Humans' oldest known art form is a pornographic sculpture of woman made of mammoth ivory, 47ky old. Somewhere around that time, or maybe half as old, humans domesticated dogs (and vice-versa).
But only when humans learned to farm, which is much more productive than hunting and gathering, when they accumulated grain stores, did cats notice them. Because if you have grain you have mice and cats become your friends, and friendly, besides.
So humans have bred dogs for tens of thousands of years and recently it was proposed that Chihuahuas be designated a separate species from say New Foundlands. Cats remain unencumbered by this highly unnatural selection.
26 May 2009
Feline Service Provider
My cat will sometimes demonstrate why California allows cats to be uncollared and unlicensed and free-roaming: he kills rodents. More occasionally a lizard or bird.
This AM I was in the downstairs bathroom and noticed a live mouse at the top of the shower. He had climbed the shower-hose. He was not happy.
Most of the time I only find a fractional mouse in the shower. At least its easy to clean up.
I tried to free the climbing mouse but he got loose when I did. I have freed rabbits, mice, hummingbirds, and regular birds from cats. I hope the cat gets the mouse soon though.
Once the cat got just the tail of a lizard. Sometime later I saw the lizard in the house, and let him go.
Tried to find the Ca law. Found this amazing site
http://www.animallaw.info/statutes/stuscacalfishgcode3005_9_31766.htm#s9
which is militant pro-cat.
This site
http://www.abcbirds.org/abcprograms/policy/cats/materials/cat_law.pdf
is cat-hostile.
There are many oppressive sites that claim cats should be indoors only. That is just wrong. They should have fluffy pillows to sleep on when they want though.
And for those that can handle it, occasional catnip in moderation.
Special skills
Special skills: I can catch a boomerang I've thrown. Several times in succession. I started in the late 1980s at UCI and can still do it. It is very fun to teach others to throw. There is a Scientific American article on the physics, which is utterly fascinating.
Recreational x-rays
I slept in, when I awoke the wife and kid were working on a science
project where they detailed the life of a scientist. They had
chosen Bill Roentgen !!!
I helped them with the gist ---it was an accident, he was goofing
with HV and tubes and had a fluorescent screen that flickered.
(I keep insisting that if they write "barium platinocyanide" that they
explain its fluorescent, which is the point... do not pretend
that chemical is common knowledge..)
Anyway, I managed to reconstruct my 5-year dormant x-ray system in the time it took them to work the report. Tried one tube, nothing.
Another, I got some CDV700 clicks but no meter change. I started to take pictures, and after a few shots I noticed that the meter had in fact increased. Slow integration time! And/or tube changes due to heating. I went back to the first tube, and got better results.
A $15 russkie blink & click detector was useless. The CDV700 was better, audible clicks and eventually the meter moved. Up to 0.05 mR/hr on the 100x scale, at 19cm, yawn. But an integrating ionization chamber used by dentists registered about 0.1 R/sec (!!!!) At 10 cm. To be conservative I have to believe the
strongest measure. I have no NIST calib.
I had been annoyed at myself for buying the integrating x-ray detector at first, as its poor (though slowly responsive) on rocks etc; but for x-rays its great, it turns out.
The hazard of course is my lack of isolation from 110V mains; the rad is on very little time, and I have a m between us, and its just me.
The mains AC is totally OSHA unapproved.
The coil coupling to the tube is via a small artifactual spark gap and the CDV700 clicks were coupled to the sparks; so unsure of dose per pulse. I have bolts in the HV terminals of the coils, and aluminium foil connecting the base pins, and an aluminum foil cap acting as a capacitor to the getter or tube top. Standard _Bell Jar_ stuff.
(I've read that Bill R had 8 pulses/sec and only ~30kV from his
Oudin coil; I'm using antiparallel ignition coils, a light dimmer, and some series 300V caps to pass just the transients from the dimmer.)
"Keep one hand in your pocket" --ALANIS MORISSETTE
The power supply is an AC dimmer (ie SCR gating the AC mains) series connected into a few 300V caps fed into antiparallel ignition coils. The dimmer makes abrupt transitions and the caps pass the transitions; the coils step up the voltage.
Running the system. Note the geiger counter (on 10x) and the x-ray meter (measuring R!!)
25 May 2009
Squid BBQ
Barbequed a squid (from Zion Market, Irvine) last night, came out great. Dusted it with sucrose and salt, stopped heat early. Also cooked some Korean mushrooms I'd never worked with, came out great. Zion has quite cheap vegetables and of course lots of weird exotic items. At least half a dozen different kinds of squid jerky. Live fish, snails, etc. I love SoCal.
24 May 2009
Fish
When I was a kid we fished a stream for horned daces, a small minnow like fish.
Later we had a pond with bass, and I fished that. Even made my own lures.
Eventually I stopped because of the cruelty.
My (upstate NY) grandfather used to fish for trout. I've seen trout in the local SoCal creek, which amazed me. (A few metres from the stream, it was standard semi-arid chapparal.)
I like to eat trout.
My favorite fish is salmon, and I've learned to salt it, to make gravlox. Never caught one though.
I like oily fish, including mackerel, and find bland fish completely boring.
I've caught an ocean mackeral once.
I let the kid catch trout in the mountains in a captive (ie lame) trout pond. We took em home, dissected them, and ate them. This was good, albeit an extremely fake fishing experience. (Time to catch: about 30sec per fish) I had to discretely kill the landed fish so as not to traumatize the kid.
I continue to worry about cruelty, preferring to behead lobsters, crabs, etc cleanly. I only hope I will die similarly painlessly & quickly. I've attended
a pig vivisection, the pig was anesthetized and never woke up. That is perhaps more moral than simply eating them (it was for medicine) but I love bacon and eat pork freely. I've also petted a friends pet pigs. Its a coherent philosophy/morality for me. Way back when, I saw terminal heart surgery on a dog, which is weird: its a dog, ie a "pet", and its surgery (with drapes etc), and the ribs looked good enough to eat, if wrapped in plastic at a grocery.
Later we had a pond with bass, and I fished that. Even made my own lures.
Eventually I stopped because of the cruelty.
My (upstate NY) grandfather used to fish for trout. I've seen trout in the local SoCal creek, which amazed me. (A few metres from the stream, it was standard semi-arid chapparal.)
I like to eat trout.
My favorite fish is salmon, and I've learned to salt it, to make gravlox. Never caught one though.
I like oily fish, including mackerel, and find bland fish completely boring.
I've caught an ocean mackeral once.
I let the kid catch trout in the mountains in a captive (ie lame) trout pond. We took em home, dissected them, and ate them. This was good, albeit an extremely fake fishing experience. (Time to catch: about 30sec per fish) I had to discretely kill the landed fish so as not to traumatize the kid.
I continue to worry about cruelty, preferring to behead lobsters, crabs, etc cleanly. I only hope I will die similarly painlessly & quickly. I've attended
a pig vivisection, the pig was anesthetized and never woke up. That is perhaps more moral than simply eating them (it was for medicine) but I love bacon and eat pork freely. I've also petted a friends pet pigs. Its a coherent philosophy/morality for me. Way back when, I saw terminal heart surgery on a dog, which is weird: its a dog, ie a "pet", and its surgery (with drapes etc), and the ribs looked good enough to eat, if wrapped in plastic at a grocery.
Other home chem experiments
If you add boric acid (roach powder) to methanol (petro dewatering agent) you
get green flame. Its very cool and I used it last Halloween to amuse visitors.
If you make charcoal you can make black powder. A coffee grinder or mortar and pestle helps. Also, you will learn about the importance of moisture and pressure in the quality of the powder. This is not an explosive, just a propellant, unless you confine it. In fact its just a campfire starter if its slow. I actually made
charcoal from plants I grew in the backyard, and the suburban gas fireplace.
Long ago, everyone knew charcoal and its variants, but nitre was tough, made from natural deposits. Now, charcoal making is a lost art but nitre can be bought pure from Home Depot, as stump remover.
If you mix magnetite sands (mined from the beach with a magnet) with aluminum powder, you can make thermite. You can grind the sand in a coffee grinder too.
Always make only a small amount, wear eye protection, use long bbq lighters.
Copper sulphate can be bought from Home Depot as root killer. Mixed with eg baking soda you get copper carbonate, a nice greenish pigment. Other salts are similarly blue or green. They stain porous materials eg plaster quite well. Clorides, acetates, etc are easy too, using common household materials.
None of this impresses my 9 year old terribly, he probably thinks every dad does this.
My mom had a chemistry set, which is pretty amazing. So did I as a kid.
There are other things you can make that go boom, for real, a brisant boom,
involving iodine and ammonia, or silver nitrate and acetylene, or even peroxide and acetone. But those would be dangerous (in various ways) to make.
I've also made yellowcake from uranium ore that I got from the desert.
(And used geiger counters to track it.)
There are more dangerous chemicals under the sink, or used for pools.
Car accidents kills more kids than any other cause. Yet folks drive their kids to trivial things.
I've tried making guncotton but I don't have (and haven't distilled) nitric acid and so it didn't work.
Amateur science is very important. All the STEM (sci, tech, engineering, math) hype won't work unless kids are excited. When I 'retire' (an obsolete, 20th century concept) I might teach science. And/or computer science. Meanwhile I'm a practicing engineer with unusual hobbies.
Speaking of which: out on Trabuco there is a model-airplane flying club, the Trabuco Flyers. I've paused to watch their aerobatics, very cool. They use nitromethane, an explosive (if done right) to fuel airplanes with 2m spans+. The horror!
Heck, even mountain biking is dangerous, I know a guy whose mouth was wired for a month because of a biking accident. And I've known someone who died in a private plane crash. And how many kids break bones, get brain damage, die of cardiac failure, or heat stroke, from "sports"? Before modern medicine, a broken bone might well be a death sentence or at least a lifetime crippling event.
Oh, and I've made x-rays using ignition coils and vacuum tubes. Even taken pictures with them.
And measured the density of gasses using an alpha-particle source and mica-windowed geiger counter.
And graphed the decay of radon using (freely distributable, open source) software I wrote, combined with a 1960's yellow civil defense geiger counter.
Kid injuries so far: chipped tooth from a friend in a swimming pool.
get green flame. Its very cool and I used it last Halloween to amuse visitors.
If you make charcoal you can make black powder. A coffee grinder or mortar and pestle helps. Also, you will learn about the importance of moisture and pressure in the quality of the powder. This is not an explosive, just a propellant, unless you confine it. In fact its just a campfire starter if its slow. I actually made
charcoal from plants I grew in the backyard, and the suburban gas fireplace.
Long ago, everyone knew charcoal and its variants, but nitre was tough, made from natural deposits. Now, charcoal making is a lost art but nitre can be bought pure from Home Depot, as stump remover.
If you mix magnetite sands (mined from the beach with a magnet) with aluminum powder, you can make thermite. You can grind the sand in a coffee grinder too.
Always make only a small amount, wear eye protection, use long bbq lighters.
Copper sulphate can be bought from Home Depot as root killer. Mixed with eg baking soda you get copper carbonate, a nice greenish pigment. Other salts are similarly blue or green. They stain porous materials eg plaster quite well. Clorides, acetates, etc are easy too, using common household materials.
None of this impresses my 9 year old terribly, he probably thinks every dad does this.
My mom had a chemistry set, which is pretty amazing. So did I as a kid.
There are other things you can make that go boom, for real, a brisant boom,
involving iodine and ammonia, or silver nitrate and acetylene, or even peroxide and acetone. But those would be dangerous (in various ways) to make.
I've also made yellowcake from uranium ore that I got from the desert.
(And used geiger counters to track it.)
There are more dangerous chemicals under the sink, or used for pools.
Car accidents kills more kids than any other cause. Yet folks drive their kids to trivial things.
I've tried making guncotton but I don't have (and haven't distilled) nitric acid and so it didn't work.
Amateur science is very important. All the STEM (sci, tech, engineering, math) hype won't work unless kids are excited. When I 'retire' (an obsolete, 20th century concept) I might teach science. And/or computer science. Meanwhile I'm a practicing engineer with unusual hobbies.
Speaking of which: out on Trabuco there is a model-airplane flying club, the Trabuco Flyers. I've paused to watch their aerobatics, very cool. They use nitromethane, an explosive (if done right) to fuel airplanes with 2m spans+. The horror!
Heck, even mountain biking is dangerous, I know a guy whose mouth was wired for a month because of a biking accident. And I've known someone who died in a private plane crash. And how many kids break bones, get brain damage, die of cardiac failure, or heat stroke, from "sports"? Before modern medicine, a broken bone might well be a death sentence or at least a lifetime crippling event.
Oh, and I've made x-rays using ignition coils and vacuum tubes. Even taken pictures with them.
And measured the density of gasses using an alpha-particle source and mica-windowed geiger counter.
And graphed the decay of radon using (freely distributable, open source) software I wrote, combined with a 1960's yellow civil defense geiger counter.
Kid injuries so far: chipped tooth from a friend in a swimming pool.
My oldest net posting
October 1987
http://catless.ncl.ac.uk/Risks/5.42.html#subj5.3
First quarter of grad school.
http://catless.ncl.ac.uk/Risks/5.42.html#subj5.3
First quarter of grad school.
Plant
This is a plant that grows up in the San Bernadino mountains. It looks like ringworm and no doubt follows the same rules, expanding outwards. (See also fungal fairy circles). Also reminds me of the Belousov–Zhabotinsky reaction.
Cheap wide-angle lens for point-and-shoots
High res digital point and shoot cameras are extremely convenient.
Some tricks:
You can use a hardware-store door-viewer as a wide field lens once you learn to hold it correctly.
You can also use a screw (in the camera body) and a string (which you step on) as a stabilizer. I haven't done this but its very clever.
Back in the day of silver and hiking with friends, I used to haul a 35mm SLR with a big wide angle zoom. Its nice not to have to open your delicate optics to change film in a dusty, windy environment.
Some tricks:
You can use a hardware-store door-viewer as a wide field lens once you learn to hold it correctly.
You can also use a screw (in the camera body) and a string (which you step on) as a stabilizer. I haven't done this but its very clever.
Back in the day of silver and hiking with friends, I used to haul a 35mm SLR with a big wide angle zoom. Its nice not to have to open your delicate optics to change film in a dusty, windy environment.
Calcium acetate
Dissolve eggshells in vinegar, then crystallize.
Interestingly, if you heat calcium acetate, you get acetone.
Also, calcium acetate is a drug used for kidneys.
For sale
A neighbor was selling a large blue canvas. I thought it made a hilarious backdrop.
A catapault I hacked together for the kid
Subaru
(Since I've expanded this blog to include hobbies..)
The Subaru up Santiago Canyon
Painting a beach using a magnet to separate magnetite
Cat picture
Lets face it, Al Gore invented the Innertubes so that we can watch cats ride Roombas.
Here is my obligatory cat picture.
You might be an embedded software engineer if..
You might be an embedded software engineer if your cube looks like this
Trabuco creek, trout
Past two weekends I've taken the Subaru Forester up Trabuco Creek trail. The first time I went all the way to the end, HorseThief trail. There is still water flowing. Saw some tadpoles. And I saw a trout in a 3m wide little pool. Next weekend I took the kid with me, and we saw a few more trout, and a salamander. Also some nice butterflies and dragonflies around the water. And some nasty looking water beetles that try to eat small fish.
Some pictures follow.
21 May 2009
Medical vs. Commercial software
Commercial software is released when the marketroids say so. Medical software is released when you can defend yourself in court ---meaning testing, procedures, QA, documentation, skill, etc.
What is dangerous is when commercial software is used in life-critical apps, eg some vulnerable software is used by a contractor for a nuclear reactor.
I took classes with Dr. Nancy Leveson and roomed with Dr. Clark Savage Turner. I later read the Therac papers, worked for a defibrillator company, and later an electrosurgical instrument company. None catastrophic; though the chief scientist at the place I now work at has worked on aircraft systems, as have the two other founders.
I worked on a video kludge for some obsolete hardware there, nothing critical at all.
The defib code and the ESG / ESU code could hurt one or two people, nothing major
catastrophic, but still enough to be superuseful and somewhat or slightly dangerous.
I was not a lead, in fact, brought in fairly late, in the case of the defib; but I am
the lead on the ESU.
In a few years my software could run a tool being stuck into your inflated abdomen. I will do my best to make it do as told.
What is dangerous is when commercial software is used in life-critical apps, eg some vulnerable software is used by a contractor for a nuclear reactor.
I took classes with Dr. Nancy Leveson and roomed with Dr. Clark Savage Turner. I later read the Therac papers, worked for a defibrillator company, and later an electrosurgical instrument company. None catastrophic; though the chief scientist at the place I now work at has worked on aircraft systems, as have the two other founders.
I worked on a video kludge for some obsolete hardware there, nothing critical at all.
The defib code and the ESG / ESU code could hurt one or two people, nothing major
catastrophic, but still enough to be superuseful and somewhat or slightly dangerous.
I was not a lead, in fact, brought in fairly late, in the case of the defib; but I am
the lead on the ESU.
In a few years my software could run a tool being stuck into your inflated abdomen. I will do my best to make it do as told.
19 May 2009
If the internet was a building
If the internet was a building, the first woodpecker to come along would take it down.
Not my idea, but I subscribe.
Not my idea, but I subscribe.
17 May 2009
Amusing progress message from Wolfram
Checking out Steve Wolfram's "Alpha", I got this message. Check out the
progress indicator. "NaN" means not a number.
13 May 2009
Joys of hardware
Yesterday felt ill, went home, slept, went back to work. Felt better than I had
in a week. Today, went in early, found several hardware problems. I'm trying to
make a build sufficient for ESD testing, and it turns out to accelerate the integration
testing, four PIC boards talking RS485 to an ARM, on an isolated bus.
Good to be back at work. Still seeing 2pm fade-out. Dealing with it.
in a week. Today, went in early, found several hardware problems. I'm trying to
make a build sufficient for ESD testing, and it turns out to accelerate the integration
testing, four PIC boards talking RS485 to an ARM, on an isolated bus.
Good to be back at work. Still seeing 2pm fade-out. Dealing with it.
09 May 2009
Another hobby: Cooking
Another hobby, I realize, is cooking. I particularly enjoy BBQ, and have used since 1998 a propane unit. Previously I've used a very cool ceramic japanese charcoal-fired bbq that some friends gave as a marriage present, and before that, a hand me down hibachi. I used to entertain friends at my grad school apartment after a long hike, and BBQ was the thing. Now that I'm a family man I still like to BBQ. Its a grand chemistry experiment that you can eat. With the control afforded with a propane grill its a thermo experiment as well. I tell you what.
08 May 2009
Hairspray cannon III
Well, after demonstrating a number of concussive firings I found that the cardboard
cylinder that a household abrasive cleaner is packaged in is just under the correct
bore, caliber 73mm or so. On my first launch out of my shorter "gun" I shot
the comet cylinder a good 4m and over a wall. It hit a palm. Very cool! Reminds me of the first beer-can shot with my first tube, surprisingly good results. Nice parabolic arc. Harmless fun.
I'm also experimenting with pure butane from an ITAWANI cartridge, which is a japanese thing. I like unusual (to me) food; I go to Mitsuwa, a japanese grocery in Costa Mesa, when I can. I always get fried squid, and either a bento or a sashimi & rice dish they have. Usually I take it back and eat at my desk. Anyway, cylinders of butane for small stoves are pretty cheap there.
Actually, hairspray seems to be best. Its probably the isobutane propellant.
Hairspray cannon II
I used the half-opened bottom of a mixed-nuts tin over the current tube, and got a nice bang. Quite distinct from the whoomph. Very cool. Replicates earlier experiments and observations.
I hot-glued the defunct lighter into the shorter tube, so it looks like
a gun. That goes whoomph and spews a fireball. Nice. With the anti-silencer (ie half-opened can on the muzzle), you get a nice boom instead of a quiet whoomph. Will have to experiment with aperatures vs. acoustics.
Even cooler: after you fire it, the muzzle continues to burn off residual fuel.
Glows blue. Nice.
Hairspray canonn
Last trash day,
I was delighted to find that a neighbor was throwing out massive cardboard
tubes used as cores I think for tiling of some sort. Anyway I was needing
fodder for my hairspray cannon experiments. I'm not sure whether aspect ratio
matters or simply fuel:air mix. I have not yet been able to produce a concussion
with the new tubes. I could do this with a previous tube when I put
a potato-chip tube with a D-shaped metal part cut out of the end, leaving a D shaped
occluder. Without the partial occluder I got the same "whoomph" that I'm getting now. That difference (bang vs. whoomph) fascinated me; I've thought about reflection physics, thermo, detonation theory, etc.
The percussive setup would be great for 4th of july, very safe, legal, yet loud and boomy.
The new tubes are of sufficient diameter to hold a BBQ igniter module I had once bought, but which didn't fit earlier tubes. They are nearly 1/4" thick, I have to use a drill to make a hole in them. For either the igniter module or an exhausted
disposable BBQ lighter which still sparks. You can also ignite the tube with
a regular lighter, but since you're not blocking the touchhole, you get flame
from the touchhole (danger!) and limited compression.
I keep thinking that Blue Man Group needs to use pyro acoustics.
I've also never successfully launched & ignited Cremora powder, which is supposedly a nice optical fireball.
Campbell's soup plastic bowls are the proper size to block the breach. With friction. I've not yet found a nice-fitting projectile ---previous tube fit a large beer perfectly-- but am working on this. A good piston seems to enhance the efficiency greatly. We once cleared the house, which takes 30km/sec. This was with a small water balloon on top of a 24oz beercan inserted to its depth in the tube. Fired vertically.
Its both a tedious distracting pain and an interesting challenge to find proper-fitting accidental components. No art without constraint.
I need to find the right fuel:air for a full 6' tube and a piston. I might also
experiment with chokes, eg soda bottles that neck down the diameter of the tube.
Or expanders, eg trumpet flares, which are impedence converters, ie transformers, couplers.
Its fun to have a kid you're trying to interest in things, a smidgen of income and time, and some dangerous knowledge. Not even beginning to mention the trouble you can get into on eB*y or the innertubes in general.
This is Freeze-It hairspray, cardboard tubes, and a lighter. When I was a kid
I didn't know about this. Now, you can find Youtube tutorials...
I was delighted to find that a neighbor was throwing out massive cardboard
tubes used as cores I think for tiling of some sort. Anyway I was needing
fodder for my hairspray cannon experiments. I'm not sure whether aspect ratio
matters or simply fuel:air mix. I have not yet been able to produce a concussion
with the new tubes. I could do this with a previous tube when I put
a potato-chip tube with a D-shaped metal part cut out of the end, leaving a D shaped
occluder. Without the partial occluder I got the same "whoomph" that I'm getting now. That difference (bang vs. whoomph) fascinated me; I've thought about reflection physics, thermo, detonation theory, etc.
The percussive setup would be great for 4th of july, very safe, legal, yet loud and boomy.
The new tubes are of sufficient diameter to hold a BBQ igniter module I had once bought, but which didn't fit earlier tubes. They are nearly 1/4" thick, I have to use a drill to make a hole in them. For either the igniter module or an exhausted
disposable BBQ lighter which still sparks. You can also ignite the tube with
a regular lighter, but since you're not blocking the touchhole, you get flame
from the touchhole (danger!) and limited compression.
I keep thinking that Blue Man Group needs to use pyro acoustics.
I've also never successfully launched & ignited Cremora powder, which is supposedly a nice optical fireball.
Campbell's soup plastic bowls are the proper size to block the breach. With friction. I've not yet found a nice-fitting projectile ---previous tube fit a large beer perfectly-- but am working on this. A good piston seems to enhance the efficiency greatly. We once cleared the house, which takes 30km/sec. This was with a small water balloon on top of a 24oz beercan inserted to its depth in the tube. Fired vertically.
Its both a tedious distracting pain and an interesting challenge to find proper-fitting accidental components. No art without constraint.
I need to find the right fuel:air for a full 6' tube and a piston. I might also
experiment with chokes, eg soda bottles that neck down the diameter of the tube.
Or expanders, eg trumpet flares, which are impedence converters, ie transformers, couplers.
Its fun to have a kid you're trying to interest in things, a smidgen of income and time, and some dangerous knowledge. Not even beginning to mention the trouble you can get into on eB*y or the innertubes in general.
This is Freeze-It hairspray, cardboard tubes, and a lighter. When I was a kid
I didn't know about this. Now, you can find Youtube tutorials...
07 May 2009
Cats
So I'm sitting on the loo and the cat brings in a mouse. I don't have my
glasses on but I quickly perceive that its alive. Its also not pleased.
Bottom line: it escapes.
glasses on but I quickly perceive that its alive. Its also not pleased.
Bottom line: it escapes.
05 May 2009
Another lingo collision
Fuse. A fuse in an electronic device can be irreversibly blown, opening a circuit. This is used for thermal protection. And in FPGAs and other field-programmable devices, to permenantly set a topology of circuit or logic elements, by blowing fuses.
And in electrosurgery, you can fuse tissue, joining, like welding, albeit without the addition of the welding rod.
Name collision. Not uncommon, really.
And in electrosurgery, you can fuse tissue, joining, like welding, albeit without the addition of the welding rod.
Name collision. Not uncommon, really.
Network Analyzers
I'm probably the only person in the world who has used
a "network analyzer" in both senses:
In the modern digital networking sense, I've used Ethereal (now Wireshark) to look at IP packet contents. It shows bytes in a packet, parsed according to the various networking layers. EG a UDP packet might contain a command, and itself is wrapped in an IP header.
In the older analog sense, I've used an IC, the AD5933 which can analyze a LRC (inductor resistor capacitor) network. It sends a range of frequencies into a device and listens to the amplitude and phase of the output. Used to take a 100 lb box the size of a microwave oven; now its a chip.
This is what you get for being an eclectic engineer.
a "network analyzer" in both senses:
In the modern digital networking sense, I've used Ethereal (now Wireshark) to look at IP packet contents. It shows bytes in a packet, parsed according to the various networking layers. EG a UDP packet might contain a command, and itself is wrapped in an IP header.
In the older analog sense, I've used an IC, the AD5933 which can analyze a LRC (inductor resistor capacitor) network. It sends a range of frequencies into a device and listens to the amplitude and phase of the output. Used to take a 100 lb box the size of a microwave oven; now its a chip.
This is what you get for being an eclectic engineer.
04 May 2009
CSPAN fun
Watched Dan Kaminsky et al try to explain to some congresscritter Weiner
that the internet (upon which civilization is now built) is completely insecure.
Kaminsky was a surprisingly good speaker, only a few tech idiosyncracies slipped in "its a solve"), always using "software" for executables. He concentrated on DNSSEC which is a good idea but hardly sufficient. (The DNS cache poison hack is
Kaminsky's current claim to fame) It was clear at a couple of points that the congresscritter didn't get it, didn't understand the answer, or asked a nonsensical question.
Still, it was entertaining enough for me to watch.
that the internet (upon which civilization is now built) is completely insecure.
Kaminsky was a surprisingly good speaker, only a few tech idiosyncracies slipped in "its a solve"), always using "software" for executables. He concentrated on DNSSEC which is a good idea but hardly sufficient. (The DNS cache poison hack is
Kaminsky's current claim to fame) It was clear at a couple of points that the congresscritter didn't get it, didn't understand the answer, or asked a nonsensical question.
Still, it was entertaining enough for me to watch.
03 May 2009
Photography: Ridge Park trail rattlesnake
Ok, I said this was going to be for work, but this is pretty
cool, from yesterday
He was a very mellow reptile.
cool, from yesterday
He was a very mellow reptile.
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