The coming age of calm technology

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Mark Weiser and John Brown of Xerox PARC wrote this article in October 1996 about a new approach to technology they dub "calm technology".

The article starts off with an introduction to the four phases of computing: mainframe, PC, internet/distributed, and ubiquitous computing (UC). If you're not familiar, UC is the idea that computers will become so prevalent, they will disappear into the background just like electricity has. The authors summarize it like this: The UC era will have lots of computers sharing us.

But the interesting parts are their ideas on "calm technology" and their ideas on periphery and center:

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JavaWorld article on polymorphism

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"Reveal the magic behind subtype polymorphism" is a decent article on polymorphism.

It talks about the four types of polymorphism: coercion, overloading, parametric, and inclusion (sub-type). Most OO developers are comfortable and familiar with the first two. Since the article is java focused, it can't really give example of parametric polymorphism (templates in C++), but it still talks about the principals of this type of polymorphism.

The last type for polymorphism, inclusion, s the one that is the least understood. In fact, it's the one that I always ask about when interviewing an OO programmer.

How much information is there in the world?

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Maichael Lesk speculates in this 1997 article:

How much information is there in the world? This paper makes various estimates and compares the answers with the estimates of disk and tape sales, and size of all human memory. There may be a few thousand petabytes of information all told; and the production of tape and disk will reach that level by the year 2000. So in only a few years:

  • we will be able save everything — no information will have to be thrown out
  • the typical piece of information will never be looked at by a human being.

Later in the article, he estimates that the average human being can store (remember) around 200 MB of data.

The reason that non-elective group insurance is cheaper

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At most of the companies that I've worked for, they have a deal on life insurance that is very inexpensive, but with one catch — you have to sign-up for the life insurance before your first day of work (more or less), or else you have to jump through some hoops if you later want to get the insurance. It turns out there's a reason why, as described by Daniel A. Graifer (dgraifer@cais.com) in the 15 Apr 2001 Crypto-Gram newsletter:

… the other big bugaboo of insurance: "adverse selection": Insurance buyers have better knowledge of their risk characteristics than the insurers, leading higher risk clients to over-insure (because it's cheap relative to the risks) and low risk clients to under-insure. That's why non-elective group insurance is cheaper than individual policies in any risk category.

telespree handset

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telespree is making a very basic cellular phone that doesn't even have a keypad. Just an on/off button. When you turn it on it, you're connected to an automated voice-activated system. You say something like "dial 5 5 5 1 2 1 2" to dial a phone number.

I wonder how well it works if you're in a noisy environment? What if you don't want people around you to know the phone number of the friend you're dialing?

The system is designed to be essentially disposable so that they can be sold from vending machines, convenience stores, etc.

Fun with the5k.org contest

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Here are some of the entries that I played around with that I thought were interesting/cool. BTW, some of these are very picky about the browser…

Magical Bit-Recycling Tool
Man, this one chews up the CPU, but kind of cool effects. Just don't type too fast.

PixxxelChix – A 5K Porn Site
Hysterically funny. Just like the real thing (so I'm told)

cn y rd this? lrn bt ntrpy!
Very impressive (and informative) use of compression. Read the page, then be sure to 'view source'.

e-cology
Although the author challenges you to find a stable system, I think it's more fun to see how wildly you can make things swing. I could never drive either the rabbits or the foxes to extinction, but I could get them to completely disappear, with an occasional huge but brief explosion. (thanks to one of the commenters for the suggestion of de-stabilizing the system).

tableGenetics
Lets you play God/Nature and direct the evolution of html tables.

Flipmaze
You got to be patient on this one, but it's fascinating to play. Get your marble (blue) through the ever-changing maze to the exit (green) before the bad guy (red) gets ya! Just hover your mouse over the green arrows below the maze to move.

Rubik's Droid
Imagine being inside a rubik's cube. Think of this as the three-dimensional Minatour's cave. Even though you have a perfect string (it tells you where you are and which way you're facing) you'll still get completely lost. Even worse, you're supposed to push these balls around. Did I mention that the maze is "only" 10x10x10? :-)

Categoriesfun

Visual acuity

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I've read somewhere that with good vision you can resolve features on the scale of 500 arc seconds (0.1 degrees), or around 1/8 inch at 10 feet. But this is only true at the center of your field of view.

Then there's the issue of how fast your acuity drops off from the center of your field of view. Last October, Skip forwarded this to me, from a paper at www.acm.org

Visual acuity is the ability of the eye to resolve detail. The retina of eye can only focus on a very small portion of a computer screen, or anything for that matter, at any one time (Wickens 1992). This is because, at a distance greater than 2.5 degrees from the point of fixation, visual acuity decreases by half. Therefore, a circle of radius 2.5 degrees around the point of fixation is what the user can see clearly. In the GUI world, this is the Rule of 1.7 (Sarna 1994). At a normal viewing distance of 19 inches, 5 degrees translates into about 1.7 inches. Assuming a standard screen format, 1.7 inches is an area about 14 characters wide and about 7 lines high (Helander 1988). This is the amount of information that a user can take in at any one time, and it limits the effective size of icons, menus, dialogs boxes, etc. If users must constantly move their eyes across the screen to clearly focus, the GUI design is causing a lot of unnecessary and tiring eye movement.

According to studies cited by Jakob Nielsen, 300 dots-per-inch at typical reading distances may be a magic number for resolution — this is the resolution at which people can read as fast as reading old-fashioned typeset documents.