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Comment PRCesque (Score 4, Insightful) 685

I don't want to live in China. Whether wikileaks is good, bad, right, wrong, or ugly, if we endorse the self-protectionist nature of the PRC govornment domestically and internationally, if we deny the truth in intellectualism in our graduate schools, then we have ourselves fearfully denied the truth of human nature to seek improvement through understanding and expansion through creativity.

That societies and the global community will have difficulty digesting the recent events does not mean that we shouldn't learn to cope with what is merely a more true revelation of where our mutual interests exist and where our relationships are perhaps thinner than we believe ourselves capable of addressing.

Comment Greatest Password Method Ever - Pass It On (Score 1) 563

Step 1: Make a sentence that's memorable, such as "I am making a password that I will never forget"
Step 2: Use title capitalization rules, such as Article Adjectives and Prepositions: the Capitals of Tomorrow.
Step 3: Convert to Acronym. Preserve capitalization.
Step 4: Convert at least a few letters to l33t.

Step 1: i'm telling you, it's easy to create strong passwords
Step 2: I'm Telling you, it's Easy to Create Strong Passwords
Step 3: ITyiEtCSP
Step 4: I'I'yiEtC5P

Randomness avoids dictionaries. Using conversion rules like these, you end up with something that has a meaningful basis, but looks quite random.

Comment King? Looks More Like the Clown (Score 2, Insightful) 207

Five important aspects of a mouse:
1 Frictionless Scroll Wheel (no bumps while rolling...carpal tunnel)
2 Buttons click with very little vibration. After several thousand clicks per day, the difference between Thwump and TwhaCkchkchck becomes painfully obvious
3 Very, very precise tracking. Although Blue-track is awesome on rough surfaces, I like that first pixel to be quantum mechanically entangled with the first detectable movement. Making users hands numb is not an acceptable way to bring tactile feedback and mouse movement into synch.
4 Shape. Just don't make it suck. Mechanically, I really like there to be troths for the fingers. I think they help bring more of the finger into contact and use the soft tissue to dampen vibrations quickly and gently. It also helps reduce the total moment carried by the fingertip because some of it is applied towards the base.
5 Transmitter and battery....afterthoughts but they need to be on a list that includes everything a mouse engineer should know.

When I started using blender to do tons of 3D modelling, compositing, skinning, animation etc etc, I noticed how crappy mice really are. Most seem to be designed so that oilfield workers will still feel comfortable using them after pulling several thousand feet of pipe.

When truly tied to lots of mouse action, the most important thing is to make it as much of a psychic experience as possible. The mouse should barely exist.

When the US Government Built Ultra-Safe Cars 520

Jalopnik has a piece on a mostly forgotten piece of automotive history: the US government built a fleet of ultra-safe cars in the 1970s. The "RSV" cars were designed to keep four passengers safe in a front or side collision at 50 mph (80 kph) — without seat belts — and they got 32 miles to the gallon. They had front and side airbags, anti-lock brakes, and gull-wing doors. Lorne Greene was hired to flack for the program. All this was quickly dismantled in the Reagan years, and in 1990 the mothballed cars were all destroyed, though two prototypes survived in private hands. "Then-NHTSA chief Jerry Curry [in 1990] contended the vehicles were obsolete, and that anyone who could have learned something from them had done so by then. Claybrook, the NHTSA chief who'd overseen the RSV cars through 1980, told Congress the destruction compared to the Nazis burning books. ... 'I thought they were intentionally destroying the evidence that you could do much better,' said [the manager of one of the vehicles' manufacturers]."

Comment Aerospace Engineer Angle (Score 5, Informative) 673

The cooling system used in gas turbines (jet engines) is very sophisticated and necessary to keep the superalloy blades from creeping too fast. The system consists of bypass air channeled through the blades and exhausted through tiny perforations, creating a layer of cooler air between the blade and the hot flow from the combustor. Furthermore there are two ceramic layers on the outside of the blade. One to prevent oxidation. One to slow heat transfer (insulate). As has been mentioned in other articles, the cooling pores could get clogged by the ash. I also suspect the coating might fail if impacted by ash. If the coating fails or otherwise reacts with the ash, then you can definitely have a problem.

If the blades get just a few tens of degrees hotter, they will surely fail. There's not a lot of margin for error with jet engines. Through good design and manufacturing control, we've managed to make gas turbines extremely reliable, but ash is not a design condition at all. It's abrasive, might react with the coating, and might accumulate on the blades, changing both their mass and aerodynamics.

Comment Re:Huh? (Score 1) 319

If detection is mostly reliable, tracking is difficult, and the speed is high, then interception is going to be almost impossible. For ballistic missiles we're talking about M > 10 flight. For any type of gun-system, we have to detect the incoming projectile at range, track it even if it's maneuvering, and both pinpoint the location and actuate the gun system with enough accuracy to get a hit. Although high speed projectiles or lasers will reduce the need for predicting the flight-path, the real issue is still going to be tracking a high speed low-observable warhead at sufficient range to shoot it while it's in the weapon's effective envelope. That time will get shorter and shorter against faster warheads. The accuracy of the system will be hard-pushed by low-observable to generate a good track at range while the guns will be hard-pressed to aim at shorter ranges where angular velocities will be higher.

The thing that's going to allow us to get out of the stealth vs detection engineering/technology cat & mouse game is a rarely (if ever) employed implementation of radar that uses wavelengths on the order of the vehicle being searched for. Once the wavelength size is about the size of the object, nothing is invisible to radar. The trouble is that this method can't produce sufficiently accurate information for interception.

However, once the general area of the target is known, it would be easily possible to get an interception vehicle within the vicinity of the flight path. Tracking at closer ranges affords more detection options and better accuracy. If we're going to do an intercept against supersonic and hypersonic targets with low-observable technology, it's going to take everything available when it comes to accuracy. We'll have to push really push sensor designs and squeeze out a lot better kinetic performance from the rockets.

I'm expecting a combination of stealth compromising radar, less easily defeated illumination technologies, and high performance intercept vehicles with robust sensor design working in tandem with ship-based high-power painting or even coordination with UAV's.

Even if it's not missile saturation attacks from long ranges (where at least we can detect the launches due to boost motor signature) there's still the issue of the inevitable stealth aircraft penetrating defenses and launching a saturation attack at short range. The aircraft would effectively be an efficient cruise stage for a package of small missiles that only need to boost for a supersonic dash into the target. Small missiles with relatively large warheads and little warning for intercept. In terms of aircraft and missile weight (and cost) it would be very effective.

Look at it this way, we can talk all day about how to protect open-water naval ships from saturation attacks with low-observable warheads, and it will usually work out okay if we start packing enough detection and interception firepower in the correctly sized area (most anti-ship missiles designed for saturation will communicate with each other and prioritize targets), but compare how much that will cost and how much hardware we will have dedicated just to giving us the ability to sit on the surface compared to making higher value targets (ahem, giant carriers that are already nuclear powered and will always and forever more be easy to target) less vulnerable to begin with. If we can put 100m of water in between us and ASBM's, that's a lot better margin for survival than if the interception vessels take hits and suddenly it's a defenseless carrier vs. ASBM saturation attack.

Comment Re:Huh? (Score 2, Informative) 319

It's a fundamental tracking problem between large and small targets. In order for ships to be reasonably well off sitting on the surface, they need to be able to track incoming warheads and shoot them down with missiles etc. Ships can be made low observable. Missiles can be made low observable. Ships can use gigantic phased array antennae. Missiles have less tracking power, but are looking for a bigger target. The ship might have an excellent radar, but it's trying to direct fire onto a small target.

Putting up a defense will require a lot of devices that, while possibly made small on radar/IR/visual, will still be additional vectors of detection. Couple all that with the possibility of passive terminal phase warheads, and surface ships will have to be constantly blasting away with their phased arrays. So much for low EM emissions.

The situation keeps looking worse as you start considering the possibility of saturation attacks with multi-warhead launch vehicles from long ranges at high speeds. Any defense mechanisms will eventually get overwhelmed. It's as easy as increasing the number of inbound warheads.

Navies can either try to go stealth and battle with the issue of hiding massive targets from increasingly cheap and effective sensors or they can put a little water in between themselves and what might be out there.

In terms of cost effectiveness, Naval vessels will fall behind missiles every time. Especially when you start looking at the cost of constructing small lines of ships in specially equipped dry-docks, like those used to build nuclear powered carriers. Mass-produced missiles packaged in sealed rounds on mobile launchers will drive carriers 3000km from the coast at one hundredth the cost of the carrier.

Few aircraft, and almost no carrier-born aircraft, have the capability to operate at that range without giving up all of their payload weight fraction. Either the Navy adapts to emerging threats fast or the US is going to be trying to negotiate foreign policy with billion dollar paper-weights.

Comment Re:Huh? (Score 1) 319

Hit the spot. For the payload and range, there's an obvious gap in the current capabilities in the US fleet and most of the world's armed forces. The Polaris example is a little bit overkill, as a Polaris can hit pretty much anywhere on the globe and VERY fast relative to any atmospheric flier. The range diagram works a bit like this:
Artillery ~20-30km with RAP etc
Supersonic Surface-skimming Rockets ~50-100km
Cruise Missiles ~1000km
Ballistic Missiles ~1500km-infinity

What you notice in this analysis is that all of the options are fast except the subsonic cruise missile. Currently, there are some very cool missiles out there like the MBDA Meteor and the ages old SA-6 etc which use integral rocket boosters to go supersonic and then use ducted-rockets to increase their specific impulse to equal or more than hydrogen rockets without any of the mechanical complexity. Very slick concept. These missiles can get around the inability of ram-rockets to provide static thrust and make good use of the volume taken up by the ram-rocket combustion chamber. It's one of those serendipitous design coincidences.

Count on seeing a lot of development in both shorter range ballistic missiles and super/hyper-sonic cruise missiles. Who wants to build fighters and carriers etc when you can just shotgun an enemy with cheap low-observable warheads at M > 1 speeds at any range you find convenient?

The world is headed towards a race to build the cheapest missiles and anti-missles that can fit on the cheapest ships and submarines. Big rockets with dual-burn solid motors and the large hulls for carrying large numbers of them will become a financial burden. We're going to see more and more focus on the ability to detect and intercept low-observable, low-emission warheads with the cheapest sensor that will get the job done.

The end result is probably more submersible vessels to avoid compulsory spamming anti-missile destroyers. The US Navy better get used to lying low. 100m below the surface and undetectable. A bunch of metal on the surface is going to increasingly be a liability. The generals won't like it, but there's a reason Kelly Johnson said "don't deal with the Navy." Grow up or cry about Chinese ASBM's. That's the future.

Comment Not a First - Re-Emerging Trend (Score 2, Interesting) 319

Russia built a series of supersonic anti-ship missiles with ranges in the cruise category. They were mostly fit aboard submarines and destroyers and designed for saturation attacks, which our missile defense systems were poorly equipped to deal with.

Using modern technology (higher temperature alloys, ceramic composites, and CFD optimization) it would be easily possible to build a cruise missile in the 1000nm range. In fact, because subsonic cruisers have to combat with launcher dimensions, their form factors are ill-suited for subsonic drag reduction and supersonic missiles might have an aerodynamic advantage.

ATK is currently developing a hypersonic cruise missile for the 800km range, which is an important gap filler between what artillery, short-range missiles, and ballistic missiles can hit quickly. This range is currently filled by subsonic cruise-missiles which can take over an hour to reach the target. Time-critical-strike it's called.

The issue with a supersonic cruise missile is that it needs even more than a subsonic cruiser to fly at high altitude in order to achieve satisfactory range. Aerodynamic heating is difficult, perhaps limiting at low altitudes for more than a short terminal phase. Flying at high altitude means they are easier to detect (not that look-down-shoot-down isn't standard, but ship-based phased-array radars won't be looking down) albeit harder to intercept due to their higher velocity.

What's really scary are the Chinese developed anti-ship ballistic missiles. Stealthy re-entry vehicles that can perform course changes. This is an interception nightmare and likely driving the US Navy ballistic.

Comment Sony Noise Canceling Kicks Ass (Score 0, Offtopic) 360

The older players used to have some weak/annoying DRM, but the newer ones give you the freedom you want when uploading tracks. I had a little 2GB older model that had an unbelievable battery life of like 50hrs.

One day I was walking by train tracks as a train was approaching. Just as I pressed play (~2s delay to start up on that model) the train's horn starts up. BWAAAAAAAAAAAAAAAAAAAAAA!!!aaaaaaaaaaaaaaaaaaaah..... That's the correctly capitalized onomatopoeia for a train against noise canceling earbuds. They're awesome.

Comment Oh the Burden of Soon to be Educated and Employed (Score 3, Insightful) 344

Lifeblood sucking students who contribute nothing to society and ruthlessly download music and movies must pay their toll just like all the rest of us hard working people with income. We all had spare change during school to throw at the municipal government. Why can't they?

And while we're at it, we need to tax other non-contributing members of society who place a burden on social services. I'm all for a tax on K-12 students, a tax on pre-schoolers, a tax on the disabled, senior citizens tax, and a tax on people who have crimes committed against them.

After all, with all the student financing available, they'll just pay it with loans right? So it's like we're actually taxing their future income!

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Almost anything derogatory you could say about today's software design would be accurate. -- K.E. Iverson