Not an Elephant Rifle

Saturday, June 20th, 2009

Alan James of the Rhodesian African Rifles came across an elephant that had stepped on a land mine. When he went to put the poor beast out of its misery, the experienced elephant hunter was reminded that his FN FAL assault rifle was not an elephant rifle:

James had to empty the best part of a 30-round magazine into the unfortunate creature before it collapsed to the ground.

The FN FAL fires a powerful 7.62x51mm NATO round — what American hunters call a .308 — which is much bigger and more powerful than a 5.56mm (.223) round from an M16 — but nowhere near as big and powerful as a .577 Nitro Express elephant round.

(From Tools of Violence by Chris McNab and Hunter Keeter.)

The Three Laws of Thermodynamics

Saturday, June 20th, 2009

The Three Laws of Thermodynamics are fundamentally downers:

  1. Energy can neither be created nor destroyed. It can only change forms.
  2. The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.
  3. As temperature approaches absolute zero, the entropy of a system approaches a constant minimum.

It can help to put them in joke form:

  1. You can’t win, you can only break even.
  2. You can only break even at absolute zero.
  3. You can never reach absolute zero.

Semi-Auto or Full-Auto?

Thursday, June 18th, 2009

If you’re armed with a modern assault rifle, which can fire in semi-auto — one shot per pull of the trigger — or full-auto — like a machine-gun — when, if ever, should you shoot just one shot at a time?

A series of 1968 studies by the US Army concluded that semi-automatic and automatic fire produce different hit ratios at different ranges within a set time period.

Surprisingly, at more than 50m but within comfortable visual range, semi-automatic aimed fire gave the most target hits. The semi-auto mode encourages aimed shooting while, as we have already observed, the muzzle-shuddering characteristics of full-auto fire tend to throw off the aim.

Below 25m, however, full-auto fire produced more hits, reflecting the fact that at close range a single swept burst was likely to include multiple hits.

Beyond comfortable visual range (say above 800m), and excluding professional sniping, full-auto machine-gun fire gave the greatest likelihood of target strike, this creating a generally destructive “beaten zone” (the elliptical pattern on the ground where the bullets strike) in which a target was unlikely to survive unscathed.

Furthermore, between 50 and 300m semi-auto fire was always the quicker in terms of time elapsing from first pull of the trigger to a target hit, proving that at practical combat ranges well-aimed fire is generally the most effective, even if it uses fewer rounds than full-auto fire.

Common Misconceptions about Space Travel

Thursday, June 18th, 2009

A “nearly wise” science-fiction fan has compiled this list of common misconceptions about space travel — some obvious, some not, some grammatical, some not:

  • Space is not an ocean. In particular, space is not two-dimensional, there is no friction in space, and spacecraft will not have their decks laid out as if they were seagoing vessels.
  • Space is three dimensional. Spacecraft are not limited to moving on a surface like a boat, they can go “up” and “down.” They are not even limited like a aircraft, the latter is limited to how far up and down they can go. A spacecraft can theoretically fly to infinity in any given direction.

    There is no limit on their orientation either. If you saw the Starship Enterprise approaching the Starship Intrepid and one was “upside down” with respect to another, you might think this was wrong but in reality there is nothing preventing this. Even worse: the nose of the other spacecraft might not even be pointed in the direction the ship is flying.

  • Rockets are not boats. With a scientifically accurate rocket, the direction of “down” will be in the same direction that the rocket exhaust is shooting. In other words, a spacecraft will have the general internal arrangement of a skyscraper, not that of a passenger airplane.
  • Rockets are not fighter planes. It is impossible to make swooping maneuvers without an atmosphere and wings.
  • Rockets are not arrows. Spacecraft do not necessarily travel in the direction their nose is pointing.
  • Rockets got wings. If your rocket has a multi-megawatt power plant, an absurdly high thrust thermal rocket propulsion system, or directed energy weapons it will need huge heat radiators to purge all the waste heat. Otherwise the rocket will melt or even vaporize. Radiators look like large wings or arrays of panels. The necessity of radiators a real problem for warships since radiators are pathetically vulnerable to hostile weapons fire.
  • Rockets don’t got windows. Spacecraft have no need of windows or portholes, for much the same reason as a submarine.
  • There is no friction in space. In space, if a ship turns off its engines it will maintain its current velocity for the rest of eternity (unless is crashes into a planet or something).

    Acceleration and deceleration are symmetrical. This means if your spacecraft spends an hour accelerating to a speed of 1000 meters per second, it is going to take roughly another hour to decelerate to a stop. You cannot “put on the brakes” and suddenly stop, like you can do with a boat or an automobile. (I say “roughly” because as you accelerate your ship looses mass due to expending reaction mass, so it becomes easier to decelerate. But this is a complicating detail you can ignore for now)

  • Fuel is not propellent. Mass is violently thrown away in the form of the rocket’s exhaust and the reaction accelerates the rocket forward. This mass is of course the “reaction mass.” It is sometimes also called “remass” or “propellant.”

    The “fuel” is what is burned or whatever to generated the energy to expel the reaction mass. For example, in a classic atomic rocket, the fuel is the uranium-235 rods in the nuclear reactor, the reaction mass is the hydrogen gas heated in the reactor and expelled from the exhaust nozzle.

    There are only a few confusing cases where the fuel and the reaction mass are the same thing. This is the case with chemical rockets such as the Space Shuttle and the Saturn 5, which is how the misconception started in the first place.

  • There ain’t no stealth in space. In space, there is no practical way to hide your military spacecraft from detection by the enemy.
  • There is no sound in space. There is no air in space so neither is there sound.
  • Mass is not weight. The Space Shuttle may be floating next to the station with a weight of zero, but it still has a mass of 90 metric tons. If it is stationary and you pushed on it, there will be very little effect.
  • Free fall is not zero gravity. Technically, people in, say, the Space Station are not in “zero gravity.” The gravity at the altitude of the Station is about as strong as it is on Terra’s surface (it is about 93% of full gravity). The reason that everybody floats around is because they are in a state of “free fall.” If you were in an elevator, and the cable snapped, you too would be in a state of free fall and would float around. At least until you hit.
  • No vacuum pops. And if you were suddenly thrown into the vacuum of space without a spacesuit, you would not pop like a balloon.
  • They don’t want our water. Aliens invading Terra to steal our water makes about as much sense as Eskimos invading Central America to steal their ice. Water is one of the most common substances “out there.”

Common skin cancer drug smoothes wrinkles

Thursday, June 18th, 2009

Dr. Dana Sachs of the University of Michigan has found that Efudex (fluorouracil), which is normally used to treat scaly or crusty pre-cancerous bumps on the skin called actinic keratoses, also smoothes ordinary wrinkles — but not painlessly:

“Patients look really bad,” Sachs said in a telephone interview. “Their skin is red. I’ve heard people describe it as looking like raw hamburger meat.”

But after the treatment, patients have said their skin looks younger. “People have commented for years that they look better. Not only are their pre-cancers gone but the quality of their skin seems to be improved,” Sachs said.

Sachs and colleagues wanted to see if they could actually measure a difference in the appearance of skin.

They studied 21 people aged 56 to 85 with actinic keratoses and sun damage. The volunteers used the cream twice daily on the face for two weeks and the team measured changes in the skin, taking facial biopsies over a six-month period.

The drug had a significant effect.

“People’s skin was much softer,” Sachs said. “The texture was improved. There are fewer wrinkles around the upper cheek and eyes.”

The researchers also noticed skin appeared less yellow and more even toned with fewer brown spots.

Sachs said for patients with precancerous spots, the findings may be an added inducement to finish treatment. It may be useful at treating the signs of sun damage in other patients as well, she said.

The Ins-N-Outs of Lean

Thursday, June 18th, 2009

Bill Waddell explains what he has gleaned of the Ins-N-Outs of the lean production of a not-so-lean product:

Check out the menu:

That’s it — no kids menu, no breakfast menu, no salads, chicken, fish, no low calorie, no diet anything — just very, very good burgers.

The burgers come from their own butcher operation in California, and the buns come from their own baking plant. The potatoes are peeled, sliced and cooked in the restaurant fresh. They are about as vertically integrated as a business can be.

Their employees make a buck an hour or more over the pay scale of the competition, and they participate in a 401K

In-N-Out Burger makes a lot of money.

So what are the lean lessons?

Focus – these people know what business they are in and they concentrate everything on it

Simplicity – they don’t try to be all things to all potential customers. They have quite obviously rejected the old Alfred Sloan “A car for every purse and purpose” mantra, and have followed a simple model much more akin to Toyota’s

Long term thinking – they grow at a steady snail’s pace and keep it under control. The aim is obviously sustainable profits. They have about 230 stores and only recently have slowly spread from California into the neighboring states of Arizona, Nevada and Utah. No franchises — everything is company owned and controlled.

Control of the critical elements of the product – They are in the hamburger business and they maintain absolute control over everything that goes into it.

By avoiding the lure of offering a lot of things around the edges of their core business, they achieve a cost structure much better than McDonalds or Burger King. No floor space, inventory and maintenance costs are wasted on all of the resources needed to support peripheral products. The priority they put on people and quality is what makes waiting in those long lines worth the customers’ while.

The owners of In-N-Out Burger are a great example of the folly of thinking that ‘innovation’ is a strategic imperative. Being the very best at the core product of the business is the key to success. They also demonstrate that outsourcing and keeping labor cost low doesn’t equal success either.

The Nuclear and Non-Nuclear EMP Threat

Thursday, June 18th, 2009

Tom Harris explains the nuclear EMP threat — and how researchers discovered it largely by accident:

In 1958, American tests of hydrogen bombs yielded some surprising results. A test blast over the Pacific Ocean ended up blowing out streetlights in parts of Hawaii, hundreds of miles away. The blast even disrupted radio equipment as far away as Australia.

Researchers concluded that the electrical disturbance was due to the Compton effect, theorized by physicist Arthur Compton in 1925. Compton’s assertion was that photons of electromagnetic energy could knock loose electrons from atoms with low atomic numbers. In the 1958 test, researchers concluded, the photons from the blast’s intense gamma radiation knocked a large number of electrons free from oxygen and nitrogen atoms in the atmosphere. This flood of electrons interacted with the Earth’s magnetic field to create a fluctuating electric current, which induced a powerful magnetic field. The resulting electromagnetic pulse induced intense electrical currents in conductive materials over a wide area.

You don’t need to detonate a nuclear weapon in the atmosphere though. You can instead detonate a non-nuclear flux compression generator bomb — which, really, sounds like something straight out of a bad sci-fi show:

The bomb consists of a metal cylinder (called the armature), which is surrounded by a coil of wire (the stator winding). The armature cylinder is filled with high explosive, and a sturdy jacket surrounds the entire device. The stator winding and the armature cylinder are separated by empty space. The bomb also has a power source, such as a bank of capacitors, which can be connected to the stator.

  • A switch connects the capacitors to the stator, sending an electrical current through the wires. This generates an intense magnetic field.
  • A fuze mechanism ignites the explosive material. The explosion travels as a wave through the middle of the armature cylinder.
  • As the explosion makes its way through the cylinder, the cylinder comes in contact with the stator winding. This creates a short circuit, cutting the stator off from its power supply.
  • The moving short circuit compresses the magnetic field, generating an intense electromagnetic burst.

Re-Engineering the Earth

Thursday, June 18th, 2009

I get the feeling that Graeme Wood is not a fan of re-engineering the Earth:

If we were transported forward in time, to an Earth ravaged by catastrophic climate change, we might see long, delicate strands of fire hose stretching into the sky, like spaghetti, attached to zeppelins hovering 65,000 feet in the air. Factories on the ground would pump 10 kilos of sulfur dioxide up through those hoses every second. And at the top, the hoses would cough a sulfurous pall into the sky. At sunset on some parts of the planet, these puffs of aerosolized pollutant would glow a dramatic red, like the skies in Blade Runner. During the day, they would shield the planet from the sun’s full force, keeping temperatures cool—as long as the puffing never ceased.

The artist’s depiction looks more Sky Captain than Blade Runner. I guess airships scream pulp more than noir.

Tools of Violence

Wednesday, June 17th, 2009

I love the introduction to Tools of Violence:

Any book that focuses its entire subject matter on weapons skates on thin moral ice. There are two temptations, the first of which could be labeled “data worship.” Weapons are, for the most part, works of extremely advanced engineering that have a technical allure all of their own. Because of the extremity of the job they perform, they produce compelling facts and figures, ranging from muzzle velocities to explosive force, and these, when combined with the startling light and sound of their usage, can lead some to treat them with the same wide-eyed fascination as cars or space rockets, with lots of potential for dramatic trivia.

For instance, eating a large chocolate bar actually generates the same energy output as that created by propellant detonating behind a 105mm field artillery shell, the key difference being that the energy of the artillery shell is released in a few milliseconds, not over half an hour or so. For large chunks of the world’s population, principally male, that is a fascinating fact.

Touché, Tools of Violence. Touché.

Space Navies

Wednesday, June 17th, 2009

A few years ago Steven Den Beste remarked that the characteristics of ships and their weapons have always dictated naval strategy and tactics, but science-fictional space ship battles are unsatisfying because the characteristics of space ships and their weapons don’t seem to dictate space strategy and tactics.

When I first read his essay, I hadn’t read much “hard” science fiction — I still haven’t, really — so I was largely unaware of the simple notion that there ain’t no stealth in space. In the vacuum of space, any ship with a crew is a 290-Kelvin flare. With its engines running, it’ll be hard to miss from even further away — and it will continue on a perfectly predictable trajectory until it fires those engines again. In fact, by comparing the energy given off by the engines to the ship’s acceleration, observers can even deduce the ship’s mass — and thus whether it’s a real ship or a decoy.

All this talk of infrared radiation brings up another point: space ships need enormous, vulnerable radiators. There are only three ways of getting rid of heat — convection, conduction, and radiation — and the first two don’t work in a vacuum. Yes, the vacuum of space is cold — but not because it’s full of cold matter. Without enormous radiators, any ship running its engines should melt in minutes.

So, our space ships trivially spot one another at enormous distances, following perfectly predictable trajectories. Each ship is vulnerable to a simple gun shot, unless it expends tremendous delta-V to change trajectory — putting itself on a new, perfectly predictable trajectory.

Ships probably won’t shoot simple unguided projectiles though; they’ll shoot guided missiles, which should be impossible to out-accelerate and dodge.

But you don’t have to dodge a missile if you can destroy it with point-defense lasers. It’s hard to say how easy that will be, but another alternative is to fry its electronics with a microwave laser, or maser, turning it into an unguided projectile, which can be dodged.

It’s not much like WWII in space.

What would happen after an EMP attack?

Wednesday, June 17th, 2009

A single nuclear weapon detonated a few hundred miles above the US could blanket the entire nation with an electromagnetic pulse that would disable most electronics. What would happen after an EMP attack?

Unless you are in a jet liner, plummeting to earth, or caught in a massive traffic jam of stalled vehicles on the interstate, you might not even know anything has changed. Sure the power is off, but we’ve all been through that dozens of times. You call the power company. But the phone doesn’t work and that might be slightly more unnerving. You might go to your car to drive around and see what happened and then it becomes more unnerving when the car does not even turn over, nor any other car in your neighborhood.

Twelve hours later the food in your freezer starts to thaw, if it is winter and you don’t have a wood stove the frost will start to penetrate in to your house, if summer and you live in Florida your house will be an oven. And that will just be the start.

Law enforcement will be powerless without radios, cell phones, and squad cars, unable to know where there is a crisis and how to react. The real horror show within hours will be in hospitals and nursing homes. They’re required by law to have back up generators, but those generators are “hot wired” into the building so power can instantly kick in if the main system shuts down. That “hot wiring” means the Electro Magnetic Pulse will take out the generators and their circuitry as well.

If you are familiar with what happened in New Orleans after Katrina, multiply that ten thousand times over to every hospital and nursing home in America. Nearly everyone dependent on life support equipment in ICUs will be dead within hours. Nearly everyone in nursing homes dependent on oxygen generators, respirators, etc., will be dead or dying while depending on the time of year temperatures within plummet or soar.

As to medical supplies, not just in hospitals but across the nation to every local pharmacy, they are all dependent on something called Fed Ex. As we have perfected a remarkable system of instant delivery, guided by computers, local inventories have dropped to be more cost efficient and even for reasons of security with controlled substances, which to ordinary citizens means pain killers. Supplies will run out in a matter of days. Those of us dependent on medications to control asthma, heart disease, diabetes, and a host of other aliments which a hundred years ago would have killed us shortly after the onset. . .will now face death within days or weeks, unless the national power grid comes back on line quickly and order is restored.

How long would it take to bounce back though?

Well, you see, we might not bounce back:

Any of us who have lived through a major disaster such as a hurricane, ice storm, or tornado, and then gone several days without power know the sequence, h ow much longer the wait seems to be, and then finally the welcome sight of a power company repair truck turning on to your block. . .and that truck might be from a power company five hundred miles away. All our disasters have ultimately been local in nature, Andrew in Florida, Katrina in Louisiana and Mississippi or one this author went through with Ivan in North Carolina. The disaster is local, even if fifty thousand square miles are affected, help streaming in from neighboring states, caravans of power trucks, each carrying not just experienced crews, but ladened down with all the replacement parts necessary to put electricity and phone service back into your house. When Ivan hit my town, dumping 30 inches of rain, wiping out the power grid and water supply, in less than twelve hours thousands of gallons of bottled water had arrived from Charlotte, power companies from Alabama, Tennessee and Virginia were arriving, the special parts needed to replace my town’s shattered water main from the reservoir were air lifted in by a national guard unit.

Consider though if the entire nation is “down.” Quite simply there are not enough replacement parts in the entire nation to even remotely begin the retro-fitting and replacement of all components. Every community will be on its own, struggling to rebuild … on their own.

Forget SAP, Run Down to Staples

Wednesday, June 17th, 2009

Kevin Meyer says you should forget SAP and just run down to Staples:

First get some people together and go through a value stream mapping exercise. Nothing fancy… just figure out what you’re currently doing. Take a few hours to think about it, to identify non-value-added activities, and kill those wasteful activities.

Next, run down to Staples. Buy a nice big whiteboard. While you’re there, pick up a some markers and erasers, a webcam, and a copy of QuickBooks (Manufacturing Edition). Grab some pizza for your team to celebrate their accomplishment (and a keg of beer if your HR group hasn’t tied you up in your underwear yet).

Back at the plant, mount the whiteboard on the shop floor where it will see the most traffic. Draw the flowchart on it. As a lean company you want to pull jobs from customer orders, so think about how the chart flows. Put little labeled magnet tags on the flowchart to indicate jobs. Remember to include your suppliers so you can trigger raw material orders. Get everyone on the shopfloor together and explain this visual method, and how it is everyone’s responsibility to manage the board.

Now take the webcam and aim it at the board and connect it to the company’s network so anyone, such as sales and customer service, can remotely view the board at any time to see the status of any job. Take your copy of QuickBooks, spend a couple hours setting it up, create a couple of user accounts for shipping and receiving people (of course receiving is done right to the point of use on the shop floor…).

Cost? A couple grand… maybe.

Does Personality Matter? Compared to What?

Wednesday, June 17th, 2009

Does Personality Matter? Compared to What?

According to [the meta-analysis in "The Power of Personality: The Comparative Validity of Personality Traits, Socioeconomic Status, and Cognitive Ability for Predicting Important Life Outcomes"], you can measure personality with a simple survey, then use it years or decades later to make good predictions about mortality, divorce, and occupational status.

The paper ends with three key graphs. The first shows correlations between mortality and (a) socioeconomic status, (b) IQ, and (c) four of the Big 5 personality traits:

As Caplan points out, The Bell Curve demonstrates that IQ out-predicts socioeconomic status, but apparently conscientiousness alone out-predicts IQ — at least with respect to mortality.

Are theses small correlation coefficients meaningful though? Compared to what?

Walter Mischel (1968) argued that personality traits had limited utility in predicting behavior because their correlational upper limit appeared to be about .30. Subsequently, this .30 value became derided as the ”personality coefficient.” …

Should personality psychologists be apologetic for their modest validity coefficients? Apparently not, according to Meyer and his colleagues (Meyer et al., 2001), who did psychological science a service by tabling the effect sizes for a wide variety of psychological investigations and placing them side-by-side with comparable effect sizes from medicine and everyday life. These investigators made several important points. First, the modal effect size on a correlational scale for psychology as a whole is between .10 and .40, including that seen in experimental investigations… Second, the very largest effects for any variables in psychology are in the .50 to .60 range, and these are quite rare (e.g., the effect of increasing age on declining speed of information processing in adults). Third, effect sizes for assessment measures and therapeutic interventions in psychology are similar to those found in medicine. It is sobering to see that the effect sizes for many medical interventions — like consuming aspirin to treat heart disease or using chemotherapy to treat breast cancer — translate into correlations of .02 or .03.

The development of mine warfare

Tuesday, June 16th, 2009

The cannon came into its own at the Battle of Lepanto in 1571, when the European Holy League — wonderful name, by the way — destroyed the Ottoman navy. Fourteen years later, an Italian engineer in the employ of the Dutch — named Frederico Gianibelli or Federigo Giambelli; spelling was flexible then — developed a mine, or, more poetically, a hellburner:

In 1585, Gianibelli was lving in Amsterdam in the Spanish Netherlands. The city was in the midst of a siege by Spanish forces under the Duke of Parma. The Duke blockaded the city by building a 2,400-foot wooden bridge across the Scheldt River, which effectively blocked off the city’s access to the sea and to English reinforcements. Destroying the bridge would be complicated. Half of the bridge rested on piles and the other half on boats that were chained together.

Gianibelli hit on the idea of sending a fleet of ships filled with explosives to blow up the bridge. The local government proved unconvinced by his plan and limited his resources to two exploding ships and 32 small fireboats. Gianibelli’s plan was to fill the holds of two exploding ships, Fortune and Hope, with 7000 pounds of gunpowder each. Fortune was armed with a slow burning fuse and Hope with a clockwork timer, both designed so that the ships would explode when they arrived at the bridge. On top of each ship’s hold, he placed a six-foot-deep layer of tombstones that he covered with “a pyramid, made of heavy marble slabs.” He filled the inside of the pyramid with mill stones, cannon balls, and various other metal and stone objects. The debris on top of the ship helped maximize the force of the explosion by directing the charge toward the bridge, though it is uncertain whether Gianibelli knew that it would do that. It also became lethal fragments flying through the air, cutting down hundreds of Spanish soldiers, which is likely why Gianibelli intended it to do.

The fireboats arrived at the rafts supporting the bridge first. Most became entangled in the hooks and spearheads of the bridge’s defenses or simply ran aground. The failure of these boats to cause any real damage drew cries of derision from the Spaniards on the bridge. The exploding ships followed shortly and drew up against the side of the bridge. The Fortune was the first to arrive. A small explosion was heard, but it produced no damage to either ship or bridge. A group of Spanish soldiers boarded the vessel and put out the few small fires they found. The party quickly left the ship.

The Hope arrived shortly, coming to rest near the juncture of the stationary and floating sections of the bridge. Smoke trailed upwards from small fires on the deck of the ship. The Duke ordered a group of soldiers aboard to investigate and watched from nearby as the men explored the ship. Somehow sensing trouble, a young ensign named De Vega managed with great effort to convince the Duke to move away from the ship. Moments after the Duke left, the clockwork timer on Hope detonated, blowing a 200-foot hold in the bridge and killing between 800 and 1000 Spaniards.

In the end, however, the commander of the Dutch naval forces, Admiral Jacobzoon, failed to take advantage of the breech, and Spaniards were able to repair the bridge during the night.

Harmonic Fluids

Tuesday, June 16th, 2009

Changxi Zheng and Doug L. James present a physically based algorithm for synthesizing fluid sounds, such as splashing and pouring: