Optical Flow Switching

Chan, Weichenberg, and Medard Optical Flow Switching. A proposed communications protocol, but one which has some insights for transportation (if not immediate applicability)

Motivated by the minimization of network management and switch complexity in the network core, flows are serviced as indivisible entities. That is, data cells comprising a flow traverse the network contiguously in time, along the same wavelength channel, and along the same spatial network path. This is in contrast to packet switched networks, where transactions are broken up into constituent cells, and these cells are switched and routed through the network independently. Note that in OFS networks, unlike packet switched networks, all queuing of data occurs at the end users, thereby obviating the need for buffering in the network core. Core nodes are thus equipped with bufferless optical cross-connects (OXCs). OFS is a centralized transport architecture in that coordination is required for logical topology reconfiguration. However, OFS traffic in the core will likely be efficiently aggregated and sufficiently intense to warrant a quasi-static logical topology that changes on coarse time scales. Hence, the centralized management and control required for OFS is not expected to be onerous. The network management and control carried out on finer time-scales will be distributed in nature in that only the relevant ingress and egress access networks will need to communicate.

(emphasis added)
So instead of storing and buffering (on-road queueing), they allocate the whole path between origin and destination to the flow (a trip).
Of course, since this is communications, there are some things they can do that transportation cannot:

If any errors are detected, a request for retransmission of the whole file is done via feedback to the transmitter.

(Sorry, your trip didn’t work out, please have your clone repeat the trip).

Intercity Bus: Jefferson Lines

Strib has an article on Jefferson Lines, a local Intercity Bus company: Jefferson Lines: Flying low

Traffic on daily roundtrips has risen from 16 passengers a day between Duluth and Minneapolis when Jefferson took over from Greyhound in 2004 to about 90 a day. And that’s before Jefferson added two more express routes last week.

Compare with the proposed so-called High Speed Rail (110mph) Northern Lights Express which will cost at least $615 M (and probably closer to $1B) to build, serving the same market.

The American Bus Association Foundation commissioned a study by DePaul University Prof. Joseph Schwieterman that found that motorcoaches are the most fuel-efficient transportation mode. They provide, on average, 207 passenger miles per gallon, compared with 27 miles per gallon for single-occupant automobiles, 44 miles per gallon for airlines and 92 miles per gallon for commuter railroads, based on typical passenger loads.
What’s more, the airlines need something more than 80 percent of seats full to make money. [Jefferson Lines] needs fewer than half the seats filled on a 55-passenger coach to make a profit.

So the NLX will travel 155 miles in 2 hours (averaging 77 MPH), while buses, which are slightly slower (we could say they should be able to average 60 MPH on this route, which is almost entirely interstate), but more fuel efficient. So the difference is 0.58 hours. Is 17 MPH for 2 hours (i.e. 34 minutes savings for 90 people a day worth a $1B capital investment and a higher environmental cost? 90 people * 34 minutes/person * 365 days/year * 30 years = 33 507 000 person minutes saved. (or $30/minute or $1800/hour). That is a high value of time required to justify this HSR line over its most similar alternative, commuter bus. (I.e. car is not the right comparison, since most people are going point to point, not station to station, and will need transportation on the other end. People going to/from Duluth to the MSP airport to change planes, will probably still want to fly rather than transfer in downtown Minneapolis at significantly extra time)
(This back of the envelope analysis ignores discounting (which makes the value of time higher) and induced demand (which makes the value of time smaller))
OK, so bus is not marketed the way HSR would be, and HSR might attract more passengers. But surely this problem is solvable for significantly less cost than the capital required to construct a new HSR line.

Nice Ride Minnesota launches

Nice Ride Minnesota launched recently, it is a bike sharing program for Minneapolis. Some photos of one of their campus, and their Dinkytown site are below. They seem to have more bikes than Zipcar has cars, which befits our position as one of the best cities for biking. I even saw someone using it. The user interface looks quite good, if we could only get this level of investment for buses.









Tales Of Two Cities: Love Thy Neighbor

From the Howard County, Maryland blog Tales Of Two Cities: Love Thy Neighbor
An almost perfect example of how to respond to pure free-riding problems, establish exclusion. Phase 1 paid for a road through their neighborhood which connects to a future Phase 2 development. Phase 2 comes along, and cannot come to terms with Phase 1 about paying for this local road (owned by a homeowners association, apparently, and thus is fenced out.

A few weeks ago I received an email from a Tales of Two Cities reader about a turf war going on between the residents of the Legacy at Ellicott Mills Phase 1 and Phase 2. The conflict between the two active adult communities has escalated to the point where the Phase 1 residents have now gated off their community from Phase 2, denying Phase 2 residents direct access to Route 104.

There is a fair solution to this problem.

Standardization and Coordination Externalities

A typical remote control for Cable TV in the first part of the 21st century has up and down arrows to adjust channels. Pushing the up (plus) button will move you away from channel 0, while the down button will move you toward channel 0 (although if you reach the final channel, you will return to home). But remote controls also have a navigation for the onscreen guide. this has an up, down, left, and right arrow. The up arrow moves you through the onscreen guide, but here up move you toward channel 0, while down moves you away from 0. The left and right arrows move you forward or backward through time.
These remote controls have a further set of controls to operate an auxiliary device like a DVD or an inbuilt device like a personal video recorder. The left arrow, following the convention from tape recorders, plays (forward in time), while the double left arrow (on the right-most side) is fast forward and the double right-pointing arrow (on the left side) moves you in reverse (rewind). Other buttons do other things.

Image of Telephone Keypad: 1, 2, 3 increasing from top to bottom, with 0 at bottom.

Image of Calculator Keypad: 0, 1, 2, 3 increasing from bottom to top.

Complaints about the complexity of modern remote controls are hardly unique (Nielson, J. (2004), ‘Remote Control Anarchy‘.) . Each remote is custom for a particular box, so as people accumulate boxes attached to TVs, the number of remotes increases accordingly. The utopia of the universal remote remains unreached; one hopes the situation will not sustain for another few decades before standardization moves in, or some other interface becomes widespread.


Like remote controls, keypads are another area where conventions may confuse.
Keypads on telephones and calculators represent the same ten digits, however they have different layouts. The telephone keypad, introduced with the advent of Touch Tone dialing by the Bell System in the 1960s places the number ‘0’ (or letter ‘O’ for operator, it is not always clear on telephones) at the bottom, and then numbers digits 1 – 9 in three rows of three columns each from the top. A calculator keypad (also used on computer keyboards) on the other hand, while it places 0 at the bottom, numbers 1 to 9 also in three rows of three columns, but in this case beginning at the bottom, as shown in the Figure. These conventions have carried over to computers, which could array numbers in any random way, but use the different conventions to represent the different devices. Newer devices, such as television remote controls, could use either, but typically follow the telephone layout (though some have original layouts themselves, e.g. going from 1 to 4 on the first row, 5 to 8 on the second row, and 9 and 0 on the third row).
For operating a television, rarely an urgent activity, the additional cognitive load of a poorly-designed or non-standard interface is annoying, but not dangerous. With the case of election ballots, such confusion and resulting error may change the outcomes (such as the odd butterfly ballot used in West Palm Beach, Florida in the 2000 Presidential election, resulting in a disproportionate (compared to other jurisdictions) number of votes for Pat Buchanan, and likely giving the state of Florida, and thus the United States electoral college and the presidency to George W. Bush).
American travelers trying to write emails in some European countries may note that the standard QWERTY keyboard found in the English speaking world (so-named for the keys on the top-row of letters) has been replaced by a keyboard, which mainly swaps the Y and Z, but has some minor changes, dubbed the QWERTZ kezboard. This is just enough to throw off touch-tzpists (er, typists). I am sure the confusion is two-way.
For driving cars in the United States, many functions have been fortunately standardized. The brake foot pedal is on the left, the accelerator on the right. The steering wheel itself usually performs as expected. Less critical functions remain confusing, especially when switching cars, or driving an unfamiliar vehicle, such as a rental car, the difficulty compounds as this is usually done in an unfamiliar place. Where is the windshield wiper? The light switch? The brights? The transmission control? The radio? The environmental controls? The locks? The window controls? The rear-view window control? The unlock for the trunk? The unlock for the gas tank? Where is the gas tank – driver or passenger side? All vary with make, model, and year of vehicle.
Driving on the left of the right is standardized locally, but not globally. As any traveler from continental Europe, North America, or South America knows, things differ on the islands of Great Britain, New Zealand, Japan, the Caribbean, and even the island-continent of Australia.
Traffic signals usually report red on top and green on bottom. What does it mean when the light is simultaneously red and green? Or red and yellow (amber), or green and yellow? Or the green light flashes? All of these patterns are local, but not global standards.
Standards are pervasive (imagine if each car required a different gas nozzle at a gas station (beyond the obvious differentiation for leaded and unleaded). But what in the world could be standardized and produce coordination externalities, but just has not been because the institutions for such organization have not yet been established?

The Elevator Button Problem


John Graham-Cumming: The Elevator Button Problem

User interface design is hard. It’s hard because people perceive apparently simple things very differently. For example, take a look at this interface to an elevator:
Now imagine the following situation. You are on the third floor of this building and you wish to go to the tenth. The elevator is on the fifth floor and there’s an indicator that tells you where it is. Which button do you press?
Most people probably say: “press up” since they want to go up. Not long ago I watched someone do the opposite and questioned them about their behavior. They said: “well the elevator is on the fifth floor and I am on the third, so I want it to come down to me”.

Traffic lights for the color blind

From Autoblog Uni-signal Traffic light with shapes for the color blind.
The principle seems right, the symbols seem wrong. Red should be an octagon, to align with the stop sign. If we use LEDs we could actually spell out the word “stop” (though this might have trouble in winter). An idea worth playing with.