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Comment Re:Sixty Years Ago... (Score 1) 38

It's great to see the myths of non-reusable first stage technology being dispelled.

Indeed, SpaceX has thoroughly demolished the claims of SSTO fans that reuse and low cost are somehow incompatible with staging.

We agree that this is a step forwards in getting to orbit.

We don't need wings.

They are useful though.

For what?

For operating a vehicle in atmosphere, which occurs at two critical stages of a spacecraft's mission.

Spaceplanes are dead.

Does a spaceplane have to include engines?

Take Skylon as a representative example:

No. That is specifically the design I am arguing against. Please check my post again and you will see I deliberately *exclude* the mass of the engines.

Perhaps it would make more sense if I introduced the term "Space Glider" to describe what I am talking about.

assuming it lived up to expectations, Skylon

I agree, I doubt this design would have lived up to expectations and what we have seen is failed designs for a sort of spaceplane with engines. What my OP was suggesting was that we have not seen the most optimized design for a space plane, or more specifically, a space glider.

Comment Re:Sixty Years Ago... (Score 1) 38

Well, it beats making them into the world's most complicated air planes as with the space shuttle. SpaceX has proven that they can do vertical landings of the first stage intact onto both land and a seagoing barge; after a trip out of the atmosphere and to about 1/5 of orbital velocity but not into orbit.

It's great to see the myths of non-reusable first stage technology being dispelled.

That turns out to be far less expensive and complicated than a space plane. It does turn out we need a lifting body for much larger vehicles. It still doesn't have to be a plane, though.

I think you have to separate the concept from the implementation of a space plane design. SpaceX's launcher effort is less expensive and complicated than the space planes implemented so far. However both Buran and the Space Shuttle had the orbiter on the side of the stack where their heat shield was exposed to debris from the launch vehicle. So much so it was considered to be 'In-Family' because it would occur every launch to some degree.

The Space Shuttle also had all of the complexity related to the main engines which had no business being in orbit. Having the mass of those engines also complicates the infrastructure of landing. Considering also many of the political issues that interfered with the implementation of the Shuttle it wasn't the best design for a space plane.

We don't need wings.

They are useful though. The contrast is having the space plane at the top of the launcher stack, which removes the 'in-family' debris, main engine mass and, complexity issues for operating a space plane, as the X-37 demonstrates. The X-37 is covered by a shroud, however having some control surfaces at the top of a launch stack for a larger vehicle could be useful considering launchers have control surfaces near the base to balance it. A less massive orbiter means more for vehicle and payload reaching orbit and returning.

Musk has taken the pork barrelling out of launcher design and shown that it is possible to recover launcher assets. That knowledge maybe the foundation of opening up commercial space ventures paving the way for more commercial launcher platforms to become available.

The good thing about commercialization could mean someone implementing a space plane with a better design or more specific role. With those things in mind maybe we haven't seen the most optimal design for a space plane yet.

Comment Re:Honest Question (Score 4, Insightful) 151

I think the most important usability features X11 has over Windows and mac is the suberbly powerful cut paste and remote display paradigm. If I can use those X features in Wayland I'll be happy, otherwise, I think you have a point Mr AC.

I switched from Windows to linux because I was sick of that shit, change for change sake. I want change for the sake of a usability improvment in a computing interface that I am compelled to use because it makes me more efficient at using a computer. I am an advanced user and I want an advanced interface. For me that is an ambidextrous mousing paradigm, remote windows, more advanced cut and paste, multiple desktops.

Frankly, UI configurability in linux has gone backwards since it got more popular, workspaces interfaces have *less* functionality than it did in 2008 when I could drag windows between workspaces and you could configure just about every aspect of gnome to customize your linux desktop experience. I didn't want a Mac or Windows UI and since their UI's adopted workspaces the functionality in linux seems to be dumbed down and advanced linux GUI features being domesticated.

Wayland looks like it is answering the need for backwards X11 compatibility with Weston so it remains to be seen if it will take the powerful features of X11 and leave some of the atropied aspects behind.

Comment Re:Wayland bashing (Score 1) 151

wayland initially was infested by the type of developers

Wayland was founded by the X developers who wanted to call it X12 but realized that people would freak the hell out if they fixed it the way that it needed fixing, based on their experience with X11.

Do you mean Kristian Høgsberg? I'm curious about how they needed to fix X11 and Wayland being the incremental successor X12, would you elaborate? Got a link?

Comment Re:What kind of pain will it work on? (Score 5, Interesting) 144

Does it only work for chronic pain or something in particular? I've tried to use it in place of aspirin to little or no effect.

I snapped an achilles tendon and to control pain after the surgery, I polished off over a litre of morphine and had been using codine for several months. I had reached a level of use where the doctor told me I was facing liver or kidney failure if he proscribed any more and he suggested THC as an alternative to the pain killers.

It worked while I healed, during rehabilitation and it took two years to be able to walk again. Six months to recover from the surgery and eighteen months learning to walk again all of which required some really painful physiotherapy. It took another four years before I could sit in a car longer than 20 minutes. I used and recognised signs of THC dependency as simply getting tired of consuming it. So it was a lot easier to overcome, reduce and tolerate the withdrawal symptoms of the THC compared to being on morphine or codine for that long which made me feel like a zombie unable to do much.

To compare physical amounts, 25 cigarettes of tobacco as weed would take me about a week to consume to deal with chronic pain. The same amount may take over a month to consume recreationally as I am physically unable to consume that much weed.

My experiences were that you won't get high or euphoric when you use THC as a painkiller, however the sensation of pain will reduce and that helps you to relax. It also helped maintain my appetite when I didn't feel like eating. I also suffered several spinal injuries and found pain controling that using THC left me more alert and functional compared to opiate based pain killers.

For me pain control with THC help me through significant physical trauma, several times.


The core of the argument is sound though. It costs ~$500k to put up a 100kW wind turbine. With energy at about 12c/kWh, each hour at full power would generate only $12 and would thus break even after 5 years of full-time, full-power wind

You are talking about the full site establishment costs there. Energetic costs to host subsequent generations of turbines at each site become the cost of replacing the wind turbine with a crane.

however the largest turbines catch wind only 20% of the time and are only 30-45% efficient, smaller ones even less. So you're looking at 50 years before they break even.

This is why "measures" like "Capacity Factor" are bogus measures, every power generation techniques has characteristic. For example, nuclear reactors only us 0.3% of the energy in the fuel so they are relatively inefficient too. Inavailability of a reactor to produce power due to maintenance or some other reason that keeps them offline. Once the reactor is available there is also the utilization of the power it produces, they may produce a good base of power, but that doesn't mean a nuclear reactor can follow demand that well.

That is off course if they never needed maintenance, these turbines are specced for 20-30years of service WITH maintenance but most of them last only half that long.

That is a good platform for the incremental advancement of wind turbine technology. You cannot do that sort of advancement with operational nuclear reactor technology until you build a new reactor.

Wind power is a loss at this point in time unless we jack the price of energy like Germany does, we need way lower costs and way higher efficiencies but for that we need rare earth magnets and the like.

Well it would be devestaing if wind power melted down and spread radionuclides into the environment however it would seem the worst they do is overspeed and catch fire. I see as more wind power installations are deployed the grid itself will change in the way it responds to availability, demand and utilization.

Solar is better (less maintenance) but it still doesn't compare to a well-maintained nuclear plant or other forms of clean energy.

It would be difficult to imagine a large scale solar plant having more maintenance issues that a nuclear power plant.

Comment Re:Marijuana prohibition is a farce (Score 3, Interesting) 95

Your "freedom" stops at others' freedom

Your freedom stops where someone else's begins. You have no right

from your potentially reckless and harmful behaviour under the influence.

You mean like drunk people? Here is the science what drugs cause what harm

Pot gets you high much more easily than alcohol gets you drunk

citation please

Comment Re:Marijuana prohibition is a farce (Score 5, Insightful) 95

Translation I want to smoke pot. Now let me rationalize it.

No need to rationalize it. People don't rationalize drinking beer, wine or spirits - they do it because they want to. Here is a rationalization for you, I like it, I laugh my ass off and I have a great time.

However as a painkiller that my doctor suggested for having a snapped achillies tendon it was a much better option than liver failure from the oral painkillers I was taking.

Legalize Pot and all other crimes will stop because Pot funds them.

Why are you or anyone else qualified to make value judgements about peoples choices that have no impact on you.

It makes so much money, they FUND other crime. That could all be tax money, deficit solved Thank you.

What it does is criminalizes a lot of people that should not be exposed to the prison system. If you can, for a moment step out of your prejudice and ask yourself if the pot someone is smoking will do them more harm in ten years than a two year prison term will do, six months into it?

Or how much policing for violent crimes a police officer can do if they are not writing up a pot arrest for 3 hours in the station? How much time is taken up in the court system dealing with cases, how many prison officers have to be hired to guard them?

What does it say about a society that has social controls for a plant that has been with humanity for so long that there are receptors in our brain for Cannabinoids?

Comment Marijuana prohibition is a farce (Score 5, Insightful) 95

It causes less deaths than tobacco and alcohol and prohibition of it is just another form of social control. The absurdity of the 'house of cards' that prohibits it has more negative effects on society than the plant has ever caused and that's before we start looking at the plethora of medical benefits it has.

Take marijuana off the black market and the funding for many other criminal operations will dry up.

Comment Re:How can you tell? (Score 1) 129

Nothing, aside for that it's a distributed attempt to get service, not denial attempt, so probably even more effective at clogging the system. They spent about AU$400,000 on load testing (Should've been more than enough).

Evidently they didn't do the load testing properly. If they can't get that right how can anybody expect them to secure personal data properly.

Yet they're forcing mandatory retention of personal data.

They don't want to admit this was wasted money, and their IT guy said "With this many people trying to fill it out at once it's just like a DDOS attack!" so they've just gone with it.

By claiming it's a DDOS it just proves even more that they can't secure anything. How can they be trusted to keep sensitive data if they can't get something so basic functioning properly?

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