Interesting read about what we have known all along about passwords.

In a lot of ways, the results shouldn’t surprise anyone, given what we know about the operation of human memory: if you give users a task that’s nearly impossible, they won’t do it.

A Stick Figure Guide to the Advanced Encryption Standard (AES)

I’ve started using Lightning for my calendar and I really like it except for the stupid balloon tips that pop up and get stuck every time my mouse passes over the Thunderbird window, even when it is below another window. I turned them off with Edit->Preferences->Advanced Tab->Config Editor… and setting browser.chrome.toolbar_tips to false. Much better now.

The iPhone and iPod Touch are very interesting platforms for enabling technology. Touch, accelerometers, portability, radio, coolness; they’ve got it all.

But the rules of program distribution are so ridiculous that I can’t imagine playing by them. I want to give my apps away. And I want to do it without some faceless technician’s approval.

After you’ve done the work to develop your App they can reject it without giving any reason.

This recent post from Riverturn illustrates the problem though I’ve heard of many more cases like this.

I’m thinking of things we can do with the nearly ready Wiimote (and Balance Board) capability in our Outfox extension. We can use the accelerometers, IR camera, buttons, and rumble. I’m going to list game/activity ideas so I can recruit some help.

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I’ve been concerned about the humidity in my crawl space since we moved in. In fact, I wondered about it at our former house but never did anything about it. At the current house we’ve had some problems with water getting under the house in heavy rains but I think I’ve got that whipped.

I decided the first step was measuring the humidity under there so I bought a Honeywell TM005X Wireless Thermo-Hygrometer and put the remote unit under the house. I bought it back in January 2009 and boy was I shocked. The humidity seldom got below 75% even in the winter! As the summer came on and the humidity rose to above 90% I decided I had to do something. It is so humid down there that water condenses on the cold water pipes and drips on the floor.

Completing the plastic covering on the floor (about 20% was uncovered) did nothing. So I went looking for solutions. I found the SmartVent Crawl Space ventilator and after reading their convincing argument that you can’t dry under your house with wet air, I decided to purchase one of their vents. It cost me $315.

It arrived less than 1 week after I ordered it and I installed it the next weekend. I had never removed a crawl space vent before but it turned out to be a pretty easy job. Mine were installed with mortar which I broke out using a long chisel and a hammer. It took me approximately 1/2 hour to prepare the opening to receive the smart vent. The place I chose to install it had an electrical outlet nearby so I was set for power. I used clear caulk to seal around the opening.

I installed it on 20 June 2009. After 2 weeks my crawl space humidity is down to 77% from 92% on the day I installed it. I’ll make a table below to record occasional readings. It has been dry here since I installed it. That, no doubt, is part of the rapid improvement but since I’m not doing any sort of controlled experiment, I’m just going to report what I see.

The SmartVent appears to be well made and runs a clever algorithm. It has two muffin fans, a small circuit card, and a thermometer and humidistat positioned near the front grill. It uses these sensors with the fans off to sample the outside air. If the outside air temperature is above 42 degrees F, it runs one fan for about 15 minutes to pull crawl space air over the temperature and humidity sensor. It then compares the dew point of the outside air with the dew point of the crawl space air. If the dew point outside is lower both fans run to pull wetter crawl space air out so that it will be replaced (through leakage) by dryer outside air. If the outside air is wetter than the inside air, the unit waits.

My sporadic observation of its habits confirm that it is behaving as expected. I’ve seen it running continuously for the last few days while the outside dew point has been low but last week it ran much less because the outside air was very humid.

I’ll try to record some readings here so I can track how it does.

Note: On 14 July 2009 my Honeywell wireless hygrometer died and I replace it with an Oregon Scientific RMR500A. The calibration was clearly different. I calibrated the new one using the damp salt method.

I expect it to become gradually harder for the SmartVent to improve the situation under the house because as it lowers the dew point, there will be fewer times when the outside dew point is lower. But, I hope and expect it to be better than it was.

I’m thinking about the client-side interface to our Big Words project with the Center for Literacy and Disability Studies. Rebecca is making good progress on the server-side logic for the games, the instructive feedback machinery that is the essence of this approach. But we need a good looking user interface to keep kids coming back.

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Karen suggests it might be useful to develop VR scenarios to help kids become accustomed to normally stressful audio over stimulation without the added social burden of having to deal with people at the same time. For example, many kids can’t go to the movie theater because the THX sound thing at the beginning overwhelms them. If they could experience that THX sound in a controlled environment with gradually increasing volume it might not be so bad when it happened at the theater.

Lots of other situations could be handled similarly.

Another neat idea from Karen. There have been some news stories about a DVD that helps kids with autism learn to read faces and emotions. It would be cool to do a version which allows folks to upload their own pictures and which presents the faces in an interactive web site.

Karen says many kids in wheelchairs never get to experience typical theme park rides. What can we do about that?

We could build or buy a platform that can tilt (say) 20 degrees in two directions under computer control. I don’t think it has to be very high performance at all. We roll the kid’s chair onto the platform and strap it down.

John suggests a platform with a center pivot, springs on 2 sides and stepper motors with cables on the other 2 sides. Missy says we should ask Disney who have all this figured out.

A group of our students go out to a theme park (or the state fair) and record wide-angle HD video, acceleration and good audio. Then we synchronize playback on a big screen (or screens). Perhaps a sub woofer adds some low frequency shake (or maybe the platform could do this). I don’t think we need any “wash out” algorithm for the motion platform. Simply, display the best approximation to the direction of the gravity vector that the tilt platform can manage. We might want to rotate the image to undo some of the tilt. That would be an interesting study on its own.

The log flume ride would be perfect for this. We could spray the rider with some water at the end!

Then we can invite kids in for a virtual carnival or theme park field trip. That would be a ton of fun and an exciting project. Later groups of students could do fully computer generated graphics and sound as more advanced projects.

John suggests we could record historic train rides and such for more educational content.

We link to Tar Heel Reader by having kids read about the experience beforehand and write about it afterward!

I’m going to try to resist immediately jumping on this until I find some $ to pay for it.