country (type of land, not nation) like the US Southwest.  When developing the film in his darkroom it is ruined by red lines in the image.  Later there is an earthquake and he realizes the red lines in his pictures predicted the earthquake.  Then he takes pictures of a small town and the lines are running right thru the town.  So he flies to the town to try to warn everyone and convince them to evacuate...

So, does this ring a bell for anyone out there, what was this movie (title, year, major actors)???

-----

Update: Wow, that was a fast response!  I should have asked here earlier.  So the movie is "The Day the Earth Moved" 1974 starring Jackie Cooper (he played Perry White, the editor of the Daily Planet in the Superman movies), Cleavon Little (Bart in "Blazing Saddles") and Stella Stevens (she was Linda Rogo in "The Poseidon Adventure").  Thanks.

By the way, I used to work in a darkroom like the one in the movie.

Sunday, July 15, 2012

Rhombicosidodecahedron


 
The 62 sided rhombicosidodecahedron has to be my favorite archimedean solid.  At its heart it is a dodecahedron, but the pentagons are separated by squares on their edges and triangles on their corners.  (A step up in complexity from the icosidodecahedron.)  Here we made one, or a close approximation, with 12 equal sized copper rings.  M helped me assemble it and really liked the symmetry.  I also taught T some trigonometry with the angles involved.  This makes a spherical conductive cage!  In the back against the napkin you can see an alumina (aloxite) ceramic tube; it is an excellent insulator and withstands high temperatures and harsh environments well (just try cutting one to a certain length, as I did, and you will see how strong they are).  (You can order them online for a few dollars.)  I ran a bare copper wire connecting to the "rhombi cage" down the ceramic tube. 

Here is a step in assembling it.  We marked 10 points, 36 degrees apart, on each ring where the other rings would cross and made one half, 6 connected rings, at a time before combining the halves. 


I made a smaller, rough, wire sphere to fit inside and also connected it through an alumina tube.  Then wired both of them up on a vacuum stand. I cut out part of a plastic cup and placed it between the wires at the base to suppress occasional arcs between the points where the plastic insulated wire connected to the wire in the alumina tubes. 


We hooked this set up to our 12,000 V DC with the negative in the center and positive around the outside.  Then set a bell jar over the top and pumped it down.  (Note the glass warps the image of the grid within and makes it look squashed but it is still as spherical as it was before.)



We got some nice arcs that danced around the sphere, which in itself is cool, but I was going for a much more diffuse effect and am convinced that the air pressure inside is still too high.  The electrons in the arc are repelling each other and should spread apart, but air, even at low pressures, is a good insulator and once a trail of ionization is established the electrons are forced to channel together along the (temporary and changing) path.  However another effect of air is that the air heats and rises from the arc, so arcs tend to rise, and this did not happen until I stopped the vacuum pump.  What I am going for in this longer-term plasma project with the kids is a Farnsworth-Hirsch Fusor effect where electrons stream out from the center diffusely in every direction.  Along the way they hit gas molecules and knock off more electrons; in turn the positively charged ions fly inward toward the negative core.  The goal is for them to overshoot the inner grid and fly into each other at high velocities near the core.  As I mentioned in an earlier post, 12,000 V can generate very high velocities of particles in a near vacuum.  Potentially high enough to overcome repulsion of the ions due to electric charges and allow them to come close enough together for the strong nuclear force to take over and fuse small nuclei. (Here is a link to the original 1966/68 patent, and here is a different, Hirsch-Meeks, design from 1968/70.)

Lower pressure suggests a stronger vacuum pump.  It's time to break out the big, 0.1 micron physics lab pump I salvaged earlier.

To be continued...

Friday, July 13, 2012

Funny Things F Does

Here are some notes about F over the last few weeks to couple months.

She loves getting out of the house.  Sometimes I take her out with me early in the mornings before leaving to work to water the plants.  When she wants to go out she will bring our sandals over to us and fuss at us to put them on (we don't wear shoes in the house). 

We went into a target and F wanted to get down and walk around.  I set her down and she walked over to a row of clothes.  Then she studiously went down the row stopping at each one, finding the tag and pulling it out and looking at it before moving to the next one.  She can't read and has not idea what the tags are for, but she was doing what she saw other people do.

At the same store she made a beeline for a purse with bright polka dots that are all different colors.  She hung it over her shoulders so it hung down in front of her body.  It went all the way to the floor with her feet sticking out below it.  Then she walked around with her purse.

Every since the ipad she thinks that anything glass with lights behind it is, or might be, a touch screen.  I was holding her looking at a restaurant menu through the glass.  It had a neon sign up behind the glass and she tried enlarging and moving it.  Then later when we went into a store with large TVs all along one wall.  (We don't have TV at home so this was new for her.)  At first they were all blank with a white screen, then colors and a dog appeared all at once along the entire wall.  She was so excited she jumped in place for a moment waving her arms, before getting into forward gear.  Then she ran and pulled herself up on a shelf and was whapping the screen trying to interact with it. 

This last week I was working taking apart and cleaning some equipment.  She was beside me « helping » by touching the end of a wrench to things (but in random positions and without trying to twist it, like the wrench is a magic wand that works by touch). 

She tags along a lot when T goes to his Kung-Fu class.  The school has nick named her "smiley" because she is so happy all the time. 

Also, she's been crawling up into the couch and waving bye to me when I drive to work in the mornings.  And she is happy and excited when she sees me come home, which makes me feel good.





What happens when T watches F for us.  Check out those leg tats!

Thursday, July 12, 2012

Voluntaire

I used to help my paternal grandmother work in my father's garden while I was growing up, especially in the summers.  It was a very large garden by modern standards and we used to produce a lot of food from it.  What we didn't eat she canned and the shelves in the basement would be lined with corn, beans, squash, tomato and other canned foods.  When a plant came up from seed that we did not plant ourselves she called it "voluntaire" and let it grow along with what was planted.  I remember in particular a voluntaire yellow squash and zucchini hybrid (it was a result of cross pollination the summer before) that grew next to some of our onions and its fruits made wonderful fried squash. 

Our landlord had a tree cut down next to our house and all kinds of plants have sprouted from the patch of ground where it used to be heavily shaded.  Including a tomato plant with tiny cherry tomatos and the first word I heard in my mind was "voluntaire" and I left it to grow.  It's funny, I haven't heard that word used in that way for decades, but it was still there in my mind. 



I suspect the tomato is spread by birds eating the small fruits.

This also beings to mind crows and corn.  We had problems with animals eating our seeds.  Moles would go down the row and eat beans we had planted.  Crows would pull up corn as it was sprouting and we would run outside and shoo them off (or shoot at them).  Once I remember a corn plant growing up voluntaire on a hillside far away from our garden.  My grandmother said it was where a crow had dropped it after we ran them away from our garden.

Tuesday, July 10, 2012

Barlaam and Josaphat

Josaphat has been recognized as a christian saint for 1,000 years.  His saint's day in the Roman catholic church is on the 27th of November, the 26th of August in the Greek Orthodox church, and the 19th of November in the Russian Orthodox church.  The story of Barlaam and Josaphat was a popular hagiography in the Middle Ages and was included in the Golden Legend collection of the 13th century. 

Josaphat preaching to his followers. 

The legend of Barlaam and Josaphat has a surprising history.  An English Golden Legend version can be found here (link).  However, it is quite awkward to read.  I am rewriting and simplifying it (with some artistic license) into more modern English and will post it below, then I will discuss the legend some more.  (Note, this does not contain all of the points included in the original version; I have deleted some tangential passages for brevity.) 




Barlaam the Hermit


King Avennir of India persecuted christian men, especially monks. One day, one of the kings friends, Barlaam secretly converted to Christianity and later left the palace to become a monk, which angered the king. The king had him searched out, 'seek him through every desert,' and brought before him. When the king saw him in old clothes and lean from hunger, when he had previously abounded in riches, the king called him a fool and said, “why have you changed your honor into villany?” In response Barlaam said, "if I tell you my reason will you put aside your enemies?" The king demanded to know who his enemies were and Barlaam said anger and craving because they obscure the truth and do not allow one to determine prudence and equity. The king said, “let it be as you say” and Barlaam said “fools despise the way things are, as if the truth did not exist, do not understand what things will becomes, and will not 'use the sweetness of them' and learn the truth of things that are false. Then he showed the king 'many things of the mystery of the incarnation.' The king said, “if I had not promised you at the beginning that I would put away anger from my counsel, I would throw you into a fire. Run away from me so that I never see you again.” So Barlaam left the king with a great burden because he was not made a martyr.

Then a son was born to the king that he named Josaphat. The king assembled a great company of people to sacrifice to his gods for his son's birth and 55 astronomers to predict the son's future. The astronomers said that he would be rich and powerful, but the wisest astronomer said "your son will not remain in your realm but will be in another realm that is much better and he will be of the christian religion." Doubt filled the king when he heard this and he had a palace built away from the city for his son to live in and only staffed it with young people. The king commanded them not to speak of death, or old age, or sickness, or poverty, or anything that may cause a burden. Instead they were to speak to him of joyous things so that he would be filled with gladness and not dwell on the future. And, if any of the servants became sick, they were to immediately be taken away and replaced.

As the king's son grew older he began to wonder why his father had secluded him. He demanded that one of the servants tell him why he was raised this way and said that he had become very sad to be locked away. When the servant told this to Josaphat's father, the king was full of sorrow and arranged horses and joyful fellowship to accompany, and protect, him for travel out of the palace. However, Josaphat met a leper and a blind man. He was shocked and asked his servants what was wrong with them. They said that this is suffering that comes to people. He asked if these sorrows come to all people and they said no. Then he asked if it is known which men will suffer in this way and they said no one can know what will happen in their future. This knowledge created anguish for Josaphat. Another time he found an old man without cheer, that had lost his teeth, and was bent with age. Again he asked what had happened to this man and was told him that he had lived a long time. Josaphat asked what would come in the end and he was told about death and that it came to all people. Then he asked, “after how many years does death come?” and was told in 80 or 100 years. Josaphat dwelled on these things and it caused him a great deal of worry, but he pretended to be glad in order to continue learning about the world.

Even though Barlaam lived in the desert of Sennar he learned about what had become of the king's son. Barlaam dressed as a merchant and traveled to the palace. He told the palace guard's that he had a precious stone to sell that restores sight to blind men, speech to the dumb, and wisdom to fools. The chief guard told him to first show them the stone and prove that it had these powers, then he could see the king's son. Barlaam said the stone was only for Josaphat and demanded that he be taken to him. The guards spoke with Josaphat and he saw Barlaam at once and showed him in with great honor. Barlaam said to Josaphat, “you have done well, for you did not take heed of my smallness and appearance but you acted like the king who met with poor men and sprang out of his chair to the poor men's feet and then embraced them. Then the king's barons spoke of how the king had acted shamefully and insulted his own majesty. The king heard of this and took four chests and had two of them covered in gold and filled them with filth and bones. Then he had the other two chests covered in pitch and filled them with precious gem stones. Then he called in his barons and asked them which of the chests were the most precious, and the barons replied that the chests guilt in gold were of the greatest value, so the king opened them and a great stench came out. Then he closed them and opened the chests covered in pitch to reveal that they contained gems. The king said, “these chests are like the poor men I met and honored, they wear rags yet they are full of virtue, but you barons do not consider what is within when you judge.”

Then Barlaam taught Josaphat about the creation of the world, of the day of judgment, the rewards of good and evil and the folly of worshiping idols. As an example he told a story about a hunter that captured a little bird and when he was about to kill the bird it said: “Why would it help you to kill me? I am too small for a meal, but if you let me go I will teach you three wisdoms that will profit you greatly if you keep them.” In surprise the hunter agreed. Then the bird said: "Never try to take things you cannot have. Do not sorrow for lost things that cannot be recovered. Do not believe in things that are impossible. If you follow this advice you will do well.” So he let the bird go as he had promised. Then the bird flew up into the air laughing at him and said: “Ha! Wretched man. You have lost a great treasure today! I have swallowed a precious jewel that is now in my stomach and is larger than an ostrich egg!” Then the hunter was angry and tried to capture the bird again by saying: “Come to my house and I will show you all the human's secrets, and give you anything you might need, and afterward I'll let you go honorably.” Then the bird said: “Now I know you are a fool because you have not learned from the knowledge I gave you. You are sad to have lost me when I can not be recaptured. You are trying to take me when you can not fly after me. Furthermore, you believe I contain a precious stone that is larger than my body.” Likewise fools trust in idols, because they worship that which they have created themselves.

Then Barlaam began to discuss the fallacies of the world and the delights and vanities thereof. As another example he said: “People desire corporal delights and their souls die of hunger. It is like a man that, because he is running from a unicorn, he falls into a pit and, while falling, catches hold of a branch part way down; however, two mice, one white and the other black, are gnawing on the root of the tree. He sees a horrible dragon at the bottom of the pit casting fire, and the dragon is ready to devour him. The heads of four serpents emerge from the sides of the pit. The man then lifts his eyes and spies a little honey in the boughs of the tree; he forgets the peril he is in and focuses entirely on the sweetness of the drops of honey. The unicorn is death that always pursues man. The pit is the world full of wickedness. The tree is the life of man and the mice are time that eats away at the tree. The four serpents are the four elements that corrupt the body. The dragon is hell, which desires to devour all creatures. The honey in the boughs of the tree is the false sweetness of the world, which deceives man so that he takes no heed of the peril he is in.

Then Barlaam baptized the king's son and returned to the desert. After many years Josaphat spent two years wandering the desert searching for Barlaam. At last he found a cave in the earth and said “father bless me” at the door. Barlaam heard his voice, went out and embraced him. Josaphat dwelled there for many years in penance and when Barlaam had finished his days he rested in peace about the year of our Lord four hundred and eighty. Josaphat left his realm at the age of 25 and led the life of a hermit for 35 years full of virtues. He was buried by the body of Barlaam. When the king Barachius heard of this, he came unto the place with a great company. God has shown many miracles at the tomb of these two men.

-----

Parts of this legend will be eerily familiar to many readers.  One of the steps in the path that led me to stumble upon this legend is the following picture by the 17th century Friesland copper engraver Bolswert (ca.1585-1633). 


The similarity to the allegory of the pit in the forest told to Dhritarashtra by Vidura in the Mahabharata (link) jumped out at me when I saw this.  (I actually happened to mention this allegory in a blog post back in January when our van broke down.  I prefer to see it differently, when life is full of frustration and intractable worry what should you do⸮; reach out and taste the honey with elan.)  Yet the engraving is from Europe and several details were different so I looked up more about what it was based on.  Here are some other versions that were cast in terms of a man in a tree being gnawed by mice with the beasts all below.  The next one is from a 15th century Yorkshire manuscript in the British Library, London. 


And this one is from the Speculum Maius, the compilation of all the knowledge of the European Middle Ages. 


Above, Barlaam the monk is speaking to prince Josaphat about the pit allegory.  Apparently, an element of Hindu religion made it from a 4th century BC Sanskrit epic to a Medieval European christian legend--in remarkable detail, right down to the black and white mice.  But this is not the only remarkable part of this legend.  You may have already noticed something else in the story.

This has touched on two of the modern world's major religions, Christianity and Hinduism.  Let's include another one.  According to tradition, Siddhartha Gautama Buddha who founded Buddhism, was the son of an Indian king.  He had a naming ceremony on the fifth day after his birth and eight Brahmins were invited to tell his future.  They all said he would either be a great king or a great spiritual leader; however one of the men also said that he would become a Buddha.  His father tried to shield Siddhartha from from human suffering as he was being raised in a palace.  At the age of 29 he left the palace and came across an old man. His charioteer explained to him that all men grew old.  Then he came upon a sick man, a corpse, ... which depressed him.  So one night he snuck away from the palace to become an ascetic and learn how to overcome human suffering...  I am glossing over many details but the similarity between the life of Buddha and the life of Josaphat should be obvious.  One of Buddha's teachers was even a hermit named Alara Kalama, which, when you say it out loud, bears some sound similarity to Barlaam. By the way, while Buddha was working toward enlightenment he was sometimes called a Bodhisattva, a wise-being. 

Speaking of names, Josaphat can be Iosaphat in Latin, which was Ioasaph in Greek in the 11th century, and Iodasaph in Georgian in the 10th century.  Before entering Europe the story was copied from an 8th century Arabic text where Budhasaf became Yudasaf from an error in transcription.  (The initial b, بـ , is similar to an initial y, يـ , with only an extra dot.)  Budhasaf was Bodisav in earlier Persian version of the story, which is obviously from the Sanskrit Bodhisattva.  (link)

So not only did a Hindu allegory make it into Christian legends of the Middle Ages; Buddhism had an influence in the same legend, and Buddha himself was even venerated as a Saint.

Monday, July 9, 2012

Perception and Inattentional Blindness

First, before reading any further, see if you can correctly count the number of times people wearing white shirts pass the ball. 



By now I'm sure almost everyone has already heard of this.  However, about half of the people that are not familiar with this will miss something « obvious ».  We simply can't process everything around us so we have to learn to pick and choose what we pay attention to.  This is something I've thought off and on about for a long time in different ways, and I thought I would start off posting about it with this striking example.

The wikipedia page on perceptual blindness has plenty of examples of missing something in plain sight. 

When I was a kid I used to like to play capture the flag.  There were obvious ways to hide like wearing camouflage and staying behind objects.  One time however I was crossing a stream and walking up the bank on the other side, it had lots of sticky mud and medium-large round stones to navigate over on the bank.  I realized that I had been looking straight down at my feet to keep my balance and avoid twisting my ankle or getting stuck in the mud and would have missed anyone hiding off to the side; so I hid off to the side and it worked like a charm.  Later people asked how I managed to appear right beside them.  I used this, objects or situations drawing people attention away--people tend to look at certain points in certain directions--many times after that in various ways (it's easy to do, just keep a mental map of where your attention is directed and hide in the blank spots--in fact I have purposely tried to break these habits in order to notice new things).  However, I also wonder if another layer of misdirection could be added so that, if something drew away enough of a persons cognitive attention (like talking on a cell phone and not realizing you're driving like a moron), perhaps they wouldn't notice you, or something, even if you, or an object, were obvious and in plain sight. 

Sunday, July 8, 2012

A high voltage full wave rectifier

Earlier I posted about building a full wave rectifier from an LED diode bridge to use with our foxhole radio.  The transformer we've been playing with is alternating current, which means the electrons in our partial vacuum are first accelerated in one direction, then reversed and accelerated in the other direction many times a second.  To live up to their full potential what we really need is direct current.  However, normal diodes won't work, the voltage will easily spark across them.  So I got a hold of four microwave diodes (W10163432) designed for handling high voltage.  Also, I didn't want circuitry with this much power laying around bare on a table top, so we planned to embed them in paraffin wax (pure paraffin wax is a better insulator than almost anything except some types of plastic) in an old brie container (M likes to snack on brie).  Perhaps this is overkill, but it also has the benefit of making the bridge rectifier a single portable unit. 


Above, gathering materials and diagramming our strategy. 

First we needed to set up a double boiler to melt the paraffin.  I was planning to use two of V's pots but she forbade me from getting melted wax all over her new soup pot, so I picked up a stack of recycled aluminum trays for a couple dollars and used them as our crucible to melt the wax. 


We punched holes and ran some copper wire through for handles to lift the crucibles out of the boiling water.  If you try this, do not use a single wire across the middle for a handle (like the one on the left).  We tested this with water first and it tilts to one side and dumps whatever is in it.  A much better arrangement is to have three connections like the one in the middle, this gives much more control and allows the contents to be tilted and poured out. 


Above, a block of paraffin is completely melted. 


M pouring wax into the base of the brie container. 

Then we soldered the diodes together with wires to access each corner of the bridge.  It was a horrible soldering job, the thick (AWG 12) wire and large diodes sunk all the heat away from our cheap soldering iron repeatedly giving cold joints and having to retry; it was ugly in the end with solder blobs but the circuit worked.  (Pay attention to the cathode stripes on the diodes.  They have to run from one corner to the other.) 


We mashed the circuit down part way into the first layer of wax while it was still warm and started melting the second block of paraffin to pour over it. 




Above, the now transparent upper layer of wax is setting over the diode circuit.  Below is with the lid added and holes punched for the wires.  The circuit takes AC at two of its corners and converts it to DC at the other two corners.  Later I marked the + and - ends so I wouldn't forget. 


It was a hot day, while we waited for the wax to set the kids went outside to play and cool off for a while. 


Then we hooked it up and tried it out.  The most obvious difference was the DC plasma beam was much more responsive to a magnetic field (on the end of the screwdriver). 


The path near the magnet is bent toward a curve perpendicular to the magnetic field from the magnet. 




I was curious if we could detect any bremsstrahlung (braking radiation) from the setup.  This is seen with high voltage particles that undergo changes in acceleration (like running into the wire or glass on the sides).  The change causes the electron (or ion) to shed energy in the form of a photon, like the light emitted when electrons are captured by positive ions in the tube, but the photon can be even higher in energy than visible light, in the ionizing X-ray range. Long story short, we got some very spurious results. 


I placed our homemade geiger counter on a remaining piece of the shoepad (that we used to insulate the quad gyros from vibrations) because the vacuum pump was vibrating the table top.  In this position you can see a reading of over 20,000 counts per minute, or 165 µSv/hr!  30 minutes of this is about the dose received by people living within 16 km of Three Mile Island during its nuclear accident, but it would take about 3 hours to equal the exposure of a mammogram.  Fortunately however, this is a completely false reading.  The electric field caused the counter to go haywire, some times it would read zero for long periods of time, once symbols went all over the screen and I had to re-upload the program, and at other time it gave transiently high spike readings like this. 


Above is a plot of the recorded counts per minute on a log scale.  Counts around 10 are normal background levels around here.  Counts above 100 and long stretches of zero are not normal and presumably complete artifacts.

A challenge from the kids

After the last gumdrop tower challenge T and M told me to build my own tower if I thought I could do a better job (in response to my suggesting they work more triangles into the structure).

I tired to think about how to reduce the weight up top but make it sturdy lower down to prevent the structure from buckling.  Again I was limited to an 8 1/2" base.  At first I tried a dense core of two tetrahedon stacks superimposed on each other (rotatred 180 degrees) with a wide base.



Then I stacked a less dense, light weight, frame over this base and extending much higher.


I like the patterns it makes when you look through these kinds of structures. 

 
However, it wasn't completely stable and the « head » slumped to the side and fell off a few hours later leaving the height at 18". 


So I tried a different strategy.  Warren trusses are very stable in one plane.  So I tried coming up with a three-dimensional generalization of a warren truss.  This is certainly possible but not easy to do when the edges are all the same length (toothpicks) and the vertices (gumdrops) must come at the ends of the toothpicks.  In other words tetrahedrons don't stack in a straight line. 


Above are some examples I used to try to visually think through this.  In the lower center is a tetrahedron.  To the left is a icosahedron that arises from packing tetrahedrons together.  To the right is a warren truss in two planes, but they result in weaker square links to each other along the remaining edge. 

Then I thought about the fact that, given the same weight and material, hollow tubes are stronger than solid rods.  (If you drilled half of the volume out of the center of a rod to make a hollow tube you loose half the weight but not half the strength.)  So I tried wrapping a warren truss around in a cylinder and stacking the cylinders.  It quickly became apparent however that I needed to brace each layer from the center to prevent the cylinder from deforming.  I did this with a single chain of gumdrop toothpicks that do not provide any support in vertical planes, only in the horizontal plane. 



This approach gave a nice dual spiral pattern around the outside of the cylinder.  I managed to build it to a stable height of 16", which was only 2" lower than my previous attempt but it used a lot less material (and also the gum drops had been reused several times and were about to fall apart anyway).  Perhaps a combination of the two approaches would work even better, a dense core at the base and a « warren tube » extending up from that?