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Comment Re:Saltwater and MTBF (Score 1) 90

Even though it is a tough engineering problem, i'm sure that there are solutions out there.

For instance I have heard many times the nuclear industry to claim that they have solved harder problems with their molten-salt breeder designs.
So if they have found a way to handle super-heated, radioactively saturated, oxidizing salts, how much difficult would be to handle sea-salts at standard temperatures?

Comment Re:Correct (Score 3, Informative) 328

They US authorities on '60s started trying gravity on various types of reactors for many years (passive cooling) and it failed miserably all times. Download the excellent BBC's 1992 documentary on the subject A is for Atom, or watch it on YouTube.

It was after they had confirmed the problem that they started installing diesel generators to operate the cooling pumps. The problem was discovered also in USSR. Chernobyl erupted during an experiment to test the cooling apparatus while disconnecting the plant from grid.

The root cause of all this was that they designed the commercial Nuclear Plants by scaling the 60cm diameter Submarine Reactors into 3 meter or even more. That way, the multiplied the fuel mass x1000, and disregarded that fact they were no longer 100 meters deep below the ocean surface, something that would guarantee passive cooling simply by hydrostatic pressure.

Comment Re:CMDB: GLPI, I-doit etc (Score 2) 114

SemanticMediaWiki(SMW) can utilize triple-stores (proper RDF databases). But even without using one you can make still run queries from within wiki. You create the new query by using a special query-page and after you are satisfied with it, you embed it in any wiki-page. Next, whenever you view this page, the semantic-results come always fresh on that page. Compared to a RelationDB, SMW comes bundled with UI. You just have to learn a new syntax for running the queries.

Now to get the results in different formats you have multiple choices. I remind you that each wiki-page is at the same time a REST API. And SMW follows this path, providing specific query-parameters for getting query-results as CSV, as XML, as text, as html-tables, or any html-structure. And there are numerous extensions for embeding the results into google-maps(assuming they are geo-coords), event-calendars (assuming dates), graphs, trees, and many more.

Comment Re:Semantic Wiki (Score 2) 114

Actually nobody likes to be reminded of the hierarchy above him or her. And most of the times the official hierarchy-diagram does not denote the complete command-and-control relations. Therefore, i skipped the political part of the "fairly accurate reflection of the way the business itself is organized" and concentrated on the technical aspects of the business, some of which i described above. Assuming that all technical data were complete, you could grasp the way the busines is organised by running queries resulting in cluster of related entities (hosts, subroutines, data-flows, developers and their capabilities, projects, etc). That way you get the *actual* picture, but only indirectly. But that assumption does not alwayd stand...

Regarding the "gaps", you are quite right. Those departments that lack proper documentation, usually avoid the semantic-wiki altogether. And those that participate in the wikie, spot and fill-in the gaps. I expect that these attitudes come with the territory of beaurocratic companies.

Another interesting observation is the quality of content that each department genarates. Those involved in the marketing produce the most vague page-entities with less interconnections, quite the opposite from the technical stuff that makes a good and innovative use of the wiki. Whenever an administrational person participates, good(tm) things happen, such as resolving HR problems, deciding on postponed decisions, and so on. But those people have hardly the time required to participate.

Comment Semantic Wiki (Score 5, Interesting) 114

Last year i used MediaWiki's SemanticWiki to describe the systems, projects, human-resources, external-urls and their dependencies of a telecom.

Besides trivial parent-child relations among developers/employees, departments, etc,
i described system dependencies as semantic-relationsships with names like this: part of, invokes, build by, implements, deployed on, etc.

I described developer responsibilities with names like this: maintained by, coded by, external contact, etc.

Finally, the documentation pages and the refs to external-URLs of projects were reorganized by semantic-relations, like this: javadoc, docUrl, webApp, section of, help page, etc.

Comment Re:Sounds like (Score 4, Informative) 1229

I'd also like to point out that you have been eating GM plants your entire life. Wheat? Hundreds of years of selective growing of only the best stock. Its the same thing it's just been done on a farm instead of in a lab.

Do not spread diss-information.
These are not genetically modified, crops, they are artificially-sellected crops.

Comment Re:Nothing to worry about (Score 1) 580

Had they been in the middle of decommissioning when the quake/tsunami hit there could have been 6 reactor's worth of screaming hot rods in the upper containment pools.

But then they wouldn't need electricity to operate those high-pressure pumps,
a simple hose on each one of the 6 reactors would do the job, or even simpler, they could have done it with buckets of sea-water!

OTOH, a Nuclear Core tightly sealed inside a Containenment Vessel is different beast to cool.


Submission + - A Giant Cargo Ship's Pollution = 50 MILLION Cars (

thecarchik writes: One giant container ship pollutes the air as much as 50 million cars. Yes, that's 50 million. Which means that just 15 ships that size emit as much as today's entire global "car park" of roughly 750 million vehicles. Among the bad stuff: Sulfur, soot, and other particulate matter that embeds itself in human lungs to cause a variety of cardiopulmonary illnesses. Since the mid-1970s, developed countries have imposed increasingly strict regulations on auto emissions. In three decades, precise electronic engine controls, new high-pressure injectors, and sophisticated catalytic converters have cut emissions of nitrous oxides, carbon dioxides, and hydrocarbons by more than 98 percent. New regulations will further reduce these already minute limits.
But ships today are where cars were in 1965: utterly uncontrolled, free to emit whatever they like. Just one of many statistics: A car driven 9,000 miles a year emits 3.5 ounces of sulfur oxides--while the engine in a large cargo ship produces 5,500 tons.

Comment Re:KDE needs some competition. (Score 2, Informative) 196

Why do so many programmers are still unaware of Bash's string-parsing built-in capabilities,
and prefer to use the 'basename' command instead?

For the above renaming one would suffice to type:

mv $f ${f%.*}.jpg


Comment Re:Motion blur and bloom effects (Score 2, Informative) 521

Speaking of Physics - the properties of a game's physics engine have the properties of a Riemann sum where n=fps. so the higher your FPS the more accurate your physics simulation, even if your monitor cannot discretely display all those frames.

[note: only applies in games where physics ticks/sec are tied to framerate... which is almost all games]

Actually all decent FPS engines have geometry/physics engines quite distinct from the graphics-pipeline!

The geometry/physics engines work on body bounding-boxes and their respective velocity-vectors describing their trajectories, and they try to solve the intersection-problem among all bodies with regard to time, by responding with a timestamp - the collision-timestamp - to questions like this:

"When is body A going to hit body B?"

And on that collision-timestamp an event is scheduled, for the game-logic to kick-in, to calculate the new body-trajectories, or deaths, new body births, sarpnels, whatever.

The physics/geometry usually runs on the game-server *simultanesous* with the clients to avoid sending back-and-forth excessive info into the network. The server is only authoritative for the game-logic decisions. Yet the client runs additionally the graphics-pipeline which uses the next-frame's timestamp to calculate the body-positions on the 3D space.

But sometimes there is a slight delay between the collision-timestamp and the response from the server about what to do next (the game-logic's decision), that may allow a body to be drawn past its collisions point, and this is what make us think that FPS affects physics.

To sum it up, fps has nothing to do with physics, even if some times it seems that way.

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