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Comment: Re:Blaming the cables? (Score 1) 476

by ari_j (#46096527) Attached to: Tesla's Having Issues Charging In the Cold

My experience with solid-state batteries differs significantly from yours. Maybe it's just colder here in North Dakota. :)

Also, the Prius's heater uses engine coolant. It apparently has an auxiliary electric heat source and water pump to keep the cabin heated when the gasoline engine is shut off, but if they put the car together in a remotely sane manner that should result in redundancy rather than an additional point of failure. If the batteries or the gas engine fails you in the Prius, you still should not freeze to death.

In a Tesla, though, if the batteries fail you then you will freeze to death. While the same is true for the fuel line and pump on a gasoline car or, much greater risk because of fuel gelling, on a diesel car, I have not personally witnessed a properly maintained gasoline car that started and reached operating temperature fail because of fuel delivery issues, in a climate where -40C happens at least annually and for roughly three consecutive months each year the temperature does not exceed -10C on more than a small handful of days.

And that's what I mean about the Tesla being unproven. We have a century of gasoline and diesel engine experience so we know how to keep them working in extreme cold and the risk of problems is a known quantity. We also have a solid understanding of how to survive in the event of various problems that can arise. (As an example, if you are stuck in the snow but the engine is running, you ensure that the exhaust is clear so it can escape to atmosphere and then you stay in the car for warmth and safety.) For a hybrid like the Prius, the risks should be both similar to those in a gas car and also mitigated by intelligent engineering of redundant systems. They are still uncommon here, but that is likely more because they have low ground clearance than because they are hybrid. For a purely electric car, though, we have no experience keeping them running in extreme cold and the risk of problems is an unknown quantity. We also do not have a good understanding of how to survive if a problem arises. What do you do if you are stranded in cold weather by a dead battery and help will not arrive until morning?

Everything I have identified as a risk of electric cars can surely be quantified and likely be mitigated. But with gas cars we have a century of experience to draw on. It will be a long time before the same can be said for electric cars. And during that time, I will let people in populated areas where help or alternative transportation is within a 5-minute walk at all times learn and fix the problems before I incur the risk of a frozen battery leading to my own freezing to death.

Comment: Re:Blaming the cables? (Score 1) 476

by ari_j (#46094979) Attached to: Tesla's Having Issues Charging In the Cold
I have found that batteries fare very poorly in general in the cold. That includes the starting battery on my car, the battery in my phone, the battery in my camera, and every other battery of any chemistry that I have exposed to the cold. The difference is that an internal combustion engine warms up as you get farther down the road, reducing the risk of failure due to the cold. In other words, cold-related failure of a gasoline car is most likely to occur in your driveway where you can walk inside and survive. It seems that electric cars increase the risk of failure as you drive away in the cold. People who become stranded in a gasoline powered car with adequate fuel and do the right thing by staying with the car tend to survive. Electric cars that accomplish the same results are certainly possible, but not yet proven.

Comment: Re:Blaming the cables? (Score 1) 476

by ari_j (#46093335) Attached to: Tesla's Having Issues Charging In the Cold

This has always been my concern with electric cars. Batteries do not work well in the cold. I live in the part of the USA where Norwegians settled because it reminded them of home. Except we were having a heat wave at the time, and now it's colder. A warm gasoline or diesel engine will generally keep running no matter how cold it gets, so by the time you are any distance from the safety of your home, you have the safety of a running car with a working heater until you run out of fuel (assuming you have not filled with #2 diesel, which turns to gel in the cold). An electric car that relies entirely on batteries will get you just far enough from home to be in danger when the batteries have, due to temperature, become unable to move the car or to provide heat for the occupants.

I think an electric car would be great for the summer months. Maybe they should market electric motorcycles. But in the winter, living in a rural area where the ambient daytime temperatures are often -15C and occasionally -45C or worse, electric vehicles have a long battle to prove that they are as safe as their gasoline and diesel powered counterparts.

Comment: Re:Slashdot in Greek (Score 3, Insightful) 42

by ari_j (#45971889) Attached to: GNU Guile Scheme Gets a Register VM and CPS-Based IL

To those interested in the implementation of programming languages, it is immediately apparent that this is a fundamental change in the compiler behind the GNU Guile system which implements the Scheme programming language, inasmuch as it now has a virtual machine based on the register model instead of the implied stack model, along with an intermediate language in its compilation path that is based on continuation-passing style.

I think that the lesson here is for everyone: There are many segments of nerd culture, and it is very unlikely that any randomly-selected Slashdot reader understands and appreciates all of those segments. For example, the earlier headline today "Why Transivity Violations Can Be Rational" has no meaning to many readers, even after the title was corrected to spell transitivity correctly. After reading a little about that topic, I see that it is an area of of obvious interest to many nerds.

That being said, there are plenty of topics Slashdot poorly reports on which are not of interest to any segment of nerd culture, at least not beyond the overlap between nerd culture and the mainstream news where we already read the same information three days earlier except through the words of a literate, competent reporter with real editing before it hit the press.

Comment: Re:Belief in science? (Score 1) 434

by ari_j (#43941677) Attached to: Fear of Death Makes People Into Believers (of Science)
Maybe the underlying point is that people, on average, rush to believe in something that they don't understand when they are under stress. For people who have rejected religious belief but do not understand science, it is natural that they would rush to "believe" in science. This is a well-understood phenomenon.

Comment: Re:The farmer's recourse is to sue to sell (Score 1) 579

by ari_j (#43711945) Attached to: Supreme Court Rules For Monsanto In Patent Case

Assuming that there are negative effects of the current patent system in terms of seeds, there is still another side to the coin. Without patent protection, would Monsanto have developed Roundup Ready (TM) soybean seeds? Or, for that matter, Roundup (TM) herbicide? Without these complementary items, soybean production would be much lower. (Due to decreased production by using other means of weed control and/or increased cost of weed control.) Maybe both products would exist without the seeds being protected by patent law, but if, on average, the total production is increased by the availability of such protections, they give society a net gain.

Comment: Re:I wonder if New Zealand can do other tricks too (Score 2) 175

by ari_j (#43046143) Attached to: US Wins Appeal In Battle To Extradite Kim Dotcom

Keep in mind this is an extradition matter. At an extradition hearing, the issues are basically limited to (1) whether you are the person being sought by the other jurisdiction and (2) whether the charges in the other jurisdiction are the type of charges for which a person can be extradited. I am not as familiar with international extradition as I am interstate extradition within the United States, and certainly there will be specific rules spelled out in an extradition treaty between New Zealand and the United States (possibly by way of the UN, for all I know). But those are the real issues: are you the right guy and are the charges extraditable. The extradition hearing is held in and under the procedural law of the court in New Zealand.

Once arraigned in the court where the charges are pending (the United States federal court), the issue becomes whether you are guilty of the offense charged. And the evidence against you is relevant to that issue. The evidence is largely not relevant to whether you can be extradited. And that's essentially what it sounds like the New Zealand court concluded.


+ - Ask Slashdot: Language With Access-Controlled Sandboxes

Submitted by ari_j
ari_j (90255) writes "I often find myself in need of a programming or scripting language with good access control. For instance, a multi-user game where each user's code and data should have only the access to other users' code and data that is expressly granted. Basically, I want the kind of access control one would expect from a good database system except I want that access control to apply to objects and method calls rather than to tables, rows, and columns. I also tire of rolling my own language. What are my turnkey or near-turnkey options?"

Comment: Re:Why would that be the first step? (Score 4, Insightful) 206

by ari_j (#42136131) Attached to: Carl Sagan Was On US Team To Nuke the Moon
It's also proof of concept. If you can launch a nuclear missile from Earth and detonate it on or near the surface of the moon, particularly if you can get reasonably close to a specific position on the surface of the moon, then you can likely do the same in reverse. If you can't nuke the moon from Earth, then you can't nuke Earth from the moon.

FORTRAN is a good example of a language which is easier to parse using ad hoc techniques. -- D. Gries [What's good about it? Ed.]