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Comment Re:Unintended Consequencies (Score 1) 347

You want professional landscapers to have repetitive stress injuries from sweeping 8 hours a day instead of leaf blowing? Manual labor isn't exercise. It's not about toughening up. It's about having energy policies that take reality into account. And honestly, that's more of a response that your lame comment deserves. Whoever gave your comment a mod 2 needs to have their /. account revoked.

Comment Unintended Consequencies (Score 1) 347

I'm totally onboard with transitioning to renewables and lesser-polluting technologies but I see several problems with this. First is, who's going to pay for all the additional battery disposal and where are the disposed batteries going? Oakland and Almeda County have long-term contracts with their hazardous waste disposal sites and this new ordinance will likely make their costs exceed their contract. Who's going to cover that? Also, those hazardous waste contractors are under no obligation to recycle the dead batteries. They could literally put the dead batteries in a 55 gallon drum in a hole in the ground, and they'd still get paid. Is that really better for the environment? Without making mandatory changes on the waste side, I don't see how requiring people to buy new technology is going to truly help the environment. For contractors and jobs too, how many professional landscapers can afford the switch to electric? A small 3 or 4 person landscaping crew could run a leaf blower for 8 hours a day. The best battery-operated blowers currently run for 30 minutes per charge and cost about $300 per battery. For an 8 hour day, you're going to need 16 batteries fully charged batteries, although you could potentially have as few as 6 batteries if you have a way to charge them during the work day. Either way, that's $1800 for 6 batteries or potentially as much as $4,800 for 16 batteries... which of course will all need to be properly recycled and replaced about every 2 years with high usage. Like I said, I like renewables where they make sense but IMO this policy doesn't make sense for the environment or for jobs.

Comment Re:And nothing of value is lost (Score 1) 135

I know it's trendy to hate on Google and they do deserve some criticism for hardline negotiating tactics, but let's not ignore that their search engine is very useful for searching academic and government websites in Australia and other countries. Yes, local search engines have their place but there is a lot of value in having a good search engine for global queries.

Comment it's got potential (Score 1) 79

As others have mentioned, the regulatory approval piece is big hurdle with something like this BUT there is still some good potential here... * Regulatory approval for 'me too' devices doesn't usually require clinical trials so the cost of regulatory approval would be less that some people have suggested. * The concept of 'open source' hardware is quite interesting. Rather than MobileECG design, build, and sell the devices all by themselves, perhaps they could focus on the design aspect so other companies can tweak the design, build and sell the devices. Essentially, MobileECG's open source hardware would be a reference architecture that other companies could use and provide feedback to. * Would be great to see a scientific study comparing the safety and efficacy of 'open source' vs 'closed source' medical devices. Since ECG devices are so common, this seems like a great opportunity with a relatively low-risk device.

Comment Re:Fixed-point arithmetic (Score 5, Informative) 226

Awesome link! I'm the OP and I really appreciate your response. The reason I'm looking into this is that I work with many scientists who use commercial software packages where they don't control the code or compiler and their results are archived and can be reanalyzed years later. I was recently helping someone revive an old server to perform just such a reanalysis and we had so much trouble getting the machine going again I started planning to clone/virtualize it. That got me thinking about where to put the virtual machine (dedicated hardware, cloud, etc) and it also got me curious about hypervisors. I found some papers indicating that commercial hypervisors can have variability in their floating point math performance and all of that culminated in my post. Thanks again.

Comment Re:You need to know some numerical analysis (Score 1) 226

I'm the OP and I really appreciate this comment. I did give some thought as to whether it was reproducibility or repeatability and I decided on reproducibility because the experimental equipment (underlying hardware and firmware) would be different, different analysts would be involved, and the replication of analysis would be occurring after a long period of time. I agree though that it's not clear cut in my post.

Comment Re:Fixed-point arithmetic (Score 1) 226

Nice, I'm the OP and I appreciate your comment and experimental design. I agree that in situations where you are coding the algorithm, it's easier to control/adjust for the variability with each hardware platform. The use cases I'm really wanting to learn more about are with commercial software packages that have traditionally been run on dedicated hardware and are now being virtualized and moved across multiple hardware types. I like your approach though and may do some testing along those lines.

Comment Re:Fixed-point arithmetic (Score 1) 226

Thanks for your comments, I really appreciate them. Your mention of experiments was spot on with the use cases I'm trying to learn about. I've worked with many scientists who use commercial software packages for biomedical research where their experimental results may be archived for 10+ years before being reanalyzed. I recently helped a colleague pull a Windows 2000 server out of storage to rerun an experiment. We got it going after some difficulty and that got me thinking about virtualizing the harddrive, which then lead me to wonder about the portability of virtualized machines between hardware hosts (including cloud providers) and the resulting reproducibility issues that could occur. I then read through several interesting papers showing variability of floating point math in commercial hypervisors, which lead to my posting on Slashdot. Thanks again. Some interesting links: http://faculty.cs.gwu.edu/~timwood/papers/im2013_tech.pdf http://www.vmware.com/pdf/hypervisor_performance.pdf http://www.cc.iitd.ernet.in/misc/cloud/XenExpress.pdf

Submission + - Ask Slashdot: How reproducible is arithmetic in the cloud? 1

goodminton writes: I'm research the long-term consistency and reproducibility of math results in the cloud and have questions about floating point calculations. For example, say I create a virtual OS instance on a cloud provider (doesn't matter which one) and install Mathematica to run a precise calculation. Mathematica generates the result based on the combination of software version, operating system, hypervisor, firmware and hardware that are running at that time. In the cloud, hardware, firmware and hypervisors are invisible to the users but could still impact the implementation/operation of floating point math. Say I archive the virutal instance and in 5 or 10 years I fire it up on another cloud provider and run the same calculation. What's the likelihood that the results would be the same? What can be done to adjust for this? Currently, I know people who "archive" hardware just for the purpose of ensuring reproducibility and I'm wondering how this tranlates to the world of cloud and virtualization across multiple hardware types.

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