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cocoablazing

244 karma · joined February 17, 2015

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cocoablazing··on HSBC is killing my business, piece by piece 
Retail customers are the cheapest source of capital for BB. I remember directors would laugh about it when it was brought up. Banks are not doing retail (any) customers any favors.
cocoablazing··on Man Who Refused to Decrypt Hard Drives Still in Prison After Two Years
The hashes were acquired as Freenet content hash keys. He was sharing CP on freenet, which the government scrapes for known CP signatures.
cocoablazing··on Redesigning Python's named tuples
I would expect that construction to result in identical behavior for dict() and certainly not anything calling itself a tuple. NamedTuples behaving in the manner you expect violates LSP with respect to tuple().
cocoablazing··on We Fight for the Users
Social mores are social norms so widely/fervently held that they predicate the law itself, such as prohibiting incest. The term was invented to refer to these types of commonly held beliefs by a sociologist.
cocoablazing··on Show HN: An attempt to measure fermentation activity from the sound of bubbles
You are better off squaring the signal. Applying an FFT to get the magnitude will smear your signal in time. I suggest you look into acoustic emission detection.
cocoablazing··on Show HN: An attempt to measure fermentation activity from the sound of bubbles
Since bubbles popping are a random and impulsive source, the spectrum of the detected noise will be the resonance of the glass plus a white noise floor.

48khz is not overkill. Acoustic emission sensors used to detect signals like this typically use many times that sampling rate.

cocoablazing··on Hackers Are Targeting Nuclear Facilities, Homeland Security Dept. And F.B.I. Say
Non-safety-critical components in the steam plant are likely to have networked PLC control. While nuclear probabilistic safety assessments support that licensed reactors can safely endure casualties involving such components, the safety system is subject to failures and crippling the plant and causing a reactor transient is likely a good enough result.
cocoablazing··on The Workings of an Ancient Nuclear Reactor (2009)
Our sun can't come close to the temperature reached in advanced fusion weapons, and it exhibits the power density of a compost pile.

8/10

cocoablazing··on Estimating a nuclear blast with bits of paper
The thermal radiation and resulting firestorm would be the cause of most deaths from an attack on a city.
cocoablazing··on China's new submarine engine
Large vessels use much more complex and specialized axial thrust bearings for propulsion shaft loads. What works for an ROV won't necessarily do the job at the required scale.
cocoablazing··on Estimating a nuclear blast with bits of paper
The shock wave is a serious hazard to personnel far beyond the fireball. Just a few pounds of dynamic overpressure presents a hurricane-force wind hazard, and five will result in catastrophic damage to non-hardened structures and a near complete loss of life. The shock front detaches quite early from the fireball. The classic scary videos of residential structures annihilated during nuclear testing were sampled from beyond the maximum fireball radii.
cocoablazing··on China's new submarine engine
If the impeller is capable of developing sufficient force to move a submarine at operational speeds, it will require serious axial thrust bearings.

The impeller pushes against the housing with the same force that a conventional shaft develops against a shaft-mounted axial thrust bearing would for the same speed and vessel geometry.

cocoablazing··on Ask HN: Books you wish you had read earlier?
Myth is certainly not science. Transmission of belief occurs through myths, not knowledge.
cocoablazing··on Python For Finance: Algorithmic Trading
You are painting with an extremely broad brush. Before you give up on this idea, just try this exercise: enumerate the markets and financial instruments that you could potentially trade in, and characterize the current trading environment in that market.

An ultra-HFT liquidity provider being profitable has little bearing on the potential profitability of quantitative trading on significantly larger timescales. There isn't sufficient volatility in most products for these actors to eat the lunch of actors who have alpha on trades that can hold for significant periods.

cocoablazing··on The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance
The PS2, Xbox 360, Wii, and some intel chips with iris provide on-die DRAM caches.
cocoablazing··on Parallel Python
Still, multiprocessing objects like Array and Manager are limited to ctypes.
cocoablazing··on US Navy Nuclear Power School Study Materials
The NNPP doesn't distribute any high quality theoretical nuclear engineering texts. The good texts they use are targeted towards the specific systems and materials deployed on ships and submarines.
cocoablazing··on Has There Been a Nuclear Incident in the Arctic?
This could also be leakage from peaceful isotopic production operations, which are and will be a persistent source of false positives for the global iodine detection system.
cocoablazing··on Has There Been a Nuclear Incident in the Arctic?
You need a concentrating system and a spectroscopic radiation measurement system to produce a signal with sufficient SNR.
cocoablazing··on Has There Been a Nuclear Incident in the Arctic?
If a warhead fizzled, it would have destroyed the submarine carrying it, which would have detonated hundreds of tons of rocket fuel and the rest of the explosives on board. We would have known about the explosion the same way we did the Kursk.
cocoablazing··on The Murky Future of Nuclear Power in the United States
This reactor was 1/50th the scale of a typical power reactor. The radiation, thermal-hydraulic, and chemical environment of a full-scale reactor is different. Different stress corrosion interactions, severe oscillating stresses due to thermal-hydraulic fluctuations at assembly outlets... The operational record of such reactors hardly supports them as foolproof or economical versus the best modern water reactors.
cocoablazing··on The Chernobyl Story in pictures
Chernobyl occurred prior to the warming in relations that resulted from Gorbachev's reforms, so it is understandable that the Soviets perceived a significant threat from admitting the accident occurred. Unlike Fukushima, Chernobyl slowly released radioactivity for days due to the fire. Initial Soviet assessments of the accident severity were optimistic. I'm not saying that they were right in delaying, but the fire was still burning and the atmospheric release ongoing when they publicly revealed it.
cocoablazing··on How an 89-year-old cold warrior became America’s nuclear conscience
Two serious fallacies here: 1) The risk posed by nuclear war is correlated across nearly every individual, so the odds ratio between risks posed to you as an individual and nuclear war is of no use to the practice of risk management in such policy matters. 2) You are comparing the study of things entirely outside our control (volcanos), and potential doom which is entirely of our own making, towards the end of maintaining control by holding the world under the constant threat of annihilation.
cocoablazing··on Hedge Fund Math: Heads We Win, Tails You Lose
Compensating for this effect of training may be done by properly discounting the measure using the Deflated Sharpe Ratio or similar corrected SR's. I always ask any interviewee who cites experience producing these measures a question with this effect as the crux. Few come back with a correct answer.
cocoablazing··on Nuclear Plant Accidents: Sodium Reactor Experiment
Nuclear electric power production carries risks, which are outweighed by the expectations of lives saved by reducing air pollution and greenhouse gas production.
cocoablazing··on Russia's improved ballistic missiles to be tested as asteroid killers
TTAPS assumed strikes on petroleum facilities and cities. I don't think your scenario fits the assumptions of any study on nuclear winter.
cocoablazing··on Russia's improved ballistic missiles to be tested as asteroid killers
Every statement in here is wrong, but the greatest error is this: the most potent leg of the US triad is invulnerable to the threat you describe, and is capable of annihilating the USSR. Yes, US SSBN's are equipped with time-travel technology to destroy the Russian arsenal before its designers were even born.
cocoablazing··on Russia's improved ballistic missiles to be tested as asteroid killers
The United States continues to invest billions of dollars in advancing nuclear weapons science (NIF,ASCI,LEP). A critical detonation of a weapon is unnecessary. There is plenty of useful data available from a long-term program such as NIF, which DOE uses to refine physical simulations of weapons phenomena.
cocoablazing··on Russia's improved ballistic missiles to be tested as asteroid killers
That relation is equivalent to conservation of mass, and wouldn't account for any energy losses. As the asteroid is fragmented, its total cross section rises, increasing energy deposition in the atmosphere, reducing available energy for ejecta.

WRT to arms-control regimes: What's the difference between an asteroid-killing BM and an ICBM? Only the warhead count. START inspectors would count such a launcher toward the cap.

cocoablazing··on What 50,000 watts of RF energy sounds like through a jumper cable
The skin effect should result in a high-frequency AC current propagating at lower tissue depths than a lower-frequency AC current. Why would RF AC propagating in flesh not follow this general rule?
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