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Comment: Equation for this answer (Score 2, Insightful) 397

by Grendol (#41318145) Attached to: Ask Slashdot: How Much Is a Fun Job Worth?
Back when I was working on an MSEE degree, my professor enlightened me to a simple equation to help compare happiness.

Happiness = (Location) x (Pay) x (entertainment value or pleasantness of what you are doing)

try to normalize all inputs to a scale of 0 to 2, yielding a result ranging from 0 to 8. You will quickly see that any one thing can kill the whole deal (multiplying by 0 tends to do that), and that some things can only compensate for inadequacies to a limited extent. So... in a practical sense, this quantitative answer to such qualitative things as job pay, location, and how much you like what you are doing, might help make the analysis comparison easier. Tweaking this to fit your specific situation makes all the sense in the world. Good Luck!

Comment: Clarity (Score 4, Informative) 429

by Grendol (#40758745) Attached to: Would You Trust an 80-Year-Old Nuclear Reactor?
Often, discussions about nuclear energy tend to run rampant with misinformation and hyperbole. I offer the following points for clarity, context, and thought.

1) Just to be clear: There are NO 80 year old reactors. If Chicago-Pile 1 was still operating, it would turn 70 this year. The oldest currently operating nuclear reactor is the Oyster Creek facility. This reactor came online December 23rd 1969 making it 42 years old curerntly. This is according to Wikipedia.

2) All NRC regulated reactors have maintenance performed on the systems every outage, to the point that much of the facility is newer than the day it turned on. This is due to maintenance and repair activity, as well as upgrades to improve efficiency. The article calls this "midlife refurbishment". The industry does this because it is easier and less costly than a new reactor. The thought process of the industry is that it is easier to tear down and rebuild under the existing license than it is to get approval for a new license. If the industry could feasibly replace a reactor vessel, I would bet they would.

3) ASME Boiler and Pressure Vessel Code Section 3 is a good code. Creep, Fatigue, Corrosion, and many other issues are addressed in this code that the non-nuclear codes for B&PV only tough upon exotic need, and then refer the engineer to the section 3 code. I encourage you to read it.

4) Some reactor operators send material samples to the Advanced Test Reactor at the INL for accelerated radiation age testing. This information is sought by the reactor operators to gain a better understanding for themselves about their own equipment.

5) Reactors are designed for a much longer life than 40 years, but the NRC set the 40 year license to force a mid-life review. Reactors get far better treatment than any car or plane that most people have ever have ridden in. In this context, a 40 year old reactor properly maintained is very possibly not a safety concern.

6) The Davis-Besse RPV head mentioned by the article was a case of criminal conduct in the eyes of some people, and is not considered normal operating behavior by people I have met from the industry. Whatever the facts are, the indictment can be found here.

7) Reactors designed to operated under the NRC have a "defense in depth" safety approach. The reactor and facilities are given a design basis accident that is a conservative forecasting of potential accident scenarios.

8) The NRC has a glossary available to you note the term "meltdown" is not there. Many people associated with the nuclear field feel that it is a poor term that does not adequately describe a problem's behavior or severity. This is borne out of the use of the term for several reactor failures that all had different designs, behaviors, and severity of failure.

9) New reactor designs offer some stimulating improvements. The Generation 4 reactor effort can be found at currently the US is operating Gen 2 reactors.

Comment: Re:It might be worse than that. . . (Score 2) 234

by Grendol (#36078018) Attached to: Chain Reactions Reignited At Fukushima

"The decay heat, which is 7% of 1000 MW"

IIRC, the reactors were 1000MW *electrical* output. Because of thermal efficiencies of steam generators of around 35%, I believe that means the thermal output of each reactor would have been about 1000/.35 ~= 2800 MW thermal energy.

So, instead of 7% of 1000MW = 70MW, I think you're looking at 7% of 2800 = 196MW.

That's a LOT of heat to get rid of, even if it is a small percentage of the 2800MW full output. shows the plant #2 at 784MW for electrical power out.

Assuming 30% thermal efficiency (35% seems high for a 1973 reactor, but I am guessing honestly), then the full thermal load would be ~2600 MW. 7% of that would be 183MW. So, you aren't too far off.

Not sure what the water volume of the reactor would be, but if you ever have a hard time falling asleep the NRC has the standards for a BWR/4 reactor (plant #2) at this site Note that page 1.1-5 talks about the RTP (Rated Thermal Power) of the heat transfer of the core to the coolant being 2436MW. Admittedly this is a US document but GE (the reactor designer) has usually made a point to support customer upgrades to US-NRC standards.

then you could figure the boil off rate assuming the 7% was unchanging (which it isn't, right off hand I don't recall the reported decay rate of that level). Truth is, 12 days later this won't even be close to 7% thermal load. 12 days later put the amount of Iodine through about 1.5 half lives so there would be much less Iodine left. Obviously other decay product would be on their own schedule. So, one might argue that the measurements show a restart, but if there was one, it is highly likely that it was a small localized one.

The physical laws do not lie or change, but I and others have been known to make errors in measurements and observations.

aside from this speculation of what went on based on the measurements they claim to have made.....

I find all this discusion about oceanic releases interesting since there are 5 USSR nuclear subs (3 of which had 2 reactors each), 2 US subs (with one 5SW reactor each) and one of the original 3 cores of the Lenin nuclear ice breaker all sunk in the ocean. Many of these 11 sunken reactors are in the Atlantic some up north nearer Russia, partially spent fuel and all.

Due to the US Department Of Defense plutonium breeding activities at the Hanford Nuclear Facilities many millions of curies were released into the Columbia River by primary coolant water used in the reactors there.

then there is the release made by coal plants which according to this article is quite significant. It makes an interesting point that the coal plants in the world release more uranium in their wastes than "...dozens of nuclear reactor fuel loadings...".

I respect the need for environmental controls, but I get annoyed by much of the 'sky is falling' 'the world is ending' mentality that seems to underlie much of popular news on this issue in general. Much of the science can be measured and thought about rationally. I appreciate the intention of this thread to actually put numbers to their discussion.

Comment: 2 cents from a PE in another state. (Score 2) 705

Personally, I am a PE in 2 states, but not in NC. General knowledge about how states run their rules is that a person has to make a claim that they are a PE before they can be found in violation. Most states take their cues from the NSPE/NCEES bodies. I believe that is probably the case here.

Reviewing North Carolina Law 89C23 which tells you that you aren't supposed to "practice" engineering without a license, along with 89C3 which gives the definitions of the terms used like "practice" you will find that a person has to make the claim to be a "professional engineer" {see section (6)a of 89C3} for their activities to be construed to be the "practice of engineering".

Laws are written this way to point out that while most anyone can technically fill a job title of "engineer" if they have the smarts at your local company making widgets, you are not allowed to provide "engineering services" to the public. What that usually means is that you are not allowed to design things that affect public safety. You are however fully within the law to work as an engineer for IBM, Caterpillar, Boeing, etc. Usually even if a company has engineering services, few engineers are actually licensed, they just work under the direct supervision of the license engineer who takes ultimate responsibility for the design.

With this in mind, unless David N. Cox made the claim that he was a licensed engineer or was providing engineering services, he and others like him are within the letter and spirit of the law. I read nowhere in the article that he made the claim he was an engineer, nor sealed/stamped the report/calculation/designs he provided as part of his petition. Unless he made the claims or sealed/stamped the articles associated with his petition and the article simply failed to state that, I believe Mr. Cox is probably innocent of the allegations made against him.

The chapter of the North Carolina Law relevant to this is found at this web location.

The NC engineering board will tell, but I am going to guess that they will rule in favor or Mr. Cox.

Comment: While there, if you do go Kayaking (Score 1) 278

by Grendol (#29140437) Attached to: First American Internet Addiction Treatment Center
Well, if you do spend time in Fall City, when kayaking or canoeing, go upstream and put in on the Snoqualmie river at the turbine house just past the base of the falls. It is a nice half day float, but don't bother going much downstream of Fall City as the river gets really slow to almost being stagnant and winds around forever before you get to Tolt River Park at Carnation.

Having been there, Fall City probably needs an AA program more than it needs a internet addiction program

Comment: Re:"for civilian use" (Score 1) 167

by Grendol (#28201147) Attached to: Secret US List of Civil Nuclear Sites Released
There are fundamental engineering differences in how the reaction is propagated in the RBMK Chernobyl rector vs the Three Mile Island(TMI) Pressurized Water Reactor (PWR) (

The US National Reactor Testing Station which is now the Idaho National Lab performed the Loss of Fluid Tests ( to better understand what a loss of coolant accident would mean ( Understanding that the loss of water which acts as both coolant and moderator for fast neutrons means the reaction cannot continue in a PWR reactor. The prevention of a Chernobyl like accident in the TMI reactor is far beyond 'Luck' as it was designed into the PWR from years of testing that occurred. The intent was to achieve what is known as 'Passive nuclear safety" ( which is a driving fundamental engineering for all modern reactors.

The Chernobyl reactor did not benefit from this fundamental engineering in the reactor design, and to top it off, it was revealed that they were performing a very risky and unwise test of testing an untested emergency core cooling system ( with many unconfirmed assumptions of turbine momentum and pump power being made used as excuses to perform the test on a full scale power reactor instead of in a lab reactor or modeling prior to accident with safety contingencies set up to prevent excursions. This combined with the low power level in the reactor and the impatience to approach such a condition properly, they added water and MANUALLY REMOVED THE CONTROL RODS to increase power in a xenon neutron poisoning situation, set them up for the catastrophe. The RBMK reactor was taken far from its normal mode of operation for this accident to occur, even with its less then modernly acceptable design and construction.

Such testing activities here in the US are probably criminal, someone from the NRC or with that knowledge would have to confirm that though.

Libel statements about shift workers at TMI DO NOT CONTRIBUTE to ANY good analysis and lessons learned for the Nuclear Industry.

As for the main topic's discussion of the accidental disclosure of various nuclear facility locations, most of them were probably unclassified anyway, and knowing where something might be (as stuff gets moved and the disclosed locations can change) is not even most of the battle. Physical security at these sights is probably set up on a military as opposed to a police scale, and organized with support from local military assets. The federal government may have the Department of Energy manage nuclear materials for the Department of Defense, but the Department of Defense still owns the materials. As for civilian locations, the guard forces are still fairly military like in nature, with well planned protocols for various events. This accidental disclosure probably does not increase risk in any significant way.

Comment: Some home (castle) defense options (Score 1) 828

by Grendol (#28033755) Attached to: I'll keep my castle secure primarily with ...
Well, a castle with a long straight entrance can use large rolling objects to crush the invaders with fairly good efficiency.The properly designed crusher will be roll-able back to a reloaded position for the next wave. If properly set up, a similar entrance could be turned into a water channel for temporarily diverted water sources to was the bad guys away.

Moats with pointy objects (spikes) concealed in them has had a fairly good deterrent. The moat must be at least 50% longer than two of the taller trees lashed together.

Moats with moat monster wildlife crocodiles, piranha, saltwater moats with sharks, jelly fish, etc have some effectiveness as long as the said monster(s) are in the mood to be pestilential.

Trap Door draw bridges may be effective traps.

Sharp Shooters with High powered crossbows have been good at sniping leaders of besieging forces, people manning siege engines, and Calvary charges to create a hole in their charge.

Mechanical power provided by waterwheels (~5hp) and windmills (~10 to 15hp) could be used to drive GNASHING SPIKED POWERED WHEELS OF DEATH HA HA HA HA, with reasonable effectiveness.

Anyway, it is not like I gave this any thought.

Comment: Re:Just Like When He Led Microsoft (Score 0, Troll) 841

by Grendol (#26742117) Attached to: Bill Gates Unleashes Swarm of Mosquitoes
What he did could very possibly be considered assault, or in today's climate of legalities a bio-terrorist attack. I believe the only reason nobody go up and kicked his ass is because of who he is, which is probably the only reason why he has not been arrested by DHS. They arrest other people for mailing unidentified powders as a joke now!

Making a point about how lame some parts of the world can be with diseases doesn't cut the mustard for this kind of stunt, anyone here at slashdot pulling this off would probably be arrested.

Nobody's gonna believe that computers are intelligent until they start coming in late and lying about it.