## Posts

Showing posts from January, 2010

### Beyond 200 minutes

In the spring of 2009 I moved beyond pedometers and into an effort to tally 200 minutes of running per week. The target of 200 minutes per week was a result of a previously found relationship between a seven day pedometer average and my seven day total running time.
A month into the 200 minute program and initial results were promising. The key indicator was a three month weighted average of my seven day total time statistic. The goal was 200 minutes per week, but not a Sunday to Sunday basis. I used a spreadsheet to track my seven day total running time each and every day. A simple seven row sum function handled this. Each day I could calculate how many minutes I needed to maintain 200 minutes of running.
The three month weighted average consisted of a 50% weight on the average of the most recent thirty days worth of the seven day total time, one-third on the prior 30 days, and one sixth on the thirty days before that. Thus the average was a three month span, but with half the weight …

### Nett Point in January

While El NiÃ±o puts the deep freeze on north america, europe, and siberia, Pohnpei continues to provide reasons for letting go of an unhealthy attachment to the four seasons. Here are three of those reasons.

One.
Two.
Three.
Try striking a pose soaking wet while outside in Omaha right now.
Continental on roll-out at the end of the runway. The work being done is on an extension to the runway.

### Dropping the ball: Acceleration of gravity

Laboratory 032 involves timing the fall of a ball to determine the acceleration of gravity g.

Cecelia drops the ball while Brigida observes.

Eliander is the dropper-timer while Steward secures the meter sticks.

Mayleen and Irene work along the laboratory windows.

Nick and Kesusa work on top of a table to get drops as high as 300 cm. The final drops are made from a balcony outside that provide drop heights of 400 and 500 centimeters.
Data from the laboratory (OpenOffice.org Calc file).

Nancyleen working with Cecelia.

### Stiking together

A family should really Stik together through the bumps and falls in life.

We are working on a "flight formation" routine where we sweep down slope
together with proverbial "36" inch cockpit-to-wingtip separation in
echelon and diamond formations. The we split or cross-over.

For reasons that baffle me, mass is playing a role in our downhill speeds. In the underlying physics the mass cancels out - the old feather and hammer fall at the same rate in a vacuum physics experiment. And no, air resistance is not a significant differential factor at the speeds we attain, a mere two meters per second at best. So when we do a formation turn the least massive has to be on the inside, with the middlemost massive in slot, and myself on the outside of the curve. More massive is faster in the world of caster boarding down slope.

I tend to fall more often than the other two, but I view my re-acquaintance with the ground in a positive light.

Learning to rebalance oneself seems to more…

Totoa Fetalai-Currie led a lively presentation on the use of plants on Pohnpei. She began with tumeric and led into a discussion of plants that can be used in curry.

The presentation covered plants for food, healing, construction, and decor.

The class listens to Totoa.

Plants were passed around and local names elicited.

Totoa holds Cyathea nigricans.

Totoa with assistant.

### RipStik in physical science: accelerated linear motion

In a previous article I shared the use of a RipStik in SC 130 Physical Science to demonstrate linear unaccelerated motion. The ability to generate a relatively constant velocity by swizzling at a constant rate on level ground was useful to that demonstration. In this demonstration I accelerated the RipStik from rest over a distance of 9.2 meters using columns that were 4.1 meters apart. Measuring the time as I passed each column permitted a calculation of the average speed between each column.

A student captured the image above. The external light and lack of a flash meant that the image had to be processed using a retinex filter in GIMP to lighten the foreground relative to the background. My watch can be seen in my right hand, I used the chronograph feature to capture the split times.

This demonstration required that I accelerate, which meant swizzling faster and with more force than the previous constant rate swizzle. This required more skill than last week. The time and distance dat…

### Teaching riders to learn

The two young women were watching my son and I ride RipStiks on campus. They seemed interested in trying to ride, so I offered them a chance to try one out. As one tried to stand on the RipStik, the other steadied her by holding her hands. As soon as the supporter let go, however, the rider immediately lost balance and fell off without making any forward progress. They repeated this approach a couple of times.

My son, meanwhile, went whizzing by, taunting, "See, it's easy!"

Without giving any thought to my action, I suggested another approach. I asked if the young woman if she was right or left-handed. She was left-handed. So I switched her to a goofy foot stance. Then I told her to put her right foot on the front plate with the RipStik pointed down a very shallow slope. I told her to focus her vision not on where she was going but on the back plate of the RipStik. I told her to lift her left foot onto the back plate while focusing on that plate. Then she could look ahead…

### Lycophyte and monilophyte presentations

Students in SC/SS 115 Ethnobotany gave presentations on the botany and local names of cyanobacteria and the primitive plants.

The cyanobacteria covering Nostoc was one of the best and most detailed I have seen in recent terms.

Carleen and Marsela put together the poster presentation, their coverage was both thorough and comprehensive.

Jeffrey, Fritzgerald, and Leah covered the morphology of Lycophytes.

Yvonne Sue and Jessica presented on the life cycle of ferns.

Adam and Sweeter did a comprehensive and entertaining job on covering monilophyte morphology, with a focus on ferns.

For the first time in the history of the course plant names in Marshallese were presented, albeit tentatively and not specifically primitive plants. A more comprehensive list exists on the Plants and Environments of the Marshall Islands web site.

Marcia and Vanessa present primitive plant names in Kosraean. For both this was a learning experience, few youth in Kosrae know the names of their plants in their own langua…

### RipStik evening

An eight to five day in physical science laboratory and ethnobotany class led to a sunny evening decision to hit a local parking lot and rip with my son. The light was fading when I caught this grainy image of him coming off of our local equivalent of a manual pad on his RipStik.

Rolling by in the gathering dusk.

### Rolling balls and linear relationships

Physical science laboratory two was revised this term to include five different rolling ball speeds including stationary.

The ball being rolled is actually a four square ball. Syd-Lee launches the four-square ball and Tracy holds the "curling" broom.

Keicyleen and Vanessa on the left timing line, Nicole and Jessica on the right line. Krystal can be seen trying jump clear of the ball.

The 8:00 lab used stopwatches to determine the second marks, the 11:00 repeated the experiment but replacing stopwatches with oral counts of the seconds using "one-one thousand..."

To my surprise, the 11:00 data had a higher correlation than the 8:00 data. One major confounding complication: rain forced the 11:00 session into the practice gym and onto the practice gym carpet.

After taking measurements at the gym, the class moved to A204 to enter data. Tracy enters data in the image above.

### RipStik in physical science: simple linear motion

Having been taught by my son to ride a RipStik® over the holiday break, I deployed this new skill in physical science class. In the past I rolled a marble past equidistant points on a table. This was easily replicated in an elementary school classroom and remains a useful demonstration. The demonstration, however, lacked any excitement, no pizazz. This term I rode a RipStik past columns that were 4.57 meters apart, timing my split times with a chronograph.

Only one of my students had seen a RipStik before - this is still a remote Pacific island -  and all quickly realized that there was a reasonable possibility of their instructor falling to the ground. Falling down in Micronesia is simply not done, even if the cause is an attempt to do something new. To some extent, one is supposed to practice in private and deliver perfection in public. So risking falling in the middle of campus had my students riveted on my 46 meter ride.
Time (s)
Distance (m)
0
0.0
2.74
4.6
7.16
9.1
10.76
13.7
14.36
18.3
17.81
2…

### Ethnobotanical garden clean-up

Students cleaned up the Palikir Student Ethnobotanical garden.

The students both clean-up the garden by pulling and cutting the weeds and they work on learning the names of the plants in their own language. Later we will focus on uses of the plants, the students will also have to perform a matching exercise for the Latin names of the plants.

Marcia and Joannie study Senna Alata.

Joannie.

Marsela working up in the eastern section of the garden.

Sweeter raking.

Pulling.