Thursday, December 24, 2009
Wednesday, December 23, 2009
Tuesday, December 22, 2009
Friday, December 18, 2009
Wheel Truing Part Ib
The first step in truing a wheel is to bend the crap out of a nice straight one with some hard riding like that done by Mr. Dan Ennis in the clip below. This video comes to us courtesy of Mr. Goodbike and features Dan, a friend of the Goodbike, ripping it up somewhere in North Carolina. Hell yeah!
Monday, December 14, 2009
Wheel Truing Part Ia
Sunday, December 13, 2009
Wheel Truing Part I
*begin transmission*
The most widely viewed wheel truing video on youtube sucks. Maybe that's a bit harsh, but there are several things that Bikeman fails to explain or do properly that will really cause problems for the very people - who apparently number 75,740 - that need to watch that kind of video. The staff here at Casa Pepperoncini in association with the Facebook group "People 100% Against Deedle Dumpling" are working hard to address this deficiency. A full color video entitled "Wheel Truing Part II" is currently in production and will air soon on this channel. Please adjust your crystal sets accordingly.
*end transmission*
Thursday, December 10, 2009
Another Take on "ClimateGate"
A main reason that I am a proponent of bicycle commuting is my belief that bicycles can be a key part of reducing pollution that comes from automobiles. Transportation emissions account for a significant percentage of global emission of pollutants. The complex brew spewing from tailpipes includes hydrocarbons, nitrogen oxides, particulates, carbon monoxide, and carbon dioxide. This last molecule has been implicated as the cause of anthropogenic global climate change more commonly known as global warming. Or has it? Some people have seized on the recent illegal release of emails between climate researchers, claiming that the emails demonstrate a conspiracy in which the evidence for global warming has been fabricated. Which brings us to the point of this post. I am not an expert in climate change. I haven't downloaded and plowed through all 120 MB of the released emails. I can however provide the viewpoint of working scientist, and that is the following: I am mostly unconcerned about ClimateGate. There are several reasons for this. Although it is true that some of us are irrevocably scarred from the memory of that pretty girl in 5th grade homeroom who laughed at me when asked to the dance and that some of those people will go on to build orbiting instruments of Armageddon, most of us are good eggheads. But there are perhaps more compelling reasons for my attitude. Some of what I have seen in the popular press has been extremely misleading. Important points have been missed.
1) Claims of data manipulation: I hear ClimateGate commentators derisively referring to data manipulation as if that by itself is somehow wrong. The fact is that virtually all raw data needs to be manipulated in order to make sense of it. A slew of software exists for just this purpose. Data are smoothed, differentiated, filtered, and thoroughly mathematically churned. Data are discarded because of perfectly legitimate statistical reasons or because you realize that your fluximizer was not properly thermalated for the first 10 minutes of your experiment. And so on.
2) Citations of researchers using "tricks" to "hide" results: As has already been pointed out, it is not uncommon in Geekville to refer to a clever way of solving a problem as a "trick". Similarly, the word "hide" is frequently used in the context of displaying multiple items that overlap. Igor Pro is a common data manipulation software package. A search for the word "hide" in the Igor manual shows that the word turns up more than 150 times. One "trick" that I have used to "hide" something (an axis) in an Igor graph is to change its color to that of the graph background, thereby rendering it invisible. Nothing nefarious there, I assure you.
3) Scientists are people. People are self-serving. Therefore, scientists are self-serving: One of the easiest ways to make a name for yourself in science is to overturn an existing paradigm. The contrario spirit runs deep in our blood and has been an essential part of the scientific mindset since well before Galileo's time. Just ask my wife. To a young climatologist early in his or her career and with not a lot to lose, the juiciest of all the low hanging fruit would be to show that humans are not responsible for global warming. But this has not yet happened.
It may yet turn out that some climatologists have faked or improperly treated their results. But there is no conspiracy. The "climate-change-denialist fringe" referred to in the previous link imperil us all.
Monday, December 7, 2009
The Moth Light
Ever since our slightly ditsy friend Adelheidi mistook my skylight for an actual electrical fixture, she's been hearing about it. The skylight was full of dead miller moths, and Adelheidi had told me to make sure I turned off "the moth light". I looked at her and said, "You mean, the Sun"? Since then, when Kelly and I are outside and it's really hot, it's not uncommon to hear somebody complaining about The Moth Light being turned up too high. We find that we get the most bang for our buck out of references to The Moth Light when Adelheidi is within earshot. Anyway, the point here is that The Moth Light is powerful. On a clear day you have about 1000 watts per square meter of Moth Light bearing down on you. It is a testament to the efficiency of the bicycle that it is entirely possible that some day, just the sunlight hitting your body could provide the power to scoot around on two wheels. Skeptical? An in-shape cyclist might produce a few hundred watts of power for a short length of time. Let's assume that us normal folks produce about half of that, about 150 watts. If we take the area of the typical human shadow to be 0.7 square meters, then we have about 700 watts of light hitting you and your clothing on a clear day. How much of that light energy might we capture, and how? Some of my fellow geeks are actually working on integrating thin film photovoltaics with clothing and other textile products. Let's assume they are successful. The current world record efficiency for thin film photovoltaics stands at right around 20%. Putting those numbers together yields an estimate of 140 watts of harvestable photovoltaic power, a level very comparable to the energy cost of cycling. Now, I am of the opinion that most of us would benefit and even enjoy generating that power ourselves. Nevertheless, for the elderly, disabled, or dressed up among us, a sun-powered electric scooter would be useful at times. And it is sobering to contrast the idea of the sun scooter with the reality of the energy hog we know as the automobile. Even the new old Prius that Kelly and I scored a couple weeks ago needs to produce about 80,000 watts to push us around town. I find it satisfying that the humble bicycle, an invention over 100 years old, competes so well with something as modern and high tech as a hybrid automobile.
Saturday, December 5, 2009
More lighting
There have been several great Globe posts about lighting (see e.g. Jon, Matt's on BikeHacks, Brenda's, and the articles about the awesome MonkeyLectric lights on Totcycle and BikeHacks). I have not seen mention of these lights that the Rev. Dr. Teton Harry recently clued me into and that I just ordered for my Haul. The Reelights are batteryless, magnetic induction powered LED-based flashers. Some models have a small capacitor that stores enough juice to keep you visible while stopped at traffic signals. While their claim of "no resistance" seems to be in violation of the First Law of Thermodynamics, I do believe that their simplicity and lack of mechanical resistance gives them an advantage in both efficiency and reliability over typical generator systems. The Rev. Dr. Teton Harry and Swedish Christine sing the praises of these lights for their night journeys across Stockholm, and trust me, we need to listen to these people more.
Knee update: I'm off the crutches and am using a Bledsoe Brace for walking across snow and ice. A full rotation on the stationary bike became possible a few days ago, and suddenly I can think about actually riding again. Can't wait!
Knee update: I'm off the crutches and am using a Bledsoe Brace for walking across snow and ice. A full rotation on the stationary bike became possible a few days ago, and suddenly I can think about actually riding again. Can't wait!
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