25 September 2006

Innovations in Pavement

I must admit, I don't really pay a lot of attention to the surface beneath my feet unless I'm roller-skating (which I do rarely, and poorly). But I read about some nifty pavement-related inventions, and I have a new-found respect.

The first idea that caught my attention is the use of titanium dioxide as a coating for pavement and roof tiles. Titanium dioxide is sensitive to light, and in the presence of light and water vapor, turns nitrogen oxide (one of the emissions that causes smog) into harmless vapors. Pavement with titanium dioxide has been in use for several years in Japan and is now being tested in England and Italy.

Another interesting pavement innovation: porous pavement. Pervious Pavement is a type of concrete that has the same capacity as regular pavement material but can drain water at a rate of 8-12 gallons per square foot per minute. This eliminates the needs for storm drains, minimizes the risk of flooding in urban areas, and helps to prevent erosion.

New kinds of concrete are made from recycled materials, which is always a good thing. Sulfur concrete is made from sulfur (a byproduct of refining petroleum) and coal ash (a byproduct of, um, burning coal). Other types of concrete being studied are made from blast furnace slag, sludge from paper mills, agricultural waste such as rice husks, used rubber tires, and recycled soda bottles.

22 September 2006

Airplane Boarding Procedure

How many times have you gotten stuck in the aisle or the jetway while waiting to board a plane, thinking "there must be a better way to do this"? Sometime in the last few years, I was traveling an airline that was participating in an experiment to test a boarding procedure called Wilma (boarding Window first, then Middle, then Aisle). I don't remember feeling that the boarding process went any more smoothly than usual, but I was relieved to think that someone was putting some thought into these things.

Turns out, people have put lots of thought into this very issue. I found an article that analyzes current boarding procedures using Lorentzian geometry and computer simulations. I didn't dedicate a lot of energy to understanding all the math, but I do remember that Lorentz is typically associated with chaos theory, and the general theme of chaos theory is that some systems have too many variables and are too dynamic to be predicted, let alone tamed.

So it seems with airplane boarding. Even if the back-to-front system were perfectly implemented so people were ordered by individual row, rather than by sections of rows, people would still be waiting in the aisles. This is because the rows are spaced closer together than one row's worth of passengers - row 38 can't board quickly because row 39 passengers block row 38, and they are standing in the aisle while row 40 is boarding.

One of the factors which delay boarding is that people who are seated in aisle seats get up and block the aisle to allow window and middle seat passengers to get to their seats. Wilma would eliminate this problem, if implemented well. Evidence from airlines, however, suggests that the Wilma fails because of our own resistance to being regulated by boarding procedures at all. Wilma also becomes less efficient when people with window seats arrive at the gate after boarding has begun. Shuttle by United tried to adopt Wilma ten years ago, but abandoned the attempt because of passengers' reactions.

Another factor in boarding delay is aisles being blocked by people trying to stow luggage in overhead bins. With new security regulations limiting what passengers can bring in carry-on, it is possible that more luggage is being checked, and as a result there is less delay caused by stowage problems. All the articles I found agree that enforcing carry-on luggage restrictions is one way airlines can improve boarding procedures.

Other procedures have been tried: Southwest's solution is to abandon assigned seating altogether, essentially creating a totally random boarding process which seems generally acceptable to passengers. Passengers are likely to be positively influenced about their experience if they are given more sense of control. AirTran implemented a new system last year, which boards the back four rows, then the front four rows, working towards the middle of the plane. It seems this system would work well, provided people with rear seats who arrive late are held until the next wave of rear-seat boarding.

Keith Devlin points out that airlines are also making decisions based on customer satisfaction, which means that certain passengers will always be given preferential boarding, whether or not science supports this practice.

15 September 2006

Motorcycle, Art and Illusion

This work, Lunch With a Helmut On, was created in 1987 by the sculptor Shigeo Fukuda. It is made entirely from knives, forks and spoons welded together.

11 September 2006

Crop Circles and Geometry Lessons

So, it’s been done before, but I was going to write a bit about crop circles – I spent the weekend sick in bed and indulged in two television shows about them. When I started looking online, I got bogged down in all the theories; I’m not going to recount them here – there’s so many – but I found a website that really spins my top. Zef Damen has created a site with step-by-step recipes for making many of the crop circles that have appeared in the last decade. (He also has instructions for making a working clock out of Legos.)

Damen has not included my very favorite crop circle design, but I found a very helpful report to get me started on my own recipe. This crop circle appeared in West Stowell, Wiltshire County UK on 14-15 July 2000. It was 280 feet in diameter.

Not so much my inclination, but Andrew Glassner has created an algorithmic language for making crop circle-like designs, and has tested them out using a pressure washer in parking lots.

When I get back to teaching, my geometry students are going to get a photo of a crop circle, a compass and straightedge, and an hour to write a game plan. Then we’ll head for the soccer field!

(For the record: I think some crop circles are human-made, but some are not. I believe that even the experts can't really tell the difference, except for obvious hoaxes. I don't believe in aliens, UFOs, or the channeling of psychic energy. I tend to lean towards the electro-magnetic/plasma vortex family of theories. And I hope this mystery gets figured out in my lifetime!)

06 September 2006

Dorm Life and Suicide

I've worked as a psychiatric social worker and a counselor in a city whose culture is dominated by the local university. One of my most wrenching cases was that of a student who killed himself by jumping off a ninth floor balcony. Suicide is unfortunately common among college students; figures suggest that suicides occur at a rate of three per day on college campuses.

I've been horrified to read over the last few weeks about cases of universities enforcing policies to evict or suspend students who are seeking treatment for depression and suicidal behavior. Fortunately, it seems that these policies aren't holding up against the civil rights of the students:

Hunter College
A female student attempted to take her life by ODing on Tylenol, then called 911. Upon her release from the hospital, she discovered that she had been locked out of her dorm room. She was allowed to collect her things while escorted by a security guard. Hunter's policy was that a student who attempted to commit suicide could not live in campus housing and was required to take a full semester off. The student's lawsuit agains the university was based on Fair Housing Act, the ADA, and Section 504 of the Rehabilitation Act. She received a monetary settlement and the college dropped its suicide policy, which had been in effect for three years.

Allegheny College
A student with a 2-3 year history of depression and suicidal ideation hanged himself in an off-campus fraternity house in 2002. He had been actively involved in treatment, including medication, counseling with university clinicians, and a brief hospitalization. He refused hospitalization several times. His parents sued Allegheny and the clinicians who worked with their son, citing the school's failure to act on clear signs that he was an immediate danger to himself. The school's legal defense involves the student's right to privacy and the Family Educational Rights and Privacy Act, which limits the medical information universities may share about their students. The case was settled in favor of Allegheny in 2005.

MIT has the unfortunate reputation of having an elevated suicide rate compared to other colleges and universities. In the last few years, the school has settled two cases out of court. In one case, a student died in a fire in her dorm room, after expressing thoughts of killing herself that day to two other students. It is not clear whether the fire was an accident or an act of self-immolation. In a second case, a student drank cyanide and died in 2001. It appears that her suicide was due in part to the stress of being stalked by a male student, and her parents brought suit against MIT based on their inadequate handling of the stalker. As part of the settlement, MIT expanded their mental health services and provided training for non-clinical staff.

George Washington University
The most heavy-handed case I researched is that of a student at George Washington University, who sought emergency treatment for depression after the suicide of a friend. While hospitalized, he received written communication from the university stating that he had violated the school's code of conduct, was suspended, was evicted from his dorm. He was threatened with arrest if he returned to campus. He is using Fair Housing Act, ADA, Rehabilitation Act, and the DC Human Rights Act to sue the university for discrimination. It appears that the case is still unresolved, and the student is completing his education at another school.

Clinicians have expressed concern that mandatory leave policies will discourage students from seeking support for depression and suicidal ideation. Colleges and universities are working with people who are in a difficult gray area, clinicially speaking. College students are typically 18-22, grappling with many of the issues of adolescence while legally adults. College is also a transition period for families, since students are living away from home for the first time and taking on more responsibility while parents are adjusting to being less involved in the day-to-day lives of their children.

More on this from Inside Higher Education

02 September 2006

The Root of Root Beer

Inspired by a recent trip to In-n-Out Burger, I started wondering: what roots are used to make root beer? My guess at the time was sarsaparilla, and in part I was right. A little research reveals that root beer has been made from a wide variety of plants, including (not just roots, but also berries and herbs from) sassafras, sarsaparilla, vanilla, juniper, wintergreen, cherry tree bark, birch bark, licorice, anise, cinnamon, dandelion, ginger, yucca, and a bunch of other things I can't spell. The recipe we have come to know and love was invented and marketed by a pharmacist, Charles Hires, in the 1860's. The beverage gained popularity after he introduced it (as a powdered drink mix) at the 1876 Philadelphia Centennial exposition. He and his family began selling bottled root beer in the 1890's.

Although root beer is usually associated with North America, the British have experimented with root teas since the 18th century, starting with colonial American recipes. Alcoholic versions of fermented root beer were brewed, though non-alcoholic recipes were far more common and gained especial popularity during the temperance movements of Britain and the United States.

In 1960, the FDA banned the use of sassafras because of emerging research suggesting that safrole, the oil of the sassafras plant, is mildly carcinogenic. Sassafras bark was banned in 1976. The root beer industry probably would have died without the advances in chemistry to allow for the creation of artificial sassafras flavors. Modern recipes for root beer use artificial flavorings, or use young sassafras shoots, bark, and leaves, which do not contain safrole. Safrole can also be extracted from sassafras root so the root can be used safely.

In 2005, a Canadian high school student researched the medicinal potential of sarsaparilla, another key ingredient in traditional root beer, and determined that it may have great potential as a cancer-fighting medicine. Sarsaparilla grows wild and abundant in certain parts of Saskatchewan.

(An aside about In-n-Out Burger: after reading Fast Food Nation five years ago, I quit fast food entirely, with In-n-Out Burger being the sole exception that didn't totally gross me out by the end of the book. If you are lucky enough to live near an In-n-Out Burger, make sure you go armed with the secret menu.)