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rripken

121 karma · joined February 11, 2015

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rripken··on Boring Co. Drops LA Westside Tunnel Plan
Unless you want to build a different tunnel or a basement, parking garage, ground source heat sink...
rripken··on I Can Be the Bank: Individual Investors Buy Busted Mortgages
Just b/c the eviction process is started doesn't mean the tenant can't resolve the problem before they are forced out. Assuming the tenant pays then waiting a week wouldn't matter. But if the tenant has decided that they won't pay then waiting the week delays the entire eviction process by an extra week - leading to the landlord getting 1 week less of income for every eviction. I have family that had to evict a tenant in California and it was an extremely long and drawn out process.
rripken··on Silent and Simple Ion Engine Powers a Plane with No Moving Parts
You may like Heinlein's "The Moon is a Harsh Mistress".
rripken··on The rise of the robot farmer
I do enterprise software, I have a small farm AND I just completed a masters in robotics. Probably wasn't intentional on your part but I feel like you just left a Baby Ruth in my pool.

Farming isn't horrible. Programming Enterprise Software isn't that hard. Safely doing robots in the real-world is.

rripken··on The rise of the robot farmer
We have mechanical harvesters in California but I haven't seen any that are gentle or use rubber flippers. Mechanical harvesters typically shake the trees/trunks a small amount but quite quickly. For grapes the shaking might move the top of the vine a foot or so at several hertz. The shaking is strong enough that most grapes are plucked off the stem merely because of the weight of the berry and the whip-like motion of the shaking. The newer style bow rod machines use multiple UHMW rods bent into a question mark like shape. A large number of materials were tried but UHMW is the strongest material that could be found for the application. If adamantium or vibranium could be sourced I'm sure it would be used.
rripken··on Ask HN: What's your favorite elegant/beautiful algorithm?
Lesson two of this course does a great job explaining K-means and its connection to Expectation Maximization. https://www.udacity.com/course/machine-learning-unsupervised...
rripken··on Moon Is Stepping Stone, Not Alternative to Mars, NASA Chief Says
If that's the case isn't the next step a base on Phobos or Deimos?
rripken··on Discovery of nitrogen-fixing corn variety could reduce need for added fertilizer
Can you link to more info about grapes fixing nitrogen? I've never heard of that.
rripken··on 3M Knew About the Dangers of PFOA and PFOS Decades Ago, Internal Documents Show
"Microwave Susceptor". Its a super thin layer of aluminum or graphite that absorbs microwaves and gets really hot. Its in the bottom layer of the bag and the reason for "this side up".
rripken··on A ‘delayed infection’ theory of childhood leukaemia
How can you tell that they lack nutrients? I have a basset hound and despite his supposedly excellent sense of smell he still enjoys "chocolate" snacks on a regular basis. He's an adult dog and getting Kirkland food. His weight is consistent and the vet is happy about what he weighs. I would love to be proven wrong (please!) but I doubt he's "snacking" because he lacks nutrients. I think he might be a little slow mentally and maybe he's _that_ hungry and doesn't have access to anything else to eat.
rripken··on Ask HN: What are the best MOOCs you've taken?
I've taken 10 GaTech OMSCS courses via Udacity. Two of my favorites (so far): Intro to Computer Vision: https://www.udacity.com/course/introduction-to-computer-visi... Reinforcement Learning: https://www.udacity.com/course/reinforcement-learning--ud600

I found the Isbell+Littman combo to work so well that I also took the ML course. I know some people complain about their humor but it was perfect for me. I could listen to those two explain just about anything. I still LOL when I think about Littman saying to Isbell something like "are you trying to teach us something by making this lecture infinitely long?" Who knew RL could be funny?

rripken··on An Update on Last Week’s Accident
Maybe SDC already do this, but it seems like the Agent should keep track of things that look like potential lanes and then if the potential lanes turn out to be not-lanes (have barrier in them) the Agent should flag the area that looked like the start of a lane so future SDC know to avoid it.
rripken··on Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona
So if you are going 10% faster (38 vs 35) you have 121% the kinetic energy.
rripken··on Lead is even deadlier than was feared
Have '48 Chevy - can confirm that lead-substitute exists and classic cars will run with it. I never use the car without it so its possible the stuff doesn't actually do anything.
rripken··on Bus Lane Blocked, He Trained His Computer to Catch Scofflaws
Seems like bus drivers need to be able to issue parking tickets for blocking bus lanes. Maybe add a camera to the bus that is only used when a car is actually found blocking the bus lane and have the images lead to tickets.
rripken··on Ask HN: Are there any studies about book reading retention rates vs. audiobooks?
I used to listen to lots of audiobooks b/c I had a long commute and I definitely agree that places get tied to specific passages. I believe it works both ways - re-reading books can sometimes make me remember the places and revisiting the places can remind me of the book that was playing. I'm now in Grad School and frequently listen to lectures during the drive. It makes test-taking interesting b/c some test questions cause me to think about geographic locations and then thinking about nearby geographic locations can sometimes remind me of the parts of the lecture that preceded or followed the material. Its the commuter's version of "Method of Loci".
rripken··on You need 16 times the sample size to estimate an interaction than a main effect
That 16x number is specific to a set of assumptions in the article. Is this just the Curse of Dimensionality in action? https://en.wikipedia.org/wiki/Curse_of_dimensionality
rripken··on Surprising Creativity: Anecdotes from Evolutionary Computation
Off topic - I find it humorous that arXiv list 49 authors and then ends the listed author list with: "et al. (1 additional author not shown)"

I know a line has got to be drawn somewhere but in this case, listing the last author (Jason Yosinksi) would have taken less space than the explanation that not all the authors are shown.

rripken··on California's other drought: a major earthquake is overdue
Isn't that enough time to start to slow BART trains?
rripken··on Compressing and enhancing hand-written notes (2016)
You are referring to the 10.1 tablet? I know its not the same but I had a Note4 and was pleased with its note taking ability. I imagine that with the extra screen real-estate the tablet was even better. It looks like they are $453 on Newegg! I agree that does seem crazy for an old device. If you can put up with a used device there are two on swappa for around $200 https://swappa.com/buy/samsung-galaxy-note-101-2014-wifi If it truly is the hands-down best note taking tablet you might as well buy them both and standardize to the platform.
rripken··on Exim Off-By-one RCE: Exploiting CVE-2018-6789 with Fully Mitigations Bypassing
Previous devcore article (https://devco.re/blog/2017/12/11/Exim-RCE-advisory-CVE-2017-... ) about another Exim bug mentions fuzzing. I suspect that is how this issue was found but I'd love more details if anyone knows anything.
rripken··on Exim Off-By-one RCE: Exploiting CVE-2018-6789 with Fully Mitigations Bypassing
"Vulnerabilities found by Meh, DEVCORE research team." Any more details regarding how the flaw was found? I don't see an Exim entry in the AFL trophy case http://lcamtuf.coredump.cx/afl/ Also nothing about Exim on oss-fuzz.
rripken··on Machine Learning Crash Course
I think Weka gets used in the java world. https://www.cs.waikato.ac.nz/ml/weka/
rripken··on Machine Learning Crash Course
Georgia Tech has an graduate course on Machine Learning CS-7641. There are four major projects in that course where the students must analyze (and re-analyze) a chosen dataset. Here is an example of the code one student used: https://github.com/JonathanTay/CS-7641-assignment-1 Unfortunately all the plotting code was intentionally removed. Sometimes the project reports make it online (http://www.dudonwai.com/docs/gt-omscs-cs7641-a3.pdf?pdf=gt-o...) . Having spent several months of my life on the assignments I'd say that only way to learn it is to try a whole bunch of different things and try and figure out why some work and why some don't. Sometimes you learn from the failures, sometimes from the unexpected successes.
rripken··on Intel Responds to Security Research Findings
If the processor is 30% slower, the same amount of work is going to take 43% longer - right? If I'm renting machines by the hour my costs just went up 43%.
rripken··on Game Theory: Open Access textbook
The last two lectures in the The Georgia Tech Machine Learning course on Udacity cover some basics of Game Theory. Just skip ahead, the game theory part is mostly self-contained. https://www.udacity.com/course/machine-learning--ud262 The Reinforcement Learning course includes some of the same (exactly the same) game theory content and then adds an additional lecture on further topics in game theory https://www.udacity.com/course/reinforcement-learning--ud600 Again, skip to the last couple lectures.
rripken··on Zsync: Differential file downloading over HTTP using the rsync algorithm (2010)
Interesting. How would that work for clients? If the destination file already exists on the client look for a .zsync on the hosting server, if its not there look for one at https://thirdpartyzsyncs.com?url=someurl ? What happens if the .zsync is out of sync with the resource?
rripken··on A Coca-Cola plant in Mexico uses 1.08M liters of water per day as wells dry up
I sort of thought Almonds was _the_ reason we have migrating honeybees in the United States (or North America). In any case Zaiger Genetics have bred self-fertile Almonds that don't require bees. The trees are starting to be planted: http://www.growingproduce.com/nuts/self-fertile-almond-domin... Almond trees take a significant amount of time to mature. While orchards can be retrofitted the irrigation infrastructure is typically installed before the trees are planted. This means that the water use of an orchard currently producing almonds was probably designed in the 90s. All the new orchards I see being planted are using drip. In 2030 I suspect the water use per kg of almonds will be much lower than it is today.
rripken··on Ask HN: Is Georgia Tech's Online Master in CS Worth It?
I look forward to it.
rripken··on Ask HN: Is Georgia Tech's Online Master in CS Worth It?
I didn't need GRE scores but letters of recommendation are required.
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