e From:	IN%"cmkrnl.com!jeh@rutgers.UUCP"  "Jamie Hanrahan, Kernel Mode Systems" 10-MAR-1993 04:06:32.59  To:	IN%"TERRY@spcvxa.spc.edu"  CC:	 Subj:	RE: Need some Quote's   * Return-path: <cmkrnl.com!jeh@rutgers.UUCP>C Received: from VN-GATEWAY by spcvxa.spc.edu (PMDF V4.2-7 #042B2) id C  <01GVMOD94OYO8WW0IS@spcvxa.spc.edu>; Wed, 10 Mar 1993 04:04:06 EST N Received: from mimsy.UUCP by rutgers.edu (5.59/SMI4.0/RU1.5/3.08) with UUCP id%  AA24802; Wed, 10 Mar 93 03:00:41 EST N Received: by mimsy.UMD.EDU (smail2.5) id AA15114; 10 Mar 93 03:00:21 EST (Wed)M Received: from uunet.uu.net (via LOCALHOST.UU.NET) by relay2.UU.NET with SMTP H  (5.61/UUNET-internet-primary) id AA24518; Wed, 10 Mar 93 02:45:14 -0500N Received: from cmkrnl.UUCP by uunet.uu.net with UUCP/RMAIL (queueing-rmail) id+  024454.6639; Wed, 10 Mar 1993 02:44:54 EST O Received: by cmkrnl.com (DECUS UUCP /2.0/2.0/2.0/); Tue,  9 Mar 93 23:38:31 PST + Date: Tue, 09 Mar 1993 23:38:31 -0800 (PST) I From: "Jamie Hanrahan, Kernel Mode Systems" <cmkrnl.com!jeh@rutgers.UUCP>  Subject: RE: Need some Quote's To: TERRY@spcvxa.spc.edu2 Message-id: <0096945C6888DB60.000012DB@cmkrnl.com> Content-transfer-encoding: 7BIT * X-Vms-Mail-To: UUCP%"TERRY@spcvxa.spc.edu"2 X-Vms-Mail-Cc: UU%"_hanrahan@eisner.decus.org",JEH  D > Do you have the one called "A Fable Concerning Product Design and   > Implementation"?  Starts with:  J Attached.  I'll post it on DECUServe also.  Might prompt a whole series of similar things.   L >   Nope - I'd appreciate it. Also, note my post said "can't do general dis-K > tribution". That means if one of my friends asks (like you), I can make a K > tape with the whole mess. Just ask. I can do 1600/3200/6250 tapes (free), J > TK50's (you supply the tapes), DC6250's in Unix "tar" format (likewise), > amd 4mm (90m, compressed).  , How about TK50's - how many should I send?    6 	--- Jamie Hanrahan, Kernel Mode Systems, San Diego CAB Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055  N ------------------------------------------------------------------------------  4 A FABLE CONCERNING PRODUCT DESIGN AND IMPLEMENTATION  J Consider a custom automobile production shop which is run as its analog inD programming might be.  Let us take an order and follow it through toI completion.  This particular order will be for a special high-performance L racing car, a low-profile, 180 mile-per-hour job for oval track racing.  TheK customer has given the description to the shop.  A fixed-price bid has been  submitted and accepted.   M Three automotive engineers are available.  Two of them decide that the engine I will be the trickiest portion, so they begin debating ways to operate the J valves.  In talking about the system, they draw diagrams on a chalkboard. N These diagrams are of two kinds:  Fuel flow diagrams and cam timing diagrams. J These are the only design tools available, so they use them all the time.   L The third engineer is a specialist in springs.  He goes out to the shop and,O with a welding torch, starts piecing together a suspension system.  He develops H a combined leaf and coil system with trailing torque arms and transverseM torsion bars that is the best ever produced.  He then moves on to the problem I of propulsion and begins toying with schemes for a spring-driven, wind-up L engine.  He has already started building this when the others, coming out toM the shop to start building the intake manifold and valve assemblies, tell him 8 that it is impractical.  He sits down and just watches.   J Shortly the two senior engineers decide that they need a distributor. TheyM carefully specify its size and shape and the material it is to be made of, as L well as its maximum rotational speed and voltage and current tolerances. TheJ idle engineer then isolates himself in his office to develop it.  There heL notes how elegant it is to divide a circle into six arcs using a compass and# settles on a six-cylinder pattern.    L The engine is built from front to rear.  When the eighth in-line cylinder isM reached, the two engineers start designing the attached floor and body.  This L is not easy with fuel flow diagrams, so they simply start building without aN design.  Halfway through they find that their floor plan is too narrow for theJ elaborate rear suspension. Since it is already built, they are hesitant toK throw it away; they angle the body outward so that it is wide enough at the G rear.  Noting that they will need a transaxle, they build that assembly  integral to the body pan.   K The distributor has been completed and is fitted into place.  A debate then O ensues about whether the engine was supposed to have six or eight cylinders.  A O compromise is reached:  The engine will have seven active cylinders; the eighth N cylinder will be a dummy, and cylinders one and seven will fire together.  TheM electrical system is modified to accommodate the extra surge.  Later, another N engineer suggests the ingenious idea of using the eighth cylinder as a pump toO power hydraulic wipers and windows.  As an added feature, the doors are made to  operate hydraulically too.    N On delivery to the customer, attention is drawn to the unusual wedge shape andN to the convenience of hydraulically operated doors.  He is told how clever theO hookup of the eighth cylinder is and that it will only be a minor inconvenience M to have to leave either the engine running or the doors open.  Later he finds K that strict adherence has been made to his original specifications; the car J only turns left (for counter-clockwise ovals).  When an attempt is made toJ change this, it is learned that the steering gear and motor housings are aO single piece.  Since there is no access door, the engine has to be cut open, at O considerable cost.  But aside from the fact that the two halves of the steering N wheel are of slightly different diameters and that the wipers will not operateO with the windows up (due to a glitch in the hydraulic network), the customer is  reasonably satisfied.   O The shop, meanwhile, has lost its collective shirt, largely because of the time G and effort spent experimenting with various wheel shapes before finally " settling on the optimal -- round.    (end) 