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jroll

254 karma · joined April 22, 2011

email: jim at jimrollenhagen dot com

Software Engineer at Rackspace. My posts are my own.

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jroll··on Ubuntu's Plans To Implement UEFI SecureBoot: No GRUB2
Does this mean it might be possible to install Ubuntu on ARM devices preloaded with Windows 8?
jroll··on Exploiting Silicon Valley For Profit (and Maybe Fun)
A modest house in the valley costs something like $500k. With a typical mortgage you can expect to pay about 1% of the total price ($5k). That's more than triple your total expenditures, let alone housing costs.
jroll··on Teardown reveals Chevy Volt's electronic secrets
That's a good question. Everything eventually connects in to the ECU, so there's no reason the customer shouldn't be able to read this data. As for writing data, I'm not sure how difficult it would be, but it can probably be done.

Personally, I'd leave battery controls to people smarter than me. Consider that the battery costs around $8,000, and that severe over- or under-charging is a massive hazard to both the battery's lifespan and the driver's life.

jroll··on Teardown reveals Chevy Volt's electronic secrets
They definitely contribute to range and torque, but the most important contribution is to the overall lifetime of the battery. Batteries treated nicely are apt to last much longer. Thermal management is probably THE most important factor in a battery's lifetime.
jroll··on Teardown reveals Chevy Volt's electronic secrets
I don't know anything about the Mitsubishi. The Leaf definitely has a capacity advantage (at the cost of weight), and is approximately the same chemistry. The Volt's thermal and electrical controls are vastly superior to the Leaf.
jroll··on Teardown reveals Chevy Volt's electronic secrets
I do not; that was after I left. I can tell you that they do extensive abuse testing at that facility.

I tried my damnedest to find out, but nobody would talk. :(

jroll··on Teardown reveals Chevy Volt's electronic secrets
I used to work at the hybrid battery lab at GM, and for a while on the Volt battery itself. I'm happy to try to answer any questions (without breaking confidentiality, of course).
jroll··on Teardown reveals Chevy Volt's electronic secrets
They are indeed for modularity. One benefit here is that dealerships can quickly swap part of a battery (cells and controller) to make repairs quicker. The other benefit is that smaller batteries can be made by using the same components and code.
jroll··on Introducing The New IFTTT
Lockitron also offers locks with a keypad, and every lock comes with a Bluetooth keyfob for emergencies like this. <3 lockitron.
jroll··on Linode Birthday Giveaway
They actually recently released information about this - there were multiple vulnerabilities in xen.civwould assume they were trying to keep the information quiet until the issue was fully resolved.

http://blog.linode.com/2012/06/13/xen-security-advisories-an...

jroll··on MacBook Pro gets Retina Display; MacBook Air updated with Ivy Bridge
Try Lock Me Now [1], which lets you lock your screen from the menu bar or configure a keyboard shortcut.

[1] http://itunes.apple.com/us/app/lock-me-now/id464265594?mt=12

jroll··on DrChrono Lets Doctors Accept Payments Via Square, View Real-Time Insurance Info
> As a doc you can already use Square to process payments

Yes, but the application is integrated with the Square app to make it more efficient. Payments made via square also automatically sync with our billing/accounting section of our application, which saves the doctor/biller a lot of time. If the doctor is solely using square to take patient payments, then the accounting is basically automated through our system.

> you can look up "real time insurance information" easily already via the web.

Most doctors call the insurance company directly to verify eligibility. Checking via the iPad (which is already used to onboard the patient) saves the doctor or front office some time.

> Breathless pronouncements from a supposed technical company that physicians will use their app because it "makes them feel modern" are a trifle annoying

Doctors want to feel modern. It helps bring in patients. How do you feel when you go to a doctor still using paper, and wait 5 minutes for them to shuffle through file folders to find your chart?

edit: formatting

jroll··on DrChrono Lets Doctors Accept Payments Via Square, View Real-Time Insurance Info
I've been working on our billing features and have worked with our X12 parser quite a bit. I died a little inside when I realized that I could scan X12 files almost as quickly as reading English. :P
jroll··on DrChrono Lets Doctors Accept Payments Via Square, View Real-Time Insurance Info
Correct. Square is used to pay copays or balances that may remain after insurance payments have been processed (deductibles, denials, etc.).

The main interface allows for the doctor to press one button to easily pay a known copay, or press another button to pay an arbitrary amount. In the screenshot here [1], the patient could pay his $490 balance by pressing the "Payment" button, or the $20 copay by pressing the "Copay" button.

[1] http://d.pr/i/Ulh5

edit: added a bit more detail

jroll··on Why Quit? Because the other company has bigger monitors.
General motors still runs their entire email system on Lotus Notes. Some people are even still running version 6, which I think is 2 or 3 versions behind...
jroll··on Want good programmers? Then pay them.
This is how we hire, and I think it's great. Both sides get to see if it's a good fit, we see how you work and if you have a product sense. You get to see if you like our product and company culture. Win-win.
jroll··on Ask HN: Who Is Hiring? (May 2012)
Mountain View - drchrono.com (YC W11) [full time and interns, H1B considered]

We're looking for more engineers and salespeople to help us revolutionize healthcare through mobile and web interfaces. Our stack includes Python/Django, iOS, and Android, but you don't need to be an expert, just ready and willing to learn fast! Our product supports thousands of doctors who depend on our systems daily to provide quality care to their patients, iPad in hand. The usual startup benefits included: competitive salary, healthcare, whatever hardware you need to be most productive.

Learn more at https://drchrono.com/jobs/

Apply via email: jobs@drchrono.com and/or take our hacker test at http://bit.ly/qbKAut

jroll··on Life's too short to write shitty software
I see that now, thanks :) I don't mind being downvoted, I'd just like to hear out any rebuttals to my comment.
jroll··on Life's too short to write shitty software
Out of curiosity, why the downvotes? When I worked at a corporation, I tried to do what Ed recommended here, and these are the problems that I encountered.
jroll··on Life's too short to write shitty software
And if you don't have the people to complete or maintain these projects? Or how about when you build out a prototype and then corporate IT policies end up having you generate hundreds of pages of documentation and a massive Java application, when your self-hosted 2k LOC Python project met all business requirements and specs?

I'd rather be in a position that encouraged rapid, pragmatic development.

jroll··on Ask HN: Who is Hiring? (April 2012)
Mountain View - drchrono.com (YC W11) [full time and interns]

We're looking for more engineers and salespeople to help us revolutionize healthcare through mobile and web interfaces. Our stack includes Python/Django, iOS, and Android, but you don't need to be an expert, just ready and willing to learn fast! Our product supports thousands of doctors who depend on our systems daily to provide quality care to their patients, iPad in hand. The usual startup benefits included: competitive salary, healthcare, whatever hardware you need to be most productive. email: jobs@[our-domain-name]

Take our hacker test at http://bit.ly/qbKAut

jroll··on OSX For Hackers
Been a Mac user for years and did not know this. Thanks!
jroll··on Down To Fax is Chatroulette for fax machines
There's http://hellofax.com, wonderful service.
jroll··on Please do not take down the Sality botnet
Sounds like the author figured out a SQL injection vulnerability in the website the bot downloads logos from, and a way to give the removal tool as the image in a way that infects Sality itself. This would distribute the removal tool very quickly. The hacking of the website seems to be the legal issue here.
jroll··on "Egor, stop hacking Github"
Hey Steve! Good to see another Kettering grad on here :)
jroll··on Hacked: commit to rails master on GitHub
The point of his hack was to _make_ him a contributor to rails.
jroll··on Show HN: Subway, a persistent web client for IRC
I'm aware there are other solutions. Compared to all the work I did to properly tunnel SSH over HTTPS (it was a pretty good firewall, apparently), deploying a node app is trivial.
jroll··on Show HN: Subway, a persistent web client for IRC
I would have loved to have this when I worked at a company that only allowed HTTP(S) through the firewall.
jroll··on Ask HN: Who is Hiring? (March 2012)
Mountain View - drchrono.com (YC W11) [full time and interns] We're looking for more engineers and salespeople to help us revolutionize healthcare through mobile and web interfaces. Our stack includes Python/Django, iOS, and Android, but you don't need to be an expert, just ready and willing to learn fast! Our product supports thousands of doctors who depend on our systems daily to provide quality care to their patients, iPad in hand. The usual startup benefits included: competitive salary, healthcare, whatever hardware you need to be most productive. email: jobs@[our-domain-name]

Take our hacker test at http://bit.ly/qbKAut

jroll··on What not to ask technical people in interviews
How do you figure that knowing the execution path for a basic language feature is an "arcane fact behind the scene?" This is equivalent to not knowing how an if or for statement works. You can't write ANY code without this knowledge.
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