Zap's New Writeupshttp://everything2.com/?node=New%20Writeups%20Atom%20Feed&foruser=Zap2002-05-17T18:47:32ZWhich way did the bicycle go? (idea)http://everything2.com/user/Zap/writeups/Which+way+did+the+bicycle+go%253FZaphttp://everything2.com/user/Zap2002-05-17T18:47:32Z2002-05-17T18:47:32ZGiven a <a href="/title/bicycle">bicycle</a> track - can you tell which way the <a href="/title/bike">bike</a> went?
<p><a href="/title/Sherlock+Holmes">Sherlock Holmes</a> <a href="/title/goof">goof</a>ed on this <a href="/title/problem">problem</a> in "<a href="/title/The+Adventure+of+the+Priory+School">The Adventure of the Priory School</a>". He argued that the <a href="/title/rear+wheel">rear wheel</a> would make more of a <a href="/title/depression">depression</a> than the <a href="/title/front+wheel">front wheel</a>, but that does not <a href="/title/resolve">resolve</a> the issue of direction.
<p>There is a nice <a href="/title/geometrical">geometrical</a> <a href="/title/solution">solution</a> to this problem. It uses two aspects of a normal bicycle:
<ol>
<li>The front and back <a href="/title/wheel">wheel</a> are separated by a constant distance.
<li>The rear wheel always points to the point where the front wheel touches the ground.
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Item 2 implies that the <a href="/title/tangent">tangent</a> of the rear wheel track should <a href="/title/intersect">intersect</a> the front wheel track at a given distance that is <a href="/title/unknown">unknown</a> but <a href="/title/constant">constant</a> for any given bicycle (as noted in item 1).
<p>It is therefore helpful to know which track is which, but <a href="/title/trial+and+error">trial and error</a> would sort out which of the four possible combinations is correct (front/back track, and one of two directions) after we have looked at a number of tangents from<!-- close unclosed tag --></p><!-- close unclosed tag --></p><!-- close unclosed tag --></p>…Saline nasal lavage (thing)http://everything2.com/user/Zap/writeups/Saline+nasal+lavageZaphttp://everything2.com/user/Zap2002-05-10T19:52:04Z2002-05-10T19:52:04ZA surprisingly effective way to deal with <a href="/title/allergic+rhintitis">allergic rhintitis</a> (<a href="/title/hayfever">hayfever</a>) - just wash those <a href="/title/pollen">pollen</a>s and other <a href="/title/allergen">allergen</a>s away!
<p>After my most recent bout with <a href="/title/hayfever">hayfever</a>, my <a href="/title/allergist">allergist</a> gave me a new little <a href="/title/gadget">gadget</a> in addition to the numerous <a href="/title/drugs">drugs</a> that I take to stay functional. It looks a little like something you might pick up in the <a href="/title/adult+toy">adult toy</a> department (mine is pink), but once you see past that it is a useful little thing.
<p>The gadget is a <a href="/title/tube">tube</a> about 8 <a href="/title/centimeter">cm</a> long, fitted with a <a href="/title/nozzle">nozzle</a> that fits in a <a href="/title/nostril">nostril</a> (see below). The thing is filled with a <a href="/title/salt+solution">salt solution</a> while held <a href="/title/horizontally">horizontally</a>, you place your <a href="/title/thumb">thumb</a> over the <a href="/title/open">open</a> <a href="/title/hole">hole</a>, fit the <a href="/title/nozzle">nozzle</a> to a <a href="/title/nostril">nostril</a> while leaning forward, let the thumb let go and slowly return towards an <a href="/title/upright">upright</a> position.<tt><!-- close inline tag into block --></tt><pre><tt><!-- reopen inline tag after block -->
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<p>At the correct angle the salt solution starts<!-- close unclosed tag --></p><!-- close unclosed tag --></p><!-- close unclosed tag --></p>…Fluctuation-dissipation theorem (idea)http://everything2.com/user/Zap/writeups/Fluctuation-dissipation+theoremZaphttp://everything2.com/user/Zap2002-05-09T16:48:10Z2002-05-09T16:48:10ZA <a href="/title/fundamental">fundamental</a> result in <a href="/title/statistical+physics">statistical physics</a> which links <a href="/title/microscopic">microscopic</a> (thermal) <a href="/title/fluctuation">fluctuation</a>s with the <a href="/title/macroscopic">macroscopic</a> property that creates a <a href="/title/drag+force">drag force</a> on a <a href="/title/particle">particle</a> in a medium.
<p><a href="/title/Browninan+motion">Browninan motion</a> is often expressed using a particle on which two distinct <a href="/title/force">force</a>s act:<br>
ma=-g x v(t) + f x G(t),<br>
where "g" is the <a href="/title/drag+force">drag force</a> when the particle has <a href="/title/velocity">velocity</a> "v(t)" and "f" is a constant that dictates the influence of the zero-mean (usually Gaussian white) noise component "G(t)".
<p>However, and this is the point of this <a href="/title/theorem">theorem</a>, the drag force is dependent on the noise component and <a href="/title/thermodynamics">thermodynamic</a> consistency requires that
<br>
f=sqrt(2*g*k*T),<br>
where 'sqrt()' represents a square root, "k" is <a href="/title/Boltzmann%2527s+constant">Boltzmann's constant</a> and "T" is the <a href="/title/temperature">temperature</a> in <a href="/title/Kelvin">Kelvin</a>.<!-- close unclosed tag --></p><!-- close unclosed tag --></p>Pasta with grape tomato sugo rosso (thing)http://everything2.com/user/Zap/writeups/Pasta+with+grape+tomato+sugo+rossoZaphttp://everything2.com/user/Zap2002-05-07T20:03:28Z2002-05-07T20:03:28ZThis is a super-simple, yet really delicious <a href="/title/pasta+sauce">pasta sauce</a>. To me, this is the taste of summer. It should take a total of about 20 minutes to prepare and cook this dish.
<p><b>Ingredients</b> (for four): this <a href="/title/recipe">recipe</a> has no more than three ingredients (not counting the oil!), thus qualifying for my definition of a <a href="/title/bachelor-friendly+recipe">bachelor-friendly recipe</a>.
<ul>
<li>One half <a href="/title/liter">liter</a> (about one <a href="/title/pint">pint</a>) <a href="/title/grape+tomato">grape</a> or <a href="/title/cherry+tomato">cherry tomato</a>es. You can use a little more if you like more sauce to cover your pasta.
<li>Four <a href="/title/garlic">garlic</a> <a href="/title/clove">clove</a>s.
<li>One half <a href="/title/kilo">kilo</a> (about a pound) of <a href="/title/pasta">pasta</a>.
<li>Three <a href="/title/tablespoons">tablespoons</a> of good <a href="/title/olive+oil">olive oil</a>.
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<p><b>Directions:</b>
<ol>
<li>Boil plenty of salted water for the pasta.
<li>Peel and slice the garlic thinly.
<li>Cut all the grape tomatoes in half.
<li>Heat the olive oil in a not-too-hot <a href="/title/skillet">skillet</a>.
<li>Add the sliced garlic, do not burn!
<li>Toss the pasta into the boiling water so that it is ready at about the same time as the sauce.
<li>Add the tomatoes to the<!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></li><!-- close unclosed tag --></ol><!-- close unclosed tag --></p><!-- close unclosed tag --></p>…seisiún (thing)http://everything2.com/user/Zap/writeups/seisi%25C3%25BAnZaphttp://everything2.com/user/Zap2002-05-06T21:42:59Z2002-05-06T21:42:59ZIrish for a <a href="/title/session">session</a> - a gathering of musicians (and <a href="/title/punter">punter</a>s) to enjoy some <a href="/title/Irish+traditional+music">Irish traditional music</a> using implements such as <a href="/title/simple+system+flute">flutes</a>, <a href="/title/fiddle">fiddle</a>s, <a href="/title/uillean+pipes">uillean pipes</a>, <a href="/title/tin+whistle">tin whistle</a>s and (possibly one and no more) <a href="/title/bodhran">bodhran</a>s.
<p>The seisiún has its own set of rules. On the surface it appears to be a <a href="/title/chaotic">chaotic</a> gathering, but under that there is a good bit of <a href="/title/etiquette">etiquette</a> that you are better off knowing about and adhering to.
<p>The best first thing to do when you come across a session is to sit down and listen, even if you are really eager to get going on playing yourself. What are they playing? What kind of style is dominating the seisiún? What is the level of the players? Only if you feel that you can hold your own and blend in well should you ask to sit in.
<p>Once in the circle of musicians, remember that you are a guest. Jump in when the tunes you know are played, but always listen more than you play.
<p>All rules aside - good <a href="/title/craic">craic</a> (or crack) is always the desirable end<!-- close unclosed tag --></p><!-- close unclosed tag --></p><!-- close unclosed tag --></p><!-- close unclosed tag --></p>…Theobald Böhm (person)http://everything2.com/user/Zap/writeups/Theobald+B%25C3%25B6hmZaphttp://everything2.com/user/Zap2002-05-06T21:15:25Z2002-05-06T21:15:25ZA <a href="/title/Bavarian">Bavarian</a> court <a href="/title/musician">musician</a> and <a href="/title/innovator">innovator</a>. Böhm (Boehm) designed important new types of flutes in 1832 and 1847. He was born in <a href="/title/M%25C3%25BCnchen">München</a> in 1794, he died in 1881.
<p>Until 1831, Böhm built and performed on eight-keyed flutes. But on a visit to London he met others interested in devising new <a href="/title/acoustic">acoustic</a> models for the flute that used mechanical means to alter its fingering.
<p>The 1832 invention redesigned the placement of keys on the flute to allow the use of larger finger holes. By starting from scratch and asking how holes and keys needed to be placed on the flute to allow for an in-tune three octave range, he invented the basis for the <a href="/title/modern+flute">modern flute</a>. Since no human could cover the proposed <a href="/title/hole">hole</a>s with their fingers it was then necessary to devise a system of keys and levers to open and close the holes as required by his calculations.
<p>The 1847 invention changed the <a href="/title/conical+bore">conical bore</a> of the flute to one with a <a href="/title/cylindrical+bore">cylindrical bore</a> instead. The joint was furnished in a (slightly) <a href="/title/parabolical">parabolical</a><!-- close unclosed tag --></p><!-- close unclosed tag --></p><!-- close unclosed tag --></p>…