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Showing posts from January, 2020

Bryophyta Monilophyta Lycophyta walk and trek

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The walk began will me up a Premna obtusifolia tree collecting the fertile frond of Davallia solida, a dimorphic fern. Fertile frond of Davallia solida Moss with sporophytes Davallia pectinata Davallia pectinata The class as seen from my tree, studying the handout Jordan, Christian on lead   I lingered longer in the east as there is more to be seen there. That said, we were late to head west at 16:12. And the trail is all but gone - traffic is very light now on that once busy route. Passage was slower going and more treacherous than expected. A downed Falcataria moluccana, and an unexpected hole along the slope hidden in the grass. Barringtonia asiatica Barringtonia asiatica Asplenium laserpitiifolium Possibly peipei eni, but not confirmed. Species uncertain.  Phlegmariurus phlegmaria but still Huperzia phlegmaria on the class handout. I am not yet much in favor of the PPG 1 splitting and consequent renaming Hapl

Acceleration day two

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After the numbers generated on day one did not well support a numerical approach to d=½at² I opted to start the second day by returning to last week and the relationship that for a constant velocity the equation is d = vt and on a time versus distance graph there is a constant slope, a constant velocity. The initial velocity v₀ is the same as the final velocity. Transferred to a time versus velocity graph the data produces a slope equals zero horizontal line. On the board above the material to the left of the dotted line is a recap of the previous week.  Then I recapped what I was trying to do on Monday : start from a speed v₀ equals zero and then go faster and faster in a linearly increasing rate of increased velocity. On Monday I left as unknown what shape might be produced on a time versus distance graph if the velocity increased at a steady rate versus time. On Monday the data produced a half of a parabola. What I could not know on Monday was whether my velocity had inc

Acceleration day one

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Summer 2019 I read Steven Strogatz's Infinite Powers: How Calculus Reveals the Secrets of the Universe . I was reminded that the earliest steps towards calculus were taken by those who were trying to solve physical science problems. And their approaches were both algebraic and geometric in their reasoning. I realized I could retool my approach to acceleration from a more Galilean approach, to not provide the quadratic regression from the get go on day one, but to edge into this relationship more carefully. To build more slowly from the material of the second week, and to not presume that a parabolic curve is the automatic result of a constant increase in speed. I began class on Monday by sketching a time versus distance graph onto the board with a speed of 1.69 meters per second found from the RipStik run of the previous Monday. I then sketched a time versus velocity graph for a constant velocity of 1.69 m/s on the board. I noted that on this graph the velocity is on

Linear velociy

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Linear velocity opened with a RipStik linear velocity run of 30 meters done in meters and seconds. This occupied the second half of the period - the first half was devoted to covering the quiz. Selfie from atop the RipStik Data was recorded onto a poster pad and then entered into Desmos and analyzed. Wednesday the students learned to use the chronographs and were to determine their walking speed by duplicating Monday's 30 meter RipStik run. No homework was assigned, but students were asked to obtain their speed from a linear regression against their split times. Thursday the ball was rolled slow, medium, and fast with timings taken at one meter, three meter, and then five meter intervals. Wind and rain led to experimenting with rolling the ball west. This worked well under the conditions. Sample three ball data. The week wrapped with another quiz.

Ethnobotany and iNaturalist start up spring 2020

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This term featured an expanded up front early exposure to digital resources in the course and iNaturalist. Day one still landed during and drop. I handed out the syllabus , the final examination , and a sheet listing some of the useful apps related to the course. The weather was good, so I took the class out for a short introduction to the plants on the east end of the campus. I later generated an iNaturalist bounding box for the area of the walk which includes some of the plants seen. I noted as I worked on the bounding box the absence of the larger trees in the box on iNaturalist. The trees are more challenging to capture in diagnostic photos. Fall 2019 I attempted to introduce iNaturalist by having the students first engage in identifications and then engage in observations. Two separate issues arose. One was that a profile with no observations may be ruled a spam account by the spam detection engines in iNaturalist. Two was that the students seemed to have difficulty g

Mars and Murrie

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For a eighth term the MS 150 Statistics course began with a problem solving open data exploration leading to a presentation. The exercise effectively flips the role of the students from that of being students in a class to that of being statisticians reporting on their statistical findings. This shift allows the instructor to begin the second week of class by saying, "I know you already know how to calculate statistics and make charts..." This gives the students an early sense of success and a sense that they can succeed in the course. This term the petty cash limit and MM price increases led to an 88 bag start For fifteen years the statistics course started with gathering data on body metrics and then launching into a lecture driven course. In 2008 I added statistics projects to the lecture and test mix in an attempt to both increase student engagement with statistics and to integrate more writing into the course. The statistics projects did not result in incre