Wednesday, August 30, 2006

Recovering Energy, Part Deux

It has come to my attention, through my friend Simon, that perhaps I was too glib and a tad misinformed regarding the power characteristics of jet engines. There are a lot of variables to consider, and simply saying stating the thrust of an engine doesn't tell you all you need to know (unless you're on the Senate Arms Committee).

Here is a cool reference on jet engine ratings, and Wikipedia has a nice page on jet engines. It seems that maximum thrust is not constant with airspeed .. but it doesn't go down linearly either, so you're still better off in the power game than with piston engines.

Simon also thought my main point about energy and driving was a bit muddied, so I'll restate it here.

Constant acceleration requires linearly increasing power .. until you are working against drag, in which case it takes, uhh, quartic power? Exercise for the reader: drag goes as speed squared, so power to move against drag goes as speed cubed.. so what about accelerating against drag?

Similarly, constant deceleration requires linearly decreasing power. Since a hybrid can only recover a maximum amount of power, the deceleration you can invoke that does not dissipate power goes as 1/speed. Lift off the gas at 60 MPH and you're maxing out the Civic Hybrid regenerator, ditto for touching the brakes at 30 MPH. And standing on them at 5 MPH only barely gets you there (but there's not enough energy at 5 MPH to care about anyway).

This is not the way I want to train myself to drive, nor would I like it as a passenger. I just hope we don't have a generation [sic] of hybrid drivers with their eyes glued to the regen meter while they're braking.

Tuesday, August 29, 2006

Recovering Energy

Reversing the acceleration profile is Not Smooth!

Let me explain. Part of the fun of how calculus, physics, and getting your driver's license all happen at roughly the same time in high school is how nicely these disciplines all mesh together.

F=ma explains so much, like how constant power becomes decreasing acceleration with speed. (And, coincidentally, how stating jet engine performance in terms of thrust instead of power explains their speed advantage over pistons and propellors.)

You can think of it many different ways, but the fact that kinetic energy goes as the square of speed means that the same acceleration takes more power at higher speed. This is why you never feel like you have enough power*.

Similarly, the amount of energy dissipated by constant deceleration goes linearly with speed. Gears mean nothing in braking - you get the same deceleration from your brakes regardless of speed, but they heat up faster if you are braking from speed.

Woa, woa, woa.. gears mean nothing unless you want to recover energy instead of dissipating it! Hybrids use regenerative braking to recharge their batteries. And just as there is a limit to how much power they can add for acceleration, there is a limit to how much power they can absorb.

Which means that just lifting off the gas on the freeway pegs the regen meter .. and just touching the brakes at 30 MPH pegs the regen meter .. and you basically have to stand on the brakes at 5 MPH to register at all.

Oops. This is not the way I or any passenger wants to be driven around. Have you ever been in a car with someone who saves their hardest braking for the end? Not Fun (and very disconcerting on the track, I might add).

So now I'm wondering how many hybrid drivers are going to let their driving habits be governed by the energy gauges in their cars? Kind of a scary thought..

* "When you can lay two black stripes between the exit of one corner and the entrance of the next, then you have enough power" - Mark Donohue

Friday, August 25, 2006


I've only been to Hawaii a few times, but I definitely have a favorite island. Actually it's a place on an island, because the island is The Big Island (Hawaii).

That place is Kailua-Kona, aka Kona. It's the home of the Iron Man competition, some really cheesey souvenier shops, and perhaps the best snorkeling in all of the islands.

We got into this place by accident, really. We signed up for a points-based timeshare (Vacation Internationale, if you care), which gives us time at whatever condos they have in their system (more time off-peak, etc). And their place on Hawaii is on the west coast, just south of Kona.

And also just north of a fantastic snorkeling area. The usual amazingly colorful fishes abound, and we have visited with sea turtles many times.

Kona also is a stopping point for at least one cruise line. The boat shows up on Monday, hangs around for a couple days, and then steams off into the sunset. At some point in my life I should take a cruise..

Most Hawaiian islands have varied micro-climates, and they appeal differently to different folk. Californians tend to favor the east coasts, with their daily rain and lush vegetation. Northwesterners get quite enough rain in their lives, thank you very much, and opt for the west coasts.

If condos aren't your bag, about an hour north of Kona is the Waikaloa Hotel, which is swanky etc - how many hotels do you know have an interior water slide? You'll be visiting the area anyway, because very close to it is Hapuna Beach, a very wide beach with a gentle slope into the sea ... and huge waves. We're talking close-the-beach, occasional fatality huge.

Our routine for Kona is pretty simple. United flys there non-stop from SFO, and you arrive in the early afternoon, with time to load up with the week's food at the Costco on the way to Kona. This is also where I pick up my customary cheap Hawaiian shirt.

After that, it's swim/read/sleep/eat - the condos have a bank of Weber grills, and nearly every meal is a cookout.

Damn, it's only August - I want to go there now.

Thursday, August 24, 2006

Driving a Hybrid

So I have a week of driving this Civic Hybrid under my [seat] belt. I want to talk about the Navi system, but I need to grok it more before talking about it - just yesterday I poked around and learned about a cool feature.

There's the dynamic driving part, too, like how well it rides and corners. My first impressions still hold, that its steering is very direct and with good feel, and that it is surprisingly well-balanced for a front-engined car.

It does push (understeer) a bit when it gets near the limit, as expected, but it's not nearly as much as I would expect for a mass-market car. I still want to find a stiffer rear anti-roll bar so that I feel more comfortable in turns.

And why should you care about cornering well? Excellent question, glad you asked!

Hybrids are all about efficiency and recovering energy. People have such misconceptions about what wastes energy while driving. The proverbial jack-rabbit start does not inherently waste energy. Think about it - it takes the same amount of energy to reach 40 MPH whether you accelerate quickly or not.

The energy considerations of the jack-rabbit start have to do with 1) enrichment of fuel mixture under heavy throttle, 2) the thermodynamic efficiency of engines at various throttle settings, and 3) energy loss through an automatic transmission.

Roughly speaking, 1) enrichment takes more fuel, though not as much as in the days of carburetors and "accelerator pumps", 2) Carnot-cycle engines are typically most efficient at 60% speed and 60% throttle, and 3) slip is bad - think of holding still on an upgrade, wasting energy going 0 MPH.

I've spent way too much time on acceleration. The biggest expenditures of energy are 1) drag and 2) throwing heat away through the brakes.

Hybrids have tiny engines and are very aerodynamic. This is so they can be working harder (and more efficiently) at speed, and to reduce the drag at speed. No matter what your aerodynamics, drag still goes up as the square of speed, power required goes up as the cube, and mileage goes down as the square. So, if you get 40 MPG at 60 MPH, at 80 MPH you'll get (3/4)^2 of that, or 22.5 MPH!

This does not bode well for hybrid economy in Si Valley, where CA-85 seems to be a nickname for the speed you have to go on it to avoid being run over.

Now, finally to braking, and my original mention of cornering. Hybrids attempt to recover energy during braking by using the electric motor as a generator instead of just the brakes. It has a maximum generation capacity, however, so if you need to slow down faster, it's going to require the brakes.

The Civic Hybrid has a smaller battery and generator than the Prius, and you have to brake very gently indeed to avoid actually invoking the brakes.

Better not to have to slow down at all, I say! This is where racetrack and car control training come into play. The fastest way around a corner is also the smoothest, and it's important to take the right line through it. It sounds simple - and it is - but you'd be surprised how many people do this completely wrong. Like most of you. Yes, I'm talking to you .. next time you're on the road, try looking ahead more and driving smoothly.

As three-time world driving champion Jackie Stewart says, a good race driver is also a good chauffeur - the passenger shouldn't be able to tell exactly when she starts braking, turning, or accelerating. To go fast on the racetrack (and on the freeway on-ramp), you go slow in the cockpit.

And when you're driving a hybrid, go easy - very easy - on the brakes, and give the car the best chance possible to do its magic.

Click here for more advice on how to maximize Civic Hybrid fuel economy.

Tuesday, August 22, 2006


I should probably explain the title of this blog. Grok of course is a verb invented by Robert A. Heinlein in Stranger in a Strange Land that is a combination of absorbing, understanding and, well, eating an idea or person.

To grok something is to have taken it in, tasted it, internalized it. To truly, uh, grok this concept, do read this beautiful and thoughtful book that touches on humanity, religion, politics, and thought.

What does this have to do with Unigrok? Heh, well I guess I just wanted to embellish the concept of grokking and give it an official-sounding corporate flare. As Wile E. Coyote would say, "Universal Grok, Inc .. I like the way that rolls out .."

Unigrok is also the name of an XML application server I wrote a few years ago. I'll describe that too, after I resurrect It was/is very cool, very expressive, very compact. It may fall short of the integrated detail of later works like Ruby on Rails or TurboGears, but it felt all of one piece. And I miss it when I encounter today's web app languages.

I suppose another interpretation would have the uni part mean not universal but one. But ugh, understanding one thing reminds me of The Hedgehog Principle, a concept put forth in a truly odious book on business,
Good to Great. Which BTW I am listing here only so you can see the comments on Amazon .. do not buy this book! And if a prospective employer is run by someone who believes in it .. run!

Monday, August 21, 2006

Civic Hybrid with Navi!

Well! After watching the progress of hybrid cars - and waiting for a model that actually comes in my size - I finally took the plunge and ordered a Honda Civic Hybrid. 45mpg city/highway or some such.

This was 7 months ago.

Ordinarily, and even in California, the waiting list for things like this isn't nearly this long, but as long as I was going to get something "special" I thought I would go for the cool navigation unit. Which apparently is a rare commodity. More on this soon.

But first, the wait. My first salesman, who is no longer with the dealer ("perhaps your car will arrive in my son's lifetime"), thought it would show up in 5 weeks rather than the normal 2-3 weeks for the regular model. Longer if I cared to specify the color.

So I thought it was fine. I wasn't sure I could afford a new car just then, and I wasn't sure I wanted to give up my current ride (and I'm still not). But after 3 months passed without a word from the dealer, I started getting concerned. They had $500 of my money and I wondered if they were giving priority to new customers who offered extra money.

So every month or so I'd pay a visit to the dealer. No word, and they don't find out what's coming until the day before it shows. Don't you think Honda would understand about supply chain management? I sure do.

Time continues to pass and I start thinking about checking other dealers in other states. When I finally did check, the next day I got The Call, my car had arrived, and couldn't I run over and finish buying it.

Say, what? You make me wait for 7 months and you expect me to re-arrange my life with a phone call?

It got worse. I visited the dealer after work and was immediately asked to sign a bunch of papers.

"Can't I see the car first?"

"Um, oh, sure..."

So I see what it looks like in my non-favorite color. Hmm. Well, okay. Let me think about it. "No, no, please sign the paperwork!" Any by the way put down all of your bank accounts etc in the credit application. Nothing like being treated like you're fresh out of high school.

By this time it's 8pm, I hadn't gotten a decent night's sleep in 4 days, and I just wanted to go home. The salesman wouldn't let me.

"No, no, people have come by and offered more money!"

"Why are you so worried about me not getting this car? The worst that can happen is I don't buy it and you can make $3K more selling it to someone else."

Finally the finance manager either took pity on me, noticed my gray hair and realized maybe they should treat me better, or just decided to stop the salesman at .95 Jerk, and they let me walk out uncommitted.

And I came in the next day and bought the car. As I said, it came in my size (although we'll have to do something about thigh support), the navigation system is ultra-cool (and the voice activation covers the radio and A/C too!), and it drives really well (although I've already decided it needs a stiffer rear anti-roll bar).

I just wish the purchasing experience was more pleasant. 7 months of uncertainty and non-communication followed by 2 days of high pressure just isn't a good customer experience, and I had expected more of Honda.

Wednesday, August 16, 2006

Vonage, Take II

Well! 15+ years after we all failed to get AT&T the least bit interested in the Internet, I, ex-Bell Labs employee and long-time AT&T customer, have at last given up on Ma Bell and its recent mutation/resurrection. I made my first Vonage phone call today.

It was sort of a non-event, though the notion of getting a dial tone from router-appendage is taking some getting used to. BTW please raise your hand if you really understand where dial tone really comes from and what it's for.

It's taken many years and "The Will to Fail" (as Andrew Hume used to put it), but AT&T has at last managed to plow itself into the ground.

For a while in the 90's I was rather amazed to be getting 4 or 5 bills from AT&T. Let's see, there was my phone bill, my cable bill, my Universal Card bill .. there must have been more. That all vanished except for my silly insistence on keeping A&T for long distance. All of $10/mo or so.

When I moved to Si Valley last year, I was fairly insistent on getting DSL. Static IP, known upstream bandwidth, all that. It took a goofy, unwanted router and psychotic customer non-service to disabuse me of that notion. That was SBC, which has since bought the AT&T label and calls itself The New AT&T.

My internet comes through Comcast (don't get me started), yet my SBC/AT&T bill was $100 for two lines with voicemail etc. I expect to pay $15/mo for VoiP .. and I'm only doing that because I want to accept incoming POTS calls.

The old AT&T's worst fears have come to pass. Back when telecom was starting to lose its regulation, AT&T wanted to charge extra for data. Never mind it was using 64Kbps to transmit your voice at 8KHz. Actually, it mattered quite a lot, because this was AT&T's equivalence for purposes of calculating rates. If you leased a T1 line (1.4Mbps, or 24 times 64Kbps), AT&T wanted to charge 24 times the rate of a voice line because you could use it to bypass their network.

As Sandy Fraser (who invented Virtual Circuits) used to say, they were afraid that if they had to charge a reasonable amount for data, they'd have to give voice away. That pretty much sums up the state of things now - AT&T retreated from everything except Long Distance, which became a worthless commodity and was AT&T's epitaph.


Monday, August 14, 2006

Vonage - Two Line Adapters

I'm on the phone with Vonage customer service right now. After deciding to stop paying $100/mo to SBC/AT&T for two-line service that I essentially don't use, and seeing that Vonage could transfer my existing phone numbers, I decided to take the VoIP jump.

Hoo boy, the more things change...

I used to work for The Phone Company, or at least its research arm (Bell Laboratories), and my first-day experience with Vonage brought with it a creepy sense of deja vu.

I had studied the network phone adapters available, and was pleased to discover one that could handle both of my phone lines. So, when I finally decided to take the plunge, I knew exactly what plan ($15/mo) and which adapter to get.

Great, one number down, one to go. Basically you set up one number first and add the second later. No sweat, I'll just .. wait a minute, why isn't their web site letting me not get another network phone adapter? I just want to add another line to the adapter they're already going to send me.

So I poked and prodded at the site, and couldn't un-check the radio button. Drat. Well okay, the adapter is $50, but there's a $50 rebate, and maybe I'll find a use for an extra one. Clicking Continue I realized that in my pokings I had accidentally chosen the $25/mo plan for line two.

No sweat, I'll just switch plans.. but oops, changing plans costs $10. There must be something wrong with that. Two emails later it's clear that no, Vonage won't simply switch me back even though I sent the request minutes after getting the wrong selection.

The irony of course is that I was trying to save them money. Sheesh.

Okay, so 45 minutes on the customer service line later, they cancelled the second line so I can start from scratch. Oops, but they can't actually refund my money .. no, they applied a credit to my account that should get used up in, oh, four months.

Well at least I'll only get the one network phone adapter, which was the whole point, and .. oops, what's this second shipping notification and tracking number in my mailbox? Sure enough, Vonage cancelled the second line, and I didn't re-order it, but they're sending me a second adapter anyway.

This is astonishingly messed up. I've been a Vonage customer for a week and I already have a weirdly entangled and still unsettled account with them.

And I have yet to actually make a phone call.

Sunday, August 13, 2006

The End of Faith

Sam Harris has been shaking people up recently. His book The End of Faith has stirred up a lot of controversy, not the least for his assertion that religious moderates are more to blame for the current culture wars than the religious extremists actually killing people.

Here's a 20 minute talk he gave recently on the subject. I like his use of the term calling a spade a spade, which are exactly the words I've been using in hopes that the spineless democrats in the US will finally stand up and stand for something.

Harris' book starts out as a vigorous polemic that says 1) most of the horrors visited by man upon himself have roots in religion, and 2) religions are fundamentally intolerant, especially of other religions.

My simple logic has always been that if one religion is right, the others all have to be wrong. Therefore none of them are right.

Interestingly, his last chapter muses on the curious divide between East and West on the notions of consciousness and religion. Why, he asks, has Western thought never left the dogma stage, always asserting there's a Higher Being that we talk to in prayer, whereas Eastern thought has explored the nature of consciousness and studied the many levels possible?

Saturday, August 12, 2006

Kate Bush - Aerial

This is my favorite CD.

My previous exposure to Kate Bush was her contribution to Peter Gabriel's Don't Give Up.

I know, I know, Kate Bush has been a phenomenon ever since her debut in 1978. But it wasn't until the VH1 guy on CBS Sunday Morning gushed over Aerial that I took the plunge.

Wow, what a record! It starts out with King of the Mountain, which I didn't know until later was a tome about Elvis (and I hadn't taken the cue of her slurring her words like The King).

why does a multi-millionaire
fill up his home with priceless junk?
the wind is whistling through the house

How to Be Invisible is another great track. There is so much ambience and presence to the music, you're just set up to be swept into her words.

take a pinch of keyhole
fold yourself up
cut along the dotted line
you think inside out
you're invisible..

The second CD (what, I didn't mention it's a double album?) is all of one piece, a glorious celebration of sky and its inhabitants. From Sunset to Somewhere In Between with a touch of Kate doing a chirping duo with an Aerial Tal, you are simply and utterly transported to another world.

somewhere in between the waxing and waning wave
somewhere in between the night and the daylight
somewhere in between the ticking and the tocking clock
somewhere in between what the song and the silence say
somewhere in between breathing out and breathing in

Mind Science

This is a great talk! Set an hour aside for a brief history of science and its near-complete, willful ignorance of mental phenomena.

B Alan Wallace started the Santa Barbara Institute, which at first glance might seem like a fuzzy, new wave endeavor (it must be a coincidence that USA Network's new Psyche TV comedy detective show is also set in SB). However, Alan is a Physics PhD who wants to get started on applying the scientific method to the study of the non-physical stuff that happens and lives in our brains.

What is consciousness? What is thought? Sure, memories are chemical RNA encodings, but how do we perceive them? How do you measure these things? How do you tell if things are even happening if all you have is the first-person account of the one experiencing them?

Well, here's a start. Richard Davidson at U of Wisconsin did fMRI's of meditating Buddhist monks and saw some remarkable things. Interestingly, the effects were directly correlated with the amount of training - tens of thousands of hours - of the individuals in the study.

So, what's going on with these monks? They're working to achieve Enlightenment, but there's a measurable physical effect. Alan wants to study this further, by colocating these professionally trained folk with scientific observation. Maybe he can come up with the F=ma of mental phenomena .. wouldn't that be great!

For my part, I want to take a shortcut to enlightenment (little 'e'). There are so many styles of meditation, and it's so hard to concentrate without concentrating on concentration, etc. "Be aware of your breathing", "as each thought rises, note it and let it go".. there are dozens of little instructions like this buzzing around in my head when my mind should be otherwise working its way to another level of consciousness.

This all reminds me of Peter O'Toole's character in The Ruling Class, who decides he is Jesus Christ because he discovered while praying that he was talking to himself.

Wouldn't it be great to have bio-feedback during meditation? Forget all the rules, forget being frustrated that "it isn't working for me", just get straight to recognizing the feeling of changing your consciousness and learn how to deepen the experience. Sign me up!

Two Left Turns

No, this isn't a political discourse. This is a rant on the nearly universal, mindless unskillfulness that I see on the road every day here in Si Valley.

Si Valley is famous for its growth, and in many ways for ungraceful growth. But, show me another area with such limited space that has gone from groves of fruit trees to suburbia cum industrial park that has managed to support the amazing increase in traffic.

And it has built and rebuilt this support. I still marvel at the cloverleafs on Central Expressway that were (and often still are!) one square block of neighborhood.

Another aspect of this support, and the one I'm talking about here, is the double left turn lane at most major intersections. The leftmost lane is for left and U turns, while you can only turn left in the rightmost left turn lane.

It turns out that people do something else in the leftmost turn lane. And that, to my continuing horror and annoyance, is turning too early in the first part of the turn, only to have to pinch it in the last part so that 1) the clueless driver can mostly stay in the proper lane and 2) the clueless driver can avoid T-boning the car in the other left turn lane.

Why oh why do people do this. Over and over, completely unable to figure out the cause? Just when they should be unwinding the steering and accelerating, they are slowing down, jinking the steering wheel, unsettling their passengers, and frightening the person in the next lane (that person would be me).

Repeat after me. Start by going straight and turning the wheel slowly. Your path should be a quarter-circle and you should not repeat not have the feeling you are running out of road at turn's end.

It's really easy to get rid of this bad habit. Trust me, I have instructed dozens of people in exactly this skill on the racetrack. Guess what, this is also one of the secrets of going fast... but that's another post.