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Han Broekman
Lived in Wageningen, Netherlands
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Han Broekman

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+Maarten Broekman This looks cool !!!
 
forgot the name of the movie
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Short Circuit!  Number 5 is alive!
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Han Broekman

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L2 and the James Webb Space Telescope

The James Webb Space Telescope (red) will orbit the Sun at a special gravity island called L2 (Lagrange Point 2).  L2 is located 1,519,000 km beyond the Earth (blue).

Ordinarily, being further from the Sun would mean that a spacecraft would orbit the Sun more slowly, and it would quickly fall behind the Earth. However, the spacecraft feels the combined gravity of the Sun and Earth, and a stronger pull of gravity means a faster orbit. If the distance is just right, the increased orbit speed causes it to match the Earth’s orbit speed, and it stays permanently in the Earth’s shadow.

For those who are interested in how location of the L2 point is computed, see here: http://www.maththoughts.com/blog/2011/l2-what-is-it-and-where-is-it/
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Han Broekman

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Oh that University PR office ...
 
The Science News Cycle

This week's Best of PHD Theme: Science and the Media
http://tapastic.com/episode/18523
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Han Broekman

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An edgy mural adorning at CERN is a hipper, more accessible take on the ground breaking physics being conducted there.
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Fantastic weather on 2013-04-27.  Went to Harriman State Park for a short hike to find some cemeteries.  Only found one, Waldron cemetery off Seven Lakes Drive near the Sebago Lake boat launch.  We then went on to West point & took a tour of the USMA (picture of parade grounds).
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Have him in circles
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Han Broekman

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L2 and the James Webb Space Telescope

The James Webb Space Telescope (red) will orbit the Sun at a special gravity island called L2 (Lagrange Point 2).  L2 is located 1,519,000 km beyond the Earth (blue).

Ordinarily, being further from the Sun would mean that a spacecraft would orbit the Sun more slowly, and it would quickly fall behind the Earth. However, the spacecraft feels the combined gravity of the Sun and Earth, and a stronger pull of gravity means a faster orbit. If the distance is just right, the increased orbit speed causes it to match the Earth’s orbit speed, and it stays permanently in the Earth’s shadow.

For those who are interested in how location of the L2 point is computed, see here: http://www.maththoughts.com/blog/2011/l2-what-is-it-and-where-is-it/
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Han Broekman

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Absolutely gorgeous!
 
Making the Pentafleur lamp

The main lamp body has 62 faces: 12 pentagons, 20 triangles, and 30 squares. If you look carefully, you'll see that three additional polyhedral shapes are revealed by the pattern of the kumiko (the latticework frames to which the paper is glued):
1) The icosahedron, which is made up of 20 triangles.
2) The dodecahedron, which is made up of 12 pentagons.
3) And the Catalan deltoidal hexecontahedron, which is the dual of the rhombicosidodecahedron and is made up of 60 kite-shaped faces. (Each vertex of the dual touches a face of the original.)

Ingredients:
285 pieces of maple
705 pieces of mahogany
705 dowels
296 pieces of washi (shoji paper)
470 neodymium disc magnets
77 wood screws
23 lamp hardware parts
1 dozen audiobooks
4 pinches of patience
2 jiggers of stubbornness
1 dash of insanity

Recipe:
1) Calculate the dihedral and miter angles
2) Build cutting, drilling, and gluing jigs
3) Plane maple planks to width
4) Rip maple with table saw and bandsaw (for the dihedral angles) to create 100' of frame stock, as well as the five lamp stand legs
5) Rout 100' of rabbets, 55' of round-overs, and one 5' groove (to run the cord in one leg)
6) Sand with power palm sander
7) Make 2,000+ cuts with power and hand miter saws
8) Make fine angle adjustments with a spindle sander and fine length adjustments with a disc sander
9) Glue up 1,000+ joints using clamps and jigs
10) Drill 1,200+ holes using jigs and freehand
11) Glue in 1,100+ dowels and magnets
12) Sand with a drum sander and by hand
13) Add a coat of finish
14) Add two more coats of finish, hand sanding between each
15) Assemble
16) Plug in
17) Light!

If you're interested to read more about the making of the Pentafleur, visit http://goo.gl/lm8bfV

Enjoy!
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I had bought a Mountek nGroove CD slot iPhone Grip <http://www.mountek.com/dp/B004G1L52Q>.  Seeing it sit on the table next to my laptop, I got the idea for an iPhone stand, using a 3/4" rare earth magnet I had laying around (it had lost most of the cheap chrome finish) and some oak scrap pieces.  Works beautifully for me ...
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Fantastic idea!! Looks great!
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The new coffee table is complete and just about finished.  There are some assemble time scratches to work away.  The top is 46 1/2" x 22 3/4". The leg portion is 43 3/4" x 19 3/4" x 19 1/2" LxWxH.  The space between the upper shelf and the glass top is only 2 3/4". 

This design is borrowed from Karl Caillouet and his coffee table (such as <http://ewoodshop.com/sofa-table/>), with modifications for our room and setup, as approved by higher authority!
#coffee_table
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Nice work, Han. I like the beveled edges of the top.
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Have him in circles
213 people
Lieuwe Jongsma's profile photo
Earl Krause's profile photo
Marilyn Guthrie's profile photo
Steve Racz's profile photo
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Wageningen, Netherlands - Utrecht, Netherlands - Cambridge, MA - Queens, NY - Floral Park, NY - Fair Lawn, NJ
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Introduction
I retired from a 35 year job researching mechanisms of diseases like stroke and heart disease.  I strive to become a more proficient woodworker.
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