Please create an account to participate in the Slashdot moderation system


Forgot your password?

Slashdot videos: Now with more Slashdot!

  • View

  • Discuss

  • Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

The Internet

Why the Journey To IPv6 Is Still the Road Less Traveled 157

Posted by samzenpus
from the that-has-made-all-the-difference dept.
alphadogg writes The writing's on the wall about the short supply of IPv4 addresses, and IPv6 has been around since 1999. Then why does the new protocol still make up just a fraction of the Internet? Though IPv6 is finished technology that works, rolling it out may be either a simple process or a complicated and risky one, depending on what role you play on the Internet. And the rewards for doing so aren't always obvious. For one thing, making your site or service available via IPv6 only helps the relatively small number of users who are already set up with the protocol, creating a nagging chicken-and-egg problem.

Comment: Re:Video from the barge (Score 2) 113

by catchblue22 (#49490813) Attached to: An Engineering Analysis of the Falcon 9 First Stage Landing Failure

Is there a reason the rocket has to land upright unassisted? What about some sort of bungee-mesh around the edges to catch it if it topples?

Parachutes are too heavy for a nine engine rocket, and would either land in corrosive seawater or on land with a hard damaging landing. To be truthful, they have already accomplished the most difficult part, namely bringing a rocket from 140km altitude to a tiny location in the middle of the ocean. They have also already demonstrated the landing part several times. If you notice, those landings come down at pretty much the exact location they began at.

Comment: False Dichotomy (Score 4, Insightful) 362

by catchblue22 (#49470147) Attached to: Can Civilization Reboot Without Fossil Fuels?

I believe global warming and ocean acidification is a serious threat. I also believe that solar energy has great potential as an energy source. However, I think the question being framed here creates a false dichotomy. Is it not possible that we might have a world where we have renewable, nuclear, and fossil fuels? Just because we reduce the use of something doesn't mean we have to eliminate it. The fact is that modern civilization needs plastics, mechanical lubrication, and other fossil fuel bi-products. Even if we reduce fossil fuel use by 80%, we can still have these things.

Comment: Re:"worst ever" (Score 1, Troll) 173

"worst ever drought"

It might be the worst drought since the area became a state (though there were others that were close if not worse) but it is far from the worst drought ever in the region. On at least 5 occasions over the past 1000 years there have been droughts that make this one seem mild in comparison.

Exhibit A: A freshly minted climate denier talking point. It was likely created by a "PR" company and focus group tested. It sounds like it comes from an expert...someone who has studied the climate history of California. However, no references are given. It merely relies on the confident tone to reach its target audience...the sector of society that has little scientific expertise and that doesn't want to believe that the truck in their garage is likely to make the lives of their grandchildren quite difficult.

Really, this all reminds me of Grima Wormtongue in Lord of the Rings. Seriously, watch Petropolis, and tell me you can't see Mordor in the Canadian tar sands.

Comment: Re:Missing the point. (Score 2) 330

by catchblue22 (#49407463) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

I really don't understand this hostility towards hydrogen.

It is hostility based on its physics, based on the simple fact that it will be a dead end. No technological breakthrough, no engineering project, no amount of effort or creative thought will change the fundamental lack of efficiency in this method of energy storage. It is wasteful of energy and will lengthen the time for our society to move to electric transportation. Governments will dump large amounts of money into it. Corporations will use it as their way of satisfying governmental requirements for green technology. But you will still in the end be left with a choice. If you want to move your electric car, do you want to lose 20% of input energy by using grid electricity to charge a battery or 70+% of your energy by using hydrogen. It is simple, unchangeable physics.

Comment: Re:Missing the point. (Score 4, Insightful) 330

by catchblue22 (#49406027) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

I think that Toyota hydrogen fuel cell is far more practical and cleaner (because electric batteries are charged with coal fire plant electricity made 500+ miles away from where it is used).

Really? Hydrogen? Ok. First off, hydrogen is an energy carrier, not a source. Most hydrogen for transportation these days comes as a bi-product of fossil fuels. So that's not really so clean.

So what if we make the hydrogen from H2O using electrolysis...that means we split 2 H2O molecules into 1 O2 and 2 H2 molecules. There is going always going to be some heat generated in this process, which is by definition waste.

The real and fundamental flaw in this process comes next. In order to transport and use the hydrogen, you have to compress it. This takes energy. Extra energy. And when you compress a gas, it gets warmer. This is a fundamental law of physics. So we have compressed hot gas. What happens to that heat energy? It will certainly not be used to power the car. It will likely be wasted.

Next, you have to transport the compressed hydrogen gas. This also takes energy. Energy that will be lost.

Another large problem with hydrogen gas is that the molecules are small. Why is that a problem? Because it will be difficult to contain the gas. It will tend to escape. The gas will be lost in compression, in transport, and in storage. It is likely that if you fuel your hydrogen car up and park it, you will lose most of your fuel to the air in several days.

Finally, we have to change the energy in the hydrogen back into electrical energy to power the electric motors. The efficiency of fuel cells is an engineering problem, but I suspect there is some intractable physics in there that will cap the efficiency. Let's assume a best case scenario of perhaps 50% efficiency for the cells. That is still a lot of waste. However if you factor in the losses from electrolysis, compression, storage as well, you will have an overall efficiency less than 50%. Probably quite a bit less. So let's say for the sake of argument that the entire process is 30% efficient, which I suspect is generous.

It is well known that the electricity transmission system is highly efficient. Some easy research should tell you that the transmission system is more than 90% efficient. When we charge a battery, there are come losses. But they aren't that high. Let's assume the charging system is 80% efficient. Overall then, that process would be 72% efficient (I think it is higher than that actually).

So, if you have 100J of energy that you wish to use to drive the electric motors in a car, you can use hydrogen, and get less than 30J to the motors, or you can use the electrical grid, and get 70J to the motors. Honestly, why would you use hydrogen? Especially since the fuel cells would be complicated, expensive, and of unknown reliability. Hydrogen as a fuel is flawed at the level of fundamental physics. These problems cannot be engineered away.

Comment: Re:Missing the point. (Score 1) 330

by catchblue22 (#49405783) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

range anxiety, ability to recharge cross-country, cold weather conditions

Here is a blog about someone's trip in a Tesla across the US in winter. I think that pretty much takes care of all of your points. But you might also be interested in the fact that Norway is one of Tesla's best customers. Here is a video of a Tesla P85D beating a snowmobile in a drag race on ice. And for your convenience, here is a google search with the query "Tesla cross country road trips".

I'm not sure why you have been marked "interesting" when your post is counter-factual or at least deceptive.

Comment: Re:other stuff matters also? I claim it does (Score 1) 330

by catchblue22 (#49405721) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

Electric cars (the ones you can get right now) are terrible when it is really cold or really hot.

Really? Were you aware that Norway is one of Tesla's best customers. I think Norway is a cold country? Here is blog about someone's trip across the US in winter. Here is a video of a Tesla P85D passing pulled over SUV's after a bad snowstorm. I don't see any blankets.

Oh, and Californians buy many Tesla cars. California is kind of hot, isn't it?

+ - Inexpensive Electric Cars May Arrive Sooner Than You Think

Submitted by catchblue22
catchblue22 (1004569) writes "According to an article in MIT Technology Review, a new peer reviewed study suggests that battery-powered vehicles are close to being cost-effective for most people:

Electric cars may seem like a niche product that only wealthy people can afford, but a new analysis suggests that they may be close to competing with or even beating gas cars on cost. The authors of the new study concluded that the battery packs used by market-leading EV manufacturers like Tesla and Nissan cost as little as $300 per kilowatt-hour of energy in 2014. That’s lower than the most optimistic published projections for 2015, and even below the average published projection for 2020. The authors found that batteries appear on track to reach $230 per kilowatt-hour by 2018. The authors found that batteries appear on track to reach $230 per kilowatt-hour by 2018. If that’s true, it would push EVs across a meaningful threshold."

Comment: Re:Don't worry actors (Score 1) 360

by catchblue22 (#49383125) Attached to: Why More 'Star Wars' Actors Don't Become Stars

To my mind, the difference is clear. It's Lucas.

I agree. I felt so sorry for Natalie Portman in Episode III. "Oh Ani! YOU'RE BREAKING MY HEART!" Seriously. I cringe. That is no one but the director.

Watch Natalie Portman in Black Swan. She is utterly brilliant.

Not that I hate Star Wars. Far from it. The broad story arcs echo many ancient myths and stories. George Lucas has said that he read Joseph Campbell's "Hero with a Thousand Faces" which surveys many ancient myths for commonality. The idea of a young boy escaping his mundane life to find his "hero's journey" is primal, as is the story of a son of facing the sins of his father. In my mind these things elevate Star Wars into the pantheon of cinema, in spite of the horrific dialog.

Comment: Re:WWJD? (Score 1) 1168

Couldn't that be said by BOTH sides of this issue? Wouldn't it be injustice to force a private citizen to enter a private business contract/engagement with another private citizen against their will and against their beliefs?

NO! In a democratic society, we should NEVER tolerate intolerance.

Comment: Re:Christian Theocracy (Score 3, Insightful) 1168

But you know what? Every article, every boycott and every protest is pushing them back. Similar bills are stalling or failing. The outrage at actions like these are causing more and more Americans to leave their religion in disgust. The more we drag this bullshit into the light, the more the theocrats feel the heat.

Fair enough, but what scares me is how many extremists are already in power, in Congress and in the Senate. And on the road to the White House. We as a society really do need to take a close look at what is known as the "christian dominionist movement". This movement seeks to establish an American theocracy with the rule of law given by the bible. We should think about what these people are actually proposing: the death penalty for abortion, both for doctor and mother. The death penalty for homosexuality. Here is an article to give you an idea of what I am talking about. A very good read on this subject is American Fascists.

It is easy to dismiss these people as being a crazy fringe. Indeed every society has its own lunatics. What is concerning is how this extreme form of christianity has infiltrated the main stream of christianity and what we commonly know as the christian right. What is extremely concerning is how many mainstream politicians share similar modes of thought to this movement. When I hear about laws such as what Tim Cook is writing about, I hear the clicking of a ratchet, bringing us a small step towards an American version of the taliban government.

Those of us with a sense of what is actually going on must work towards steering our society away from this cliff. Above all, we should promote the idea that although we live in a tolerant nation, we should never tolerate intolerance. The bastards who bring in laws like this should be run out of town.

Comment: Re:Now I understand her record at HP (Score 1, Interesting) 353

by catchblue22 (#49367087) Attached to: Former HP CEO Carly Fiorina Near Launching Presidential Bid

Chris Christy scares the bejesus out of me. His personality is scary. He is the kind of guy who in my opinion you don't want to give too much power. The way he shouts down people who are weaker than him particularly concerns me. This article is a good summary of him.

"Necessity is the mother of invention" is a silly proverb. "Necessity is the mother of futile dodges" is much nearer the truth. -- Alfred North Whitehead