Diverging Diamond

I read a neat article recently at work about a graduate student who came up with a new way of laying out a highway interchange. The problem with interchanges is the traffic that has to turn left to get onto ramps or the crossroad. Left turns make for conflict points for possible accidents and make traffic signals less efficient because only 1/4 of the traffic gets to move at one time. Also, since left-turning traffic backs up into traffic going straight, you put them in dedicated storage lanes. So a 4-lane road might have 4 through lanes and 2 left-turn lanes on the bridge adding expensive bridge square footage (about $100 per square foot). So what this guy did was said why not put an intersection at each end of the cross-road that shifts traffic to opposite sides of the road so that people actually drive on the wrong side of the road over the bridge? If you are on the left side of the road already, it is easy to turn left onto the ramp. And people coming off of the ramp who would be making a left could also make an easy left (if they are turning right they merge in on the other side of the intersection so it still works like an easy right). Anyway, this is called “diverging diamond” interchange as opposed to a regular old diamond interchange. The nice thing about it is that existing interchanges can be retrofitted to a diverging diamond. Another advantage is that by eliminating the need for left turn lanes, the bridge only has to carry two-way traffic, so it saves on the width of the bridge or lets you increase capacity of the interchange without widening the bridge and buying up the gas stations and restaurants that always show up on the corners.

After touting the interchange for several years with research spent on analyzing the design through traffic simulations, they found out that France already had a couple of these. But the first one in the US was just opened last year in Missouri and Georgia plans on doing several as well. You can click on the picture below for a bigger version. Notice from the crosswalks that pedestrians walk down the middle of the bridge.

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Another similar concept, only without driving on the wrong side of the road, is a tear drop interchange where you put traffic circles (they are actually squished into tear drop shapes) on each end of the interchange. Here is an aerial view of one in Colorado. With traffic circles there are no left turns, everyone makes right turns. Another approach is to make the whole interchange a giant traffic circle: at the north end of the circle a bridge carries westbound traffic and the bridge on the south end carries eastbound traffic. You would need two (narrower) bridges this way but still avoid building left-turn lanes. Here is an aerial view of one in New York.

Ultrafire WF-502B with XP-G R5 LED

Overall Rating: ****

Ultrafire WF-502B with 1-mode Cree XP-G R5

Summary:

Battery: 18650/2xCR123A
Switch: Reverse clicky
Modes: 1
LED Type: Cree XP-G R5
Lens: Glass
Tailstands: No
Price Payed: $17.24
From: DealExtreme

Pros:

  • Bright
  • Cheap
  • Good battery life
  • Looks good

Cons:

  • Rough threads
  • Not much heatsinking

Continue reading “Ultrafire WF-502B with XP-G R5 LED”

Praise You (Like I Should)

I remember watching some kind of MTV or VH1 compendium of best videos and seeing one I really liked for Fat Boy Slim’s song “Praise You”. It’s a pretty famous video, but probably a lot of people still have never seen it or even heard of Fat Boy Slim, who was in the 80’s British band The Housemartins under his real name, before mixing electronic music as a DJ calling himself Fat Boy Slim (and using an Amiga computer, no less, at least up through doing the music for the movie Moulin Rouge in 2001). I put the song on Grant’s MP3 player and he says it is one of his favorites.

Anyway, I was writing a review of the movie Where the Wild Things Are which I had very high hopes for since I always thought it was a cool children’s book and it has Spike Jonze directing. He also directed one of my favorite movies, Being John Malkovich and starred in a lesser favorite, Three Kings. Well, Wild Things didn’t turn out that great, but I looked up the movie on Wikipedia and wound up reading more about Spike Jonze. He got his start making commercials and music videos, which I knew. One of the videos he made, well into his career (after a number of videos and around the time of Malkovich), was for Praise You. And what I did not realize was that the main guy in Praise You is Spike Jonze himself as a nerdy community-oriented B Boy dancer. The video itself looks like something someone would shoot and put on YouTube, but at the time there wasn’t quite so much material out there like this. But it was certainly shot the same way, and when the manager of the theater comes out to turn their boom box off, that is real, since they didn’t get permission beforehand.

You can watch the video on YouTube and read more about the song on Wikipedia

Mom’s New Laptop

Mom dropped off her new Dell Inspiron 1545 for me to set up this weekend. Her old laptop was a Frys store brand, but this is a Dell and the price was the same (except that she got an extended warranty on the first one and this one she is just doubling Dell’s one-year warranty with her credit card). Moore’s law says that the number of transistors on a computer processor doubles every two years. It has been five years so everything should be at least 4 times better and maybe 6 times. Let’s see:

The old processor was a 1.3GHz Celeron and this is 2.2GHz Dual Core Pentium. Since there are two cores (processors) now I’m going to say this qualifies, but I have no idea how many transistors are on a Celeron or a Pentium. She had 256MB RAM and now she is getting 3 GB of RAM (1 GB was added to the old laptop later on). So that is 12 times. The old hard drive is 40 GB, the new one is 250 GB (6 times).

There are some notable changes between laptops of yore and today. Most of the ports, including the USB ports, were on the back of the old computer. Now they are on the sides. Her laptop didn’t come with a built-in wireless card (though the computer that replaced it when her hinge cracked did) but it was 802.11g and this one is also 802.11g (I guess that’s more of a notable lack of change). In the meantime they have come out with 802.11n, and most of the higher end laptops support that, but this one does not. There is a SD card reader in the front for transferring pictures from a digital camera. Also, while the old laptop had a microphone, this one has a microphone and a web cam for internet video calls. Also this screen is wider in relation to the height to mimic HDTV’s. That changes the overall shape of the laptop a little, but this one seems about the same size and maybe a pound lighter than the old one (and noticeably lighter than my 2-year old Dell), which was pretty heavy. Lastly, this computer has Windows 7 and the old one had Windows XP, so she skipped right over Vista. I like Windows 7 so far. It seems pretty snappy and hasn’t given me a ton of warning messages.

Many Mini Daffodils

I planted a bag of mixed daffodils several years ago in the little plot in front of my house. It gets a lot of sun and the daffodils come back every year. The regular ones come up first and are followed a week or two later by these little multi-daffodils where several smaller flowers are on a single stalk. So all of the regular flowers have died back and all of these little ones have just bloomed. Time for the macro lens.

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