Computer History Museum

Yesterday, Urmi and I visited the Computer History Museum in Mountain View, CA. Since Urmi and I are both a bit geeky (me more than her, although she joked on the way there about naming a pet MOSFET), we had more fun than any two young computer scientists are expected to have without the internet. A scant few miles from Google, the Computer History Museum features exhibits covering 2000 years of computing -- although many of the early computers are only now recognized as computing devices (tools such as abacuses, mechanical calculators, Napier's Bones, etc).


The Computer History Museum (CHM) also features a working example of the Babbage Difference Engine No. 2, invented in the 1800s by Charles Babbage and widely recognized as one of the most ambitious computing devices ever designed. Charles Babbage is one of my personal favorite people in history, and seeing the difference engine in action was well worth the price of admission to the museum. The CHM's Difference Engine is one of only two ever built (the other, at the Science Museum in London, is rarely demonstrated), and it is truly an amazing device. The machine computes the value of polynomials using no more power than a human-operated hand-crank. The internal numbers are stored on vertical columns of gears (like below), and percolate from one side to the other as the user cranks the drive shaft.


Once they reach the end, the Babbage engine "prints" them simultaneously onto a reel of paper as well as a tray of plaster, for use in printing tables of numbers. They had configured the machine to produce a 7th degree polynomial (the largest this particular machine can handle), but the machine could easily produce all sorts of different mathematical series. Babbage originally envisioned the machine as a means to produce tables of numbers without any human mistakes -- mathematical tables, such as logarithm tables, were a specialty of his and he particularly hated finding mistakes in his tables. For more details on Charles Babbage or Difference Engine, see Wikipedia.

The rest of the museum was equally amazing, featuring computers from the Apollo Mission, the Bletchley Park Enigma project, and more. Some highlights are below:


An actual wheel from the Colossus Machine, and one of the only remaining intact parts from a functional Colossus. Although the Colossus machine was not a Turing-universal computer, the Colossus machine was integral to the British efforts to break German encryption in World War 2. However, the machine was a groundbreaking effort at the time, and the fact that its design remained classified (and the blueprints destroyed) kept many of its original engineers from being credited with their work on early computers.


Wiring from the Cray 1 super computer. This was the first super computer, built in the mid 1970s by Cray Research, which is to this day a leader in super computing. The machine itself looks a bit like a piece of office furniture from 1970s, but the internal design is a brilliant work of engineering to maximize the speed at which the early computers could operate. This particular machine was used to simulate atomic explosions, meteorological phenomena and more. I'm glad that computers are not built like this anymore.


Joke napkin provided by an early Silicon Valley startup, showing that the get rich quick nature of Silicon Valley has a long history.


Intel goodie given out to employees -- a keychain containing an actual pentium computer processor, albeit one that failed testing.


A "Furby" from the CHM's artificial intelligence and robotics exhibit. A surprising number of the robots on display in the exhibit were children's toys. I'm not sure if I would describe the Furby as particularly intelligent, but I suppose it was no less so than many of the other devices on display.


The Utah Teapot. Aside from the Babbage Engine, this was the display that I found the most exciting. The Utah Teapot is a widely used graphics primitive used to demonstrate different graphics algorithms, mostly since it's a smooth surface, without texture, but with fairly complicated internal geometry. Early computer graphics algorithms had difficulty with the handle and spout of the teapot. Many libraries for graphics contain the teapot as an included object, and there are dozens of in-jokes in the graphics research literature related to teapots with bizarre textures (fur, leopard print, etc). Of particular interest, the widely used GLUT library has a procedure (glutSolidTeapot) that does nothing but make a model of this particular teapot. This is the original teapot that the model was based on.


An early server from Google, circa 1999. Back in 1999 (when I started using Google), this server would have been one of the ones handling user queries.

For more pictures (but less detail), check out my Picasa Web Album.

Castle Rock State Park

View from Goat Rock in Castle Rock State Park
Yesterday, Urmi and I went for a short hike in Castle Rock State Park, located along scenic Skyline Boulevard in the Santa Cruz mountains. We've hiked in this area before (including Russian Ridge, El Corte de Madera, and Pescadero), but Castle Rock was a bit different. For one, the trail we followed took us through dense forest as well as along the edges of cliffs. In several places, we had to climb over rocks and cross small streams, which was fun but a bit more adventurous than we're used to.

Castle Rock State Park is particularly famous for rock climbing, but we had fun with the wildlife here. The migrating birds are just starting to return to the Bay Area, so we saw several Jays, Sparrows, and even a particularly up-close encounter with a hummingbird. We also enjoyed the fresh wildflowers which are just now starting to open up.


Waterfall along the Saratoga Gap Trail


Wildflowers taken near the top of Goat Rock


Small bird taken during our hike


Close-up encounter with a Costa's Hummingbird. This female flew right in front of me and starting eating from a flower I was taking pictures of. One of the luckiest shots I've ever had.


View of Castle Rock Falls from the top of the falls.

More pictures can be found on my Picasa page.

Death Valley

Death Valley from Dante's Point

I've always wanted to see Death Valley, a national park in the Southern US renowned for its lack of water and for nearly killing a group of lost travelers in the 1800s. Today, the park is well visited, particularly in the Spring when the flowers are blooming.

Urmi and I visited the park last week, but we had the misfortune to arrive during a storm with near hurricane force winds, lots of cold weather, and more. We visited many of the major landmarks: Badwater Basin (the lowest place on North America), Devil's Golf Course, and more. Most of the landmarks in Death Valley have similarly ominous names (Furnace Creek, for example, is famous for frequently being among the hottest places in the world), showcasing Death Valley's famous inhospitality. The scenery, though, creates a spectacularly barren landscape of brightly colored rock, salt fields, and other bizarre sights.


Mesquite Sand Dunes, our first stop in Death Valley, are a set of windswept sand dunes several hundred feet high. This picture shows one of the largest dunes, with the eastern Death Valley mountains in the background. This is something of an iconic shot of the sand dunes.


This picture is surreal once you understand the context. In the foreground lies the Badwater Basin salt flats. Badwater Basin is the lowest location in North America, 282 feet below sea level, and is composed of a several inch thick layer of pure salt. In the background is the tallest mountain in Death Valley, Telescope Peak, at 11,043 feet tall. I would suggest that the hikers provide a sense of scale, but they really don't. Telescope Peak is visible from nearly everywhere in Death Valley. Badwater basin is named as such because water from the nearby springs is salt water, and is not drinkable.


One of our stops in Death Valley took us to the aptly named Devil's Golfcourse, a field of razor sharp salt crystals and rock. Like the Badwater Basin, Devil's Golfcourse is mostly composed of salt, but unlike Badwater, the underlying substance is rock (Badwater is mostly fairly soft soil). The fields were named because, according to our guidebook, 'the links are so nasty that only the devil could play golf here'. Sure enough, the links are full of sharp salt crystals (shaped by wind and rain), lots of holes and miles upon miles of difficult terrain.


My personal favorite picture from our death valley trip. When we went to hike in Golden Canyon, we stumbled upon a Boy Scout troop having lunch. I caught this picture of them enjoying a rest after hiking the canyon.


The day we visited Death Valley was cloudy and very windy, so the weather was quite striking. We saw several lenticular clouds (like these) throughout the day. These were taken from Zebrewskie Point.


On our way out of the valley, we decided to make one last stop at Salt Creek to watch the sunset. The sunset from the valley was phenomenal, due to the weather and reflective terrain.

More pictures of Death Valley available on my Picasa Page.

Kent Trail near Alpine Lake

Yesterday, Urmi and I went hiking along the Kent Trail in Marin County. This trail is pretty tricky to find, mainly since it's not really part of any state parks or state recreation areas. You still have to pay to get in, but I'm not entirely sure who you pay to.
Our Kent Trail loop started us between two lakes (Bon Tempe and Alpine), then sent us up a hill through a Redwood Forest. After a grueling mile-long climb up the hill, the forest opened up to give views of the Bay and several Marin county cities. The best part of the hike came when we turned a corner, and I was just getting my camera ready to take a picture of the landscape. All of a sudden I heard a rustle behind me and turned around to see a deer, no less than ten feet away, staring at me as if trying to figure out what the heck I was doing here.

Since I already had my camera ready and everything, I was able to get dozens of shots before the deer lost interest and went away. It kept following us, though, never coming closer than about ten or so feet, for at least a quarter-mile. By far the best (or, at least, the closest) wildlife encounter we've had in California, including the Elephant Seals we saw at Ano Nuevo.
After a mile or so up the hill, our path abruptly changed direction and sent us down a narrow and winding trail through a thick redwood forest. After the sunny and barren hill we had just climbed, the forest was almost like a different trail. We passed waterfalls, ponds and more, before the trail eventually connected with the main loop around Alpine Lake. Apparently the trail is not well maintained, though, as we had reached several areas where whole trees had fallen across the trail. We initially thought we'd made a wrong turn, and had a difficult time getting through the deadfalls.



The hike around Alpine Lake was long and winding, but it was an enjoyable hike. We saw lots of wildlife, including butterflies, birds, and, of course, the deer. I even spotted a Salamander wandering across one of the less traveled parts of the trail. The first half of the trail had next to no one else hiking it, which was nice. Once we rejoined the Kent Trail, however, the trail was much more crowded and full of dogs. Highly recommended to people who can get to Marin County. For more photos, see my picasa album.

Radio Silence

Sorry about the silence here for the past two months. General craziness aside, I just haven't had much interesting to say, nor time to say much. Here's a brief overview of what I've been up to:

• In my continued quest to find interesting ways to present my pictures, I've decided to upload some selected (and often slightly edited) photos to Flickr. I'm not a huge fan of the lossy jpeg compression they use, but the photostream concept is well suited for posting a few photos a day that aren't necessarily related to eachother.
• Played through all of the excellent DS visual novel 9 hours, 9 persons, 9 doors. Lots I could say about this, but my brother beat me to the punch. In short: Best game I've played on the DS, and probably the only game I've played in the last few years that's kept me up to all hours of the night trying to figure out what's going to happen. Comparing this to a typical Hollywood thriller is like comparing Inception to the Disney cartoon of your choice. If you like suspenseful novels (note: even if you don't like games) and own a DS, play this now, if for no other reason than to ensure we Americans get more games like this.

And yeah, that's about all I got. Lots of other stuff going on, but nothing really interesting.

Background Index

My Desktop Background Index is back up to date and now supports the newer 16x9 desktop files I'm uploading. Enjoy.

Bi-weekly Background: 2010.12.03

So I decided to start up my bi-weekly backgrounds again (mostly at the urging of others...) -- they fell off during my trip to India and subsequent chaos. I'll try to be more prompt. For now, though, enjoy this background. It's rather more heavily edited than I've posted in the past, but I think this picture maintains the same flavor as the original while still looking more appealing.

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