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Ohio College Building Indoor Drone Pavilion

dj245 Re: PFAH! (42 comments)

It would be a lot easier to build, test, and debug a control system if you started with 0 wind and slowly increased to a steady wind and then later begin testing in gusts or random winds, wouldn't it? PID control fine tuning goes a lot faster when you have full control over the inputs.


Coal Plants Get New Lease On Life With Natural Gas

dj245 Re:Gas not less CO2 on refiring coal plants (142 comments)

If you just replace coal with natural gas in the same plant to heat the water it is not significantly less CO2

Burning coal is pretty much just turning bulk carbon into carbon dioxide. Burning natural gas (methane, CH4) creates carbon dioxide, too, of course, but also releases energy from burning the hydrogen to make water. As a result, the combustion of natural gas produces less CO2 for the same energy output. From the Energy Information Agency - Pounds of CO2 emitted per million BTU of energy: Coal (anthracite): 228.6 Gasoline: 157.2 Natural Gas: 117.0 [I'll apologize for the units - I'm just quoting the result. If you must know, 1 lb / 1e6 BTU is equivalent to 0.43e-3 kg/MJ. Or, just look at the number as a figure of merit: lower is better.] more data here

It is even more effective than that- these numbers don't take plant efficiency into consideration. The "per million BTU of energy" is just the amount of heat produced, not the amount of electricity. A very efficient traditional coal plant is about 35-40% efficient in turning the heat into electrical power. A typical combined cycle gas power plant is about 57-60% efficient due to the nature of the different cycle. So, on a per-MW produced basis, Natural gas looks a lot better.

It also doesn't hurt that natural gas is at all-time low prices in the US thanks to our gas boom and the high cost of transporting natural gas across oceans. Gas is cheaper than coal now in many places. The only coal plants which are going to survive are the more efficient plants with short coal supply lines. It has little to do with environmental concerns, it is strictly an economic calculation in many cases. The environmentalists didn't defeat coal, the accountants did.

4 days ago

Coal Plants Get New Lease On Life With Natural Gas

dj245 Re: It's still reacting carbon and oxygen... (142 comments)

That was then. Today we have settled on standardized new-generation plant designs that avoid this problem.

What's really needed is a change in our legal system to eliminate the disproportionate power that small groups of activists have to disrupt construction. Their strategy is to raise costs by imposing phony legal delays on construction after the initial approval.

As a guy who very recently was involved in selling new power station equipment, I can say with 100% confidence that there is no such thing as a standardized power plant design in the USA. I was selling turbines to Duke, Southern Company, Exelon, Luminant, and many others. Every customer wanted something different. Some of them wanted triple redundant instruments on valves, and some were happy with dual redundancy. Some of them wanted the generator protection system to be redundant on 2 different vendor's kit, and some wanted redundancy with identical cabinets from the same vendor. Some wanted a stainless steel oil tank, and some were fine with the carbon steel + epoxy coating tank. Some of them wanted to have a large turbine deck to make maintenance easier, and some were cutting that cost since they were going to flip the plant anyway. We went into great detail about even the most mundane of things. Some of the customers wanted to have all our equipment numbering changed to their (internal and proprietary) numbering standard so that all the plants they owned had the same numbering scheme. No matter what our "standard" design was, someone had a problem with it. These guys know what they want and if it isn't included in your "standard" design, they want a price to make it happen.

This is a different philosophy from Europe and Asia, where standard designs are common and even preferred. But that's the US power market. Toshiba/Westinghouses' standard AP1000 plant isn't good enough for any of the US utilities who can afford to build such a thing. All the customers have their little quirks of wanting to be a little more safe in one area, or a little more convenient to operate, or a little cheaper to build. None of those changes affect the core safety principles of the design, they are just different. They do, however, drive up the build cost. Additionally, these plants don't get build often enough to keep the same crew on each job. By the time you build Unit #2, 10 years has gone by and a lot of the people who built Unit #1 have changed jobs or retired. It is difficult to keep such specialized experience in the economy if it is needed so rarely.

4 days ago

US Intelligence Unit Launches $50k Speech Recognition Competition

dj245 Re:Out of touch with reality (62 comments)

I am sick of these "challenges" that effectively try get programmers to work for effectively well below market rates. As if we're like children, a "challenge" is supposed to make us set aside months or years of income to work on a really difficult problem that if we had to actually go out and do for a company in the job market, we'd be paid $100K/year or more..

You're completely missing the point. They've found the Stargate and egyptologists are a dime a dozen. They need to form an elite team of programming and AI experts who will decode the symbols on the Stargate and defeat Apophis. This is just a fancy recruitment test.

5 days ago

Military Laser/Radio Tech Proposed As Alternative To Laying Costly Fiber Cable

dj245 Re:cheaper perhaps (150 comments)

But it sounds inferior in many respects. Lasers require line of sight, which is obviously a problem. We really ought to be investing in quality infrastructure.

Are you going to pay for it? Laying fiber is insanely expensive. Not because of the trench or even the fiber... it's the home owners that are the problem.

Imagine I show up at your house and tell you I'm going to dig an 8' deep trench across your yard for Fiber. What are you going to do? And your neighbor? And his neighbor? ... and the other thousand people whos yards get trenched? Lawsuits... and that doesn't even cover all the roads, driveways and sidewalks you have to dig up.

Why are you digging a 8 feet deep trench for fiber?!? Laws in different states seem to vary, but between 2-4 feet is plenty. If you use a ditch witch style machine, the trench is only a couple of inches across on the surface. If you wanted to do it really well, you could cut a strip of sod out, but it to the side, and put it back when you were done.

about a week ago

Assassin's Creed: Unity Launch Debacle Pulls Spotlight Onto Game Review Embargos

dj245 Re:Depends on Embargo Lift (473 comments)

It's one thing to prevent game review sites from playing one-upsmanship over each other by "leaking" early reviews (that are often incomplete and based on beta versions of the game). However, once you can buy the "finished" product, the only reason to have a continuing embargo is that you know the product sucks but you don't want to share that information.

Another strategy: Have game review sites flat out say that an embargo for a certain game is NOT lifting prior to the game going on sale. I know lots of NDAs have Fight Club clauses (you do NOT talk about the NDA).. but a clever game review site could probably get around that without actually saying "The Assassin's Creed Embargo Does Not Lift Until 11PM" or something similar.

Its astonishing to me that anyone agreed to operate under such an NDA anyway. 17 hours is sufficiently long that you could aquire the game, play it for 2 hours to get a feel for it, 1 hour to record a video, edit for another 2 hours, and then post it with 10 hours left on the embargo.

Any game company having their embargo end long after the game is available is just begging for trouble. Or they know there is a very serious problem and they can't or won't delay the release.

about two weeks ago

U.S. and China Make Landmark Climate Deal

dj245 Re:Ya...Right (285 comments)

The same could be argued of the US. It just ignores agreements and treaties when it suits itself. Pretending that China is any worse is just borderline racism.

No, it isn't racist. It is hypocritical, but race has nothing to do with it.

Additionally, China has a documented and lengthy history of completely ignoring the environment, so expecting them to continue to do so is a reasonable reaction.

about two weeks ago

President Obama Backs Regulation of Broadband As a Utility

dj245 Re:ISPs don't want to take Cogent's money (706 comments)

Thank you for giving us the Netflix perspective. Counter arguments:

1) Residential broadband networks were never engineered as video delivery systems. The advent of mainstream streaming video completely changed the engineering calculus for last mile networks. Over subscription ratios need to change to accommodate the higher peak hour bitrates; this takes time and costs money. Where should this money come from? Why should I pay the same for my connection as the household that's running three or four simultaneous HD streams during peak hours? My 95th percentile is less than 0.5mbit/s, yet I pay the same as my neighbor who regularly runs three HD streams at the same time. Hardly seems fair, does it?

Internet is a utility in developed nations. Regardless of its legal status, people in developed nations can't function without it. The cost to build it out gets spread among everyone, because that's the only fair way. I don't get to complain when the city raises rates to upgrade a water main or drill a huge tunnel for sewage storage, even though I use 1/100th the amount of water of a nearby business. The cost to run the infrastructure to the endpoint, but the backbone is shared by all and the cost must be split by all.

about two weeks ago

We Are Running Out of Sand

dj245 Re:This is rich! (264 comments)

Well, you joke, but fine sand is no fun at a beach. On Galveston's East Beach, for example, the sand is very fine. Up on the beach it is not bad, and the dry sand feels pretty good on the feet. If that same sand is wet though, it is no fun at all. It feels like ocean bottom ooze or muck. Fill up a bucket with this wet sand, and you can't pour it out no matter how hard you try. It has to be washed out of the bucket with large amounts of water, and even that isn't easy. It becomes almost like wet concrete in the bucket, but if you DO manage to get it out, it won't build a very good sandcastle, at least with my amateur sand-castling skills. It's no fun to play in if you are a child. My son got very frustrated with it.

A quality beach needs good sand and it seems like they like a quality beach in the middle east.

about three weeks ago

Silk Road 2.0 Seized By FBI, Alleged Founder Arrested In San Francisco

dj245 Re:I have said it before... (219 comments)

... And I will say it again: if the FBI can arrest these people and bring down these ''black'' markets, who are supposed to be on Tor and protected by iron-clad crypto, it means only two things:

1. Tor is not as secure as everybody says it is (because _____ insert your favourite conspiracy theory/security failure here).

2. NSA/GCHQ, etc... justification for snooping on everyone (terrorists! drugs! guns!) is just complete and utter bull****. Hard detective work pays every time, and is probably more cost-effective than the massive surveillance and privacy violations we have right now.

Please note that 1 and 2 are not necessarily opposed to each other. We may well have 1 AND 2 at the same time..

Or 3- that the steps required to be completely anonymous on the internet are so demanding, and must be done without a single mistakes at any time ever, that no real human can obtain complete anonymity.

This guy made some pretty serious mistakes. We can all get our heads together and develop a plan on what he should have been doing instead. But actually following such a plan, to the letter, without ever making a mistake, seems nearly impossible.

about three weeks ago

The Plane Crash That Gave Us GPS

dj245 Re:timeline (236 comments)

But in 1995, as promised, it was available to private companies for consumer applications

Say what? There were consumer GPS receivers in the late 1980's, in fact in the first Gulf War (2 August 1990 – 28 February 1991) many soldiers used commercial units purchased from US retailers because the crypto hardened milspec units were in such short supply. In fact I'm not sure what they're referring to with the 1995 date, since the biggest change wrt consumer use was Clinton's order to permanently disable selective availability, but that wasn't until 2000.

I believe the 1995 date refers to the date at which the GPS satellite constellation was completed, in other words when the full set of 24 satellites was operational. You need just 4 signals to get a cold location fix without making assumptions, but prior to 1995 it is probable that in some parts of the world, 4 satellites were not visible at certain times. Prior to 1995 the system wasn't complete.

I can't find any information in 1980s GPS units, but given the nature of the calculations required to obtain a locational fix, and the processing power available in that era, they must have been excitingly expensive.

about three weeks ago

Scotland Builds Power Farms of the Future Under the Sea

dj245 Re:at least try to be accurate? nah, this is /. (216 comments)

If each Hammerfest machine delivers its advertised 1MW of power, then you need 1,000 of them to hope to match the output of a typical gas or coal-fired power station.

No, that's not "typical" at all. The largest coal-fired plants are 1-2GW; currently I believe there is no gas-fired plant anywhere in the world that is 1GW. So it would be more accurate to claim 200-500, while 1,000 is pure exaggeration.

Well, that depends on how you count. A single coal unit really maxes out at about 1200-1300MW, although these are pretty rare. More typical is a unit in the size range of 400-900MW. Note that the viability point is somewhere 150-300MW right now in the US for a coal plant. Anything smaller will have a hard time making money right now given economies of scale and the low low price of natural gas. Multiple small units still aren't cost-effective. You need the big machine to make money nowadays in the US. Many coal plants have multiple units on site.

As for gas power plants, they are at 1000MW now, and have been. Turkey Point uses 3 gas turbines and 1 steam turbine in one "block" to produce around 1150MW, and was completed in 2007. 2 on 1 (2 gas turbines, 1 steam turbine) blocks are more common in the industry. Recently gas turbines have increased in size to the point where this can also break 1000MW. The Mitsubishi G and J class turbines, Siemens H class turbine, and GE's 7HA.02, are all of the size to build 1000MW+ natural gas power blocks. Keep in mind that for a typical unit of this size, each gas turbine will put out around 300-350MW, and as a rule of thumb, the steam cycle can utilize the waste heat to recover about 50% of the MW of the gas turbines. So for a typical large gas turbine plant in the most-common 2 on 1 configuration, there are 330MW from each of the 2 gas turbines, plus another ~330MW from the steam turbine, for a total of around 1000MW. That's without additional duct firing (burning additional fuel in the waste heat recovery boiler), which most US gas plants utilize since gas is so cheap here.

about three weeks ago

Chinese Hackers Mess With Texas By Attacking Fracking Firms

dj245 Re:Good (104 comments)

Nothing wrong in the eyes of the Chinese or Russians to cause a nat gas plant to go up. I'm sure they want payback for when the CIA did it to them in the Cold War.

Problem is that a lot of companies pay at best lip service to security. "Security has no ROI" has been a mantra I have heard quite often.

Of course, little to nothing will be done about it. I remember solar companies getting hacked a few years ago, then China making solar panels of their exact same designs, then dumping them onto world markets for cheaper than the rare earths. It killed the US solar industry. I couldn't be surprised if this is the same with the natgas industry since there are a lot of reserves China has access to.

I strongly doubt that. Even a little familiarity with the industry would cause you to conclude the exact opposite. Natural gas in the USA is CHEAP. Natural gas in Europe and Asia is roughly 4x more expensive. Even Russian natural gas, in Russia, costs about 3x more than US natural gas. The problem is that shipping natural gas long distances is expensive if no pipeline exists. Ocean shipping of natural gas relies on cryogenically cooling the gas into a liquid, which is energy-intensive (expensive). Then, on the ocean journey, the ship either must burn or discard all of the evaporating gas, or expend even more energy with an on-board liquification plant.

Natural gas in the USA will continue to be produced in North America and consumed in North America. Even if the Chinese can solve the transportation problem, they will sell to their domestic market first, Japan/Korea second, Europe third, South America and Africa fourth, and only then would it make any sense to try to undercut the staggeringly cheap USA natural gas. The only loser with China getting strong into fracking would be Russia, and the environment.

about three weeks ago

YouTube Opens Up 60fps To Everyone

dj245 Re:interesting material? (152 comments)

Could you give some links to interesting material in 60FPS? I found just games.

I had a couple time-lapse videos which I made from an in-car video camera. Obviously they were sped up from the source speed, because watching a 6 hour car ride in 3 minutes is a lot more entertaining than watching in real-time. They looked great at 60fps but were dreadful at 30 fps. So dreadful, in fact, that I removed them from Youtube long ago.

about three weeks ago

In this year's US mid-term elections ...

dj245 Re:mailed my ballot a week ago (551 comments)

I live in Oregon where everybody votes because it is painless, since we vote by mail. So, I will not vote for any of the parties, because I already voted. All we have to do now is count the votes.

Must be nice. The fall and the spring are my busy seasons, and I do a lot of traveling in both. I have traveled the past 6 or so election days. I tried to get a Texas absentee/vote by mail ballot and it is incredibly difficult. Unless you are in the military or can prove that you're handicapped, you can't have one. A suspicion that "I won't be in town" isn't good enough.

Sure enough, my boss called me an hour ago and I am on flying tomorrow and won't be in town to vote. Maybe I can get lucky and find an early voting station but my schedule probably won't allow for that.

about three weeks ago

Ask Slashdot: Where Do You Stand on Daylight Saving Time?

dj245 Re:I live in Arizona, and it's a pain (613 comments)

TV schedules? Like, from the 20th century? My grandfather read about those in a history book once! People use to schedule their lives around entertainment which was, get this, broadcast to everyone at the same time. Weird, right? It's true, the past is a foreign country.

Broadcast to everyone at the same time? You mean like Multicast? How did they ever get that working right on all the myriad of different router models?

about three weeks ago

Skilled Foreign Workers Treated as Indentured Servants

dj245 Re:the bottom dregs for the cloistered elite. (284 comments)

Slightly offtopic...

These companies insist you work in armpits like Bentonville Arkansas or Decalb Georgia so your salary can be shuffled down the chain to 40 grand a year not under the implication that your services are worthless, but under the assertion that the "cost of living" is so inexpensive you shouldnt need a respectable wage.

As a midwesterner, I'd like to tell you firmly to go fuck yourself ... but also I'm far too polite to do that.

Instead maybe realize that wage costs are only part of having your business in the "armpits" -- and a pretty small one at that. Real estate, utilities, shipping, taxes, buildout costs, and a lot of other factors make flyover states a financially beneficial place to locate a business. With tech jobs there's no geographical need to pick a particular location other than space, power and bandwidth -- and those can be bought. Why not go cheap?

There are people who would want to live in such places, and there are people who would rather not. My company has 3 offices, head office/repair facility in rural Missouri, manufacturing facility in Houston, and a sattelite office in the country of Colombia. There was no way they could entice me to live in rural Missouri, but they were flexible enough to allow me to work in Houston. They got the person they wanted for the job, and I got a job.

There are lots of companies, though, who are not flexible. Stipulating that employees must live in a place they don't want to artificially limits their pool of potential labor. It also fosters resentment among employees who don't want to live there but really need a job. Companies are shooting themselves in the foot in the name of saving a few bucks. My company has millions of dollars of equipment including welding, machining, rigging, tooling, trucks to move the equipment around, etc. Yet most of the value of the company walks out the door every night. Our differentiator is in the quality of our people, and we attract quality people because we give them a lot of rope and look out for their needs.

With tech jobs there's no geographical need to pick a particular location other than space, power, bandwidth, and the happiness and loyalty of your workforce.

about a month ago

The Largest Ship In the World Is Being Built In Korea

dj245 Re:Ho-lee-crap (275 comments)

I suspect it is a space limittion more than anything that prevents most western shipyards from building multiple ships that size. ...... Cheap labor long ago reduced shipyards in most western countries to building military ships and some extremely spicalised or luxury ships.

You just contradicted yourself. Western shipyards aren't limited on space. If you have the demand, you can always get more space / capabilities / labor / raw materials. They are limited by demand.

about a month ago

The Largest Ship In the World Is Being Built In Korea

dj245 Re:Ho-lee-crap (275 comments)

No, when you are working on such a massive scale they really aren't simpler, the engineering and sheer weights alone are astronomical.

Not really, the numbers are larger but the math is very well understood. This is a very mature industry, perhaps the oldest manufacturing industry in the world. People have been building boats for thousands of years. Ship's aren't redesigned every time one is built either. The bulk of a ship is the exact same "U" profile. Design it once, copy it all down the length of the ship. The bow and the stern are the only complex parts, but contribute little to strength. The bow and stern are generally proven designs which are taken "off the shelf" and adapted to the application with only slight changes. Chopping off the back end of a ship (accommodation, engineering, and propulsion area), refurbishing it, and welding it to a brand new ship hull is not uncommon. Unlike with pleasure craft and cars, "style" has approximately 0 design influence in large ships. Everyone is honing in on the most hydrodynamic designs and you can't copyright the math which describes the curves on a ship.

I'm onboard the Tolteca right now, built in 1954/1955. When we were in drydock, the only difference between this ship and ships built much more recently is the distinct lack of a bulbous bow, and the use of diesel propulsion engines instead of a steam turbine.

about a month ago


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